What’s Eating You? A Guide to West Nile

Hello! My name is Josie and I am the new nurse practitioner at Relieve Allergy, Asthma & Hives. I just moved from Ohio which means I’m trading centipedes and brown recluse spiders for scorpions and rattlesnakes. While learning about all the dangerous Arizona critters, I was shocked to learn about one of my native insects but with a scary twist: mosquitos with West Nile virus. Please keep reading to protect you and your family from mosquitoes this Halloweekend!

Maricopa county has had a significant increase in the amount of West Nile Virus (WNV) transmission from recent years. Researchers were already concerned with a total of 174 WNV cases in 2019 (the most since 2004), but somehow counts are already at 699 WNV cases with 47 deaths as of mid-October 2021. There are typically two spikes per year; the first spike is in August and then the second in late September, however, the spikes seem to be starting earlier and lasting longer due to the heavy monsoons.

The WNV transmission cycle begins when a mosquito feeds on an infected bird and then spreads WNV to people or other animals by biting them and injecting their saliva. Unfortunately, there is no vaccine (for humans at least, horses do have a WNV vaccine) or medication to prevent transmission and about 1 in 5 bitten by an infected mosquito will develop symptoms. Further, about 1 in 150 will develop a serious illness that could result in death. You may be at a higher risk of serious illness if you are older than 50 or are immunocompromised, signs of which include recurrent and persistent ear infections, sinus infections, pneumonia, and thrush and the frequent need for antibiotics to clear infections. You should schedule an appointment with Dr. Wendt if you are worried about immunodeficiency.

We have included a guide below so that you can prevent infection and monitor for symptoms of WNV this fall. It is important to catch symptoms early as they may be precursors to encephalitis, an inflammation of the brain. Symptoms may develop 2-6 days after getting bit and the virus is detected by obtaining a blood test ordered by Dr. Wendt or me. There is no specific treatment for WNV other than supportive measures. This includes over the counter pain medications, IV fluids, nursing care, etc. While this can be scary to learn about, there is some good news! WNV is not spread through coughing, sneezing, touching live animals, handling live or infected birds, or through eating infected animals. Officials in Arizona are also trying to do their part by fogging areas known to have WNV infected mosquitos. The clinical signs of WNV for your pets have not been clearly defined so if you have any concerns, you should reach out to your veterinarian.

What if I have problems with mosquito bites and it’s not West Nile Virus? Then we are here to help! A mosquito injects saliva when feeding on your blood and this saliva can cause major problems if you are allergic to it. Any mosquito bites larger than a quarter and associated with symptoms such as hives, shortness of breath, anaphylaxis, large areas of swelling, low grade fever, swollen lymph nodes, bruises, and lesions around the site could suggest that your immune system provides an inappropriate response to the bite. Schedule an appointment for allergy testing so that we can help give you the relief and protection you need: (480)500-1902.

How to prevent mosquito bites (especially during Trick Or Treat-ing!):

• Wear clothing that covers legs and arms when outside
• Avoid outdoor activity during dawn and dusk
• Use EPA-registered mosquito spray
• EPA mosquito spray is safe if you are pregnant or breastfeeding
• You can use the following search engine to input length of protection time, companies, and active ingredients to find the right spray for you: https://www.epa.gov/insect-repellents/find-repellent-right-you

General Mosquito Bite Treatment:

• Wash with soap and water
• Apply an ice pack
• Mix 1 tablespoon of baking soda and enough water to create a paste; apply for 10 minutes and then wash off
• Can add an antihistamine cream if itching does not resolve
• Go straight to the emergency room with any difficulty breathing or swelling of the tongue or throat

Signs and Symptoms of WNV:

• High fever
• Swollen lymph nodes
• Headache
• Neck Stiffness
• Disorientation
• Tremors (hands shaking)
• Numbness
• Paralysis
• Muscle Weakness + Joint Pain
• Nausea + Vomiting

What can I do to help prevent the spread in my town?

• Report dead bird sightings to local authorities so they can test for WNV in the area (Environmental Services Department for Maricopa: 602-506-6616
• Once per week remove any standing water around your home since this is where mosquitos will lay their eggs
• Treat large bodies of water that are not used for drinking with larvicides
• Use outdoor adulticide in dark, humid areas like under patio furniture or in your garage

Is mosquito fogging safe for me? What if I have asthma? 

• Yes! When sprayed correctly they are not a risk to human health
• They do not cause asthma attacks
• You do not need to go inside when sprays are happening
• You can keep an eye on which areas have been fogged recently by clicking on this link: https://maricopa.maps.arcgis.com/apps/webappviewer/index.html?id=c00b3ecbb3344ca2930a30b978184ddd

Medical Advice Disclaimer: This website does not provide medical advice. This information, including but not limited to, text, graphics, images, and other material contained on this website are for informational and educational purposes only. Although we strive to provide accurate information, no material on this site is intended to be a substitute for professional medical advice, diagnosis, or treatment nor does it establish any kind of patient-client relationship by your use of this website. Always seek the advice of your physician or other qualified healthcare provider with any questions you may have regarding a medical condition or treatment and before undertaking a new health care regimen, and never disregard professional medical advice or delay in seeking it because of something you read on this website.

Sources

Center for Disease Control and Prevention. (2021, July 7). West Nile Virus. CDC.

https://www.cdc.gov/westnile/index.html

Center for Disease Control and Prevention. (2020, March 6). Mosquitoes. CDC.

https://www.cdc.gov/mosquitoes/mosquito-bites/symptoms.html

Brower, M. (2021, October 22). Heavy summer monsoon leads to worst year of West Nile Virus

in Arizona. AZ Central. https://www.azcentral.com/story/news/local/arizona-health/2021/10/22/heavy-summer-monsoons-lead-worst-year-west-nile-virus/6141101001/Maricopa County Office of Epidemiology and Data Services. (2017, June). West Nile Virus.

Maricopa County. https://www.maricopa.gov/1746/West-Nile-Virus