How do humans get monkeypox?

Aug. 5, 2022
Photo of a woman talking about human monkeypox
Colorado has its first confirmed case of human monkeypox. Photo courtesy World Health Organization.

The World Health Organization and the Biden Administration have declared monkeypox as a public health emergency. The Colorado Department of Public Health and Environment is monitoring the number of cases in Colorado.

The monkeypox virus long has been endemic in parts of central and western Africa, but after cases were discovered in European and North American nations, public health organizations sounded alerts around the world. The  Centers for Disease Control and Prevention alerted gay and bisexual men that monkeypox appears to be spreading in the community globally, warning people to take precautions if they have been in close contact with someone who may have the virus and to be on the lookout for symptoms. The CDC makes it clear, however, that the risk is not limited to the gay and bisexual community.

To answer your questions about monkeypox, we consulted with Dr. Michelle Barron, senior medical director of infection prevention and control at UCHealth University of Colorado Hospital on the Anschutz Medical Campus.

What is monkeypox?

Monkeypox is a virus that spreads from animals to humans, so it is called a zoonotic disease. Researchers first identified the virus in1958 in monkeys used for research. That’s how monkeypox got its name. But monkeys aren’t the most common carriers of the disease today. Rodents, like squirrels, can transmit monkeypox. Humans can get it if they get bitten by an infected animal or they touch the animal’s fur or bodily fluids.

Dr. Michelle Barron

How does monkeypox spread from human to human?

Typically, human monkeypox spreads through very close, intimate contact, and it also can be spread through droplets.

“If someone coughed or sneezed, or you had direct contact with the rash, it potentially could be transmitted that way,” said Barron, who is also a professor at the University of Colorado School of Medicine.

“With physical contact, you would actually have to touch somebody’s lesions or rash to potentially be able to transmit it.”

How concerned should people in Colorado be about monkeypox now?

“It’s more likely that you are going to get the flu than you are going to get monkeypox,” Barron said. “Or you are going to slip and fall on your hike and have an accident that way.”

“Awareness of your skin is always important. Especially living in Colorado, with the incidence of skin cancers that probably get missed, it’s good to look at your skin. If you see something that looks funny, go to your doctor or go to your dermatologist.”

What are the symptoms of monkeypox in humans?

“People will have flu-like symptoms. They might have fever or chills, body aches, maybe some swollen lymph nodes and then they get a characteristic rash. It looks like nothing else; it is not easily confused with a lot of other rashes. It’s raised, it’s hard, it’s firm and it looks like it has a little divot in it. And when you see this, you say: ‘I’ve never seen anything like this.’”

Barron said the rash typically is not painful but, with the current outbreak, about half the people don’t appear to have flu-like symptoms before they notice that they have a rash.

Is there a specific time when it is more contagious?

“The incubation period is somewhere between three and 16 days. People are most infectious when they have the rash itself,” Barron said. “So, when you come into contact with that rash, it doesn’t mean that you are necessarily automatically going to get infected but your risk is highest when the rash is there, until it scabs or completely falls off.”

How long does monkeypox last?

The illness typically lasts 2-4 weeks. In Africa, the disease causes death in one in 10 people who get the disease, according to the Centers for Disease Control and Prevention. In mid-September, the Los Angeles Department of Public Health, along with the Centers for Disease Control and Prevention (CDC), confirmed the first death due to monkeypox in a Los Angeles County resident.

Is there a treatment for monkeypox?

No, there is no proven treatment for monkeypox infection. If transmission of the virus became more widespread in the United States, smallpox vaccine, antivirals, and vaccinia immune globulin (VIG) can be used, according to the CDC.

What should you do if you come into contact with someone who has monkeypox?

“If you think you have come into contact with someone who has monkeypox, obviously you want to be looking and examining your skin quite well,” Barron said. “The other thing is to call your physician or your provider to see if there is something else that we can do for you, depending upon the circumstances or the kind of exposure.

“The biggest thing is that you have awareness about this. If you see this rash and you don’t know what it is, you want to make sure that you pay attention and you don’t just ignore it and that you have a doctor examine it. The rash can appear anywhere on your body — it could be on your hands, it could be on your chest, it could be on your genital areas, it could be anywhere.”

Can people be protected from monkeypox?

“Monkeypox is a cousin of smallpox or cowpox. It is thought that perhaps if you have had smallpox vaccinations that there is enough overlap to what it looks like to your immune system, that you would be protected against it,” Barron said.

“And certainly, if there was a huge outbreak of monkeypox that was of concern, we could potentially offer smallpox vaccines,” she said. “Right now, it is probably not on that scale. And again, most of the cases so far seem to have overlap in certain countries and/or men that are having sex with men.”

Because of COVID-19, are people more aware of public health messages?

“People have become hyperaware of all of these infectious diseases that occur, and that’s not actually a bad thing,” Barron said. “You want to be aware of the diseases that are out there so that you can protect yourself or know what it looks like so that if you think you have it, you can actually seek help.”

At the same time, Barron encourages people not to get panicky about rare infectious diseases like monkeypox.

“The hyperawareness in public health is something that we’ve never had before, and everybody has the opportunity to dial it down if they need to,” Barron said. “That doesn’t mean to completely ignore messaging, but I don’t think every time you hear something about public health on the news that you need to panic. It may just be more of, ‘OK, my chances of getting this are zero, so I’m good.’

“Or, I have Jif peanut butter in my cupboard, and there’s been a salmonella outbreak associated with that right now. Maybe I should look at the label. Peanut butter can last in your cupboard for a long time, and you might never even think about it. So, you can decide how to scale that message in a practical way.”

If I pass someone in the hallway, is that exposure?

“If you are not acquiring monkeypox when you have contact with an animal, and the transmission is from human to human, it has to be prolonged, intimate contact. So, sleeping next to someone or being very close, where skin is touching is the key, whereas, if you are walking in the hallways or otherwise, it is so unlikely that that would occur,” Barron said.

At what point should someone see a physician about this?

“Right now, the current recommendation is if you have either had contact with someone that is known to have a diagnosis of monkeypox, or you have traveled to one of the countries in the United Kingdom, Canada, Portugal, or Spain that are having outbreaks and you engaged in activities that could potentially put you at risk for contact with someone who has it, and you have the characteristic rash, you should see a doctor,” Barron said.

About the author

Erin Emery is editor of UCHealth Today, a hub for medical news, inspiring patient stories and tips for healthy living. Erin spent years as a reporter for The Denver Post, Colorado Springs Gazette and Colorado Springs Sun. She was part of a team of Denver Post reporters who won the 2000 Pulitzer Prize for breaking news reporting.

Erin joined UCHealth in 2008, and she is awed by the strength of patients and their stories.