Pandemic response and the dilemma of vaccination

ANGLO-SWEDISH drug-maker Astra-Zeneca (AZ) has initiated the worldwide withdrawal of its Covid-19 vaccine. In India, the vaccine, known as Covishield, was manufactured in collaboration with AZ by the Pune-based Serum Institute of India (SII). Around 175 crore doses were administered across the country.

The vaccine’s withdrawal has been attributed to “the availability of multiple, variant vaccines leaving a surplus of outdated vaccines”. Simply put, it was just a business decision, coming on the heels of court proceedings related to cases of serious side effects and a £100-million class action lawsuit that the company faces. In February, the company is reported to have admitted that its Covid 19 vaccine “can, in very rare cases, cause TTS”.

TTS stands for thrombosis with thrombocytopenia syndrome. It causes low platelet count and formation of blood clots. Lay articles mention symptoms such as shortness of breath, chest pain, headaches and easy bruising.

Several people in the UK have claimed that they suffered various kinds of injuries. In India, too, some families are pursuing legal action against AZ and the SII.

Against this background, I weigh in on what public health dictates governments to do and whether anything could have been done differently in India.

I talked to two highly knowledgeable people, whose words are worth repeating before I give my views as a former public health administrator.

I first spoke to Dr Gagandeep Kang, one of India’s leading microbiologists and virologists, whom I had known when she was the Executive Director of the Translational, Health, Science and Technology Institute of the Ministry of Science and Technology. As she put it, the WHO announced the probable association of TTS with the AZ vaccine in March 2021 and confirmed it by May 2021. The SII had updated its vaccine label to include the risk for Covishield in October 2021. With TTS, we only know anecdotally that some patients reportedly faced side effects, and some cases eventually resulted in deaths. What was the risk-benefit of continuing or not continuing with the vaccination — or even warning millions of people? Did we have an alternative?

Answering these questions, Kang explained what is not widely known: “The risk is age-dependent and may also be geography-dependent. The latter can only be measured by doing pharmovigilance (safety monitoring of vaccines) either actively, as we have done for rotavirus vaccines, or passively, which is to wait for people to report a problem. The issue with the passive approach is that anything that does not occur within the first few hours or days after vaccination may not be recognised as having an association with vaccination.”

“The risk-benefit ratio, particularly for the Delta wave, was very high on the side of benefit, particularly for older individuals and somewhat less for younger ones. Had we followed the lead of the West and stopped Covishield among less than 40-year-olds, our alternative would have been Covaxin which was in short supply resulting in immunisation becoming very stretched out for younger people. Given the absence of any India-specific TTS data, it would have been difficult to monitor,” she said.

Dr Anand Krishnan, Professor at the Centre of Community Medicine at AIIMS, New Delhi, put it differently: “Larger public health interest mandated that a rare side effect did not derail a beneficial programme. Focusing on side effects could have resulted in high vaccine hesitancy. That does not mean we should hide it (the side effects)… In hindsight, it is easy to say that better, more nuanced and balanced communication would have helped. Maybe we could also have planned for compensation for those who encountered rare side effects.”

I have no hesitation in saying that the process of examining side effect claims would have presented a nightmare for state governments, whose resources were overstretched and fully committed to getting the vaccinations done with utmost expediency. When pandemics strike, public health professionals and governments the world over have to triage the population at risk and ensure that the most vulnerable get vaccinated on priority. In India, vaccination clearly prevented tens of thousands of people from dying or rushing to hospitals at a time when no beds were available.

The fact that the AZ vaccine was approved in just 10 months — in contrast to 10 years, which is the usual time taken to develop a vaccine — must not be lost sight of and must be recognised and saluted. It certainly prevented millions of people from succumbing to severe illnesses or dying. The situation would have been different had the severe side effects been well understood and not been overlooked by those who took decisions. But was that so? Was any negative advice given by any expert body suppressed? Was there anything essential and equally actionable that ought to have been shared with state governments? If not, the balance of advantage was clearly in favour of accelerating the vaccination drive.

We were fortunate we did not see a forceful anti-vaccine movement which could have impeded the gargantuan outreach needed to vaccinate India’s massive population. Dispersed across overcrowded cities and over six lakh villages, the public health response was naturally to prevent large-scale morbidity and mortality. That was non-negotiable. To expect families and communities to make a choice would have put millions at risk. In the absence of data on age or geography, it would have been a wild-goose chase which could have derailed the programme. District health workers in India’s 800-odd districts, having a population of about 20 lakh each, already had their hands full.

At times, the good (in this case, monitoring side effects), could have become the enemy of the great (vaccination of millions at risk). Indeed, for India, that is the moment of truth!