West Nile virus: Death toll reaches 54

ATLANTA, Georgia (CNN) -- The number of deaths linked to the West Nile virus this year continues to rise, according to the U.S. Centers for Disease Control and Prevention.

The number of people who have died nationwide as a result of the virus is now at 54, the CDC said. The largest number of deaths by state is 13 in Illinois. Eleven deaths have been reported in Louisiana and seven in Ohio.

A total of 1,295 people have been diagnosed with the virus in more than 30 states this year, and health officials say thousands more are likely infected.

Most who contract the virus experience only minor symptoms or none at all. About one in 150 develops encephalitis or meningitis.

Those cases generally involve people with weakened immune systems. In those instances the virus can prove fatal.

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The West Nile virus is carried by mosquitoes. But the CDC has determined it can also be spread through organ transplants.

Health officials believe the virus may also be transmitted through blood transfusions. The CDC is investigating whether several people nationwide were infected through transfusions.

Lawmakers on Capitol Hill are becoming increasingly concerned. The Senate Subcommittee on Public Health is scheduling a hearing with health officials to discuss what's being done to combat the spread of the virus.

Mosquito control units in many states are working to clear out large standing areas of water, such as swamps, in which infected mosquitoes may be breeding. They're also encouraging people to clear small standing areas of water near their homes.

Health officials say people should wear long pants and long sleeves when outside and use bug sprays containing deet, a chemical that health officials say keeps mosquitoes away.