COVID-19: Flexible, agile vaccination strategy vital in saving lives in India, says Lancet report

Flexible and agile vaccination strategies can play a vital role in protecting lives in India as COVID-19 pandemic continues to unfold, according to a latest Lancet report.

The report 'Responsive and Agile Vaccination Strategies Against COVID-19 in India' published by the Lancet Global Health on Friday highlighted the importance of sentinel site based surveillance and detection of early warning signal through test positivity ratio (TPR).

Our analysis offers a demonstration of principle that even limited vaccination resources could be marshalled for maximum impact, if deployed flexibly in response to a rapidly evolving epidemic, the report said.

It said the experience from influenza pandemics in 1918 and 2009, as well as the current COVID-19 pandemic in other countries, highlight the potential for not just two, but subsequent waves of infection.

Flexible, agile vaccination strategies could thus play an important part in protecting lives and livelihoods as the COVID-19 pandemic continues to unfold, it said.

The report noted that innovative measures currently being tried in India like establishing satellite vaccination centres closer to hamlets in rural settings and resident welfare associations in urban areas; converting community halls and using large parking spaces for drive-in vaccination; and using mobile vaccination facilities to cover populations that do not live within easy access of vaccination centres.

Such community-based outreach activities, along with transport facilities for older and less physically able individuals (from their homes to satellite vaccination sites), will reduce the distance between main vaccination session sites and the potential recipients.

Active engagement of community-based organisations in such planning and execution will also be crucial, not only for successful implementation of vaccination, but also in addressing vaccine hesitancy, it said.

It further said that as India has already administered 199 million doses of vaccine, and records for adverse events following immunisation have reassuringly captured a very low rate of side-effects , the possibility of shortening the observation period following vaccination is being discussed.

Such measures will help to speed up vaccination while maintaining safety, it said.

It also noted that there is a mixed picture on single dose efficacy of currently available vaccines against B.1.617.2, the dominant COVID-19 variant in India.

Currently, there is a mixed picture on single-dose efficacy of currently available vaccines against B.1.617.2, the dominant variant now circulating in India. Early findings from the UK suggest that for ChAdOx1 nCoV-19, single-dose efficacy against this variant is substantially reduced when considering symptomatic infection as an endpoint.

However, more recent findings suggest that protection against hospitalisation is as high as 71 per cent. Similarly, single-dose protection against hospitalisation has been reported among healthcare workers in India, the report said.

It also stated that additional analysis illustrates that rapid-response vaccination could still have a substantial effect on deaths, even if single-dose vaccine efficacy were reduced to 30 per cent.

The Lancet report suggested that a strategy might be pre-emptively to identify and vaccinate those districts most at risk of resurgence-through serological surveys to identify regions with lower levels of previous exposure.

However, predicting risk in this way is far from straightforward; for example, major cities such as Mumbai and New Delhi were among the cities with the highest seroprevalence in India's first wave, and yet were the first to see resurgence in the ongoing second wave.

It will be important to adjust for population density and other factors to make systematic comparisons of seroprevalence across different regions, but collection of the necessary evidence will take time. In the immediate term, more rapidly deployable strategies are urgently needed, it added.