Continuing COVID vaccination will break the chain of virus transmission: myth or reality

Achhelal R. Pasi


As countries roll out vaccines that prevent COVID-19, many scientists are reluctant to say with certainty that the vaccines prevent person to person transmission. All the vaccines authorised for emergency use do this,however there are no conclusive evidence that the COVID-19 vaccine prevents the infection. The limited data available suggests that the vaccines will at least partly reduce transmission, and the studies to determine this with more clarity are underway. One should wait for more data and conclusive evidence to make a statement like “ongoing COVID vaccination will break the chain of transmission”. A vaccine that is highly effective at preventing people from acquiring infection would help to reduce transmission, and till then we need to follow the COVID prevention measures. The best way to prevent infection from COVID-19 is to avoid exposure to the virus.a

COVID-19 is the disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) whose main mode of transmission between people, is when an infected person is in close contact with another person, apart from fomite and airborne transmission. Infection occurs when virus enters in the body and begin to multiply while disease occurs when the cells in the body are damaged — as a result of the infection — and signs and symptoms of an illness appear. Approximately 40% to 45% of those infected with SARS-CoV-2 remain asymptomatic and asymptomatic persons can transmit SARS-CoV-2 to others. Asymptomatic SARS-CoV-2 infections have been demonstrated to present with viral loads similar to symptomatic infections. Contact tracing and modelling studies suggest presymptomatic and asymptomatic patients are responsible for approximately 50% of all COVID-19 transmission events.


COVID-19, SARS-CoV-2, COVID-19 vaccine, Chain of transmission, COVID prevention

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