Making vaccines available to Indians may not be enough, it depends on how judiciously we employ them

• At the current rate (0.67 million per day), it will take at least 5.6 years to vaccinate the entire population with a single dose.
• India needs to ban the export of vaccines manufactured in India to ramp-up vaccine distribution.
• A massive effort is needed to vaccinate at least 10 million people per day that may have some dent in the virus’s ongoing intense transmission.

The fact that the second wave of Covid-19 pandemic has arrived in India can neither be denied nor overlooked. And the new wave seems to be more severe both in terms of infectivity and lethality if one goes by the initial data gathered from the states severely affected by this recent surge. More than 55,000 cases and 250 deaths have been reported as of March 26 — the highest so far this year.

Why the second surge?

Opinions may be divided on the exact reason behind this resurgence. Still, as more and more data are emanating, it seems the advent of the new and more infectious variants, mainly the UK variant having N501Y substitution and 69/70 deletion, may be the main reason behind these outbreaks in a few states. The limited gene sequencing data have already pointed toward the presence of two distinct variants, the UK and South African in Maharashtra and Punjab, the two most severely affected states.

The other reason could be laxity by both the Government and public in adhering to the non-pharmacological mitigation measures like masking, social distancing, avoiding gathering, etc.

Another important reason could be the secular changes in the epidemiology of the SARS-CoV-2 virus since the first 3-4 months of the year favours the dissemination of respiratory viruses in some Indian states like Maharashtra, Gujarat, etc. One should remember that globally also, many waves of Covid-19 outbreaks have been observed.

What impact did Covid vaccines have?

Now, it brings us to the critical question. What role did the Covid vaccines have in India’s ongoing fight with the virus? India gave emergency use authorisation to two Covid vaccines — Covishield and Covaxin — in the first week of January 2021 and started the first inoculation phase from 16th January. So far, around 50 million doses have been administered, and 8 million people have received both doses. At the current rate (0.67 million per day), it will take at least 5.6 years to vaccinate the entire population with a single dose. Even if we add the already infected (i.e., 12 million) to the tally, 4.4 years would be needed to vaccinate everyone. We all know that the current threshold to achieve herd immunity is 70%, provided vaccines offer 100% protection and prevent asymptomatic transmission. Also, this estimate is based on the old circulation variant (D614G). Even this target (70%) would be reached in four years even with a single dose, and more than 20 years with the current pace. This means the impact of vaccination would be minimal until we cover a sizable proportion of our population. And by that time, the pandemic would have run its course. So, in all probability, the role of mass-scale vaccination would become redundant.

Globally also barring one country, Israel, that has vaccinated more than 51% of its population with two doses, no other country has shown significant Covid vaccination. In the UK, where the new variant has caused a massive second wave in the last quarter of 2020, it was a strict lockdown that had maximum impact on the pace of the pandemic, though vaccination had some effect on the older population. Similarly, in the US, the virus’s natural epidemiological variation led to the waning of the third wave of their epidemic. However, one can ascribe the minimal impact of mass vaccination in large countries like the UK and US with a partial vaccination of the susceptible population. The most glaring example of the failure of large-scale vaccination is offered by Chile, where despite vaccinating one-third of its people with a single dose and lying in the top three countries as far as vaccination per capita is concerned, it suffered another massive surge.


How to make vaccines relevant to our fight against the Covid pandemic?

So, will Covid vaccines fail to curb the ongoing pandemic? No, it depends on how judiciously we employ them. There is an intense competition between the pace of vaccination and the steady speed of virus spread. So far, the virus seems to be having the upper hand, and it is propelled by the assistance offered by its ongoing evolutions into more efficient forms.

As far as India, the second-most-populous country in the world, is concerned, it seems handicapped by its inability to vaccinate quickly. Following measures may help to make vaccinations count as an effective intervention against the ongoing pandemic rather than as a redundant exercise:

1. Ramping up considerably the pace of vaccination: As described above, the current vaccination rate is sluggish. A massive effort is needed to vaccinate at least 10 million people per day that may have some dent in the virus’s ongoing intense transmission. At this rate, we can vaccinate a sizeable chunk of our population within 3-4 months that may halt the ongoing transmission. India can do this -- during the polio supplementary immunisation activities, India had vaccinated around 170 million children during a round of vaccination. The vaccination at the current pace will lead to significant immunity gaps that may facilitate viral mutations.

2. Ban on export of vaccines manufactured in India: A critical hindrance to the rapid ramp-up of vaccine distribution would be the limited supply of vaccines. India may need at least 1.5 billion doses for its domestic use. On March 25th, India put a temporary hold on all major exports of two indigenously produced vaccines. This is a step in the right direction considering ongoing intense viral transmission. However, another important vaccine, Covovax, originally developed by Novavax and produced here by the Serum Institute of India, is also needed to be prioritised for domestic use, and export should be deferred. This candidate has proved to have excellent efficacy and ease of production with tremendous scalability. Owing to these essential virtues, this candidate is the key to vaccinating the entire globe, not the mRNA or vector-based vaccines.

3. Need to fast-track the regulatory approval of Covid vaccines: Currently, Indian regulators have made it mandatory to conduct bridging studies in India for emergency use authorisation of even a proven product. Though this may add a certain value, this may prove to delay the vaccines’ roll-out amid an intense outbreak. Those vaccines that have already proven their efficacy amongst different populations need to provide a waiver. For example, few key vaccines like Novavax’s protein sub-unit, Sputnik-V and Janssen’s Ad26 vector vaccines, are being produced here by some Indian companies. All these vaccines have proven their efficacy globally, and two of them are in use in many countries. They should be made available for domestic use.

4. Rescheduling the administration schedule: Recently, the government of India announced a prolonged time interval between the first and second dose of the Covishield vaccine from 4 weeks to 6-8 weeks. However, the recent trial of the Covishield demonstrates that a 12 weeks interval provides a higher efficacy (up to 81%) than at 6-8 weeks (60-64%). Furthermore, even single-dose protection may last up to 12 weeks with a reasonably good efficacy (76%). Similarly, the dosing schedule of inactivated vaccine, Covaxin, can be prolonged to 8 weeks since immunologically, a higher interval between two doses provides better immunity. Hence, it would be more fruitful to delay the second dose administration to enable a massive inoculation drive in the shortest possible time.

5. Abolish prioritisation for vaccination: The current government strategy, which is based on the WHO directive, is providing hindrance to rapid vaccination of the entire susceptible population. Covid immunisation should be made accessible for all on a war footing level.

6. Spread vaccine delivery points: Though the existing government distribution system can vaccinate 10 million individuals per day, nevertheless expanding the vaccine delivery booths at certain entry points like at airports, bus, railway stations, etc., may expedite this drive. Even mobile vaccine booths can be developed across the country.

7. Speeding up the genetic sequencing: Currently, only a few thousand samples have been sequenced genetically. Only a few hundred samples are taken up for genetic sequencing in a few large states like UP. Following the confirmation of a few variants in the country, there is an urgent need to ramp up the sequencing and study the vaccine efficacy against these emerging variants.

The above-listed measures may help deliver Covid vaccines to a significant proportion of the population in the shortest possible time. To vaccinate the entire country over a few years may not serve any purpose. We need to utilise vaccines' availability to serve the purpose for which they were produced in a record time to end this pandemic.

Dr. Vipin M. Vashishtha is the former convener at the Indian Academy of Pediatrics (IAP) Committee on Immunisation, and a Pediatrician at Mangla Hospital and Research Centre in Bijnor, Uttar Pradesh

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