What are your chances of catching monkeypox?

What are your chances of catching monkeypox?

It's a question that many people are asking.

A global outbreak of this infectious disease began in May of this year and has spread to 50 countries – along with some inflammatory headlines and misinformation. While previous cases of monkeypox were typically transmitted from animals (mainly rodents) to people, it is clear now that most cases are the result of human-to-human transmission.

The concerns about catching monkeypox come at a time when the COVID-19 pandemic is still in force, with over 300,000 cases reported daily across the globe and over 10,000 deaths per week.

So how can people get a clear idea of what their chances are of contracting monkeypox?

Data for this current outbreak is preliminary and prone to underreporting (which is the case for many infectious diseases, including malaria, cholera and of course COVID-19). Not all states report comprehensive demographic information on monkeypox cases and testing availability to diagnose the disease is limited.

How we crunched the numbers

But there are ways to determine how much of a risk monkeypox poses to the general population and to certain segments of that population.

Risk of disease is typically expressed as 1 out of a larger number. For example, approximately 1 in 8 women are at risk of contracting breast cancer, which is a remarkably high risk factor. Such calculations are typically based upon data collected over the course of a year and in where the number of people contracting the disease is relatively predictable.

When a disease is contagious, the risks can be even higher – or can also be far lower, depending on many issues, like how it spreads.

We don't have a whole year's worth of monkeypox data to look over for this current outbreak. And global case rates were lower in May than they were in August. Since the latter month reflects current spread, we've restricted our monkeypox calculations to available data from mid-July through August when cases began peaking.

Working with Bill Jesdale, an epidemiologist at the University of Massachusetts Chan Medical School, we crunched the U.S. numbers available from the Centers for Disease Control and Prevention to give people a better sense of how to assess the potential impact of monkeypox on their lives. Then we looked at other more familiar diseases and threats so the monkeypox risks could be compared to COVID-19, death in a car crash and shark attacks, which of course are extremely rare (despite their prominence in the media).

What we know about monkeypox

Let's break it all down.

In this current outbreak, experts say that monkeypox is a disease predominantly spread through sexual networks of men who have sex with men. Gay, bisexual, and other men who have sex with men are the high-risk group, and of the roughly 8 million men who have sex with men in the U.S., approximately 1 in every 750 caught monkeypox in the month of August. That group is about 350 times more likely to catch monkeypox than women or heterosexual men who are a part of the low-risk group and whose chances of catching monkeypox last month were about 1 in 260,000.

Gay, bisexual and other men who have sex with men were also more likely to catch monkeypox in August than to have been hospitalized with COVID-19 if they were fully vaccinated or to have died in a car crash last year.

Monkeypox is mainly spread among sexual networks where individuals may have multiple sex partners. Indeed, the CDC estimates that half of monkeypox cases in the U.S. are spread through what it characterizes as "one-time sexual partnerships." So the risk is much lower for gay, bisexual and other men who have sex with men but do not have multiple partners or who are not sexually active.

And there are ways for the high-risk population to lower the risk. For men who have sex with men, the CDC says that reducing the number of sexual partners and one-time partnerships can greatly lower an individual's risk of catching monkeypox, according to a recently released study. Beyond that, getting vaccinated will also reduce your risk, though vaccination isn't 100% guaranteed to prevent an infection. The CDC (and other global health agencies) have additional information on how you can stay safe.

Now, if you're a parent who's worried about your children catching monkeypox, you can probably take a breather. The CDC reports that 17 children from ages 15 or younger have caught monkeypox in the U.S. last month — out of a population of over 60 million children. So the chances your child will catch monkeypox are about 1 in 3.5 million. That's more likely to happen than being attacked by a shark (roughly 1 in 110 million) but is still highly unlikely.

There is little available information about how those 17 children got monkeypox. In one New York City case, government officials suggest the child got monkeypox from an adult in their household who had the virus but additional details were not provided. Regardless, federal officials are finding that the cases happening outside of the high-risk group aren't leading to ongoing spread.

For people in Nigeria, where it's believed this outbreak of monkeypox began, only about 1 in 2 million people in the general population caught monkeypox from mid-July to mid-August. Even if you're not in the high-risk population here in the U.S., you're still at a higher risk than the average person in Nigeria. Officials from the Nigerian CDC claim that there is currently no evidence of ongoing sexual transmission of monkeypox in the country.

And it's clear when comparing monkeypox to COVID that most people still have a greater risk of being affected by COVID. The CDC estimates that more than half of the U.S. population has had a previous COVID infection. Your risk of being severely affected by COVID moving forward is dependent on your age, vaccination status, and whether you've had a previous infection, but there are still far more daily cases of COVID than there are monkeypox. Roughly 1 in 4,000 vaccinated individuals are ending up in the hospital with COVID each month. That's mostly people who are aged 65 or older. For those under 65 who are vaccinated, the risk of hospitalization is closer to 1 in 10,000.

Now with all that said, it appears that monkeypox cases in the U.S. are beginning to decline and that a slightly greater percentage of cases are occurring in people in the low-risk category for reasons that aren't yet clear. We took that into consideration during our consultation with epidemiologist Bill Jesdale, but he says that the modest shift in the demographic makeup of monkeypox cases is likely a result of how people are reporting their sexual orientation and behaviors — and that the way the disease is being transmitted has not changed.

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