Previously published in GRAPH Website
Editor’s note:
[Author is the professor and head of the Community Medicine, DY Patil Medical College, Pune. He is a prolific writer and regularly contributes to the National Herald. His in-depth analysis from epidemiological viewpoint deals with the pitfalls and fallacies of a skewed public health policy. He urges the authorities to adopt a sound public health policy based on scientific rationale and pragmatism. It needs to be emphasized that the covid vaccines have not yet passed through the phase 3 trial which is to be completed in 2023. The efficacy data is debatable and less than inspiring confidence of public and scientific community. The safety trial data in terms of short and long term side effects is conspicuous by it’s absence in public domain.]
Highlights:
• Vaccine policy should be guided by logistics and epidemiological data.
• Vaccinating young adults and children will not be cost-effective.
• Unplanned and haphazard vaccination can promote mutant strains.
• People who recover from natural infection should not be vaccinated.
• On basis of current epidemiology of Covid-19, eradication will not be feasible and we should settle for control. Case for mass vaccination weak.
• Launching vaccination for children against Covid will divert resources from other immediate and bigger child health problems in the country.
• Against above background should restrict vaccine to only those > 45 yrs and others having co-morbidities or obesity.
1. Vaccine an important weapon against the pandemic should be used judiciously.
Vaccine is a strong and powerful weapon against the novel coronavirus. A marvel of modern precision and genomic technology. And like all strong weapons it should not be withheld nor used indiscriminately but should be employed strategically to derive maximum benefit in a cost-effective way. We should be conversant with the benefits as well as the hazard of this potent tool.
The present situation of the pandemic in the country demands that we should be guided by the logistics and epidemiological data to prioritize vaccination rather than opening vaccination for all age groups at this stage. Opening all fronts simultaneously will drain our army of health workers and resources and would be spreading it too thin to make an impact given our large population.
“Therefore those who are not thoroughly aware of the disadvantages in the use of arms cannot be thoroughly aware of the advantages in the use of arms.”
Sun Tzu, ancient Chinese General and Philosopher (Art of War).
Vaccination of young adults and children is not supported by evidence and would not be cost effective. Unplanned vaccination can promote mutant strains.
Opening up the vaccination to younger adults right now will be a gamble with lives. This statement was made by Dr N K Arora, Head, Operations Research Group at the ICMR. [1] This opinion is supported by the logistic challenges and the science behind the strategy. We should strive to reduce deaths and hospitalization from the infection. So vaccinating young adults without comorbidities who are at negligible risks of serious disease or death will not be cost-effective. What needs to be done is to prevent deaths in older age groups and people with co-morbidities or obesity. Moreover as the long term side effects of the vaccines are unknown it is hazardous to include children and pregnant women in mass vaccination campaigns.
Mass, indiscriminate and incomplete vaccination can also trigger mutant strains. [2] Moreover, due to the recent second wave in our country, a large proportion of our population have already acquired immunity from natural infection. Fortunately most infections in young adults and children are asymptomatic or mild. [3] Against this landscape, it is wasteful use of limited resources to go for mass scale population vaccination of all above 18 years in our country. Presently we can restrict vaccination to adults aged 45 years and above on a voluntary basis and selectively vaccinate younger adults with gross obesity or co-morbidities.
2. People who have recovered from natural infection should not be vaccinated.
We can conserve considerable resources if we exclude adults who have recovered from natural infection. According to the third round of the national level serosurvey by the ICMR, about 21% of our population had already encountered the virus during the first wave.[4] Given the speed of spread of the second wave and its scale, it is very likely that another 30-50% of the population will be infected before the vaccine reaches them. At the end of the second wave we can tentatively expect that about 70-80% of our population may reach some level of population level immunity due to th e natural infection. Given the present state of knowledge there is no scientific logic to vaccinate those who have recovered from natural infection whatever the ‘experts’ opine based on conjectures and not on real world hard data or basic principles of immunology. So far a number of papers point to fairly long lasting and robust immunity after recovery from natural infection. [5-11]
There are other reasons why we should roll out vaccination cautiously, one group of the population at a time. If millions are vaccinated at fast pace with limited resources for monitoring of adverse events following immunization (AEFI), some adverse events and deaths which may be purely coincidental may cause negative publicity and increase "vaccine hesitancy." This would be a setback which would make it difficult to roll out vaccine to even the vulnerable and at risk in the future.
To practice and follow hard science we should go for country wide serosurveys once the second wave is over for estimating the population level immunity. We should refrain from vaccinating those with antibodies and also who have had a positive RT-PCR report in the past. This can save lot of vaccines and resources which can be focused on those who really need the vaccine such as health care workers, front line workers, the elderly and people with co-morbidities and obesity. To continue the science we can follow large cohorts who have recovered from past infections to see whether they can get re-infected. We can always revise our vaccination policy guided by science if we find an appreciable number of re-infections which are serious enough. This exercise will also confirm or refute earlier studies which indicated robust and long lasting immunity following natural infection. [5-11]
3. Vaccine policy should conform to overall strategy: control vis-a-vis eradication.
The vaccination policy should also conform to the overall strategy, i.e. whether we are going for eradication or control. Mass vaccination including all age groups is justified when we are going for disease eradication. Given the nature of the coronavirus where asymptomatic infections far outnumber cases, sophisticated test is required for diagnosis, community transmission is rampant, it is realistic to concede that eradication is impossible and settle for control. When control is the aim we should reconcile with vaccinating the vulnerable and at risk instead of mass population wide immunization including children as is being recommended by some professional associations and lobbies. Our country has much bigger child health problems causing more than 2000 deaths of under five children daily from preventable causes.
