Inquiring Minds: Steven Opal on West Nile Virus

The West Nile Virus continues to make headlines across the United States and Canada. George Street Journal writer Scott J. Turner discussed the illness with Professor of Medicine Steven Opal, M.D., (left) chief of infectious disease at Memorial Hospital of Rhode Island.

What is West Nile Virus?

It is a type of virus transmitted by mosquitoes. It is prevalent among birds. Nothing happens to most people infected by the virus.

Usually, infections are slight. But the older you are, the more likely you are to become ill. Some people, particularly those who are older, can get encephalitis, which is inflammation of the brain and surrounding structures. Encephalitis can be fatal.

There is blood-work evidence that the virus may have infected some people in Rhode Island, but there are no cases in Rhode Island of significant encephalitis from it.

Why is there so much concern over the virus?

The virus was introduced in North America in the past decade. So an entirely new population of people is susceptible. In Egypt, for example, where the infection is endemic, it is very common to get West Nile Virus at a young age. People don’t show symptoms of illness and do fine. But in the United States, there are lots of people without antibodies for West Nile Virus because the virus has not been around here. Some of the people exposed to it here are getting infected and dying of something thought to be benign in Egypt.

What are the symptoms of infection?

Particularly prominent are muscle aches and pains. Also common are headache and fever. In one in four cases there is a nondescript skin rash. Some symptoms of severe infection are confusion, stiffness, high fever and convulsions

What treatments are available?

There is no antiviral treatment or vaccine for West Nile Virus. In lab studies, there is preliminary evidence that some antiviral agents are effective, but none has been tested in humans.

What should people do if they suspect they are infected?

Seek care immediately. Hospitalization will provide a range of supportive treatments such as the administration of fluids to fight dehydration.

The vast majority of people who get the virus show no symptoms or symptoms so mild that they don’t realize they were infected. But their bodies do produce antibodies to the infection and that will protect them. You can also get encephalitis and survive. People who recover usually do fine. But not everyone survives encephalitis.

How do you protect yourself from the virus?

Protect yourself from mosquitoes. Mosquito repellent works to some degree. If mosquitoes are present apply repellent at dawn and dusk when the insects are most active. Wear long sleeves, long pants and a hat. And limit mosquito breeding grounds by eliminating unnecessary standing pools of fresh water such as in house gutters, potted plants or neglected birdbaths.

Are health officials on the lookout for the illness?

There is considerable effort to find it. There are state mosquito surveys and dead bird samplings. The State of Rhode Island has produced a good blood test for practicing clinicians, who were notified by the state to look out for the illness and to send in blood samples if they suspected West Nile Virus.

What if you find a dead bird?

Contact animal control and ask that the bird be checked for evidence of infection.