Monkeypox, Monkeypox, Oh My!

Monkeypox is a viral disease that occurs mainly in central and western Africa. The World Helath Organization (WHO) confirmed on June 1, 2022, more than 550 monkeypox cases across 30 countries as the virus continues to spread across the globe.

Monkeypox was first discovered in 1958 when two outbreaks of a pox-like disease occurred in colonies of monkeys kept for research, hence the name ‘monkeypox.’ The first human case of monkeypox was recorded in 1970 in the Democratic Republic of Congo during a period of intensified effort to eliminate smallpox. Since then monkeypox has been reported in humans in other central and western African countries.

Images of a child with monkeypox, a lab worker, and vaccine.

Monkeypox is a rare disease that is caused by infection with monkeypox virus.

Monkeypox is a rare disease that is caused by infection with monkeypox virus. Monkeypox virus belongs to the Orthopoxvirus genus in the family Poxviridae. The Orthopoxvirus genus also includes variola virus (which causes smallpox), vaccinia virus (used in the smallpox vaccine), and cowpox virus.

Monkeypox was first discovered in 1958 when two outbreaks of a pox-like disease occurred in colonies of monkeys kept for research, hence the name ‘monkeypox.’ The first human case of monkeypox was recorded in 1970 in the Democratic Republic of the Congo (DRC) during a period of intensified effort to eliminate smallpox. Since then, monkeypox has been reported in people in several other central and western African countries: Cameroon, Central African Republic, Cote d’Ivoire, Democratic Republic of the Congo, Gabon, Liberia, Nigeria, Republic of the Congo, and Sierra Leone. The majority of infections are in Democratic Republic of the Congo.

Monkeypox cases in people have occurred outside of Africa linked to international travel or imported animals, including cases in the United States, as well as Israel, Singapore, and the United Kingdom.

The natural reservoir of monkeypox remains unknown. However, African rodents and non-human primates (like monkeys) may harbor the virus and infect people.

Signs and Symptoms

In humans, the symptoms of monkeypox are similar to but milder than the symptoms of smallpox. Monkeypox begins with fever, headache, muscle aches, and exhaustion. The main difference between symptoms of smallpox and monkeypox is that monkeypox causes lymph nodes to swell (lymphadenopathy) while smallpox does not. The incubation period (time from infection to symptoms) for monkeypox is usually 7−14 days but can range from 5−21 days.

The illness begins with:

  • Fever
  • Headache
  • Muscle aches
  • Backache
  • Swollen lymph nodes
  • Chills
  • Exhaustion

Within 1 to 3 days (sometimes longer) after the appearance of fever, the patient develops a rash, often beginning on the face then spreading to other parts of the body.

Lesions progress through the following stages before falling off:

  • Macules
  • Papules
  • Vesicles
  • Pustules
  • Scabs

The illness typically lasts for 2−4 weeks. In Africa, monkeypox has been shown to cause death in as many as 1 in 10 persons who contract the disease.

Transmission

Monkeypox virus can spread when a person comes into contact with the virus from an infected animal, infected person, or materials contaminated with the virus. The virus can also cross the placenta from the mother to her fetus. Monkeypox virus may spread from animals to people through the bite or scratch of an infected animal, by handling wild game, or through the use of products made from infected animals. The virus may also spread through direct contact with body fluids or sores on an infected person or with materials that have touched body fluids or sores, such as clothing or linens.

Monkeypox spreads between people primarily through direct contact with infectious sores, scabs, or body fluids. It also can be spread by respiratory secretions during prolonged, face-to-face contact. Monkeypox can spread during intimate contact between people, including during sex, as well as activities like kissing, cuddling, or touching parts of the body with monkeypox sores. At this time, it is not known if monkeypox can spread through semen or vaginal fluids.

It is not yet known what animal maintains the virus in nature, although African rodents are suspected to play a part in monkeypox transmission to people.

Prevention

There are number of measures that can be taken to prevent infection with monkeypox virus:

  • Avoid contact with animals that could harbor the virus (including animals that are sick or that have been found dead in areas where monkeypox occurs).
  • Avoid contact with any materials, such as bedding, that has been in contact with a sick animal.
  • Isolate infected patients from others who could be at risk for infection.
  • Practice good hand hygiene after contact with infected animals or humans. For example, washing your hands with soap and water or using an alcohol-based hand sanitizer.
  • Use personal protective equipment (PPE) when caring for patients.

Interim Clinical Guidance for the Treatment of Monkeypox

Many individuals infected with monkeypox virus have a mild, self-limiting disease course in the absence of specific therapy. However, the prognosis for monkeypox depends on multiple factors such as previous vaccination status, initial health status, concurrent illnesses, and comorbidities among others. Persons who should be considered for treatment following consultation with CDC might include:

  • Persons with severe disease (e.g., hemorrhagic disease, confluent lesions, sepsis, encephalitis, or other conditions requiring hospitalization)
  • Persons who may be at high risk of severe disease:
    • Persons with immunocompromise (e.g., human immunodeficiency virus/acquired immune deficiency syndrome infection, leukemia, lymphoma, generalized malignancy, solid organ transplantation, therapy with alkylating agents, antimetabolites, radiation, tumor necrosis factor inhibitors, high-dose corticosteroids, being a recipient with hematopoietic stem cell transplant <24 months post-transplant or ≥24 months but with graft-versus-host disease or disease relapse, or having autoimmune disease with immunodeficiency as a clinical component)1
    • Pediatric populations, particularly patients younger than 8 years of age2
    • Pregnant or breastfeeding women3
    • Persons with one or more complications (e.g., secondary bacterial skin infection; gastroenteritis with severe nausea/vomiting, diarrhea, or dehydration; bronchopneumonia; concurrent disease or other comorbidities)4
  • Persons with monkeypox virus aberrant infections that include its accidental implantation in eyes, mouth, or other anatomical areas where monkeypox virus infection might constitute a special hazard (e.g., the genitals or anus)

Medical Countermeasures Available for the Treatment of Monkeypox

Currently there is no specific treatment approved for monkeypox virus infections. However, antivirals developed for use in patients with smallpox may prove beneficial. The following medical countermeasures are currently available from the Strategic National Stockpile (SNS) as options for the treatment of monkeypox:

