A fourth case of West Nile virus has been reported in Suffolk County, a senior official said

A fourth person has been diagnosed with West Nile virus in Suffolk and the patient, who lives in the city of Islip, has been released after a short hospitalization, the county health department said Tuesday.

The patient, who became ill on Sept. 1, was under 55, said Dr. James Tomarken, Suffolk County Health Services Commissioner, in a statement.

Those most exposed to the potentially fatal virus, carried by infected mosquitoes, are over 55 years of age or have chronic health problems or weakened immune systems.

Health officials in Suffolk said last week that there were two more cases of West Nile virus, one in Huntington City and the other in Smithtown town. These two individuals, both over the age of 55, have recovered, said Tomarken.

On September 12, the county declared that a patient who lives in Babylon and is over 55 years old was hospitalized on August 19th. This individual was not released, he added.

About 20% of people infected with West Nile virus develop symptoms, said Tomarken.

Mild symptoms may include fever, headache and body aches, rash, and swollen lymph nodes.

Symptoms in more severe cases may include high fever, stiff neck, stupor, disorientation, coma, tremors, seizures, muscle weakness, vision loss, numbness, and paralysis.

Supportive care can help those affected, said Tomarken, who urged people who experience these symptoms to seek medical treatment. There is no specific treatment for the virus.

Tomarken urged residents to eliminate stagnant water where mosquitoes could breed. If they are part of the risk groups, he said that they should take extra precautions, such as the use of insect repellent, from June 1 to November 1.