The year that has ended saw the world coming to grips with a new influenza pandemic after an interval of 40 years. It was not the much-feared H5N1 bird flu virus. Nor did outbreaks begin in East Asia, as was believed to be likely. Instead, the first human cases appeared in April on the other side of the globe. Thereafter, in a world interconnected by rapid air travel, the new virus showed up in country after country. By June, the World Health Organisation officially declared the start of the flu pandemic. Analysing the viral genome, scientists swiftly established that it had jumped to humans from pigs and possessed a mix of human, pig, and bird flu genes. Mercifully, the novel H1N1 strain has been quite unlike the one that set off the catastrophic 1918 pandemic. Swine flu, as the new virus is commonly called, infected many millions of people around the world during 2009. But the vast majority recovered easily. One key difference is that while seasonal flu predominantly kills the old, the new virus has proved life-threatening to younger people too. Pregnant women and people with chronic health conditions have been particularly at risk. Even healthy youth have sometimes fallen victim. Autopsies carried out on some of those who succumbed in New York showed that the pandemic strain was damaging cells all along the airway, including deep into the lungs. Bacterial co-infection greatly increased the risk of developing severe disease.
WHO’s assessment is that the true number of fatalities from the H1N1 virus worldwide was higher than the approximately 12,200 reported because many deaths would not have been recognised as flu-related. U.S. health officials recently estimated that 50 million Americans (a sixth of the country’s population) caught the disease, 213,000 needed hospitalisation, and nearly 10,000 died of the disease. In India, a young man who flew in from New York in May became the country’s first officially confirmed case. Three months later, the virus claimed the life of a Pune schoolgirl. Since then, more than 840 laboratory-confirmed deaths have been reported from various States. In South Asia, according to a recent WHO update, influenza activity continues to be intense, particularly in northern India, Nepal, and Sri Lanka. Although the moderate impact of the pandemic was the “best possible health news of the decade,” the world health body’s Director-General Margaret Chan has cautioned that it would be prudent to continue monitoring the virus’ evolution for another year. By focussing minds and resources, the pandemic has left the nations of the world better prepared to deal with global health emergencies.
