Medically reviewed by: Ted Schiff, MD
Even as the COVID-19 pandemic drags on, experts are tracking a new viral outbreak: monkeypox. The two viruses have little in common. One important difference: Monkeypox is not new, and according to the Centers for Disease and Prevention (CDC), an existing smallpox vaccine may be at least 85% effective against it.
The illness, which until now has been rare outside of Africa, is spreading in certain parts of the world, including Australia, Europe, Canada and the United States. Currently, the CDC says the risk to the general public is low, but vigilance is smart.
Here’s what you need to know about monkeypox and the symptoms to watch for.
What is monkeypox?
Monkeypox is a virus related to smallpox and cowpox. Smallpox, which was often fatal, was eradicated back in the 1970s with an aggressive global vaccination program. Cowpox is much milder and rare in humans.
The monkeypox virus appeared in 1958 in two groups of lab monkeys. Scientists aren’t sure what animal first developed it; it’s thought to be transmitted by rodents, not monkeys. The first known monkeypox case in humans occurred in 1970 in the Democratic Republic of Congo.
The virus can be passed from animals to humans — and also from humans to humans. Scientists say it’s not as easily transmitted between humans as the virus that causes COVID-19. Another positive: It’s not nearly as deadly as smallpox. According the CDC, monkeypox is fatal in 1% to 11% of cases. The strain thought to be circulating outside of Africa now appears to be a less dangerous one. No deaths have been reported to date.
A monkeypox infection usually starts with flu-like symptoms — fever, headache, muscle aches, fatigue — as well as swollen lymph nodes. Backache is also common. After one to three days, or sometimes more, a rash develops. The rash may appear on the face and then spread. The palms of the hands and the soles of the feet are common locations, though the rash can appear anywhere.
Flat, colored spots progress to small, firm, clearly defined bumps, which may have a depression in the middle. These bumps turn into blisters which fill with fluid and later, pus. They scab over, and eventually, the scabs fall off.
In monkeypox transmitted through sexual contact, the rash may appear on or near the genitals, as well as elsewhere. In these cases, monkeypox may skip the flu-like symptoms and start with the rash.
According to the CDC, symptoms usually show up about 5 to 13 days after infection, though it may take as long as 21 days. They last for two to four weeks.
How do you get monkeypox virus?
The virus is transmitted through close contact with an infected animal or human. Catching monkeypox from another person requires:
- Inhaling respiratory droplets, from an infected person’s cough, for example, or potentially, by spending three or more hours within six feet of an infected person without wearing an effective mask
- Coming into contact with bodily fluids, such as blood, saliva, blister fluid or blister pus, from an infected person
- Touching objects such as sheets or blankets that are contaminated with the virus
When airborne, the virus travels through large droplets, not the small particles that carry COVID-19. Large droplets typically can’t travel more than a few feet.
According to the World Health Organization, a number of the recent infections appear to have been sexually transmitted among gay and bisexual men during raves held in Spain and Belgium in early May. At least 30 cases in Spain have been linked to an adult sauna in Madrid.
There is no specific treatment for monkeypox, though antiviral medications developed for smallpox patients may help. The illness usually resolves on its own. In some cases, if a patient has been exposed to monkeypox, a doctor might administer a smallpox vaccine that is approved by the FDA for monkeypox in order to prevent monkeypox or lessen its severity.
People born in the United States before 1972 likely received a smallpox vaccination as a child. That vaccination should provide some protection against monkeypox.
If you have symptoms similar to those of monkeypox, especially if you’ve recently traveled to a country that has monkeypox outbreaks, had close contact with someone who has or may have monkeypox, or had intimate physical contact with other men, call your dermatologist or general practitioner to be evaluated.
Written by: Marianne Wait, an award-winning health and wellness writer based in New Jersey.