  • Tecovirimat (also known as TPOXX) is an antiviral medication that is approved by the United States Food and Drug Administration (FDA) pdf icon[PDF – 24 pages]external icon for the treatment of human smallpox disease in adults and pediatric patients weighing at least 3 kg. CDC holds an Expanded Access Investigational New Drug Protocol (EA-IND) that allows for the use of Tecovirimat for the treatment of non-variola orthopoxviruses (including monkeypox) in an outbreak. This protocol includes allowance for opening an oral capsule of tecovirimat and mixing its content with semi-solid food for pediatric patients weighing less than 13 kg. Tecovirimat is available as oral (200 mg capsule) and injection for intravenous formulations.
  • Cidofovir (also known as Vistide) is an antiviral medication that is approved by the FDA pdf icon[PDF – 6 pages]external icon for the treatment of cytomegalovirus (CMV) retinitis in patients with Acquired Immunodeficiency Syndrome (AIDS). CDC holds an EA-IND that allows for the use of Cidofovir for the treatment of orthopoxviruses (including monkeypox) in an outbreak.
  • Vaccinia Immune Globulin Intravenous (VIGIV) is licensed by FDAexternal icon for the treatment of complications due to vaccinia vaccination including eczema vaccinatum, progressive vaccinia, severe generalized vaccinia, vaccinia infections in individuals who have skin conditions, and aberrant infections induced by vaccinia virus (except in cases of isolated keratitis). CDC holds and EA-IND that allows the use of VIGIV for the treatment of orthopoxviruses (including monkeypox) in an outbreak.

Brincidofovir (also known as Tembexa) is an antiviral medication that was approved by the FDA pdf icon[PDF – 18 pages]external icon on June 4, 2021 for the treatment of human smallpox disease in adult and pediatric patients, including neonates. CDC is currently developing an EA-IND to help facilitate use of Brincidofovir as a treatment for monkeypox. However, Brincidofovir is not currently available from the SNS.

It’s been three weeks since public-health authorities confirmed a case of monkeypox in the United Kingdom. Since then, more than 400 confirmed or suspected cases have emerged in at least 20 non-African nations, including Canada, Portugal, Spain and the United Kingdom — the largest outbreak ever seen outside Africa. The situation has scientists on alert, because the monkeypox virus has emerged in separate populations across multiple countries, and there is no obvious link between many of the clusters, raising the possibility of undetected local transmission of the virus.

“We need to act quickly and decisively, but there is still a lot to be learned,” says Anne Rimoin, an epidemiologist at the University of California, Los Angeles, who has studied monkeypox in the Democratic Republic of the Congo for more than a decade.

Nature outlines some of the key questions about the recent outbreaks that researchers are racing to answer.

How did the current outbreaks start?

Since the latest outbreaks began, researchers have sequenced viral genomes collected from people with monkeypox in countries including Belgium, France, Germany, Portugal and the United States. The most important insight they have gained so far is that each of the sequences closely resembles that of a monkeypox strain found in West Africa. The strain has a death rate of less than 1% in poor, rural populations, making it much less lethal than another that has been detected in Central Africa. That one has a fatality rate of up to 10%.

Clues have also emerged about how the outbreak might have begun. Although researchers need more data to confirm their suspicions, the sequences they have evaluated so far are nearly identical, suggesting that a thorough epidemiological investigation might find that the recent outbreaks outside Africa all link back to a single case.

The current sequences are most similar to those from a smattering of monkeypox cases that arose outside Africa in 2018 and 2019 that were linked to travel in West Africa. The simplest explanation is that the person who had the first non-African case this year — who has still not been identified — became infected through contact with an animal or human carrying the virus while visiting a similar part of Africa, says Bernie Moss, a virologist at the National Institute of Allergy and Infectious Diseases in Bethesda, Maryland.

But other explanations cannot be ruled out, says Gustavo Palacios, a virologist at the Icahn School of Medicine at Mount Sinai in New York City. It’s possible that the virus was already circulating, undetected, outside Africa in humans or animals, having been introduced during earlier outbreaks. This hypothesis, however, is less likely because monkeypox usually causes visible lesions on people’s bodies — which would probably be brought to the attention of a physician.

Could a genetic change in the virus explain the latest outbreaks?

Understanding whether there is a genetic basis for the virus’s unprecedented spread outside Africa will be incredibly difficult, says Elliot Lefkowitz, a computational virologist at the University of Alabama at Birmingham who has studied poxvirus evolution. Researchers are still struggling to determine precisely which genes are responsible for the higher virulence and transmissibility of the Central African strain compared with the West African one more than 17 years after they identified a difference between the two.

One reason for this is that poxvirus genomes contain many mysteries, Lefkowitz says. The monkeypox genome is enormous relative to that of many other viruses — it is more than six times as large as the genome for the SARS-CoV-2 coronavirus. That means monkeypox genomes are at least “six times harder to analyse”, says Rachel Roper, a virologist at East Carolina University in Greenville, North Carolina.

Another reason, Palacios says, is that few resources have been dedicated to genomic-surveillance efforts in Africa, where monkeypox has been a public-health concern for many years. So virologists are in the dark, because they have few sequences to which they can compare the new monkeypox sequences, he says. Funding agencies have not heeded scientists, who have been warning for more than a decade1 that further monkeypox outbreaks could occur, he adds.

Ifedayo Adetifa, the head of the Nigeria Centre for Disease Control in Abuja, says that African virologists he’s spoken to have expressed irritation that they’ve struggled to garner funding and publish studies about monkeypox for years — but that now it’s spread outside the continent, public-health authorities worldwide suddenly seem interested.

To understand how the virus evolves, it would also be useful to sequence the virus in animals, Palacios says. The virus is known to infect animals — mainly rodents such as squirrels and rats — but scientists have yet to discover its natural animal reservoir in the affected areas of Africa.

Can the outbreaks be contained?

Since the current outbreaks began, some nations have been procuring smallpox vaccines, which are thought to be highly effective against monkeypox, because the viruses are related. Unlike some vaccines against COVID-19, which take up to two weeks after a second dose to offer full protection, smallpox vaccines are thought to protect against monkeypox infection if administered within four days of exposure because of the virus’s long incubation period, according to the US Centers for Disease Control and Prevention (CDC) in Atlanta, Georgia.

