| Treasure Coast Newspapers
West Nile Virus Leading Symptoms Explained
West Nile virus is the leading cause of mosquito-borne disease in the US, with the highest concentration in the Midwest. Find out if you are infected here.
The Martin County Health Department announced a human case of the West Nile virus Monday – the first on Treasure Coast.
West Nile virus has been seen frequently in sentinel chickens in Martin, St. Lucie, and Indian River counties.
Human cases have been observed across Florida every year since the first report in 2001. This is according to data from the Florida Department of Health, with major outbreaks in 2003 and 2012 in 94 and 74 cases, respectively.
The disease debuted in the United States in 1999 in Queens, New York. Since then, 52,284 human cases have been reported to the Centers for Disease Control and Prevention on November 24, with a death rate of 4.7%.
What made the Treasure Coast see its first human fall, and should residents expect to see more?
West Nile Virus on Treasure Coast
In Martin, St. Lucie, and Indian River counties, all sentinel chickens tested positive for the West Nile virus this year.
The more sentinel chickens – which are used to assess the presence of mosquito-borne diseases – that test positive, the greater the likelihood of infection in humans, said Geoffrey Duesterbeck, Martin County’s mosquito control manager.
The Treasure Coast, and Martin County in particular, saw unprecedented rainfall this year, resulting in numerous waves and standing water, making the perfect breeding ground for mosquitoes, Duesterbeck said.
More: Parts of Martin County receive 20 inches of rain in 5 days
More: The Hobe Heights neighborhood bore the brunt of the Martin County’s flooding
Rain alone might not have been the only factor that helped Treasure Coast saw its first human case of the West Nile virus, Duesterbeck said, since mosquito-borne disease outbreaks are sporadic and can occur at any time.
“There is no real way to point a finger and say that is why we had a human case,” he said.
The cool, dry weather that ushered in December 1st promised that mosquito activity will decrease.
It doesn’t completely rule out the possibility that a Treasure Coast resident might contract a mosquito-borne disease, Duesterbeck said, but it’s less likely.
Data shows Martin County’s highest mosquito activity was in August, Duesterbeck said.
Mosquito Control has already seen a significant decrease in service requests, he added, but the department is still taking preventative measures like larvaciding – or spraying chemicals near standing water to reduce mosquito populations in adults – and misting up adults Mosquitoes with adulticides.
Indian River County has had no mosquito-borne diseases in the past three weeks, said Mark Kartzinel, the county’s mosquito-control medical entomologist. The main activity was in mid to late October.
St. Lucie County has also seen a decline in activity and is confident that cooler weather will continue to slow its population, said the county’s mosquito control director Roger Jacobson.
All three counties are still taking preventive measures and are still under mosquito-borne disease counseling.
Mosquito-borne disease outbreaks
This may be the first human case of West Nile Virus on Treasure Coast, but it isn’t the first mosquito-borne disease outbreak.
St. Louis encephalitis found its way through Florida in late 1990 with a total of 223 positive cases and 11 deaths across the state.
Indian River County was believed to be the epicenter of the outbreak when a Fellsmere man became the first suspected human case in July 1990. The county eventually saw 19 cases and one fatality, an 81-year-old Vero Beach woman, and had the highest case-to-population ratio that year, according to the Treasure Coast Newspapers Archives.
Night-time activities such as Halloween, Christmas tree lights, and school sports have been suspended to help slow the spread of St. Louis encephalitis.
Martin County had an outbreak of dengue fever in August and September 2013, according to a Florida Department of Health report. 28 residents were infected mainly in Rio and downtown Jensen Beach.
Calling it a dangerous rarity at the time, having seen just one case before the outbreak in 2011, local health officials called it door-to-door to educate residents about the disease. One opinion lasted for four months.
No deaths were reported and six residents were hospitalized with symptoms.
There was also a small outbreak of Chikungunya fever in 2014. Data shows there were six cases in St. Lucie and two in Indian River Counties.
Most mild cases of mosquito-borne diseases show the same symptoms and are flu-like – fever, headache, body ache, nausea, or rash. Laboratory and blood tests are often needed to confirm a diagnosis and differentiate between diseases.
West Nile Virus Symptoms and Severity
There are no vaccines for the West Nile virus or drugs to treat humans, but most infected people don’t feel sick – only about 20% have symptoms, according to the CDC.
The most common symptom is a fever. However, more severe cases can include headache, body aches, joint pain, vomiting, diarrhea, rash, or effects on the central nervous system leading to encephalitis or meningitis. Recovery can take several weeks or months.
About 10% of patients who develop serious central nervous system disease die from West Nile virus.
As of November 24, there were 46 human cases in Florida reported to the CDC – 36 were neuroinvasive or able to infect the nervous system, and the other 10 were non-neuroinvasive. It is believed that another 40 people have the disease but were asymptomatic. Three led to death.
Residents should take preventive measures, including:
- Cover the skin with clothing or repellent
- Drain off standing water to prevent mosquitoes from multiplying
- Cover doors and windows with screens to keep mosquitos out of your home
Catie Wegman is a community reporter who also produces “Ask Catie,” an occasional role in finding answers to your burning questions about anything and everything – the more bizarre the better. Contact her at firstname.lastname@example.org and follow her on Twitter at @Catie_Wegman and on Facebook at @ catiewegman1.