At a time when less than 5 percent of the adult population in India is fully vaccinated, the vaccination drive needs all the positive reinforcement that it can get. What it definitely does not need is negative publicity and rumors fueling vaccine hesitancy.
Where on the one hand, there is acute vaccine shortage and a frenzy to book a slot through the COWIN
portal, there are paradoxically still vaccine centers which await vaccinees after all preparations.
With Covaxin being in short supply and the duration between two doses of Covishield increasing to a minimum of 84 days, our citizens are in a state of confusion and helplessness. Most affected are the NRIs and students who have to leave for resuming their work or study courses abroad and cannot wait for three months to get their second dose of Covishield which is the only vaccine from India recognised by the WHO as of now.
However, steps have begun in this direction with many states like Kerala, Maharashtra, Andhra Pradesh, Gujarat and Telangana starting a priority vaccination for this set and WHO approval for Covaxin
expected by September.
Obtaining two doses of the vaccine gives rise to a feeling of short-lived euphoria, after which realisation that the vaccines available in India are at best 80 percent efficacious makes us hope and pray that we are in that 80 percent protection cover. This only re-emphasises the continued importance of masking—the double the better, social distancing, avoiding crowds and poorly ventilated spaces, and hand hygiene.
Emerging data from hospitals in the past three months report 6-8 percent breakthrough infections (infections occurring in individuals after two weeks of the second dose of the vaccine) in healthcare workers which have been mostly mild to moderate demonstrating that the currently authorised vaccines do shield people from severe infection and hospitalisation. Vaccinated people are also less likely to transmit the virus to others.
Disturbing news of 594 doctors dying in the second wave points to exposure to higher viral loads for a prolonged period in the COVID-19 wards and ICU’s completely overwhelming the protection offered by the vaccine. Accompanying co-morbidities, mismanagement of some cases, oxygen or drug shortages and the black fungus infection could have been other contributors.
SARS-CoV-2 variants of concern have also played a crucial role in breaking through the barrier provided by the vaccines leading to infections. They have been recently redesignated by the WHO by Greek letters—Alpha ( B.1.1.7)—the UK variant, Beta ( B.1.351) from South Africa, Gamma from Brazil ( P1) and the Delta ( B.1.617.2) from India. These are more transmissible and at best 60 percent protective against the existing vaccines which could prove risky in individuals with lowered immunity or the elderly.
Of the total 25,739 COVID -19 positive samples sequenced by INSACOG (Indian SARS-COV-2 Genome Sequencing Consortia), 9,508 samples have been found to be variants of concern, of which 5261 are B.1.617( a whopping 55 percent) and of this, a majority has been the B.1.617.2 variant.
Emerging studies in healthcare workers indicate that high levels of IgG antibodies that are a surrogate to measuring the protective neutralising antibodies prevented breakthrough infection but more detailed research is required to clarify the duration of protection, requirement of boosters, the effect of mixing vaccines and the impact of the variants. Similar analysis of data is also needed from the breakthrough infections in the community for prediction and forecasting of the third wave.
Addressing the shortage of vaccines in India at this stage is paramount by smart procurement strategies through imports, advance booking, supporting a global patent waiver for manufacture, collaborations, and allowing ingress of mRNA vaccines into India.
Biological E in Hyderabad has teamed up with Providence Therapeutics in Canada to unleash its mRNA vaccine candidate and with Baylor, USA for imports of 30 crore vaccine dosages while Drug manufacturer Cipla is ensuring the entry of Moderna into India.
Pfizer and Moderna are in talks with the Government of India for indemnification against liabilities from usage. The mRNA vaccines are better for children as also for tweaking against variants.
Enabling combinations of vaccines after establishing safety and efficacy could also improve the logistics of administration. One of the largest ongoing trials in the UK by the Oxford Vaccine Group ( Com-CoV trail ) is studying the combination of a Pfizer or Covishield first dose followed by a Moderna or Novavax second dose. Earlier a Spanish study demonstrated a good immune response after the first dose of Covishield followed by a second dose of Pfizer after 8 weeks. Boosters
may become a reality.
Communication advocacy to address vaccine hesitancy will remain a priority in areas with low vaccine uptake. Vaccinating children and pregnant women after successful completion of ongoing trials would be highly desirable. Ramping up diagnostics, tracking and surveillance would ensure vaccine coverage where it is needed most.
Considering that the efficacy of the available vaccines in India is 80 percent, we would have to vaccinate at least 80 percent of our population including children to achieve herd immunity that would prevent or lessen the impact of the third wave. Also, ethics and equity of vaccine distribution should be practiced by making the vaccine easily accessible to the lower socioeconomic strata. Vaccination remains our only hope against severe disease and death due to COVID-19
— The authors, Dr. N.K Ganguly is the former Director-General, ICMR, and Dr. Namita Jaggi is the Chairperson, Labs and Infection control and Chief, Education and Research at Artemis Hospital, Gurgaon. Views expressed are personal
(Edited by : Ajay Vaishnav)