Why vaccinating the frontline workforce should be prioritized
India’s Covid-19 vaccination roll-out model is based on population distribution and needs to be urgently changed to vaccinating the entire frontline workforce on priority.
The current Covid-19 vaccination roll-out model was by state, with the number of doses allocated to each state based on population distribution and contingent on the capacity of the state to administer the doses within their existing public healthcare infrastructure.
However, as the vaccination drive, prior to April 30, primarily targeted the 45+ age group, some of India’s most populous states received a far smaller share of the available doses than you might expect. To understand why, you need only look at data from the most recent Indian Census in 2011, which shows Uttar Pradesh and Bihar, which rank first and third among India’s most populous states, as having the lowest median age of all states within India.
Mathematically, the current population-based distribution model for vaccination roll-out is unable to control the spread of the virus. This suggests we need to adopt a different model to tackle this problem.
In epidemiological terms, R0 (referred to as “R naught”) is a mathematical term that indicates how contagious an infectious disease is. It’s also referred to as the reproduction number. As an infection is transmitted to new people, it reproduces itself.
For example, in 1918, a worldwide outbreak of an H1N1 virus (now commonly referred to as Spanish influenza) killed 50 million people. According to a review article published in BMC Medicine, the R0 value of the 1918 pandemic was estimated to be between 1.4 and 2.8. As of April 27, 2021, the current R0 for India is 1.56, according to analysis by epidemiologist Dr Giridhar R Babu from the Indian Institute for Public Health. In Telangana, the R0 saw a rapid increase from 1.47 on April 29 to 1.55 on May 1.
With vaccinations in progress across India, the effective reproduction rate R would be equal to R = R0*s where s is the percentage of people who are not vaccinated or susceptible to disease. With less than 10% of the population vaccinated, the effective reproduction rate in India will not decrease significantly for some time as there is shortage of vaccinations and more people are being exposed to the virus.
The Indian Government’s decision to de-centralize the procurement of vaccines in April 2021, to allow states to take this up on their own, was a response to vaccine shortages rather than a solution.
With state governments hesitant to implement lockdowns due to the country’s slowing economy, the only sensible solution is use the limited vaccinations we have to vaccinate and protect the frontline workforce, those who routinely come into contact with more than 5 to 10 people per day. In addition to medical staff, this would include frontline police, journalists, shopkeepers and even bank staff. This would be particularly useful in highly dense urban and peri-urban areas of India where these frontline workers who could be potential super spreaders. Adopting this strategy could dramatically reduce R0 and serve to bring the current situation under control.