West Nile, bird flu cases in Texas

Public health officials urge Texans to be vigilant in protecting against mosquito bites after confirming the first Texas case of West Nile virus and 10 travel-associated dengue cases for 2024. Precautions should be taken in Texas and while traveling internationally to countries where dengue is endemic.

The first case of West Nile in 2024 was reported in a Montgomery County resident who has been diagnosed with West Nile fever. As of today, the Texas Department of State Health Services has identified nearly 800 mosquito samples infected with West Nile virus in 24 counties.

West Nile virus is transmitted through the bite of infected mosquitoes. Most people exposed to the virus don’t get sick, but about 20 percent develop symptoms like headache, fever, muscle and joint aches, nausea and fatigue. In a very small proportion, less than one percent, the virus affects the nervous system, leading to the more serious West Nile neuroinvasive disease that can cause neck stiffness, disorientation, tremors, convulsions, paralysis and even death.

There were 154 cases of West Nile disease in Texas last year and 13 deaths.* Over the last five years, Texas has had 497 cases and 68 deaths. There were 79 cases of dengue in Texas last year, including one locally acquired case in Val Verde County. A person in Texas became ill with bird flu after contact with infected dairy cattle, state officials reported Monday, July 29.

It’s the first human case of the highly pathogenic strain of avian influenza in Texas, and it’s the second recorded in the U.S., according to the health alert state officials issued.

“The risk to the general public is believed to be low; however, people with close contact with affected animals suspected of having avian influenza A(H5N1) have a higher risk of infection,” the alert said.

The patient’s primary symptom was conjunctivitis, or eye redness, according to the alert.

State officials recommend that clinicians should “consider the possibility” of infection in people who have symptoms and a potential risk for exposure, including those who have had close contact with someone infected, contact with affected animals, or contact with unpasteurized milk from dairy farms with infections.

Symptoms can include a fever, cough, sore throat, runny or stuffy nose, headaches, fatigue, eye redness, shortness of breath, diarrhea, nausea, vomiting, or seizures. The illness can range from mild to severe, and health care providers who come across someone who may have the virus should “immediately consult their local health department,” according to the alert.

Because eye redness has been observed in these infections before, health care providers like optometrists and ophthalmologists “should be aware of the potential of individuals presenting with conjunctivitis who have had exposure to affected animals,” according to the alert.

The strain, novel avian influenza A(H5N1), started infecting dairy cattle in the Panhandle last week, in another blow to the Texas cattle industry after thousands were lost in historic Texas wildfires. Similar outbreaks were reported at dairies in Kansas and New Mexico.

The U.S. Department of Agriculture said there is no safety concern to the commercial milk supply. Consumer health is also not at risk, the department said. The milk from impacted animals is being dumped or destroyed and will not enter the food supply.