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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