I know that mosquito bites are annoying, and we hear about West Nile Virus, and I see the signs all over that West Nile can come from mosquito bites, but do we really know what that means? What are the symptoms of West Nile? Is it a big deal? Do I even care? I have been getting a lot of questions about this especially since there have been numerous reports of West Nile Virus found in certain areas around where I live, and the Center for Disease and Prevention (CDC) has reported that 48 of the 50 states have fond cases this summer. So, let’s get to the bottom of it!
What is West Nile Virus?
West Nile virus is a virus transmitted by mosquitos that can cause very generalized reactions, ranging from very mild to very extreme, with potential for very serious illness. It is considered a seasonal epidemic that flares up in the summer in North America and remains as a high threat through the fall. The CDC reports that this summer has the highest rates of West Nile (just shy of 1600 cases) since it was first found in 1999, and 70% of the cases are from Louisiana, Oklahoma, Texas, South Dakota, Mississippi, and Michigan.
What are the symptoms?
The virus is really defined by the symptoms really. Only about 1% of people who are infected will get a serious reaction and the two most determining factors seem to be age over 50 years old, and having a weakened immune system (due to transplantation, immunosuppression, chronic disease, etc.) It takes anywhere from 3-14 days to have symptoms of the virus after being bitten. Most people have absolutely no symptoms at all, while other people might have mild symptoms that include:
-swollen lymph nodes
More severe symptoms include:
-severe headache (like a migraine)
-stiff neck muscles
-muscle weakness and/or lack of muscle coordination
*These symptoms usually last a few days but the symptoms that are more severe last a week or more and some, like paralysis, can be permanent. If you have these symptoms, you should seek medical care.
How is it transmitted?
WNV is primarily transmitted to humans and animals through mosquito bites, and the mosquitos become carriers after feeding on dead birds that are infected with the virus. Other ways of transmission are through blood transfusion and organ transplantation, but it is now a virus that is screened for more thoroughly, so the risk is significantly diminished. But, you are at your highest risk to become infected during warm weather, due to the nature of the transmission and high breeding levels of mosquitos!
How can I be diagnosed?
Your HCP will determine based on your symptoms if you need further testing, but they will start with lab tests to look for an increased level of antibodies to the WNV, which means that your body is fighting off the virus or has recently. If you have increased antibodies, you will then most likely get a lumbar puncture (AKA a spinal tap) to assess for the virus in your cerebral spinal fluids (CSF); to help diagnose the meningitis (stiff neck, high fevers, muscle convulsions/rigidity). The CSF that is drawn off, if infected will show high levels of white blood cells (WBCs) and also the WNV antibodies. And finally, if you are having confusion/stupor, etc. you will be ordered for an MRI or an electroencephalography (EEG) to study your brain and the swelling (MRI), and the brain waves and function (EEG) to determined the severity of the infection.
Are there treatments?
Because it is a virus, not really, no. Most of the “treatment” is just rest, and supportive care like Intravenous (IV) fluids if you are in the hospital, using tylenol/advil to treat fevers, eating a healthy diet, and focusing on regaining strength. There is some current research looking at interferon therapy, which is a immune modulating therapy, to help people with severe symptoms overcome the virus faster but the research is in pretty early stages, although at this point it looks promising, interferon therapy is a very intense therapy.
How can I protect myself?
From your home/living area, try to reduce breeding of mosquitos by eliminating any standing water, like change out bird bath date frequently, anything that has still sitting water in it, dump it, and clean out gutters. Anything moist, damp, or filled with water is the perfect little breeding ground for mosquitos, so do what you can to eliminate them! Also, make sure to change out your animals water bowls that are left outside (if you have one). And how to prevent getting bitten? Wear long sleeves and long pants if going into mosquito ridden areas, especially at dusk or dawn as that is when they are most likely to swarm. Also use insect repellent with DEET (avoiding faces and hands of children) and for young infants you can cover their strollers with mosquito netting (do not use DEET on children under 2 months). Use good sense, and use the monthly medications to prevent your dogs/cats from getting infected too!
If you are worried about your risk because you spend a lot of time outdoors, in the woods, or in high risk areas, then talk to your HCP about your risk and other ways to prevent WNV. Also, talk to your HCP about any symptoms you may have had, they may want you to come in for further testing, or come in earlier if you experience symptoms again, to be able to diagnose you! Wear that bug spray!!
Yours in Good Health