Tuesday, June 23, 2009

India-Alarm over flu free run

New Delhi, June 23: The domestic air and rail journeys by a man infected with the H1N1 pandemic flu virus may have pushed the infection in India closer to the tipping point of community spread than ever before, public health experts said.

The 24-year-old in Pune who had developed fever and cough on June 16 a day after arriving from the US had flown to Delhi and taken a train to Lucknow for a two-day vacation before returning to Pune where he was found positive for H1N1.

As reported in The Telegraph today, his movements while infected have generated concern among government health officials who have been trying to prevent the spread of the virus in India by isolating infected persons.

Health officials said they would try to trace other passengers who had travelled with him aboard flights from Pune to Delhi and back, and who were in his compartment on the Lucknow Mail from Delhi to Lucknow and the Shatabdi on his way back to Delhi.

“We are worried,” said a senior health official. But officials say there are also reasons for optimism. “The (H1N1) virus has been causing only mild illness in most of the people infected so far,” an official said. And studies on transmission potential of this virus in North America and Japan suggest that a single primary infected patient can lead at most to one or two secondary cases.

Health officials have detected 68 H1N1 cases, all but seven in persons who had arrived from other countries.

The seven “indigenous” cases had picked it up from their infected relatives who had travelled abroad.

But the potentially large number of people who could have been exposed to the man during his travel to Lucknow last week has raised fears of community spread of the virus.

We’ll wait and watch... we’ll know it’s happening if we begin to see clusters of infections,” a medical officer said.

Community spread is a tipping point that may require changes in diagnosis and treatment policy. With community spread, flu diagnosis may not be possible, or even required, in every individual case.

Community spread of mild infection may also lead health authorities and doctors to follow a policy of providing the anti-viral drug oseltamivir only to patients with lower respiratory disease.

There are conflicting versions of what happened in Lucknow.

The medical officer co-ordinating the surveillance and containment effort in Uttar Pradesh said the man had been referred by a local clinic to present himself at the Balrampur Hospital Lucknow, the designated facility for isolating suspects with H1N1.

“But he did not go to the hospital. We tried repeatedly to contact the man or his family through their mobile phones, but the calls were unanswered or cut off,” said Pyaremohan Srivastava, the nodal officer in Lucknow.

“When we rushed to his house, he had already left,” Srivastava told said.

However, the boy’s father, when contacted by The Telegraph, said the family did not know whom to approach for diagnosis in Lucknow. “There was a delay because of our ignorance, but he had only mild fever,” the father said.

The man, who is a professional in a software company, walked into Naidu Hospital in Pune on June 20. He has told state medical officers in Pune that he travelled to Lucknow for a short vacation. “He is fine now,” an official said.

An infected person is likely to shed flu viruses by coughing or sneezing. Aerosols carrying influenza viruses have a travel distance of about a metre, said Jacob John, former head of virology at Christian Medical College, Vellore.

The hot weather in India now, which causes aerosols to evaporate, may reduce efficiency of spread, John said. But the aerosols could persist in air-conditioned train compartments.

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