The public became aware of the West Nile virus after 12 members of the Larrazabal clan in Ormoc City, were earlier reported to have fallen ill due to the rare virus.
One of the victims, Marcos Larrazabal II, is still in a coma and confined in the intensive care unit of the family-owned Cebu Doctors Hospital here.
Health Secretary Manuel Dayrit doubted whether the West Nile virus could be the culprit, saying it could probably be the Japanese B encephalitis virus which exhibits the same symptoms such as sore eyes, high fever and tonsillitis.
Regional health officials themselves said there has been no known case of West Nile infection in the region, or even in the whole Philippines.
"We should not label the virus as West Nile. We do not have any data yet to support such claim. The affliction could be caused by toxins, for all we know," Region 7 epidemiologist Juanito Zuasula said.
But information from the University of Florida obtained through the Internet reveals that the West Nile virus could be present in the Philippines.
The virus was first isolated in 1937 from the peripheral blood of a woman in the West Nile country of Uganda in Central Africa.
Tests for antibody to West Nile virus also suggested it is also present in Thailand, Malaysia, Turkey, Albania and the Philippines, according to the University of Florida.
Ormoc doctors, who treated the Larrazabal clan members, earlier said another kind of virus, not the West Nile, could be responsible for the illness.
According to Ormoc City Mayor Carmelo Locsin, doctors there earlier said it could have been the Japanese B encephalitis virus.
"They have already dismissed the idea that the virus could be West Nile. Most probably because of the symptoms, its Japanese encephalitis," Locsin said in an interview with radio station dyLA.
The flavivirus is closely related to the Japanese B encephalitis virus in eastern Asia, the Kunjin virus in Australia and Southeast Asia, and the St. Louis encephalitis virus in North and South America.
Locsin said the family of Marcos II has sent blood samples to the US for testing.
Dayrit said the DOH itself has sent samples to Japan and Australia and that hopefully, the test results will be out in a weeks time.
Dayrit said Dr. Consorcia Lim-Quizon, his executive assistant and officer-in-charge of the National Epidemiology Center, will also personally bring a sample to the CDC in Atlanta, Georgia.
He admitted though that they may encounter difficulty in bringing such a sample to the US because of strict regulations on the entry of biological specimens following the Sept. 11 terror attacks.
According to the CDC, people become infected by the bite of mosquitoes carrying the West Nile virus.
Mosquitoes get the virus when they feed on infected birds, which may circulate the virus in their blood for a few days. Infected mosquitoes can then transmit the virus to humans and animals while biting to take blood.
The virus is located in the mosquitos salivary glands. During blood feeding, it may be injected into an animal or human, where it may multiply and cause illness.
Following transmission by an infected mosquito, the West Nile virus multiplies in the persons blood system and crosses the blood-brain barrier to reach the brain.
The virus interferes with the normal central nervous system and causes inflammation of brain tissue.
Only one percent of those infected with the West Nile virus will develop severe illness. The fatality rate is only about 15 percent.
Meanwhile, Dayrit allayed fears of a possible outbreak of the still unknown disease. "There is no reason for them to panic. The disease is not contagious," he said. Freeman News Service, Rainier Allan Ronda and Miriam Garcia Desacada