A senior adviser for the World Health Organization has said the monkeypox outbreak seems to be spreading through sexual contact, and warned that case numbers could spike over the summer months as people attend major summer gatherings and festivals.
David Heymann, chair of the WHO’s Strategic and Technical Advisory Group on Infectious Hazards with Pandemic and Epidemic Potential, led a meeting of the group on Friday “because of the urgency of the situation”.
Heymann told Reuters the WHO is working on the theory that cases so far identified were driven by sexual contact.
“What seems to be happening now is that it has got into the population as a sexual form, as a genital form, and is being spread, as are sexually transmitted infections, which has amplified its transmission around the world,” Heymann said.
Heymann, a professor at the London School of Hygiene and Tropical Medicine, said experts were likely to give more guidance to countries in the coming days. Health officials in several countries have warned that cases could rise further over the summer.
Heymann said the monkeypox outbreak did not resemble the early days of Covid because it does not transmit as easily. “There are vaccines available, but the most important message is: you can protect yourself,” he said.
The warning comes as a New York City resident has tested positive for the virus that causes monkeypox, health officials said, with the federal Centers for Disease Control investigating to determine whether the rare disease is actually present.
Officials are treating the case as positive, and they have placed the patient – whose identity was not released – in isolation as they awaited final confirmation of the test result from the CDC.
The notification came a day after authorities in New York City said they were investigating two potential cases. One of those potential cases in the city was ruled out, the state health department said.
City epidemiologists have begun contacting people who may have been exposed to the person infected with Orthopoxvirus, the family of viruses that includes monkeypox. State and city officials have said they will try to determine how the New York patient was infected.
The virus comes from wild animals, including rodents and primates, but can occasionally transfer to humans – with most of those cases traced to central and west Africa. The first known human infection dates back to 1970, when a nine-year-old boy in a remote part of DR Congo was diagnosed with the virus, which can cause fever, body aches, chills and fatigue.
People with severe cases can also develop rash and pus-filled lesions on the face, palms of the hands and other body parts.
The virus does not spread easily between people, though officials have said transmission can occur through contact with body fluids, monkeypox sores, items that have been contaminated with fluids or sores such as clothing and bedding, or through respiratory droplets following prolonged face-to- contact side.
The apparent infection in New York comes as the WHO has identified about 80 cases globally, along with roughly 50 more suspected cases. The WHO warned more cases are likely to emerge.
Infections have been confirmed in nine European countries, as well as the US, Canada and Australia.
Health officials in Massachusetts confirmed its first case of the disease on Wednesday. Officials in the state have said the patient recently traveled to Canada.
“The current patient is of no public health risk right now,” Dr Paul Biddinger, director of the Center for Disaster Medicine at Massachusetts general hospital said on Thursday. “People should just be aware of symptoms, but not be afraid in any way.”
Cases of monkeypox periodically show in the US. Last year, Texas and Maryland each reported a case in people who had recently traveled to Nigeria. In 2003, there was a six-state outbreak that infected 47 people.
“Monkeypox is not a monkey virus,” D. Matt Aliota, head of the University of Minnesota’s Program of Zoonotic Viral Infections, told Minnesota’s Kare11 last week. “It was originally isolated out of a monkey, but monkeys aren’t the natural host.
“It’s a virus that naturally infects small rodents and can then jump to humans through scratches or hunting and processing of meat.”
In recent days, clinicians have been advised to treat patients with related symptoms as a “possible diagnosis” and to consult their state health department or the CDC’s Emergency Operations Center “as soon as monkeypox is suspected”.
The advisory also gives infection control information to healthcare providers.
Health officials have also made it a point to note that the monkeypox is harder to transmit – and therefore easier to contain – than the coronavirus.
People who are exposed to monkeypox, which has a slow incubation period, can be given smallpox vaccines already in circulation to curb the severity of the sickness, according to the CDC.