There is no reason for panic over this week's death of an 84-year-old Acre woman from complications of West Nile virus, the Health Ministry said Wednesday. It was the first death of the season from the virus, against which there is no vaccination. There have been 16 suspected cases of infection this season, four of them confirmed. The Jewish woman, who suffered from several chronic disorders, died at Western Galilee Hospital in Nahariya. She was not accustomed to leave her house, meaning she was bitten by an infected mosquito at home, according to ministry epidemiologists. Tel Aviv district health officer Prof. Tami Shohat, who Wednesday was filling in for the head of the ministry's public health services department, said it was a typical case in which the victim was at home and did not, according to her relatives, notice that she had been bitten by a mosquito. Mosquitoes breed in standing water (even a pail) and are infected by migrating birds. The West Nile virus causes a mild flu-like condition in most people who are bitten by infected mosquitoes. But people with weakened immune systems such as the elderly and those with cancer or chronic diseases may be susceptible to developing complications such as encephalitis or meningitis, said Dr. Shahib Shahib, the public health officer in Acre. The virus caused a public health scare in 2000, when 500 people were infected and 34 of them died. Shohat and Shahib said the disease rises and ebbs, and the number of infections and deaths was not steady. Some years there is more insecticide spraying by the Environmental Protection Ministry, but it is impossible to wipe out the mosquitoes. They usually die out by November as the weather turns colder and the rains come. People with weak immune systems should protect themselves with window screens, mosquito repellants and wear long-sleeved light clothing to avoid bites, Shahib said. The Environmental Protection Ministry said it found infected mosquitoes in three parts of the country over the last two weeks: Nahal Adashim north of Afula, Shahar near Kiryat Gat and Ma'ayan Zvi near Zichron Ya'acov. When the ministry detects such insects, it sends out teams to spray.