If deployed, the vaccines would probably be used in a ‘ring vaccination’ strategy, which would inoculate close contacts of infected people. Andrea McCollum, an epidemiologist who heads the poxvirus team at the CDC, says that the agency is not yet deploying such a strategy. But CNN reports that the United States plans to offer smallpox vaccines to some health-care workers treating infected people. It might also be worth considering vaccinating groups at a higher risk of infection, in addition to close contacts of infected people, Rimoin says.

Even if public-health officials can halt the transmission of monkeypox in humans during the current outbreaks, virologists are concerned that the virus could spill back into animals. Having new reservoirs of virus in animals would increase the probability of it being transmitted to people again and again, in countries including those that don’t have any known animal reservoirs of the virus. On 23 May, the European Centre for Disease Prevention and Control highlighted this possibility, but deemed the probability “very low”. Nevertheless, European health officials strongly recommended that pet rodents such as hamsters and guinea pigs belonging to people with confirmed cases of monkeypox be either isolated and monitored in government facilities or, as a last resort, euthanized, to avoid the possibility of spillover.

Although the risk is low, Moss says the main concern is that scientists wouldn’t know if such a spillover event occurred until it was too late, because infected animals typically don’t show the same visible symptoms seen in humans.

Is the virus spreading differently compared with previous outbreaks?

Monkeypox virus is known to spread through close contact with the lesions, bodily fluids and respiratory droplets of infected people or animals. But health officials have been examining sexual activity at two raves in Spain and Belgium as drivers of monkeypox transmission, according to the Associated Press, raising speculation that the virus has evolved to become more adept at sexual transmission.

The linking of cases to sexual activity doesn’t mean that the virus is more contagious or is transmitted sexually, however — just that the virus spreads readily through close contact, Rimoin says. Unlike SARS-CoV-2, which isn’t thought to linger on surfaces much, poxviruses can survive for a long time outside the body, making surfaces such as bedsheets and doorknobs potential vectors of transmission, Roper says.

Although health officials have noted that many cases have been among men who have sex with men (MSM), Rimoin emphasizes that the most likely explanation for the virus’s spread among MSM groups is that the virus was coincidentally introduced into the community, and it has continued spreading there.

All of the new attention on monkeypox has laid bare just how much scientists have yet to understand about the virus, McCollum says. “When this has all settled down, I think we’ll have to think long and hard about where the research priorities are,” she says.

Monkeypox cases are rising—here’s what we know so far

An outbreak of monkeypox, which is related to smallpox, has public health officials concerned. But the virus can be contained with vaccines that are already stockpiled and available in some countries.

When experts in the United Kingdom confirmed the first case of monkeypox on May 7 this year, epidemiologist Andrea McCollum and her colleagues at the United States Centers for Disease Control and Prevention kept a close watch.

Human monkeypox infections are rare, especially outside of Central and Western Africa where the virus is endemic in animals and circulates primarily in heavily forested areas. Since 2018, only eight cases had been confirmed in non-endemic countries including Israel, Singapore, the U.K., and the U.S.—and all were associated with travel, just like the May 7 patient, who had taken a trip to Nigeria.

But as cases with no known travel links to Africa popped up in several countries, alarm bells went off, McCollum says. “We’ve never really seen this type of observation from monkeypox before,” she says, “so this is particularly concerning.”

Between May 13 and 24, at least 16 countries in Europe and North America, as well as Australia and Israel, reported more than 250 confirmed and suspected monkeypox cases. The West African strain of the virus seems to be causing these infections. It triggers flu-like symptoms followed by a rash on the face which can spread to other parts of the body. This rash transforms from red spots to pus-filled blisters that eventually scab and fall off. Most often, these symptoms go away on their own within a few weeks, but they are fatal in about three percent of the cases. Its counterpart, the Congo Basin monkeypox strain, causes a more severe disease and kills nearly 10 percent of those infected. The smallpox virus, which was eradicated in 1979 and is a close relative of monkeypox, was much deadlier, killing 30 percent of those infected.

“It [monkeypox] is very different from COVID,” saidMaria Van Kerkhove, an infectious disease epidemiologist at the World Health Organization, at an online public Q&A on May 23. “Transmission is really happening from close physical contact, skin-to-skin contact.” Monkeypox, unlike COVID-19 which circulates via tiny air-borne droplets, doesn’t spread as easily.

“This is a containable situation,” Van Kerkhove said. There are potential antivirals for those infected and vaccines for people most at risk: those who come in close contact with infected individuals. This [vaccination] is not something that everybody needs,” she said.

Fortunately, so far, no one has died in this ongoing multi-country monkeypox outbreak, but where it began and what’s causing its spread remains unknown.

At the moment, there are many open questions, McCollum says.

Here’s what we know so far.

Cases to date

Since the identification of the May 7 patient, monkeypox case numbers in non-endemic countries have increased.

Public health officials are now contact tracing and searching for connections between the cases to find clues. This might also help them locate undiagnosed cases that could potentially be asymptomatic or have mild symptoms.

A large proportion of the currently confirmed cases have been reported from Europe, particularly the U.K., Spain, and Portugal. Most of these infections were among men, many who self-identified as men who had sex with men. In a May 23 interview with The Associated Press, a key advisor to the WHO said that the leading theory to explain the ongoing outbreak was sexual activity among men at two recent raves in Spain and Belgium.

How is the disease transmitted? 

Although monkeypox can spread through sexual contact, it’s not a sexually transmitted infection, said Andy Seale, an advisor to WHO’s HIV, hepatitis, and sexually transmitted infections program, at an online public Q&A on May 23. That typically requires the infectious virus to be carried via semen or vaginal fluids, and currently there is no evidence to suggest that.

The disease is not confined to men who have sex with men. “Anybody can contract monkeypox through close contact,” Seale said.

The disease spreads via an infected person’s bodily fluids—spit or pus—that can harbor the virus. Bedsheets or clothes contaminated with such virus-laden fluid can also be a potential source of infection.

