Washington: Strong protection against the SARS-CoV-2 virus with vaccination is short-lived and dependable protection against reinfection requires up-to-date boosters with vaccines that are adapted to address changes in the virus that occur as part of its natural evolution over time, says a new study. The research published in the research of the ‘Proceedings of the National Academy of Sciences’ (PNAS) on June 15, a study explains how vaccines create a longer immunity than antibodies from infection, and therefore booster shots are necessary.
The study explores differences in the duration of immunity to SARS-CoV-2 from vaccines and natural infection based on waning antibody levels. The public health response to continued outbreaks of SARS-CoV-2 requires an understanding of the durability of immunity conferred by vaccines and natural infection, the ideal timing for boosters, and the likelihood of breakthrough infections.
Jeffrey P. Townsend and colleagues estimated the durability of immunity and the likelihood of breakthrough infections over time using comparative evolutionary analysis.
The authors used the relatedness of the coronaviruses to integrate long-term immunological data from endemic coronavirus infections, reinfection data from close human-infecting relatives of SARS-CoV-2, waning antibody levels after natural infection from zoonotic coronaviruses, and immunological data following SARS-CoV-2 vaccination. The analyses incorporated trends in anti-spike protein IgG antibody levels over time following vaccination with four common SARS-CoV-2 vaccines.
Natural infection conferred a median of 21.5 months of protection from breakthrough infection, whereas mRNA vaccines produced by Pfizer-BioNTech and Moderna elicited antibody levels higher than natural infection, leading to a median time to breakthrough infection of 29.6 months.
The authors found that viral vector vaccines produced by Oxford-AstraZeneca and Johnson & Johnson/Janssen elicited antibody levels similar to those elicited by natural infection, with median times to breakthrough infection of 22.4 months and 20.5 months, respectively. According to the authors, the results demonstrate the need for booster vaccination in curtailing breakthrough infections and reinfections.
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NDTV – Dettol have been working towards a clean and healthy India since 2014 via the Banega Swachh India initiative, which is helmed by Campaign Ambassador Amitabh Bachchan. The campaign aims to highlight the inter-dependency of humans and the environment, and of humans on one another with the focus on One Health, One Planet, One Future – Leaving No One Behind. It stresses on the need to take care of, and consider, everyone’s health in India – especially vulnerable communities – the LGBTQ population, indigenous people, India’s different tribes, ethnic and linguistic minorities, people with disabilities, migrants, geographically remote populations, gender and sexual minorities. In wake of the current COVID-19 pandemic, the need for WASH (Water, Sanitation and Hygiene) is reaffirmed as handwashing is one of the ways to prevent Coronavirus infection and other diseases. The campaign will continue to raise awareness on the same along with focussing on the importance of nutrition and healthcare for women and children, fight malnutrition, mental wellbeing, self care, science and health, adolescent health & gender awareness. Along with the health of people, the campaign has realised the need to also take care of the health of the eco-system. Our environment is fragile due to human activity, which is not only over-exploiting available resources, but also generating immense pollution as a result of using and extracting those resources. The imbalance has also led to immense biodiversity loss that has caused one of the biggest threats to human survival – climate change. It has now been described as a “code red for humanity.” The campaign will continue to cover issues like air pollution, waste management, plastic ban, manual scavenging and sanitation workers and menstrual hygiene. Banega Swasth India will also be taking forward the dream of Swasth Bharat, the campaign feels that only a Swachh or clean India where toilets are used and open defecation free (ODF) status achieved as part of the Swachh Bharat Abhiyan launched by Prime Minister Narendra Modi in 2014, can eradicate diseases like diahorrea and the country can become a Swasth or healthy India.