Four children, all below 10 months of age, died after being administered measles vaccine at Pennaloorpettai and Venkatapuram villages in Tiruvallur district near Chennai on Wednesday. Another 15 children have been hospitalised after developing anaphylaxis reaction after being administered the vaccine, sources in the Public Health Department said. "No problems have been reported from other parts of the district where the immunisation drive was on. We are yet to pinpoint the exact cause of the deaths, and a final word can be given only after the lab test result of the vaccine and the post-mortem of the babies are conducted,' said a senior official. The vaccine samples have been sent to the Central Research Institute of India in Kasauli, Himachal Pradesh. The deceased children