Given the widespread nature of the current outbreak, epidemiologists and virologists are trying to understand if there’s enhanced person-to-person transmission of this virus. Some experts are studying the genetic sequences of the virus obtained from infected patients to see if there are any mutations that could make the currently circulating virus potentially more transmissible than any previous versions. They’re also checking whether the monekypox virus is present in semen or vaginal fluids, and if it is infectious, to confirm this isn’t a sexually transmitted disease.

Are there vaccines and treatments for monkeypox?

Not all monkeypox patients are hospitalized; many get better on their own without treatment while isolating at home for three weeks. Some countries, including the U.K., advise those who had close contact with the infected individual to quarantine for 21 days. In the U.S., President Biden said that such quarantining is not needed as vaccines are available for those exposed to the virus.

In 2019, the U.S. Food and Drug Administration approved Bavarian Nordic’s monkeypox vaccine called Jynneos, which can prevent the disease or make it less severe. Another vaccine called ACAM2000 that’s approved for smallpox could also be used. The U.S. and the U.K., for instance, are offering the Jynneos vaccine to healthcare workers who treat or may have been exposed to infected patients. The CDC suggests getting the two-dose vaccine within four days of exposure.

However, no medications have been approved to treat monkeypox. An oral antiviral drug called Tecovirimat was approved by the FDA in 2018 for smallpox treatment, but there is no data to show it is effective in humans for either of these infections. For severe monkeypox illness, two other therapeutics, an antiviral cidofovir and a monoclonal antibody called vaccinia immune globulin may be used.

How does monkeypox differ from SARS-CoV-2?

Unlike SARS-CoV-2, the RNA virus that causes COVID-19, monkeypox virus is a DNA virus. Its genome is encoded with about 200,000 genetic units whereas the SARS-CoV-2 genome is much smaller: roughly 30,000 units. Such DNA viruses tend not to mutate, said Rosamund Lewis, head of WHO’s Smallpox Secretariat, at an online public Q&A on May 23, and tend to be fairly stable and less likely to generate variants.

The two viruses also transmit somewhat differently. SARS-CoV-2 spreads quickly through the air in tiny droplets when infected people speak, sneeze, or cough. Monkeypox doesn’t spread as easily by air and often requires close physical contact with an infected person or their contaminated clothes or bedding.

Short history of monkeypox

The virus was first discovered in 1958 in Denmark when researchers noticed pox-like skin eruptions on cynomolgus monkeys that came from Singapore and were housed in an animal research facility—hence the name monkeypox. In the next decade, more outbreaks were reported in the U.S. in captive monkeys imported from Asia, where monkeypox hadn’t been identified. These primates were considered accidental hosts of the virus.

The first human monkeypox infection was documented in 1970 in the Congo’s Équateur Province in a nine-month-old baby who was initially thought to have smallpox—a disease that was close to eradication and resembled monkeypox. By 1985, the World Health Organization had recorded 310 monkeypox cases in rural West and Central Africa, with the majority in Congo.

This prompted a search for the primary source of the monkeypox virus. A 1985 survey of 383 wild animals including monkeys, rodents, and bats in northern Congo revealed monkeypox-specific antibodies in the blood samples of two Thomas’s rope squirrel—a diurnal rodent, which is likely hunted and consumed for meat. One of the squirrels had skin eruptions and researchers successfully isolated a monkeypox virus identical to the ones seen in humans from the animal’s tissues.

In March 2012, another team of researchers isolated the virus from a monkey species called sooty mangabey in Côte d’Ivoire’s Taï National Park andin 2020 from western chimpanzeesRecently, another study that’s yet to be peer-reviewed has found evidence of the virus in shrews and some rodentsliving in the Congo Basin.

While rodents are suspected to be the primary reservoirs of monkeypox, there’s no direct evidence which shows that these animals, hunted for meat or kept as pets, spread the virus to humans, says Joachim Mariën, a disease ecologist at Belgium’s University of Antwerp. 

Still, the infamous 2003 monkeypox outbreak in the U.S.—thefirst outside Africaprovides a glimpse of how animal-to-human transmission of this virus occurs. At least 37 peoplefrom six states:Illinois, Indiana, Kansas, Missouri, Ohio, and Wisconsin became ill after handling or petting infected prairie dogs. Turns out, these rodents very likely caught the monkeypox virus while being housed alongside dormice and Gambian giant pouched rats that an Illinois animal distributor imported from Ghana.

Why are monkeypox cases rising?

In parts of Central and West Africa, where the virus is endemic, human monkeypox cases have been rising since the 1970s. A 2022 study estimated a minimum 10-fold increase in global confirmed, probable, and possible case numbers in the last five decades. That increase is most dramatic in Congo, which recorded more than 28,000 cases between 2000 and 2019, and in Nigeria, where the disease reemerged in 2017 after 40 years.

One big reason for escalating monkeypox cases is the elimination of smallpox. In 1980, the World Health Organization declared smallpox eradicated and vaccination against the virus ended. But researchers have shown that this discontinued smallpox vaccine, which can have side effects, provided 85 percent protection against monkeypoxA 2010 study from Central Congo found that vaccinated people had a nearly fivefold lower risk of getting monkeypox than unvaccinated ones. 

Escalating deforestation can also expose more people to the virus. Clearing of forests to make way for plantations and agriculture is likely to bring humans closer to infected wild animals, increasing opportunities for the virus to jump species, as is suggested for Ebola.

Also, a2014 studydocumented one version of the Congo Basin monkeypox virus strain with a deleted gene that may be associated with an adaptation for human-to-human transmission.

“We knew that monkeypox was a disease we needed to keep a close eye on because of its epidemic potential,” saysLaurens Liesenborghs,an infectious disease specialist studying the virus at the Institute of Tropical Medicine in Belgium. “However, what’s happening now is something quite peculiar.”

Is this monkeypox outbreak caused by a more transmissible virus?

Another lingering question is whether the virus evolved to spread more easily among humans. For pox viruses, which are DNA viruses, that typically means either losing or gaining genes that make it more transmissible, says Gustavo Palacios, a virologist at the Icahn School of Medicine at Mount Sinai in New York.

