Delhi has recorded a sharp rise in cases of influenza H1N1 or swine flu this year, with 1,449 cases reported as of August 12, more than six times the 229 infections recorded during the corresponding period last year, according to National Centre for Disease Control (NCDC) data.“Of the 1,449 cases of H1N1 recorded so far this year, 63 were reported on August 11,” Delhi Health Minister Pankaj Singh told The Indian Express on Wednesday. In 2019, Delhi had recorded 3,637 H1N1 cases and 31 deaths.Singh maintained that Delhi government hospitals were equipped to deal with the situation. “There are special and separate wards in various Delhi hospitals like RML and Safdarjung to deal with the rise in cases,” he said.Dr S Chatterjee, internal medicine specialist at Apollo Hospital, said the reason for the current rise would be clear only after a genetic study of the virus. “Maybe the virus has mutated, or it’s happening because people are coming into contact with each other more,” he added.The H1N1 virus, commonly known as swine flu, is a type of influenza virus that causes a viral infection of the nose, throat and lungs.Influenza viruses are classified into four types – A, B, C and D. Among these, Influenza A is the most common type that spreads from pigs to people. Common symptoms include fever, cough, headache, muscle aches, tiredness, sweating and chills.Delhi has, meanwhile, also reported 184 cases of influenza B (Yamagata).Story continues below this adDr Chatterjee said H1N1 can sometimes progress quickly from a mild respiratory illness to a severe condition.“This year, from young to old, all age groups have been affected. People with weakened immunity and co-morbidities – like diabetes, hypertension, lung disease, heart disease – as well as pregnant women and elderly people, are more at risk.”There are a few cases, which have gone to respiratory failure as well, he said.“Treatment is symptomatic; antibiotics don’t really work. Only one antiviral drug, oseltamivir, works, but it only works when the treatment is started early. So, going to the doctor or getting tested becomes crucial,” he added.EPIDEMIC DISEASES ACT, 1897When can it be used?Story continues below this adThe Act allows the Union or state government to take special measures when an epidemic poses a serious threat to public health and existing laws are not enough to control it.What is Section 2?The state can take measures when it is satisfied that the ordinary provisions of law are not sufficient to control the epidemic, including segregating, inspecting and accommodating individuals or groups.Why was it enacted?The Act was passed in 1897, during British rule, amid an outbreak of bubonic plague in Bombay in 1896, which killed thousands.H1N1 precedentThe Act was invoked in several states in 2009 during the H1N1 outbreak. According to NCDC data, The first case was reported in Hyderabad on May 16, 2009. India recorded 10,193 cases and 1,035 deaths by May 24, 2010.Global pandemicStory continues below this adIn June 2009, the World Health Organization declared H1N1 a global pandemic, with over 74 countries affected.