Photo: Warren Goldswain
What is the flu?
Flu is short for influenza and is a contagious illness caused by a virus infection of the respiratory tract. There are many viruses that are responsible for flu, and many of them are also constantly mutating, which makes it very difficult for people to build immunity to the flu.
Because the flu spreads from person to person when they are close together, more people get sick when the weather turns cold. In India the highest number of cases of flu occur during the monsoon months. In most years there are several different strains of influenza viruses that affect people. Therefore the term “seasonal flu” or “common flu” is used to refer to illnesses caused by the influenza viruses. However, in some years one or two particular strains of influenza virus cause more illnesses than others, in which case those particular strains become cause for concern.
What is the H1N1 virus (“Swine flu”)?
Influenza occurs in other animals and birds as well. Several different influenza viruses that infect pigs also affect people, and one of those strains is H1N1. Others are H1N2, H2N2 and H3N2.
Northern India experienced an outbreak of H1N1 variant influenza in 2013 and another outbreak occurred late in 2014 and into 2015. Medical experts say this is to be expected following the H1N1 pandemic of 2009.
The H1N1 virus spreads among people the same way as other influenza viruses, but although it is called “Swine flu”, it does not spread from eating pork or other meat from pigs. The symptoms of H1N1 flu are the same as for seasonal flu. However, in some people, H1N1 flu can be more severe and lead to death. Unlike other flu strains which cause death more in people over 65 or in very young babies, H1N1 also severely affects people between 20 and 60. Since this is a new trend, it is cause for concern.