Based on the genome sequences of the virus taken from three recently infected monkeypox patients from Portugal, Belgium, and the U.S., there is no evidence for such gene deletion or addition, he says. In fact, the Portugal genome draft sequence presents a close match with that of the virus exported from Nigeria to Israel, Singapore, and the U.K. in 2018 and 2019. The draft gene sequence from Belgium is very similar to that obtained from the Portuguese patient, which makes sense, says Philippe Selhorst, a virologist at the Institute of Tropical Medicine in Belgium, given that the Belgian man had recently traveled to Portugal.

But to identify subtle changes in the monkeypox genetic makeup, researchers need to sequence viral DNA from more patients and compare regions across the genome that may be different to sequences from previous outbreaks. The question is whether those variations, if found, amount to how the virus infects humans.

Selhorst’s worry, however, is that even if the virus hasn’t changed yet, it might have more opportunities to mutate, the longer this ongoing outbreak continues.

Even though monkeypox is not as contagious as COVID-19, Selhorst says “it’s just never good when a virus that’s been in an animal reservoir is now circulating more and more in people.”

How contagious is monkeypox—and should you get a vaccine? Here’s the latest.

The disease is now global and is spreading rapidly, but there are simple ways to lower your risk of infection. Here’s what you need to know.

(Update 7/10/2022)

In a world exhausted by two-plus years of the coronavirus pandemic, another disease, monkeypox, continues to spread more rapidly than ever before. It’s a very different virus from the one that causes COVID-19, and is much harder to transmit, but it can land patients in the hospital and even kill. Monkeypox can also leave the infected disfigured: The pus-filled lesions that pock the skin—anywhere from a few to thousands—can leave permanent scars.

So far, 61 countries on six continents have recorded 7,492 cases, with a 82 percent increase in new infections since June 27. In the United States, monkeypox has breached 34 states, the District of Columbia, and Puerto Rico. Cases currently number 700 and while most illness has been relatively mild, there have been three confirmed deaths in Africa. The disease is largely circulating in a particular network, men who have sex with men.

But it’s likely that “a significant number of cases are not being picked up,” says World Health Organization Director-General Tedros Adhanom Ghebreyesus. Beyond limited testing, some patients present with relatively few lesions, further complicating the case count.

Transmission has entered uncharted territory, with monkeypox cases among people who haven’t traveled to Africa—where the virus is endemic—and infections popping up in new places. “There is simply no room for complacency—especially right here in the European Region with its fast-moving outbreak that with every hour, day, and week is extending its reach into previously unaffected areas,” Hans Henri P. Klugethe WHO Regional Director for Europe, said in a statement.

WHO’s Emergency Committee will reconsider whether the outbreak constitutes a global public health emergency the week of July 18. They noted that controlling the spread of monkeypox requires “intense response efforts.”

This current multi-country outbreak was “a surprise,” but “not surprising,” says Rosamund Lewis, who serves as the monkeypox technical lead at the WHO. Cases have been rising for decades in Africa. An ongoing outbreak in Nigeria began in 2017 (and may be the origin of this current spread) and another in the Democratic Republic of the Congo (DRC) counted some 6,000 suspected cases in in 2020.

While COVID-19 cases dwarf those from monkeypox, experts are concerned that humans may infect wild animals in the U.S. or other nations, inadvertently creating new endemic reservoirs for the disease, says Andrea McCollum, an epidemiologist with the Centers for Disease Control and Prevention’s (CDC) 2022 Monkeypox Outbreak Response effort. Animals could then retransmit the virus to people, making it much more difficult—or impossible—to eradicate.

There are now global efforts to prevent the spread of monkeypox cases and avert another pandemic. Towards that end, public health officials are offering vaccination to those at risk. The Biden administration is ramping up delivery of vaccines which have been in tight demand.

Here’s what you need to know about the virus, risk, prevention, and whether you need a monkeypox vaccination.

What is monkeypox?

Monkeypox is a much less severe, less contagious cousin of smallpox. Both are orthopoxviruses, a genus of 12 DNA viruses that also includes cowpox and camelpox.

There are two distinct genetic clades, or varieties, explains Bernard Moss, a virologist at the U.S. National Institute of Allergy and Infectious Diseases (NIAID). One, Congo Basin monkeypox, kills one in 10 of those infected. The current global outbreak is confirmed to be the second variety, the less deadly West African monkeypox, which has a mortality rate of less than one percent.

It’s a zoonotic disease, transmitted to humans by animals. First discovered in 1958 among monkeys in a Danish research lab, the virus’s name may or may not be a misnomer. Small mammals are thought to harbor the virus in African rainforests where it’s endemic, but it can infect many mammals and has only been isolated in wild animals twice: a rope squirrel in the DRC in 1985 and a mangabey in Cote d’Ivoire in 2012. The actual disease reservoir(s) remain unknown.

Since the first known human case in 1970—when an infant boy was diagnosed in DRC—most infections have occurred in West and Central Africa. Early on, most were “spillover events,” contracted from hunting and butchering infected wild animals, says Lewis.

Close contact can then spread the virus between people. The lesions are contagious “little viral factories,” says CDC’s McCollum. But until recently, the virus rarely spread beyond a few households within a community.

Though this disease was characterized at least 52 years ago, “we actually don’t know nearly as much as we would like to,” says Lewis.

Is it a sexually transmitted disease?

Though one of the initial cases infected a mother, father, and their infant in the United Kingdom, the current monkeypox outbreak has overwhelmingly affected men who have sex with men—99 percent among cases that have reported gender. For public health officials, it’s been challenging to educate the public without stigmatizing that community.

The outbreak was likely amplified by sexual behavior at raves in Spain and Belgium, David Heymann, a longtime WHO infectious disease expert, told the Associated Press. Those events seeded international spread, much like large gatherings disseminated COVID-19 during the early days of the pandemic.

But evidence suggests that monkeypox is not an STD, says Moss. When someone is symptomatic, it’s spread skin-to-skin—including through sexual behaviors—and can also be transmitted through contact with bedsheets, towels, or clothing.

Previous outbreaks in Africa have infected women, children, and men of all ages. “There are no guardrails. This virus is not necessarily going to stay within one gender or one population,” warns Anne Rimoin, an infectious disease epidemiologist and professor at the University of California Los Angeles School of Public Health. That is already happening. The WHO has started seeing cases in children, Lewis says.

