In this study, published in Science, an examination of the variables which will determine the trajectory of the pandemic has been made.

The authors calculate the effects of pharmaceutical (diagnostic tests, vaccines, and anti-viral drugs) and non-pharmaceutical interventions (masks, quarantines, lockdowns) that predict the course of the pandemic over the next five years. Key variables of natural infection include the strength and duration of protective antibody responses to natural infections.

“If SARS-CoV-2 behaves like the cold-causing coronaviruses, then Covid-19 will become a recurring annual pandemic much like influenza but with greater mortality.”

If SARS-CoV-2 behaves like the cold-causing coronaviruses, then Covid-19 will become a recurring annual pandemic much like influenza but with greater mortality. Pharmaceutical and non-pharmaceutical interventions can modulate such an outcome. Key variables of the vaccines include the efficacy of protection from infection, disease, and transmission, the duration of the protective response, the fraction of the population vaccinated the extent of prior infections in the population, and the size of viral reservoirs both human and animals. Each of these variables will determine how serious a threat Covid-19 remains to human health and to economies.

“Their findings highlight the importance of immunological characterization beyond the measurement of active infections for adequately projecting the immune landscape generated by SARS-CoV-2 infections.”

The scientists use simple epidemiological models to explore estimates for the magnitude and timing of future COVID-19 cases, given different assumptions regarding the protective efficacy and duration of the adaptive immune response to SARS-CoV-2, as well as its interaction with vaccines and nonpharmaceutical interventions.

They find that variations in the immune response to primary SARS-CoV-2 infections and a potential vaccine can lead to markedly different immune landscapes and burdens of critically severe cases, ranging from sustained epidemics to near elimination. Their findings illustrate likely complexities in future COVID-19 dynamics and highlight the importance of immunological characterization beyond the measurement of active infections for adequately projecting the immune landscape generated by SARS-CoV-2 infections.

Read the full article in Science here!

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