The Maricopa County Department of Public Health is reminding the community to prevent mosquito bites with 36 human cases of West Nile virus infection reported this season, including one death. In 2020, Maricopa County had three West Nile virus human cases and one death, so this is a significant increase in cases. The individual who died was an older adult who also had other health conditions. While adults over 60 and those with chronic health conditions are most at risk for serious complications of West Nile virus, young healthy individuals can also get severe disease.
“We all need to do our part to protect ourselves, our family and our neighborhoods from mosquito-borne diseases,” said Dr. Rebecca Sunenshine, medical director of the Disease Control Division at Maricopa County Department of Public Health. “With so much rain this summer, we all need to stay mindful of eliminating standing water where mosquitos can breed, like pet dishes, potted plants, and even toys.”
West Nile virus is typically spread through the bite of an infected mosquito. Although it can cause severe disease, only about 1 in 5 of those infected will develop any symptoms at all. Those who do develop symptoms usually experience a flu-like illness including fever, headache, body aches and muscle weakness. Rarely, about 1 in 150 people infected can develop encephalitis or meningitis (inflammation of the brain or of the spinal cord). This more severe form of the disease can present with headache, neck stiffness, vision loss, paralysis and other neurologic symptoms. These severe cases can lead to very prolonged illness, permanent paralysis or death. Those who are over 60 years old, have underlying medical conditions or have depressed immune systems are at higher risk for the more severe form of West Nile virus.
Preventing mosquito bites is critical both at home and while traveling since many mosquito-borne diseases like dengue, chikungunya and Zika virus occur in popular travel destinations in the Americas, Caribbean, Pacific Islands and Africa. To date, Maricopa County has only seen travel-associated cases of these diseases.
“Public Health is working very closely with healthcare providers, Maricopa County Environmental Services and state and federal partners to maintain a strong surveillance system both for humans and mosquitoes, and to put prevention strategies in place,” said Dr. Sunenshine.
Maricopa County Public Health officials urge all residents and visitors to “Fight the Bite” and follow simple precautions to avoid mosquitoes and the diseases they may carry:
- Avoid mosquito bites day and night
- Use insect repellent containing DEET, Picaridin, or other EPA-registered repellants according to the product label on exposed skin and clothing
- Drain and remove containers that hold water from around your home where mosquitoes can breed, such as plastic covers, buckets, old tires, plant trays, pet bowls, toys, and boats
- Scrape the sides of the dish or inside potted plants where mosquitoes lay their eggs
- Make sure doors and windows have tight-fitting screens, no holes, and remain closed
- If it’s not too hot, wear lightweight clothing that covers your arms and legs
- Ensure that swimming pools and decorative water features are properly maintained
Maricopa County Environmental Services Department (MCESD) conducts a proactive and aggressive year-round mosquito surveillance and abatement program. This year, MCESD has seen a nearly 400% increase in positive West Nile virus mosquito samples compared to all of last year. Mosquitoes are all over the Valley, so residents across Maricopa County need to protect themselves whenever they are outside.
For more information on mosquito-borne illnesses in Maricopa County, go to FightTheBiteMaricopa.org or NoSeDejePicar.org.