She calls this an evolving situation that must be carefully monitored. “I think we need to have our eyes wide open and be ready to react.”

Public education is key. “We don’t want people to worry, but awareness is what you need to protect yourself,” Lewis adds. “What we need is for each person to know their own risk…and manage it.”

Are tests and vaccines readily available in the U.S.?

There are existing tests for monkeypox, which involve simply swabbing a lesion. Tests are then shipped to an in-state lab to confirm orthopox, then sent on to the CDC to confirm monkeypox. With a positive orthopox result, patients are being preemptively treated.

Despite existing U.S. Laboratory Response Network testing for infectious disease, advocates have complained of backlogs and delays in testing and results; demand is currently concentrated in urbans areas. To date, California, New York, Illinois, and Florida are the most affected, according to the CDC. To make tests more available, the Department of Health and Human Services (HHS) will be shipping orthopox virus tests to five commercial labs.

Vaccines have been hard to get, but that is changing. After the first U.S. case was logged on May 18, numbers surged and monkeypox vaccines were quickly depleted. On June 28, the Biden administration announced that it would distribute 56,000 additional doses, prioritizing areas with the greatest transmission. Another 240,000 doses will be distributed in the coming weeks, with a total of 1.6 million available by late fall.

There is no approved treatment specifically for monkeypox, but antivirals developed for smallpox may help, according to the CDC.

Should I get monkeypox vaccine? Who is being prioritized for vaccination?

“Vaccination of the general population is not warranted,” says NIAID’s Moss. At present, the virus is only spreading within a small demographic.

But amidst this mushrooming outbreak, contact tracing is no longer possible. Some countries, including the U.S., have had to pivot, with plans to expand vaccination from just those with known contacts to include anyone at high-risk.

“Vaccination is best if it’s given before someone gets infected,” says Moss. Post exposure, the target window is four days, but people can be vaccinated up to two weeks after.

What is the difference between the two monkeypox vaccines—and when were they developed? 

Edward Jenner, considered the founder of vaccinology in the West, successfully inoculated an eight-year-old boy against smallpox in 1796 using vaccinia virus—from cowpox. Two years later, researchers developed the first smallpox vaccine. Since orthopox viruses share 90 percent or more of their genetics, “a vaccine made against any one of them is protective against all of them,” Moss says.

Unlike the situation with the dawning COVID-19 pandemic in 2020, the good news is that we have vaccines that should work against monkeypox, Lewis says. Two are available in the U.S. The Food and Drug Administration approved ACAM2000 in 2007 to prevent smallpox. It resembles the early vaccines, using live, mild vaccinia virus, and has been used by the military, laboratory workers, and other groups for decades. Those who were vaccinated against smallpox before the U.S. ended its program in 1972 should have some lingering immunity.

The current smallpox vaccines have never been tested in phase III clinical trials against either smallpox or monkeypox. While health professionals believe that smallpox vaccines work against monkeypox, “this has not yet actually been demonstrated in rigorous studies,” says Lewis, “or even in ‘real life’ at this time.”

Certain groups should avoid this live vaccine. They include those who are pregnant, as it can endanger an unborn child. The immunocompromised or those with skin conditions should also steer clear: the virus can spread uncontrolled. This vaccine can also be dangerous for those with cardiac problems, as it can trigger heart inflammation.

The second vaccine, Jynneos, carries far fewer side effects and is the only vaccine approved specifically for monkeypox.

However, along with awareness and appropriate caution, “[Vaccination is] key to reining this in and getting it under control,” says McCollum.

Was this international outbreak unexpected?

Experts did not predict that monkeypox “would move through closely related social networks and across borders in the numbers that we’re seeing right now,” says McCollum.

But there were warning signs.

In Africa, monkeypox cases began increasing after smallpox was globally eradicated in 1980 and vaccination campaigns ended: those vaccines cross-protected against all orthoviruses. As leftover immunity wanedmonkeypox infections jumped, rising 20-fold from 1986 to 2007 in DRC.

The first outbreak in the Western Hemisphere occurred in 2003 when a shipment of exotic pets—Gambian pouched rats, dormice, and squirrels—from West Africa sparked 47 human infections in the U.S. 

Then, in 2018, officials tallied growing travel-related cases. “That raised our eyebrows,” McCollum says. “We were becoming quite concerned that it was the tip of the iceberg.”

Underlying environmental conditions were ripe for this to happen, says Lewis. She lists factors that increase risk of zoonotic diseases passing from wildlife to people: climate change and deforestation that open access to the forest, the need for protein, and sale of bush meat in markets.

“We all share one planet,” she says, and we need research that helps us protect humanity and nature. “As long as we don’t have both those objectives in mind, we are going to keep getting into trouble.”

Here’s Everything You Need To Know About The Monkeypox Outbreak

(Update 8/9/2022)

With anxiety, frustration, and “pandemic fatigue” remaining at high levels after two and a half years of watching COVID disrupt everything – from businesses to education to travel and much more – it is understandable that many people are worried that we are in the early stages of the next pandemic with the current monkeypox epidemic. Especially considering the regular headlines, the unusual name, and the recent World Health Organization (WHO) designation of monkeypox as a “public health emergency of international concern” (PHEIC).

It doesn’t help that former U.S. Surgeon General Dr. Jerome Adams, who presided over the nation’s initial response to the COVID pandemic, recently induced some panic when he tweeted, “I hate to tell you all this, but #covid19 is still a pandemic, and now #monkeypox is too. And both are gonna get a LOT worse before they get better… just wait till schools – including colleges – reopen in a few weeks…” before later admitting that this is not actually the case.

Given how new and unexpected the monkeypox outbreak is, we all have many questions: Is there any justification to panic over the monkeypox outbreak? Is monkeypox the next COVID? Will it lead to thousands or millions of deaths? Will there be any need to impose mandates or restrictions on most of society to control the epidemic? Who is at risk? How do we control it?

