Six Big Questions About the Monkeypox Virus, Answered

The United States recently declared the monkeypox outbreak a public health emergency. Here’s what you need to know about the disease

Monkeypox Vaccine
A registered nurse measures out a monkeypox vaccine in Miami, Florida. Joe Raedle / Getty Images

Monkeypox has become the latest public health emergency in the United States, but historically speaking, most Americans have not been familiar with the virus. Since monkeypox was first identified in humans in the Democratic Republic of the Congo in 1970, Africa has faced dozens of outbreaks. But monkeypox rarely spread outside the continent, aside from the 2003 outbreak that saw 71 cases in the U.S. Since May 19 of this year, however, over 18,000 monkeypox cases have occurred across the nation.

“We’re at a very precarious moment in this outbreak,” says Jay Varma, a physician, epidemiologist and director of the Cornell Center for Pandemic Prevention and Response. “Many of us had hoped that we wouldn’t be here because the U.S. had diagnostic tests, had a vaccine, even had drugs stockpiled.”

But this substantial preparedness gave way to a sluggish response that has been criticized by public health experts as flawed, woefully inadequate and the next public health failure.

As monkeypox has spread rapidly, so too have myths and misconceptions about the virus. Carlos Rodriguez-Diaz, an associate professor of prevention and community health at the Milken Institute School of Public Health at George Washington University, thinks that greater awareness and disease literacy is key to a more effective public health response. So, we reached out to medical experts to answer six key questions about monkeypox and the current outbreak.

How did monkeypox transfer to humans?

Monkeypox was first identified in captive monkeys stored at a Copenhagen research facility in 1958, but rodents—not monkeys—are thought to be the animal reservoir for this virus. The 2003 U.S. monkeypox outbreak likely began because Gambian giant pouched rats, dormice and rope squirrels, which had been imported from Ghana and carried the virus, were housed near prairie dogs that were subsequently sold as pets. As one example, three-year-old Schyan Kautzer got monkeypox after being bitten by her pet prairie dog. Kautzer survived; the prairie dog didn’t. Notably, this 2003 outbreak was not driven by human-to-human transmission, unlike today.

The strain of monkeypox currently spreading likely diverged from the 2018 to 2019 monkeypox variant in Nigeria, with several mutations making the virus even more transmissible. A possible “spillover” event, where monkeypox was transmitted from wild animals to humans, may have been followed by silent spreading among humans since 2018.

How does monkeypox spread?

According to the Centers for Disease Control and Prevention (CDC), monkeypox is typically transmitted through “close, sustained physical contact.” Roughly 99 percent of cases have been in men, with 94 percent reporting recent male-to-male sexual or close intimate contact. Black and Hispanic men have disproportionately borne the burden of disease with 54 percent of monkeypox cases compared to 41 percent among white men.

Yet despite the vast majority of cases being among men who have sex with men, Rodriguez-Diaz says, “this is not an infection that is specific for any group; it just affects humans. Right now, it’s affecting queer, bisexual, gay men.” A single point of entry, followed by super-spreader events (like two raves in Spain and Belgium), may have allowed the virus to quickly spread across the interconnected sexual networks of the men who have sex with men community. “The whole new outbreak could have started among heterosexual people and in heterosexual sexual networks,” Rodriguez-Diaz says, “but that’s not the case.”

Experts disagree whether monkeypox should be labeled a sexually transmitted disease or not, but the data are clear that monkeypox primarily spreads through sexual contact—likely via exchange of bodily fluids and skin-to-skin contact with lesions.

While monkeypox may also spread by touching contaminated objects, fabrics and surfaces, this type of transmission is extraordinarily rare, even for individuals living in the same household as someone with monkeypox. Varma notes that, for Americans who are not part of men who have sex with men social and sexual networks, “your risk is extremely low right now.”

What are the main symptoms, and how serious can it get?

The characteristic monkeypox symptom is a skin rash that initially looks like pimples or blisters. Over a two- to four-week infection period, these rubbery lesions progress through four key stages, from flat to raised to fluid-filled to pus-filled, before ultimately scabbing over. In a New England Journal of Medicine study of over 500 patients with monkeypox across 16 countries, 95 percent of patients presented with a rash, with over 70 percent reporting lesions near their genitals or anus—or inside their mouths.

Although around 15 percent of patients present with rashes alone, according to a study in the British Medical Journal, most patients also have flu-like symptoms, including headaches, fevers and swollen lymph nodes. While these symptoms typically precede the rashes, the course of infection can be highly variable, with 40 percent of patients experiencing them afterward.

