The number of people who have been diagnosed with West Nile virus this year is higher than it was at this time in the record-setting 2002 season. Experts from the Centers for Disease Control and Prevention, the Food and Drug Administration and the Department of Agriculture answered questions from reporter Anita Manning about this year's epidemic. Q: How many cases have been reported this year?
A: The number of cases reported to the CDC, as of Monday, was 536, including 11 deaths. Last year on this date, states had reported 251 cases and 11 deaths. By the end of the year, there had been a total of 4,156 cases and 284 deaths. This year's higher numbers suggest milder cases are being reported to the CDC, officials say, as doctors have become more aware of the disease. The majority of cases this year have been in Colorado, where the CDC reports 257 cases, including six deaths.
Q: What are the symptoms?
A: Most people get what doctors call West Nile fever, which includes fever, headache and body aches, sometimes with a skin rash and swollen lymph glands. In many mild cases, people who are infected may not even know it. But the virus can cause encephalitis (inflammation of the brain) or meningitis (inflammation of the lining of the brain and spinal cord). These conditions can be life-threatening or cause long-term damage.
Q: How do you catch it?
A: The virus usually passes back and forth between birds and the mosquitoes that bite them, but infected mosquitoes can pass the virus to humans or animals. It also can be transmitted in blood and through breast milk. The CDC says nursing mothers who feel ill should contact their doctors, but there is no reason for healthy mothers in West Nile-affected areas to stop breast-feeding.
Q: What about pregnant women?
A: One case has been reported of a mother passing the virus to her unborn child; the child was born with serious medical problems. The CDC advises pregnant women to reduce their exposure to mosquitoes and wear DEET-based repellant when outside.
Q: What is being done to protect the blood supply?
A: After 23 people were infected with West Nile from blood transfusions last year, blood banks, pharmaceutical companies and the FDA rushed to develop tests for the virus. They are now being used to screen all donated blood in the USA and Canada.
Q: Who is at greatest risk of serious illness from West Nile virus?
A: People over age 50 are more likely to get seriously ill, but the virus has caused illness in people of all ages.
Q: What about a vaccine?
A: Companies working to develop a vaccine are reporting progress, but it takes time to assure safety and effectiveness. There is a vaccine that is effective in horses, though, and the USDA urges horse owners to use it.
Q: How vulnerable are horses to West Nile virus?
A: The USDA says 14,717 horses were sickened last year, and it's estimated that at least a third of them died or were euthanized. This year the number of cases reported in horses is on the same pace as last year.
Q: What about other animals?
A: West Nile infection has been detected in hundreds of bird species and other animals including squirrels, cats, dogs and domestic rabbits. Insect repellants designed for humans shouldn't be used on pets, mainly because the animals can ingest them when they lick their fur. Veterinarians can recommend safe products for pets.
Q: How can I protect my family?
A: Avoid mosquito bites by staying indoors during the early morning and early evening hours, when mosquitoes are most active. Wear long, loose clothing and spray clothing and exposed skin with an insecticide that contains DEET at a maximum concentration of 35%. Children should use insecticide with 10% DEET concentration. Mosquitoes breed in or near water, so get rid of breeding sites around your property. Empty containers that could collect water, clean gutters, drain ditches and repair holes in screens.
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