3 Signs It’s Time to Start Worrying About a Mosquito Bite
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It wasn’t until after Marshana Dahlia Spavento, 43, finished devouring her falafel and hummus at an outdoor restaurant in Miami that she noticed the 52 bites on her legs. (Yes, she counted them.) She pulled up her midiskirt and realized that mosquitoes had turned her limbs into a bloody buffet. “I feasted on feta and the mosquitoes feasted on me,” Spavento tells SELF. She broke into a fever later that night as her legs became really swollen and hot. It took two weeks for the swelling and itching to subside, and six months for all the marks to fade away.
Spavento was used to having dramatic reactions to bites; they’d grow as big as golf balls and were always red, hot to the touch, and unbearably itchy. But that night in 2017 was unlike anything she had ever experienced. “That was absolutely the last straw that prompted me to see my dermatologist,” Spavento says. She was diagnosed with skeeter syndrome—yes, that’s a real medical diagnosis—which is a relatively rare allergy to proteins in mosquito saliva that can be extremely painful, and, in some cases, so bad it can be mistaken for (or lead to) serious skin infections.
Now Spavento has no choice but to douse her skin in mosquito repellent and wear long sleeves and pants every time she goes outside—even in fry-an-egg-on-your-sidewalk temperatures. “As my Jamaican mom used to say, I’m scared of mosquitoes like the devil is afraid of holy water!”
Mosquitoes are, in fact, hellish little bugs that take the gold for summer’s biggest party poopers. But while most bites are nothing more than a nuisance, some can put your health at risk—especially for certain groups of vulnerable people. Here are three signs that a mosquito bite requires a trip to the doctor, stat.
1. The bite is really, really big.
Mosquito bites are typically no bigger than a pea, but if they start to look like an avocado pit (or anything larger) under your skin, you may have skeeter syndrome, Zachary Rubin, MD, a pediatric allergist in Chicago, tells SELF. Although this syndrome can pose serious health risks (more on this later), it rarely does: Less than 30 cases of a life-threatening allergic reaction to mosquitoes, called anaphylaxis, have been reported to date worldwide.
But skeeter syndrome (or even just a particularly nasty bite) can affect your quality of life, in which case you might want to see a healthcare professional like a primary care physician, allergist, or dermatologist. A doctor can prescribe you a stronger, more potent topical steroid cream that can offer more relief than over-the-counter products, he says. This can help minimize your reaction if you apply it right after you get a bite. You can also take an oral antihistamine (there are options that won’t make you drowsy like Zyrtec or Claritin) and apply an ice pack or ice cube for about 30 seconds on your bite to help calm your symptoms down.
2. The bite just keeps getting worse.
Reactions to mosquito bites typically appear within minutes to hours of getting bit and then fade away after about a week. But if you find that several days after a mosquito slurps your blood, swelling or discoloration (redness on lighter skin or more gray and purple tones on darker skin) is spreading beyond the affected area, yellow pus is oozing from underneath your skin, blisters are forming, or you’re coming down with a fever—go to an urgent care right away, Karen Blatman, MD, an allergist at Dartmouth Health in New Hampshire, tells SELF.
All of those signs indicate it might be getting infected or you may even have cellulitis, a deep-tissue bacterial infection that can spread to other parts of the body if left untreated. While it’s rare, bites from a bunch of different critters like ticks, bedbugs, spiders, and mosquitoes can lead to cellulitis. That’s because we all have some bacteria on our skin and under our nails, so when we scratch at an itchy bite, harmful germs can wiggle their way in, Dr. Blatman says. (So resist the urge and opt for some of that anti-itch cream we talked about instead, she says, which will also lower your chances of developing an infection.) Luckily, topical or oral antibiotics work really well if bacteria do invade the area, although some people might need longer treatments via IV if they’re sick enough.
But here’s where it gets a little complicated. Folks with skeeter syndrome will also experience the pain, discoloration, and hot skin that can look like cellulitis, so it can be really hard to tell the difference between the two, Dr. Rubin says. A good way to track how your bite changes over time is to draw a border around it with a marker; if swelling or redness spreads outside of it, see a doctor. If you still aren’t sure if your bite really is getting worse, err on the side of caution, especially if you have conditions like diabetes and lymphedema, which is a buildup of fluid in the tissues just under your skin, that increase your risks of cellulitis, Dr. Rubin says. “If there’s ever any confusion or doubt about your bite, you need to have a physician take a look at it.”
And if you or a loved one start to have difficulty walking or talking, or are just acting abnormally, go to the emergency room, Dr. Rubin says, because that could be a sign of a more severe infection.
3. You develop nausea, muscle pains, headaches, or diarrhea.
A terrible bout of itchiness isn’t the only thing mosquitoes can give you: Some of them also carry viruses or parasites that can cause certain diseases such as dengue, malaria, and West Nile virus—all of which were of “public health concern” in the US in 2023, according to the Department of Health and Human Services. About 2,000 infections of each of these diseases are reported each year, mostly in travelers to other countries although some cases are acquired in the US. Dr. Rubin says bites from disease-carrying mosquitoes don’t really look any different from normal ones, but you may develop symptoms like nausea, vomiting, headache, diarrhea, chills, fever, rash, joint pain, and muscle aches in the days and weeks after you get bit.
In a lot of cases, however, you may not feel bad at all. For example, only about 1 in 4 people with dengue will develop symptoms, and most people will recover in a week. But about 1 in 20 will develop a severe case just within hours of getting bit, which can lead to shock, internal bleeding, and death if not treated quickly enough. Likewise, 8 in 10 people infected with West Nile virus don’t ever develop any symptoms, but 1 in 150 will end up with really serious consequences like encephalitis (inflammation of the brain) that can lead to permanent problems, like blindness, or death.
I know that sounds pretty terrifying, but knowledge really is power in this case. If you’re equipped with the necessary info to have a productive conversation with a doctor, it will ensure you get the treatment you need when you need it. The best thing you can do to prevent any of these issues, though, is avoid mosquito bites altogether. “Avoid standing water, wear bug spray, cover your skin with clothes,” Dr. Rubin says. “Prevention is key.”
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Originally Appeared on SELF
