West Nile virus is on the rise: What Texans need to know
October 11, 2024
As fall settles in, so does this year’s cycle of West Nile virus, a mosquito-borne illness that, in severe cases, can cause lasting cognitive symptoms.
As of Oct. 8, 2024, there were 976 documented cases of West Nile virus in the U.S. Of these, 79 were in Texas – the country’s highest number of cases.
We don’t expect these numbers to decrease anytime soon due to the insatiable mosquito population. Humans are not mosquitoes’ first choice for a snack – they primarily feed from birds. But as birds fly away for winter, mosquitoes focus on feeding from, and possibly infecting, humans.
Anyone who is bitten by a mosquito is susceptible to West Nile virus. It has even affected some familiar names. Anthony Fauci, M.D., the longtime infectious-disease expert who became a household name during the COVID-19 pandemic, was recently hospitalized with the virus.
About 75% to 80% of West Nile virus patients show no symptoms, and 20% to 25% have West Nile fever symptoms including:
- Fever
- Headache
- Body aches
- Chills
- Vomiting
- Fatigue
- Rash
In less than 1% of people, the disease becomes neuroinvasive and causes acute effects that can linger long after they’ve recovered from the virus. These patients need specialized care to recover and prevent future complications.
Most people who contract West Nile won’t even know they are infected, and those who have symptoms typically recover without lasting issues. The key is to identify the infection early and get proper medical care while the virus runs its course.
Spotting and diagnosing West Nile virus
Up to half of people with West Nile fever develop a rash that usually appears as small, pink to red, raised or flat spots on the trunk (front and/or back) that can then spread to the arms and legs. The West Nile virus-induced rash is typically mild and resolves quickly.
However, UTSW dermatologist Richard Wang, M.D., Ph.D., and Senior Research Associate Eunice Lee, B.S., recently described a 67-year-old man who developed flulike symptoms and pink bumps that evolved into small blisters on his trunk. Blood tests and biopsies revealed that the patient’s symptoms including the rash were due to neuroinvasive West Nile virus. Because the effects of West Nile virus can often be nonspecific, the presence of a rash can aid in earlier diagnosis.
"Because the effects of West Nile often mimic those of a flu, a rash can help patients and providers realize that the virus might be a suspect and get early care if necessary."
Diagnosing neuroinvasive West Nile virus
In the rare event that West Nile affects the brain or spinal cord, there are typically three ways that the virus manifests, though these presentations can overlap:
- Meningitis: Protective layers around the brain and spinal cord, called meninges, become swollen due to infection. This leads to symptoms such as severe headache, fever, stiff neck, and sometimes confusion or sensitivity to light.
- Encephalitis: The virus enters the brain and triggers an immune response, causing inflammation, swelling, and nerve cell damage in the brain tissue that disrupts normal brain function. Symptoms include confusion, memory problems, difficulty speaking, weakness, seizures, and loss of consciousness. In severe cases, encephalitis can be life-threatening or cause long-term problems.
- Spinal cord infection: When the virus infects the motor neurons in the spine, it can cause weakness, muscle twitching, impaired movement, or paralysis. Some patients develop poliomyelitis, which causes full/partial paralysis without loss of sensation.
While many people will recover from neuroinvasive West Nile virus, some will have lifelong movement deficits. The UTSW lab of J. David Beckham, M.D., is dedicated to investigating some of the long-term effects of West Nile virus, including symptoms that mimic Parkinson’s disease. Dr. Beckham and his team are striving to understand why some West Nile survivors develop these intense motor symptoms.
Diagnosing and treating West Nile virus
The most common diagnostic test for West Nile virus is a blood test that looks for antibodies IgM and IgG, which protect against the virus. If West Nile virus is suspected, doctors may also use a test called a polymerase chain reaction (PCR) to detect the virus’s genetic material in blood, cerebrospinal fluid, or other bodily fluids.
Even though West Nile is on the rise, it’s still relatively rare – and because it acts like other viruses, it can be tough for patients and providers to spot right away. Let your provider know about any skin changes to help fast-track your diagnosis.
Because West Nile is a virus, the goal of treatment is to support the body’s natural ability to recover while it clears the virus. Providers likely won’t prescribe an antiviral or antibiotic, though they may recommend a prescription or over-the-counter treatment to help manage symptoms.
If encephalitis affects the part of the brain that controls breathing, patients may need special care. This includes support for breathing, proper nutrition, and treatment for other brain or spinal symptoms. Such care is crucial for recovery and overall well-being.
In some cases, doctors might use antibody treatments. These treatments may help the immune system fight the virus more effectively in certain cases. They use pooled donor antibodies that may include some that specifically target West Nile virus. By improving the body’s ability to recognize and attack the virus, these treatments can help reduce the severity and length of the illness.
Preventing West Nile virus
West Nile virus prevention can be as simple as preventing a mosquito bite. But as anyone who’s been outside during the Texas summer will tell you, that can be easier said than done.
Follow these tips to reduce the likelihood of mosquito bites:
- Avoid the outdoors at early morning and dusk, when mosquitoes are most active.
- Wear long sleeves and pants to help protect your skin.
- Eliminate standing water. Mosquitoes breed in standing water, so regularly empty or treat sources like birdbaths and flowerpots.
- Use a repellant with DEET. Apply DEET-based insect repellant on exposed skin and clothing to effectively keep mosquitoes away and reduce the risk of bites. DEET blocks the receptors that mosquitoes use to sense carbon dioxide and body odors, which they rely on to find their hosts. DEET is safe to use as long as you follow package instructions, including during pregnancy.
As West Nile virus cases increase in Texas, stay informed and take preventive measures. While most infections are mild or asymptomatic, some can lead to serious conditions affecting the brain and spinal cord. If you have symptoms or notice unusual rashes, seek medical care. Taking these steps can help you stay healthy and reduce the risk of serious illness.
To talk with an expert about West Nile virus, call 214-645-8300 or request an appointment online.
