Mumbai: The number of swine flu cases in the city showed a whopping rise in 2019, going from 25 cases and zero deaths in 2018 to 448 cases and five deaths until November 2019, according to statistics provided by the public health department of the Brihanmumbai Municipal Corporation (BMC). Medical experts have blamed the prolonged rainy season for this surge, saying it made some strains of the H1N1 virus predominant, leading to an increase in transmission.
Health officials also attribute the increase in the number of cases to better surveillance. The highest number of cases were reported in May and July 2019, with a 1692 per cent rise in cases as compared to 2018. “The unprecedented rain in November created an atmosphere favourable for the H1N1 virus to not just multiply but evolve into a stronger strain. There was also an antigenic shift which affected many people. Moreover, there was better surveillance and reporting of cases,” he said.
To prevent the spread of the infection, 30,000 people from the vulnerable category - diabetics, pregnant women, hypertensive and elderly patients have been vaccinated.
“When there is a swine flu epidemic, those affected develop resistance to that particular viral strain, so for a year or almost two, there are fewer patients. Research is called for, to analyse the trend which suggests cyclic change,” said Dr Om Srivastava, infectious disease expert.
According to the World Health Organisation (WHO), for prevention of swine flu, a trivalent or quadrivalent intramuscular vaccine should be administered to those who are most susceptible, before the monsoon. Prompt testing for swine flu and immediate medical attention when symptoms are present is very important to avoid complications, according to WHO.
Year Cases Deaths
2015 3,029 52
2016 3 0
2017 995 18
2018 25 0
2019 448 5