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.
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:
- Muscle aches
- Swollen lymph nodes
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:
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.
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.
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 chimpanzees. Recently, 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 Africa—provides 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 monkeypox. A 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.”
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;