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The latest: Pfizer vaccine prevents those who have recovered from Covid from getting another attack
MBBS (Cey), DCH (Cey), DCH(Eng), MD (Paed), MRCP (UK), FRCP (Edin), FRCP(Lon), FRCPCH (UK), FSLCPaed, FCCP, Hony. FRCPCH (UK), Hony. FCGP (SL)
Specialist Consultant Paediatrician and Honorary Senior Fellow, Postgraduate Institute of Medicine, University of Colombo, Sri Lanka. Joint Editor, Sri Lanka Journal of Child Health Section Editor, Ceylon Medical Journal
It is now quite well-known that the COVID-19 vaccines very definitely prevent one from getting a severe form of the disease and dying from it. The immunity against severe disease from the SARS-CoV-2 virus is quite high when the recommended doses of vaccines against COVID-19 are properly given and especially so when a Pfizer vaccine booster third dose is given. As the immunity tends to wane a bit after the routine course of two doses is initially given, it has to be stimulated and enhanced by a booster third dose, given at the appropriate interval of time.
To reiterate a very important quality of the COVID vaccines, it must be remembered that the vaccines, in fact, none of the currently available COVID vaccines, can prevent one from contracting the virus and getting the COVID-19 disease to a clinically significant extent. This is a very significant fundamental difference between the COVID vaccines and virtually all other vaccines available against infectious diseases. There are some reports of variable amounts of some protection against one actually getting the COVID-19 disease by some of the vaccines but this has so far not been proven to be one hundred percent protection.
The current thinking is that even the fully vaccinated persons can still contract the virus, albeit escape severe disease and death in the majority, but clearly remain as a source of infection to others. This is the vital rationale behind the often-repeated health advice to even fully vaccinated people to avoid crowds, keep their social distance, wear an effective mask and continue proper washing of hands as the vaccines do not guarantee that one will not get the infection and also prevent one from being a source of spread for the disease. This is of course ever so important in the face of the latest Omicron variant that has a hitherto unprecedented ability to spread like a wildfire.
Yet for all that, it is known that the risk of reinfection with the COVID-19 decreases substantially among patients who have recovered fromthe actual coronavirus disease COVID-19. Research studies have shown that infection with COVID-19 prompts a worthy immune response in the vast majority and provides protection against recurrent infection. What is not known is for how long such valuable protective immunity lasts.
Current worldwide guidelines from all over the planet advocate vaccination of recovered patients even though robust data regarding vaccine efficacy in such situations is still quite limited. Early evidence has shown the effectiveness of Covid-19 vaccination in small groups of recovered patients in the short term. However, the effectiveness in large populations and for extended periods remains quite uncertain. To complicate matters further, how well immunity provided by one strain of the virus will work against another strain is also largely unknown. We just do not have a comprehensive picture of the clinical profile of people who have recovered from COVID-19.
In such a background, a report from Israel, published in The New England Journal of Medicine on 16th February 2022, should be of interest to all of us. Using electronic medical data, the researchers looked at the reinfection rates among patients three months earlier and subsequently received the Pfizer vaccine and those who had not received a vaccine between March 1 and November 26, 2021.
The investigators concluded that administration of the Pfizer vaccine to patients who had recovered from COVID-19 was linked to significantly lower rates of reinfection with the virus. They further stated that their results are compatible with data from other research endeavours that have shown sturdy immunological responses to vaccination in previously infected persons. It is the results of an epidemiological study that corroborates the immunological evidence.
This latest information fits in quite well with the strategies used by the Ministry of Health and the government of Sri Lanka to vaccinate with the Pfizer vaccine even people who have recovered from COVID-19. The way the disease has been spreading in the recent past, the base cohort of people who have had and recovered from COVID must be quite substantial. If by vaccinating such a considerable proportion of our people with a booster dose, we can reduce or prevent them from getting reinfected, the residual pool of people who can spread the disease in the future will be markedly reduced. This would appear to be a “win-win situation” in our fight against the virus.
So, the take-home message is very clear. It is based on currently available scientific evidence. Our health authorities and the government have gone to great lengths and spent a fortune in securing adequate amounts of the Pfizer vaccine for booster doses. They have been shouting from the rooftops and even vehemently pleading with our people to get the booster dose of the vaccine. Yet, for all that, mainly due to misinformation and disinformation, the response from our populace has been quite tardy and unsatisfactory, to say the least.
This article is a plea on the part of the writer, using all available data from scientific studies, for our people to go ahead and take the booster dose of the Pfizer vaccine without any further delay. Just ignore all the false information that is doled out, particularly by social media.
By getting the booster dose of the Pfizer vaccine, you will be contributing your mite to the welfare of our populace in particular and the efforts of our country as a whole in general, to fight this menace of the blot of COVID-19.