To understand the answers to these questions, it is necessary to understand what monkeypox is as well as what it is not. Monkeypox is a member of the pox family of viruses, which includes the now-eradicated smallpox as well as the vaccinia or cowpox virus, which would confer immunity to smallpox to those it infected. Since it was first discovered in humans in 1970, over 50 years ago, monkeypox has been largely confined to West Africa, where humans interact closely with non-human animal reservoirs of the virus (which, incidentally, tend to be rodents, not monkeys). The monkeypox virus is known to spread from one human to another via prolonged skin-to-skin or other intimate contact. Unlike SARS-CoV-2, the virus that causes COVID, it is not a respiratory pathogen, which means monkeypox is not thought to spread via inhalation of the same air or respiratory droplets that are released during a sneeze or cough.

After a five to 21-day incubation period, an illness typically lasting between two and five weeks may begin. Initially, monkeypox-infected individuals develop flu-like symptoms, including: muscle aches, fever, swollen lymph nodes, and fatigue. These early symptoms are then shortly followed by a rash resembling chickenpox, which typically originates in the face and eventually spreads outward to the hands and feet. While mortality has historically been low with monkeypox, at around three to six percent of cases (and with young adults and immunocompromised individuals at higher risk of severe disease), common complications can include respiratory distress and even blindness.

In 2003, a monkeypox outbreak occurred in the United States, originating from infected prairie dogs that were housed near animals imported from Ghana, that infected 47 people. During this outbreak, all cases were attributable to animal-to-human transmission from close handling, bites, scratches, and cleaning the cages of sick animals. The outbreak was contained by quickly identifying the source and administering smallpox vaccines (which have cross-reactivity with monkeypox) to at-risk individuals. No deaths occurred in that outbreak.

The 2022 monkeypox outbreak, however, has now arguably evolved into a global epidemic. At the time of this writing, there are over 25,000 global confirmed cases, and the United States has over 6,000 confirmed cases in 49 jurisdictions, with the highest case counts being in New York state and California. Thus far, among these cases, there have been no reported monkeypox-associated deaths in the United States. Brazil and India have each reported one death, with the Brazil patient being immunocompromised and having lymphoma. Spain has also reported two deaths. With a reported death rate in the current monkeypox epidemic far below the three to six percent previously reported, there is low concern for mortality, but there remains a risk for other complications of the infection.

We have also amassed a great deal of information regarding who is at risk. As of August 2, California’s Department of Public Health has reported that among its approximately 1,135 statewide cases of monkeypox, 14 have been hospitalized for the infection, with the vast majority of patients being aged between 25 and 44 years. From among the monkeypox cases with available data, 98.8% have been reported in male or transgender male individuals, with 97.2% of infected individuals identifying as gay, lesbian, or bisexual. Given this information, California’s public health website states: “While it’s good to stay alert about emerging public health outbreaks, the current risk of getting monkeypox in the general public is very low.”

The WHO and Centers for Disease Control (CDC) have taken a different approach to the monkeypox outbreak than they did with COVID, electing to adopt recommendations directed at the individuals and communities at greatest risk, rather than issuing broad restrictions that impact the entire public. The WHO, in addition to declaring monkeypox a PHEIC, recommended that men who have sex with men limit their number of sexual partners, while the CDC has chosen to issue “safer sex” recommendations that deliberately avoid singling out any groups to avoid stigmatization.

At this point in the monkeypox epidemic, when case numbers are relatively few and infections are concentrated among well-defined communities, we have a unique and narrow window of opportunity to adopt lessons we have learned from the COVID pandemic and enact focused protection of those who are at risk to both protect those individuals and halt the broader spread of the virus. Focused vaccination programs, educational campaigns regarding safe practices, and temporary limitations on specific events that are likely to lead to further spread of the monkeypox virus should all be considered. We learned from our initial response to the AIDS epidemic in the 1980s that we can do so while being respectful to impacted communities by focusing our language on medical risk reduction, rather than shaming individuals for their identities or personal practices. Any efforts to avoid focused protection of at-risk communities out of fear of stigmatization will cause public health agencies to squander this opportunity to contain the spread of monkeypox, effectively worsening its impact and potentially making it far more difficult to control in the future.

Given how skeptical the public has become after watching public health and political leaders make one harmful mistake after another in their attempt to manage the COVID pandemic, leaders must now set aside politics and political correctness and very transparently employ the clinical evidence about monkeypox to address this epidemic swiftly, before it spreads beyond its existing pockets. Time is running out.

Why monkeypox cases are still rising at such an alarming rate

The U.S. had tools to contain this virus, which is far less contagious than COVID-19. So what went wrong?

(Update 8/15/2022)

Unlike COVID-19, the monkeypox virus requires intimate, often skin-to-skin contact with an infected individual’s rashes, scabs, bodily fluids, or contaminated linens to spread. So with at least some known transmission routes, available diagnostic tests, and two vaccines on offer, monkeypox should have been easy to manage in the United States.

And yet cases—most among men who have sex with other men—are still rising at such an alarming rate that the federal government has now declared monkeypox a public health emergency, leaving many people baffled about what went wrong.

Since May more than 80 countries where monkeypox is not endemic have reported nearly 28,000 cases, including about 7,500 in the U.S. All states except Montana and Wyoming have confirmed cases, but more than half have been recorded in New York, California, Illinois, Florida, and Texas.

Part of the problem is that “by the time we were aware of this [in May], there was already probably substantial transmission in the community,” says Wafaa El-Sadr, an infectious disease physician and epidemiologist at Columbia University in New York City. And according to public health experts, the ongoing crisis has been exacerbated by inadequate access to testing, misdiagnosis, limited availability of the vaccine, and—until very recently—a cumbersome prescription process for the only available antiviral drug.

“When you have an infectious disease that’s spread through contact and appears in a community where it circulates through social and sexual networks, and the main tool to prevent the spread—the vaccine—isn’t easily available, it’s not surprising we’re seeing the situation we’re seeing right now,” says El-Sadr.

Other contributing factors include poor understanding of suspected routes—such as sexual transmission via semen or vaginal fluids—and a lack of financial support for people who cannot afford to miss work. Infected individuals must isolate for 21 days; that can be a huge challenge, especially for low-income communities of color, undocumented immigrants, and transgender people who may already be struggling to access healthcare, says Jason Cianciotto, vice president of communications and public policy at the New York City nonprofit Gay Men’s Health Crisis.

It’s also possible asymptomatic or mild cases are going unnoticed, which might make current case counts a gross underestimate.

