COVID brought about notable decrease in Influenza cases? Here's what researchers reveal

New research by Nature Reviews Microbiology revealed that the SARS-CoV-2 pandemic has significantly reduced the cases of influenza. According to the research published in September, the B/Yamagata lineage - a notable agent for flu viral infection - has not been reported from April 2020 to August 2021. As a result, the researchers are now saying that the seasonal flu virus might have become extinct. The researchers said that the cases of influenza dropped by 99%, despite roughly similar levels of testing. Notably, infection with the influenza B virus (IBV) accounts for around a quarter of the annual influenza burden.

"The genetic diversity of influenza viruses has also dramatically diminished. The number of cases detected has fallen for both influenza A (H3N2) and A (H1N1) subtypes, and, similarly, diversity has diminished for the B/Victoria lineage," noted the researchers. However, they stressed this is not the first time when such a case has been observed. The researchers noted that the viral infection if returned, there would be a larger scale of devastation. Citing an example, the observers noted during the 1990s the B/Victoria lineage was mostly undetected globally, except for an outbreak in Asia, but subsequently dominated global IBV isolates in the early 2000s.

What is the difference between influenza and COVID-19 virus?

According to World Health Organization (WHO), COVID-19 and influenza (flu) are both infectious respiratory diseases, and they share some similar symptoms. However, they are caused by different viruses, and there are some differences in who is most vulnerable to severe diseases. Both viruses share similar symptoms, including cough, runny nose, sore throat, fever, headache and fatigue. Both COVID-19 and influenza are spread by droplets and aerosols when an infected person coughs, sneezes, speaks, sings or breathes. People can also get infected with both COVID-19 and influenza by touching contaminated surfaces, then touching their eyes, nose or mouth without cleaning their hands. Though the researchers noted that there is a significant reduction in influenza cases, they appealed to people to take vaccines for both. 

What led to a reduction in Influenza cases?

As both COVID-19 and Influenza are airborne diseases, researchers noted that behavioural changes played a vital role in arresting the spread of the virus. They noted that the people across the world followed social distancing, mask-wearing and hygiene measures while moving out of the house, resulting in the reduction of cases. Moreover, the continuous lockdowns and strict COVID measures also played a major role in driving away from the influenza virus. "Influenza virus detections dropped dramatically from April 2020 with a ~99% reduction compared with previous years despite roughly similar levels of testing. Behavioural changes (social distancing, mask-wearing and hygiene measures) and travel and movement restrictions are thought to be the major factors driving the reduction in influenza incidence, which was also observed for other common respiratory infections such as respiratory syncytial virus," the paper added.

Can one get infected with COVID & influenza at the same time?

According to WHO, it is possible to catch both diseases at the same time. The most effective way to prevent hospitalisation and severe COVID-19 and influenza is vaccination for both diseases.

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