क्या कोरोना हमेशा हमारे साथ रहेगा...? Is corona staying with us forever...?

Author : Dr. P. D.GUPTA

(Former Director Grade Scientist, Centre for Cellular and Molecular Biology, Hyderabad, India)


For many people, catching the flu might not seem like that big of a deal — you might feel crummy, miss a few days of work or school, and then return to daily life. Nearly now happening this with Covid-19. 

But this common illness causes tens of thousands of hospitalizations, getting trillions of antibiotics antivirals tablets and vaccines shots even after this ten of thousands dies each year:   During three out of the four flu pandemics in the past two centuries, that number jumped into the millions worldwide.  Ending this disease would prevent countless deaths. But is it possible to eradicate the flu? 

The short answer is no, said Mark Slifka, an immunologist at the Oregon National Primate Research Center. The closest we came to this holy grail of epidemiology was in the 2020-2021 flu season — the first full winter of the coronavirus pandemic, when masking and isolating at home were more common, he said.   

"That's exciting, but it doesn't make much of a dent," Slifka said. With the return to air travel, school, work and regular socialization, the flu is back with great force, he said. As, it has come back not only in India but other places also. 

That's because influenza viruses, which cause the flu, constantly mutate, creating thousands of versions of themselves; these different versions of the viruses are called "variants" or "strains." If one strain disappears, "others just fill in," Slifka said. Each year brings new influenza variants, which requires a new vaccine if not for all the variants but some requires definitely a new vaccine.. That makes it difficult to manufacture a vaccine. To get ready for flu season, scientists have to predict which variants will be dominant in the upcoming season, based on which variants are circulating in humans in the opposite hemisphere. 

"It's a guess; sometimes they don't get it right," said Marc Jenkins, an immunologist at the University of Minnesota Medical School.  

Some years, the flu virus mutates so quickly that it outpaces vaccine manufacturers. By the time a shot is ready to be administered to the general population, it might not be very effective against the newest variants. And sometimes, the viruses used in the flu vaccine mutate during the manufacturing process; this means that the viruses aren't a "good match" by the time they're killed and added to the vaccine. As a result, the flu vaccine's effectiveness ranges from 10% to 60% from year to year.  In other words, a person who receives the flu vaccine has a 10% to 60% lower chance of getting the flu than someone who did not receive the vaccine. That effectiveness peaks one month after vaccination and then weakens over time, declining by roughly 10% each month. 

Some scientists are working on producing a universal flu vaccine — that is, a vaccine that would work against many possible variants of influenza.  However Nature is more powerful than human beings only time will tell, who wins. (The author has his own study and views)