Mpox cases are rising, and it's important to know what to do if you think you have it or know you've been exposed to it.

"We're still learning more about this virus," says Dr. William Miller, an infectious disease specialist at Houston Methodist. "It's behaving a bit differently from previous outbreaks, with the primary mode of spread identified to date being through intimate contact with someone who is infected."

It is important to know that anyone can get mpox. The current outbreak is a legitimate public health concern — the Biden administration has declared it a public health emergency — so we should all take the illness' spread seriously. While not usually fatal, the viral infection can cause a very painful and contagious rash.

Here's how to tell if you might have mypox, as well as what to do next.

What are the symptoms of mpox?

Whether you've had a potential exposure or not, it's important to know what to be on the lookout for.

Mpox symptoms include:

• Fever
• Intense headache
• Muscle aches
• Fatigue
• Swollen lymph nodes
• Skin rash or lesions

All but the skin rash are considered prodromal symptoms — meaning symptoms that appear before the onset of the illness' characteristic signs. The rash, the most prominent symptom, in previous outbreaks usually began one to three days after the development of the fever. That's the most common scenario with this outbreak too, but in some cases the rash is presenting at other times.

"What's different about this particular outbreak is that the rash can start prior to prodromal symptoms," explains Dr. Miller. "We're also seeing cases where all symptoms start at the same time or a person develops the rash but none of the prodromal symptoms."

People who have mpox are considered infectious beginning with the onset of symptoms. They remain infectious until a fresh layer of healthy skin has formed underneath lesions that have crusted and separated. That process can take two to four weeks.

How do you know if you've been exposed to mpox?

Knowing whether you may or may not have been exposed starts with understanding how mpox spreads from an infected person to an uninfected person.

The mpox virus can be transmitted via:

• Direct contact with the infectious rash, scabs or body fluids
• Indirect contact by handling bedding, towels or clothing that have come into contact with the infectious rash, scabs or body fluids
• Prolonged face-to-face contact through respiratory secretions

Of these possible modes of spread, Dr. Miller adds that direct contact — typically during close physical contact — with the infectious rash or secretions represents the primary concern.

"If you've had intimate contact in the last 21 days with someone who develops a mpox-like rash or has been diagnosed with mpox, you may have been exposed," explains Dr. Miller.

Additionally, since the scabs and lesion fluids can carry infectious particles, indirect contact through shared pillows and bedding is another potential concern. So is cleaning these items, if you're not taking caution to keep infectious particles from being dispersed into the air.

"Dusting and vacuuming can stir up these infectious particles, so we recommend wet cleaning surfaces that might contain them," explains Dr. Miller. "Remove bed sheets gently — don't rip them off since this can also disperse particles into the air."

And while face-to-face transmission via respiratory secretions isn't as big a concern with mpox as it is with COVID-19, it's still possible if exposure is prolonged and close.

What should you do if you've had a potential or known mpox exposure?

"There are different risk stratifications for exposure, some being higher than others, so it's really important to contact your healthcare provider if you think you've been exposed," explains Dr. Miller.

Your provider can advise you on what you, specifically, should do next.

Those next steps may include one or more of the following:

• Monitoring for mpox symptoms and avoiding sexual contact for the next 21 days
• Isolating and getting tested if you develop symptoms
• Receiving post-exposure prophylaxis if you had higher risk contact

The sooner you contact your healthcare provider with your exposure concerns, the better.

Quickly ruling out or confirming a mpox diagnosis doesn't just help limit spread, it may also help reduce your symptoms if you do indeed have it.

"Post-exposure prophylaxis via vaccination is most effective when given within the first four days of the exposure," says Dr. Miller. "And while vaccination after four days may not prevent the illness, it can help reduce the severity of it."

What should you do if you develop a mpox-like rash?

Anyone who develops an unexplained rash, especially if it's accompanied by fever or swollen lymph nodes, should contact their healthcare provider, even if they don't think they've had contact with someone who has mpox.

"Your provider can help you understand where and how to get tested," explains Dr. Miller. "Testing is important because it can help rule out or confirm a mpox diagnosis and help prevent further spread of the illness."

The CDC has shared images of what the rash can look like during the current mpox outbreak.

What should you do if you have mpox?

If you're diagnosed with mpox, you'll need to isolate and avoid having physical contact with other people.

"Again, the infectious parts of the virus can spread from the rash, secretions and scabs," Dr. Miller adds. "So, in addition to not having direct contact with other people, avoid sharing bedding, clothing or eating utensils."

If you do have to be around others, Dr. Miller recommends ensuring the areas of rash are covered. He also recommends being cautious and wearing a mask if you can.

"In previous outbreaks, spread by respiratory secretions occurred after prolonged close exposure, but if you're going to be close to others, it would be best to wear a mask to really limit any chance of spread by this route," explains Dr. Miller.

It's also important to monitor your symptoms and reach out to your healthcare provider if they worsen.

Mpox is typically self-limiting, and the symptoms often resolve on their own after two to four weeks without the need for medical care.

"Some people may benefit from treatment, however," says Dr. Miller. "The lesions can be very painful and, anytime you have a rash like this, secondary infections are possible — and medications may be needed in either of those cases."

This post was updated on May 20, 2024 to reflect the new nomenclature of the mpox virus.