What Bit Me? How to Identify Common Bug Bites

A mosquito bite appears as an itchy, round red or pink skin bump. It’s usually a harmless bug bite but can sometimes cause a serious illness, such as the Zika virus (particularly harmful in pregnant women), West Nile virus, malaria, or eastern equine encephalitis (EEE). For most people, Zika causes a brief, flulike illness. But newborns of pregnant women infected with Zika have an alarming rate of microcephaly birth defects. Check out the Zika Travel Information page on the website for the Centers of Disease Control and Prevention (CDC) to find out more about travel warnings and advisories.

For 2022, a total of 1,126 cases of the West Nile virus were reported across 42 states in the United States, according to the CDC. Symptoms appear 2 to 14 days after the bite and can include headaches, body aches, fever, vomiting, diarrhea, and a skin rash. People with a more severe West Nile infection may develop meningitis or encephalitis and have symptoms including neck stiffness, severe headache, disorientation, high fever, and convulsions.

The bite of a parasite-infected mosquito can cause malaria, a rare occurrence in the United States, with only about 2,000 cases diagnosed in the country each year, according to CDC data (and the majority of those are in people who recently traveled to parts of the world where malaria transmission is more common). Symptoms are similar to the flu and can include fever, headache, muscle aches, nausea, and vomiting from 10 days to 4 weeks after the bite. Malaria is serious, but it’s good to know it is preventable and treatable, according to the CDC.

Cases of EEE are rare but deadly. For people infected with EEE, 30 percent do not survive, and many who do develop neurological problems. While there was only one case reported in the United States in 2022, there were 38 cases in 2019, including 15 individuals who died from the condition, according to the CDC. Most of the cases have been reported in the Northeast.

Another emerging concern is a species of mosquito found in Florida, called Aedes scapularis. Previously found mostly in the Caribbean and Latin America, research indicates the mosquito is now well established in Florida. The invasive species has been found in Broward and Miami-Dade counties, according to one report. It’s unclear if the Aedes scapularis mosquitos in Florida are spreading any types of disease, but elsewhere, they have been shown to spread some viruses, including the Venezuelan equine encephalitis virus (VEEV) and the one that causes yellow fever.