UMonkeypox spread very rarely from person-to-person, even though it was widespread up until recent years. In 2005, a study declared a cluster of six cases in the Republic of Congo “the longest uninterrupted chain of human monkeypox fully documented to date.”
This has all changed. So far this year, more than 25,000 monkeypox cases have been recorded across 83 countries—and human-to-human transmission is clearly happening at large scale.
Is monkeypox spreading among people? The research is ongoing and new findings regarding monkeypox transmission could emerge over the years. But here’s what the latest science suggests.
The majority of cases are now linked to infected animals
According to the World Health Organization, (WHO), the first case of monkeypox in humans was found in a child in the Democratic Republic of the Congo. It occurred in 1970. Cases were very rare over the next decades, often due to close contact with infected animal. A small epidemic occurred in the USA in 2003. There were 47 confirmed cases.
In 2017, a large-scale human epidemic in Nigeria began. Doctors there diagnosed cases among young men who hadn’t been exposed to infected animals and had lesions on their genitals, as NPR reported. Nigerian scientists published a study in 2019 on the issue and suggested that sexual transmission could be possible. However, the theory was not well received at the time. “There’s a tendency for people to latch [onto] what is tradition, and the tradition is that monkeypox is transmitted from animals to humans,” says study co-author Dr. Dimie Ogoina, president of the Nigeria Infectious Diseases Society.
Many cases of monkeypox in this ongoing epidemic are linked with sex.
As the current outbreak shows, human-to-human transmission of monkeypox does happen—and sexual activity plays a significant role.
“Right now, most transmission is occurring in queer and gay sexual networks, and most transmission is occurring through sexual or intimate contact,” says Joseph Osmundson, a clinical assistant professor of biology at New York University.
Ogoina says monkeypox primarily spreads among humans through close, skin-to-skin contact—especially with the disease’s hallmark blister-like rash. Although it is not known if people are asymptomatically contagious or not, researchers are continuing to study the possibility. However, individuals can still be considered infected until they have fully healed and new skin forms, according U.S. Centers for Disease Control and Prevention.
The July issue of the Journal published a study about the current epidemic. New England Journal of MedicineAccording to the study, out of over 500 cases of monkeypox across 16 different countries, 95% could be linked to sexual activity. The remaining 98% were associated with men having sex. Tedros Adhanom Ghebreyesus, WHO Director General, advised men who sex with women to reduce the number of their partners temporarily to decrease their chance.
What is the sexually transmitted disease (STI) monkeypox?
Any form of skin-to-skin contact—not just sexual activity—can potentially spread monkeypox. As a result, monkeypox is not considered a “traditional” STI, according to Dr. Roy Gulick, chief of infectious disease at Weill Cornell Medicine and NewYork-Presbyterian. Also, the CDC states that monkeypox cannot be considered as an STI.
Most cases in the current outbreak have been linked to male sexual activity, but Osmundson says the virus could also spread in settings where there’s lots of close non-sexual contact, such as on sports teams, in spas, or in college dorms.
Are surfaces capable of giving you monkeypox?
It is possible to contract monkeypox through exposure to items, such as clothing or bedding, that have touched an infectious person’s rash. In 2018, a health care worker in the U.K. contracted monkeypox most likely after handling a sick person’s bedding, according to one study.
But there’s little evidence to suggest that “incidental” contact frequently spreads the virus, says Angela Rasmussen, a virologist at the University of Saskatchewan in Canada. “You have to be exposed to enough virus to actually get infected with it,” she says. That might be possible after sleeping in the same bed or sharing a bath towel with an infectious person, but it’s much less likely after fleeting encounters like touching a shared doorknob, she says.
With the vast majority of cases so far linked to sexual activity, it’s important to communicate that there is a “spectrum” of risk associated with monkeypox, says Dr. Müge Çevik, a clinical lecturer in infectious diseases at the University of St. Andrews in Scotland. “Every single exposure [doesn’t carry equal] risk,” she says. “People really need to know where to be vigilant. This includes reducing new [sexual] partners may be more useful than cleaning chairs you’re sitting in in a coffee shop.”
Is monkeypox airborne?
It’s possible to catch monkeypox through exposure to an infectious person’s respiratory fluids, but the WHO says that usually requires close, sustained face-to-face contact. According to the CDC, researchers are still trying to determine how frequently this type of transmission happens.
Scientists have demonstrated that it is possible, under specific experimental conditions, for monkeypox to spread via aerosols, or tiny particles that can stay suspended in the air—but so far, there’s not strong evidence to suggest that’s happening under real-world conditions outside of the lab, Rasmussen says. “This is spreading primarily in communities of men who have sex with men, and that really suggests the primary mode of transmission is direct, prolonged skin-to-skin contact,” she says. We would see more cases of airborne transmission if it were widespread, she states.
People are concerned that monkeypox could be transmitted via aerosols, as they live in the shadow of COVID-19. But ”the epidemiology is very different,” Rasmussen says. “These are very different viruses.”
Can kids get monkeypox?
The virus has infected more than 80 children worldwide. This is mainly due to household transmission. The CDC states that pregnant women may also transmit the virus through their fetus.
In the 1970s, monkeypox mostly affected young children—but by the 2010s, the virus was more frequently diagnosed among adults, according to a study published in PLOS Neglected Tropical Diseases It was February. That’s in part because routine smallpox vaccination (which also protects against monkeypox) ended as smallpox was eradicated, the study’s authors write. Only a few decades ago, smallpox vaccine was available to children under the age of five. Today, more of the population are at risk.
Concerns have been raised about the possibility that daycares and schools could be monkeypox hotspots due to pediatric cases. But Ogoina says that hasn’t happened during Nigeria’s outbreaks, which is a promising sign. “I’m not sure whether it’s something we need to worry about,” he says. “But we need to tread cautiously and look for the evidence.”
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