West Nile expert: Not a time to panic

Dr. Scott Wetterhall: "This is something that can be prevented."

ATLANTA, Georgia (CNN) -- When it broke onto the American scene three years ago, the West Nile virus was a phenomenon confined largely to New Jersey and New York. The recent death of a 71-year-old Atlanta woman from the virus and two confirmed cases in Florida demonstrated the virus' widening impact. Dr. Scott Wetterhall, a leading member of the Metro Atlanta West Nile Task Force, talked with CNN's Martin Savidge on Saturday about the disease and what people can do to protect themselves.

SAVIDGE: One of the things that should be stressed here is that, really, as much as there is concern, there should not be panic -- the percentage of [people] really contracting this disease is very low.

WETTERHALL: We feel that there is an appropriate point of concern that people should have, but there really is no need for panic. This is something that can be prevented with appropriate personal practices in terms of wearing appropriate clothing, wearing insect repellent, not going out when the mosquitoes are biting, things like that. This is not a time for panic.

SAVIDGE: Another thing that is true is that a lot of people can be infected with this disease and yet never really feel as if they are sick.

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WETTERHALL: This is true. There have been some studies that have shown that in a given area, a very, very small percentage -- perhaps 1 percent of the mosquitoes -- are actually infected with the virus.

If a person is bitten by an infected mosquito, the chances of [getting West Nile virus] is very, very small. The proportion of people who become actually ill once they've been infected is even smaller, and it's a very, very rare event for someone to become severely ill and succumb to the illness.

SAVIDGE: And what's the course of treatment if a person does become ill?

WETTERHALL: For the most part, since most people only experience flu-like symptoms, various cold remedies and symptomatic care is all that is needed. For somebody who develops a severe, debilitating disease, such as encephalitis, which is a swelling and infection of the brain … that usually requires more supportive measures within a hospital. Measures to support breathing functions, kidney functions, heart functions and things like that.

SAVIDGE: Who is most susceptible to becoming very ill?

WETTERHALL: Basically, those at risk are the elderly -- those persons who are older than 50 years of age -- and those with weakened immune systems.

SAVIDGE: And is this a problem that is going to go away with, say, the first frost?

WETTERHALL: Since the disease is transmitted by mosquitoes and since hard frosts tend to kill the adult mosquito population, we would expect that there would be no longer transmission of the disease following a hard frost.

SAVIDGE: But does the threat come back the following summer, or when the weather warms up once in awhile?

WETTERHALL: The experience that we've had elsewhere in the United States is that once it's been introduced into an area, it's in all likelihood going to stay with us.