A growing, nationwide problem of booster lag
- The third dose is important because immunity from the two doses wanes after a while.
It has been nearly two months since the government allowed all adults to take a booster jab of a Covid-19 vaccine and people are not exactly queuing up in large numbers for their third shot. The third dose is important because immunity from the two doses wanes after a while. A district-level analysis shows this problem is widespread and worsening over time. Solving this problem might require efforts in more than one direction.
Even with a two-week delay, the booster problem is worsening
All adults became eligible for boosters on April 10. As on that day, 71.3 million people who had taken a second dose by July 10, were eligible for a third in keeping with the mandated nine-month gap. Since then, this number has increased – and the proportion of those availing a third dose, decreasing, as pointed out in an earlier HT analysis. (https://bit.ly/3Mgfonf)
Is it possible that some people are delaying their booster shots? Even allowing for a two-week gap from the first day of eligibility does not improve the figures much. Of the 79.5 million people fully vaccinated by July 16 last year, 52.5 million (66.1%) did not receive the booster by April 30. The situation has worsened by the end of May. Of the 120.2 million fully vaccinated by August 15 last year, 86.5 million (72%) were not boosted by May 30.
Delayed boosters are a nationwide problem
Apart from worsening over time, people missing their boosters is also a pan-India problem. By May 30, in half the districts of the country, 80% or more of those eligible had not taken their booster dose. In a full three-fourths of the districts, this share was above 72%. And in 90% of the districts, the proportion was above 66%.
Is the difference in booster coverage because of low or high base?
While most districts are doing badly on this count, are some doing relatively better just because they have a low share of eligible adults? For example, districts in Gujarat, Uttar Pradesh, Bihar, West Bengal, Odisha and Andhra Pradesh are performing relatively better. They were performing relatively worse in second-dose coverage nine months ago.
However, this is not the case when one looks at the entire country. The correlation between the share of adults eligible for boosters and the booster coverage is weak at the national level. For example, only 10.9% of Tamil Nadu was fully vaccinated nine months ago. Yet, 83.4% of the eligible people in the state have missed their booster shot. Punjab, parts of Maharashtra and Madhya Pradesh are in a similar category.
Are free vaccines making people turn up for boosters?
Given that large parts of the country are poor, free vaccines ensure people do not bear economic pain to protect themselves against the pandemic. However, as far as uptake of boosters are concerned, it is difficult to say if just making vaccines free helps. For example, boosters are free in both Delhi and Haryana. Although they have a similar share of eligible population – 27% adults in Delhi and 23% in Haryana – 71% have missed boosters in Delhi, compared to 83% in Haryana.
Can increasing the number of vaccination sites help?
There were 192 districts with up to 40 sites per million adults in the week ending August 30 last year (nine months ago) and 436 that had more than 40 sites per million. In the week ending May 30, districts in these categories were 303 and 325.
It is possible that increasing the number of sites will help. Consider Haryana, which is performing poorly on booster coverage. Ten of its 21 districts are in the under-40 sites per million adults category now compared to four earlier. On the other hand, 10 districts in Bihar and seven in Odisha, states performing relatively better, had only up to 20 sites per million population nine months ago. Such districts now number slightly less there – six and four, respectively.
None of the interventions may work in isolation, but it should be expected that states that make vaccines both free and accessible will surge ahead in terms of administering booster shots.