Historically, monkeypox has had a 1 to 10 percent case fatality rate, but Varma notes that the present outbreak appears significantly less lethal. So, Americans, and particularly men who have sex with men, don’t need to worry much about monkeypox killing them. “Whether or not you suffer in pain so much that you feel like dying,” Varma adds, “that you should be worried about.”

What tests and treatments are available for monkeypox?

Initially, monkeypox testing was limited to 67 federal labs with a weekly capacity of 6,000 tests. But demand soon outstripped supply and created a bottleneck that fueled monkeypox’s spread: without adequate testing, the scope of the outbreak was obscured, and health professionals couldn’t easily identify and isolate patients. Varma says that testing availability has since improved, with the CDC partnering with five commercial laboratories to increase capacity to 80,000 per week, although he’s concerned that “the U.S. has not moved quickly enough to expedite the availability of testing sites other than the skin.”

Indeed, the current monkeypox test requires providers to swab external lesions. That makes it difficult to test individuals who develop flu-like symptoms first, have only internal lesions or never develop lesions at all. Given that monkeypox can potentially be detected in saliva and urine, Varma emphasizes the need for alternative testing modalities to expand access and capture a greater percentage of cases.

While no cure currently exists for monkeypox and no treatments are available specifically for the virus, four medications are being used to treat affected patients. These, however, have been difficult to access as well. For instance, in the strategic national stockpile, enough of the smallpox antiviral Tpoxx exists for 1.7 million patients, but physicians have been required to fill out 27-page applications to get access to this “investigational drug.” The CDC has taken steps to streamline the process, so treatment access should improve over the coming weeks and months.

The two available vaccines for monkeypox, JYNNEOS and ACAM2000, are thought to be at least 85 percent effective in preventing monkeypox. They can be used proactively or soon after exposure to prevent the disease altogether or to at least reduce symptoms. Unfortunately, ordering delays and other missteps by the federal government have led to a vaccine shortage and, yet again, limited access.

Should I get the monkeypox vaccine?

Per the current CDC guidelines, the only individuals eligible for vaccination are those who have been in close contact with someone who has tested positive for monkeypox or those with multiple recent sexual partners in an area with known monkeypox. This means that most Americans outside men who have sex with men communities are ineligible for vaccination since they are at low risk of contracting the virus. “Right now what we want to do is to contain the outbreak, and if we do that, nobody else will need vaccines,” Rodriguez-Diaz explains.

Because vaccine supplies are still insufficient for high-risk populations, the CDC has sought to stretch existing JYNNEOS vaccines by allowing skin injections using one-fifth of the usual dose. While Rodriguez-Diaz is cautiously optimistic about how this decision will improve access, he is concerned about the insufficient data in support and the challenges of actually implementing this less common immunization method. Namely, healthcare providers would need to be trained on how to give injections into the skin instead of the muscle or subcutaneous tissue, and small mistakes in dosage and injection depth could quickly add up to reduce protection against monkeypox.

More generally, Rodriguez-Diaz is worried about vaccine delivery because doses are less accessible outside urban centers and because appointment systems have contributed to racial disparities in vaccine access. He says that more equitable state-by-state vaccine distribution and walk-in vaccination clinics might be initial steps to resolve accessibility issues.

Should I worry about monkeypox becoming a pandemic?

Given the traumatizing experience of Covid-19, Varma understands why individuals might worry that monkeypox will become the next pandemic, but he thinks it’s unlikely given that the virus is not efficiently spreading outside sexual networks. But Varma does think monkeypox will become endemic—or, in other words, a permanent fixture in the U.S.

While Rodriguez-Diaz thinks the public shouldn’t yet worry about that, both he and Varma acknowledge that health professionals still don’t know a lot about the virus. They don’t know if monkeypox will ultimately start transmitting outside sexual networks. They don’t know if monkeypox will establish itself in animal reservoirs in the U.S. They don’t even know if asymptomatic patients spread monkeypox.

What is clearly apparent, however, is that the U.S. needs a more robust public health infrastructure to better contain infectious diseases. State and local health departments are the backbones of the public health system, yet they are overworked, underfunded and understaffed. “The single most important thing you can do,” Varma says about how the public can help stop the spread of monkeypox, “is get your elected officials to care about this. If they care about it, they will build the systems that will make it easier for all of us to live healthy lives.”

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