CHENNAI: The city corporation's six diagnostic laboratories - in EVR Salai, Saidapet, Valluvar Kottam, Tiruvanmiyur, Perambur and Otteri - will draw samples from patients with H1N1 symptoms and send the same to the King Institute of Preventive Medicine for testing, according to corporation health officer P Kuganantham.

Addressing an orientation programme on H1N1 at Ripon Buildings on Tuesday, Kuganantham said that private medical practioners could refer cases with H1N1 symptoms to the laboratories and the latter would send the results to the authorites concerned, besides keeping doctors informed. "Physicians and corporate doctors are the major stakeholders in healthcare services and their cooperation is required in combating the spread of flu," Kuganantham said.

Since June, Chennai has recorded 138 cases with H1N1 symptoms, most of them international passengers or NRIs who had arrived from flu-affected countries such as Mexico, England, Australia, USA and Hong Kong. The virus has been spreading locally only the past two weeks. "It is a billion dollar question; our investigations are unable to provide us information on how people here really contracted the virus," Kuganantham said.

Symptoms of the H1N1 flu are similar to those of seasonal influenza, which infects people at least 20 times a year. In children, emergency warning signs that need urgent medical attention include trouble in breathing, bluish skin, fever with rashes, and symptoms showing signs of improvement but getting worse, with more fever and bad cough. Adults will have pain or pressure in the chest or abdomen, sudden dizziness, severe or persistent vomiting and difficulty in breathing.

"Adult patients can be discharged in seven days after symptoms subside; children can be discharged in 14. Patients discharged should be educated on personal hygiene and infection-control measures at home. Children should not attend school during the period," Kuganantham said. Medical practioneres have been advised to adhere to precautions such as washing of hands, covering of mouth and nose with a mask, scientific disposal of masks and sterilisation of instruments frequently used.

In case prolonged illness raises serious doubts, doctors can immediately notify the case to the local civic health authorities, to aid field-level intervention. Also, if medical practioners report with clinical evidences, the anti-viral drug, Tamiflu, will be made available. "Of the 17 positive cases getting treatment at the Communcable Diseases Hospital, Tondiarpet, five will be discharged on Wednesday and another four on Thursday," commissioner Rajesh Lakhoni said.