The government of Andhra Pradesh is now thinking of consulting the Center for Disease Control (CDC), a US agency, to identify the virus causing mystery fever in the state. The mystery fever has already claimed the lives of 212 children in the state so far (this latest figure was announced by Health Minister Dr Kodela Sivaprasada Rao), though official toll was put at around 120.

It is learnt that the government would approach foreign agencies if the National Institute of Communicable Diseases (NICD), New Delhi, and the National Institute of Virology, Pune, failed to come up with a diagnosis soon.

Meanwhile, the health authorities have asked the two national institutes to verify whether the viral fever sweeping the state is being caused by the West Nile Virus. " We have asked NICD and NIV to look into the matter. They have to confirm the presence of the West Nile Virus. The symptoms are similar to those seen in Meningo-Encephalitis," said In-Charge Director of Health Lakshmi Rajyam. Only three of the 60 odd samples sent to NICD had tested positive for Japanese Encephalitis. No results had been given for the remaining samples.

According to N C K Reddy, Supdt of Niloufer Hospital, the symptoms of encephalitis and West Nile Virus infection are quite similar. "But our conditions are very different from the places where West Nile Virus infection has broken out. Only the results of the NICD and NIV tests will confirm the cause of deaths," he said.

The West Nile Virus is spread through mosquitoes which also prey on birds, some of which could be infected.

Dr Jacob John, an expert from the Christian Medical College, Vellore, who visited Karimnagar and studied about 20 cases, said the viral fever could be Reye's Syndrome, which results in brain swelling, infection of the liver and kidneys and can lead to death. It tends to occur during recovery from a viral infection. Symptoms can include recurring vomiting, convulsion and loss of consciousness. This has been ruled out by Dr Nagabhushana Rao, a clinical expert in Japanese Encephalitis. He ruled out the West Nile virus, too. Though the government has declared a health emergency in the districts, overall trends indicate that the infection is still spreading.

According to reports, the district administrations are waging an unequal war against the unknown malady with a massive clean-up drive and doctors are administering symptomatic treatment to patients. For, the medical fraternity still does not know for sure what is causing the deadly fever.

The flow of suspected fever patients to hospitals remains almost unchecked. The doctors and staff of MGM Hospital, Warangal, had to attend to 18,000 children in the out-patient department during the last two weeks. The pressure on the private nursing homes also had been unprecedented. In the neighbouring Karimnagar, the picture remains just as grim. Public health centres and hospitals have so far treated as many as 23,000 patients.