“We’re seeing cases that more likely have classic symptoms, but I suspect that there may be many more where the disease may be mild and the person gets better on their own or their case is misdiagnosed,” El-Sadr says. “I fear what we’re counting is likely the tip of the iceberg.”

But while the federal response has been slow, declaring monkeypox a public health emergency could help mobilize resources, streamline data collection, and cut through red tape so that states and local governments can better respond, according to some public health experts.

Where is the monkeypox vaccine?

A two-dose vaccine called Jynneos can be given to people exposed to the virus or at risk of getting infected. A single-dose vaccine called ACAM2000 is approved for smallpox and can be given for monkeypox, but the Centers for Disease Control and Prevention caution that the jab produces more adverse side effects, especially in immunocompromised people like those with HIV. Surveillance data from the U.S., England, and the European Union, indicated that in monkeypox cases in which HIV status was known, between 28 and 51 percent had HIV infections.

For the severely ill, some medical professionals are prescribing a smallpox antiviral called tecovirimat, or Tpoxx, that can be used to treat monkeypox.

Currently, though, the vaccine supply is nowhere close to meeting demand among the eligible population, which includes men who have sex with men, sex workers, and healthcare staff exposed to the virus.

San Francisco has been running through its allotted vaccines at a rapid clip, says the city’s health officer Susan Philip. At the Zuckerberg San Francisco General Hospital,the city’s only drop-in monkeypox vaccination site, “there are lines that stretch for several blocks when vaccines are available,” Philip says.

The situation is similar in New York City. “Amongst my friends, we jokingly consider it like a Hunger Games activity to try to get a vaccination slot,” says 28-year-old New Yorker William McChriston, who got his first monkeypox vaccine dose on July 24. The FDA has stressed administering the second dose 28 days after the first, but it’s unclear when McChriston will get his second dose because the city is prioritizing the first jab to get more people at least partially protected.

The supply problems create extra hurdles for people who aren’t digitally savvy and those who don’t readily have access to the internet or are working at 6 p.m., which is when appointments in New York go live and then get booked up within minutes.

“The virus is taking advantage of the runway that it’s been given, and I think we’ll continue to see a lot more cases,” says Anne Rimoin, an infectious disease epidemiologist at the University of California, Los Angeles, given the highly interconnected social and sexual network within which the virus is quickly spreading (although the virus can infect anyone who comes in close contact with an infected patient) and no prior immunity.

How does declaring a public health emergency help?

Although monkeypox doesn’t spread as easily as SARS-CoV-2, the virus that causes COVID-19, the emergency declaration “enables people to pay attention to it,” says El-Sadr. It could also allow for governments at different levels to work together, share information, and potentially tap into additional resources.

For now the emergency announcement doesn’t legally bind state or federal agencies to provide certain cities or jurisdictions with more vaccines, Philip says, but “we’re making the case for it.”

On July 28 the U.S. Department of Health and Human Services announced plans to allocate 786,000 doses of the Jynneos vaccine in addition to the 340,000 that had already been distributed. Their plan is to prioritize areas that have large at-risk populations and high numbers of new cases. “The strategy ensures that jurisdictions have the doses needed to complete the second dose,” according to an HHS press release.

In New York, the emergency declaration extends the pool of personnel who can administer the monkeypox vaccines to include emergency medical service workers, pharmacists, and midwives. Similar to California, it will also mandate that healthcare providers send vaccination data and potentially antiviral prescription data to the state health department.

These data would help public health managers understand how many courses of antiviral medication are being given, where vaccine demand is high, who is getting vaccinated, and how many people come seeking evaluation and testing, Philip says.

So far, the majority of infected individuals are men who have sex with other men, and many are people of color. A recent CDC report revealed that 58 percent of the nearly 1,300 U.S. monkeypox patients who provided data on their race and ethnicity were either Hispanic or Black.

As more people get tested, vaccinated, and use the antiviral Tpoxx, there’s an opportunity to understand even more about this monkeypox strain, which is endemic to West Africa, and how well the treatments currently in use work against it.

Until now, the effectiveness of the Jynneos vaccine and the Tpoxx antiviral have only been formally tested in animals because human trials were either unfeasible or unethical. Real-world data will allow scientists to study how well these therapeutics work, how much immunity a single dose imparts compared to two doses, and the extent to which Tpoxx limits the virus’s spread in the body and contains symptoms, says Amesh Adalja, an infectious disease expert at Johns Hopkins Center for Health Security. “That data collection is happening to some degree,” Adalja says.

The National Institutes of Health will also be testing another injection strategy to stretch the limited vaccine supply by administering smaller doses of Jynneos into the skin rather than under the skin, which is current practice.

There’s also an opportunity to fill in gaps in our understanding about how the virus spreads. A recent study found monkeypox DNA in the semen, saliva, urine, and feces, of some infected individuals. Whether the virus remains infectious in bodily fluids is unclear, although a study published on August 2 suggests that the semen of monkeypox patients could be a source of infection spread.

“Same goes for the risk of transmission from surfaces and respiratory droplets,” El-Sadr says. “We have an endless list of the questions, and this is the moment to mobilize research funding to answer these questions as quickly as possible.”

Resources

nature.com, “Monkeypox outbreaks: 4 key questions researchers have Scientists are racing to understand the latest monkeypox outbreaks — from their origins to whether they can be contained.” By Max Koxlov; natinalgeographic.com, “Monkeypox cases are rising—here’s what we know so far: An outbreak of monkeypox, which is related to smallpox, has public health officials concerned. But the virus can be contained with vaccines that are already stockpiled and available in some countries.” BY PRIYANKA RUNWAL; CDC.gov, “Monkeypox.” by CDC editors; nationalgeographic.com, “How contagious is monkeypox—and should you get a vaccine? Here’s the latest. The disease is now global and is spreading rapidly, but there are simple ways to lower your risk of infection. Here’s what you need to know.” BY SHARON GUYNUP; dailywire.com, “Here’s Everything You Need To Know About The Monkeypox Outbreak.” By Houman David Hemmati; nationalgeographic.com, “Why monkeypox cases are still rising at such an alarming rate: The U.S. had tools to contain this virus, which is far less contagious than COVID-19. So what went wrong?” BY PRIYANKA RUNWAL;