Mosquito and tick-borne illnesses increasing What you should know

Mosquito and tick-borne illnesses increasing What you should know

Rise in Tick and Mosquito Illnesses Calls for Precautions

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Published on July 17, 2023

Illnesses transmitted by ticks and mosquitoes are on the rise, prompting warnings from doctors and scientists to take precautions and watch out for any telltale symptoms. In recent months, cases of malaria from mosquitoes and tick-borne diseases have seen alarming increases in the United States. These trends emphasize the need for heightened awareness and preventive measures to combat the growing threat of vector-borne diseases.

The Alarming Rise of Vector-Borne Illnesses

At least seven cases of locally transmitted malaria were reported last month in Florida and Texas. This marks the first local spread of malaria in the United States in 20 years. Additionally, cases of tick-borne illnesses, such as Lyme disease, have risen by 25% between 2011 and 2019, totaling 50,856 reported cases in the latter year, according to the CDC. In some Northeastern states, cases of babesiosis, another tick-borne disease, have more than doubled during the same time frame.

Arizona also experienced the largest outbreak of West Nile virus spread by mosquitoes in 2021 since its detection in the U.S. in 1999.

The Role of Climate Change and Global Travel

While malaria was eradicated in the U.S. by the 1950s, owing to the widespread use of insecticides, screened windows, and air-conditioning, newer vector-borne diseases continue to emerge. A 2020 CDC report reveals the presence of 17 different vector-borne illnesses in the U.S. since 2004, with nine new pathogens identified during this period.

“We are seeing more reported cases of vector-borne diseases as the climate gets warmer and people travel more,” says Debopam Chakrabarti, PhD, professor and head of the Molecular Microbiology Division at the University of Central Florida. He notes that individuals visiting endemic areas, such as Haiti, the Dominican Republic, southern Mexico, and Central America, are more susceptible to mosquito bites and contracting diseases like malaria.

Recognizing Symptoms and Risks

Malaria, spread by anopheles mosquitoes, can be life-threatening. Symptoms usually appear 10 to 15 days after an infected mosquito bite and include high fever, chills, nausea or vomiting, headache, diarrhea, and fatigue. While there are about 2,000 cases of malaria reported annually in the U.S., the recent clusters of cases are considered rare incidents. “Occasionally, we have ‘airport malaria,’ when a plane lands with infected mosquitoes, which then escape,” warns Bob Bollinger, MD, MPH, professor in infectious diseases at Johns Hopkins University School of Medicine. He explains that the mosquitoes that transmit malaria can fly up to a couple of miles.

Regarding tick-borne diseases, Sarah Gunter, PhD, assistant professor of pediatric tropical medicine at Baylor College of Medicine in Texas, emphasizes that Lyme disease is more common, with several new types emerging in the last 40 years. Symptoms of Lyme disease, transmitted by deer ticks, often begin with a bull’s-eye rash and, if left untreated, can lead to fever, rash, facial paralysis, and arthritis. Recent data from the health care technology company Athenahealth reveals that in the first week of June, case numbers were 17% higher compared to the previous year. Symptoms often include nonspecific flu-like symptoms such as fever, chills, sweats, headache, body aches, loss of appetite, nausea, or fatigue. Babesiosis, another tick-borne disease, often presents flu-like symptoms as well.

Rocky Mountain spotted fever, considered one of the deadliest tick-borne diseases, can cause confusion, headache, muscle pain, and a characteristic rash on the wrists and ankles. While tick-borne diseases are more common in the Midwest and Northeast, most cases of Rocky Mountain spotted fever have been reported in the eastern U.S., specifically in states such as North and South Carolina, Virginia, Georgia, Tennessee, and Oklahoma.

“It’s important to identify and treat these diseases early,” urges Gunter.

Exploring New Approaches for Prevention and Treatment

As the number of cases continues to rise, researchers are actively working to develop innovative ways to prevent and treat vector-borne illnesses. Biotech companies such as Pfizer and Valneva have reached the late-stage clinical trials for their respective Lyme vaccine candidates, with completion expected as early as 2025.

Debopam Chakrabarti and his team at the University of Central Florida, in collaboration with researchers from Stanford University and the University of California-San Diego, are investigating the use of cancer drugs for treating malaria. Their research, funded by a 5-year grant from the National Institutes of Health, explores the potential of protein kinase inhibitors, originally developed for cancer treatment, as an accelerated path to drug therapy for malaria.

“Cancer compounds have already gone through clinical trials, which saves both cost and time,” says Chakrabarti, highlighting the promising prospects of their approach.

Protecting Yourself: Preventive Measures

To minimize the risk of infection, experts recommend taking preventive measures, including wearing insect repellent and long sleeves, ensuring screens on windows, and removing any standing water around the house that may attract ticks and mosquitoes. When walking in areas with a high tick population, it is essential to wear clothing that covers the arms and legs and conduct thorough tick checks afterward. Mosquitoes are more active during the evening and early morning hours, so extra caution is advised during these times.

The CDC suggests treating clothes and outdoor gear with products containing 0.5% permethrin, an ingredient effective in killing and repelling ticks and mosquitoes that remains active even through multiple washings. Tick checks should focus on key areas such as the underarms, hair and ears, and the waist and backs of knees.

With awareness, preventive measures, and ongoing research, we can take significant steps in reducing the risks associated with vector-borne illnesses. Stay vigilant, stay protected!


  1. WebMD
  2. Centers for Disease Control and Prevention (CDC)