New Delhi (NVI): Scientists in China have discovered a new type of swine flu with “pandemic potential”, a study published in the science journal PNAS has said. The flu is genetically descended from the H1N1, which caused hundreds of thousands of deaths in 2009, and is named G4.
G4 originated in Mexico and caused a worldwide epidemic in 2009.
Scientists at Chinese Universities and China’s Center for Disease Control and Prevention have observed that G4 viruses have all the essential hallmarks of a candidate pandemic virus. The tests have also shown that any immunity that humans gain from exposure to seasonal flu does not provide protection against G4.
Named G4 EA H1N1, the virus was detected after analysing 30,000 nasal swabs from pigs in slaughterhouses in 10 Chinese provinces between 2011 and 2018.
“Of concern is that swine workers show elevated seroprevalence for G4 virus,” the researchers note. They have said that controlling the prevailing G4 EA H1N1 viruses in pigs and close monitoring in human populations, especially the workers in swine industry, should be urgently implemented.
“Pigs are considered as important hosts or “mixing vessels” for the generation of pandemic influenza viruses. Systematic surveillance of influenza viruses in pigs is essential for early warning and preparedness for the next potential pandemic,” the scientists have said in the research article.
Swine flu was first recognised in the 1919 pandemic and still circulates as a seasonal flu virus. Swine flu is caused by the H1N1 virus strain, which started in pigs.
In 2009, the WHO declared H1N1 a pandemic. The infection is similar to seasonal influenza and symptoms include fever, chills and sore throat.
In India, the H1N1 virus outbreak had previously occurred during the 2009 flu pandemic. The virus killed 981 people in 2009 and 1,763 in 2010. However, the mortality decreased in 2011 to 75. It claimed 405 lives in 2012 and 699 lives in 2013. In 2014, a total of 218 people died from the H1N1 flu and India recorded 837 laboratory-confirmed cases in the year.
In 2015, India saw a significant swine flu outbreak, with nearly 30,000 confirmed cases and almost 3000 deaths by March 2015, according to the Ministry of Health. The worst affected states were Rajasthan, Gujarat and Delhi.