Attempting to control transmission of Covid-19 in children, which has almost zero morbidity and mortality in this age group, [3] will divert resources from more important child health problems leading to more deaths from other causes in this group than lives saved from covid in children (when to begin with mortality from covid-19 in children is almost zero). Besides, without establishing the effectiveness of the vaccines under field conditions investing in mass scale vaccination will be a costly gambit.
4. Need a public health perspective instead of a clinical one to cope with public health challenges
Diseases do not read textbooks. In every disease there are outlier cases which fascinate the clinicians and discussed at length at clinical meetings and published in medical journals. Over the years, perception of clinicians, particularly those practicing in ivory towers of medicine, the tertiary health care centres, is distorted by these outliers which become the norm for them. Present day media has joined in highlighting these cases which attract attention and spread panic among the lay public. Public health policy should be dictated by the less fascinating majority of cases, the normal distribution, so to say, which never draws attention or brings fame. The fact is that the novel coronavirus in India has an infection fatality rate of 0.1% or less. One has to do trade-offs in balancing scarce resources around this figure. This is sound public health policy. Regrettably, in the present pandemic celebrity clinicians have been advising most governments instead of public health specialists and epidemiologists.
References
[1] Arora N K. ‘Opening up vaccination to younger adults right now will be a gamble with lives. The Times of India April 12, 2021. Available at: https://timesofindia.indiatimes.com/blogs/voices/opening-up-vaccines-for-younger-adults-right-now-will-be-a-gamble-with-lives/ [Accessed 10-05-2021]
[2] Roy I. Re: Will Covid Vaccines Save Lives BMJ 22 March 2021 Available at: https://www.bmj.com/content/371/bmj.m4037/rr-20?fbclid=IwAR0ByBoEbn3e1GuQ3NVf96LYESMlwd-8nJzyykRELDEcndeTTOidDv5nIrE [Accessed 10-05-2021]
[3] CDC. Risk for Covid-19 Infection, Hospitalization and death by Age Group. Updated Feb 18, 2021. Available at: https://www.cdc.gov/coronavirus/2019-ncov/covid-data/investigations-discovery/hospitalization-death-by-age.html[Accessed 10-05-2021]
[4] Banaji M. Covid-19: What the third National Sero-Survey Result Does and Does Not Tell Us. Science. The Wire. Health; February 05, 2021. Available from: https://science.thewire.in/health/third-national-seroprevalence-survey-icmr-covid-19-rural-prevalence-test-positivity/ [Last accessed on 2021 Mar 02]
[5] Havervall S, Falk A J, Klingström J, Ng H, Greilert-Norin N, Gabrielsson L, et al. SARS-CoV-2 induces a durable and antigen specific humoral immunity after asymptomatic to mild COVID-19 infection. medRxiv 2021.01.03.21249162; doi: https://doi.org/10.1101/2021.01.03.21249162
[6] Otmani M. A majority retained protective antibodies 9 months after infection, shows new study. Norid Life Sciences News Februrary 16, 2021. Available from: https://nordiclifescience.org/a-majority-retained-protective-antibodies-9-months-after-infection-shows-new-study/ (accessed 11-05-2021)
[7] Gaebler, C., Wang, Z., Lorenzi, J.C.C. et al. Evolution of antibody immunity to SARS-CoV-2. Nature 591, 639–644 (2021). https://doi.org/10.1038/s41586-021-03207-w
[8] Hanrath A T, Brendan A I P, Duncan C J A, Prior SARS-Cov-2 Infection is associated with protection against symptomatic reinfection. Journal of Infection 2021; 82: 4: E29-E30.
[9] Wajnberg A, Amanat F, Firpo A, Altman D R, Bailey M J, Mansour M, et al. Robust neutralizing antibodies to SARS-Cov-2 infection persists for months. Science 2020; Vol. 370, Issue 6521, pp. 1227-1230. DOI: 10.1126/science.abd7728
[10] Ripperger T, Uhrlaub J L, Watanabe M, Sprissler R, Nikolich-Zugich J, Bhattacharya D, et al. Orthogonal SARS-CoV-2 serological assays enable surveillance of low-prevalence communities and reveal durable humoral immunity. Immunity 2020: 53: 5: P925-933.E4. https://doi.org/10.1016/j.immuni.2020.10.004
[11] Li Z, Liu J, Deng H, Yang X, Wang H, Feng X, et al. SARS-CoV-2-specific T cell memory is long lasting in the majority of convalescent COVID-19 individuals. BioRxiv Preprint. doi: https://doi.org/10.1101/2020.11.15.383463
Suggested Research Areas related to Vaccination
1. Age wise morbidity and mortality since the start of the pandemic should be available in the public domain for researchers.
2. Repeated national level serosurveys in real time at the end of the second wave can map the susceptibility region wise and guide vaccination strategy.
3. Follow up of recovered cohorts long term for re-infection, severity and outcome will also give evidence base on duration of immunity after natural infection.
4. Ongoing research on vaccine effectiveness under field conditions by following cohorts of vaccinated and unvaccinated in different age strata should also be high on priority.
5. Proper investigations of all AEFI.
(The opinions expressed in this article are the author’s own.)
