១៨ សីហា ២០២១ / 18 August 2021 – Article in English (*)
ក្នុងអត្ថបទជាភាសាអង់គ្លេស ខាងក្រោមនេះ លោក សម រង្ស៊ី លើកឡើងពីករណីអ្នកដែលបានឆ្លងជំងឺកូវីដ-១៩ ហើយបានជាសះស្បើយ ដោយមិនមានរោគសញ្ញាអ្វីដ៏ធ្ងន់ធ្ងរឡើយ។ អ្នកខ្លះមិនទាំងដឹងខ្លួន ថាខ្លួនបានឈឺផង។ អ្នកទាំងនោះ ទទួលបានភាពស៊ាំដោយធម្មជាតិ (Immunité naturelle) ហើយមិនអាចឈឺម្តងទៀត ពីជំងឺដដែលនេះទេ។ សូមរំលឹកថា ករណីបែបនេះ មានចំពោះមនុស្ស ៩៨ ភាគរយ ដែលបានឆ្លងជំងឺកូវីដ-១៩ មានន័យថា មានតែ ២ ភាគរយទេ នៃអ្នកជំងឺកូវីដ-១៩ ដែលមានអាការៈធ្ងន់ធ្ងរ រហូតដល់ទទួលមរណភាព។
អ្នកដែលទទួលបានភាពស៊ាំដោយធម្មជាតិបែបនេះ មានចំនួនកាន់តែច្រើនឡើងៗ ដែលជាហេតុធ្វើឲ្យការរាតត្បាតជំងឺកូវីដ-១៩ អន់ថយជាបណ្តើរៗ ដោយខ្លួនឯង។ ការចាក់វ៉ាក់សាំង ក៏មានគោលបំណងផ្តល់ភាពស៊ាំដែរ ហើយភាពស៊ាំតាមរយៈវ៉ាក់សាំង (Immunité vaccinale) បូកបញ្ចូលជាមួយភាពស៊ាំដោយធម្មជាតិ (Immunité naturelle) ធ្វើឲ្យប្រជាពលរដ្ឋកាន់តែច្រើនឡើង មានភាពស៊ាំដូចគ្នា ដើម្បីការពារខ្លួន ពីមេរោគជំងឺកូវីដ-១៩។ នៅពេលដែលប្រជាពលរដ្ឋដ៏ច្រើនលើសលប់ (ចាប់ពី ៨០ ភាគរយឡើងទៅ) ទទួលបានភាពស៊ាំ ដោយធម្មជាតិក្តី តាមរយៈវ៉ាក់សាំងក្តី ពេលនោះ ប្រជាពលរដ្ឋទាំងមូលនឹងមានអ្វីដែលគេហៅថា ភាពស៊ាំជាសមូហភាព ឬ ភាពស៊ាំរួម (Immunité collective) ដែលជាដំណាក់កាលចុងក្រោយ ដើម្បីបញ្ចប់ការរាតត្បាតជំងឺនេះ។
នៅប្រទេសឥណ្ឌា ប្រជាពលរដ្ឋ ៦៧ ភាគរយហើយ បានទទួលភាពស៊ាំ ភាគច្រើនដោយធម្មជាតិ ហើយមួយភាគទៀត តាមរយៈការចាក់វ៉ាក់សាំង។ អញ្ចឹងហើយ បានជាគេកត់សម្គាល់ថា ក្នុងរយៈពេលប៉ុន្មានខែចុងក្រោយនេះ ចំនួនអ្នកឈឺ និងអ្នកស្លាប់ ដោយជំងឺកូវីដ-១៩ នៅប្រទេសឥណ្ឌា មានការធ្លាក់ចុះយ៉ាងខ្លាំង។
(*) COVID-19 Vaccine Programmes Need Review as Natural Immunity Grows
This article refers mainly to the health situation in France but its arguments apply also to the whole of the European Union, which has defined the steps for a COVID-19 “health pass” applicable to the 27 member states.
Millions of people continue to oppose mass vaccination against COVID-19 and the generalised use of the health pass in its current form. They are right on at least one point. There are millions of people who do not need to be vaccinated for the simple reason that they are immune, having already contracted COVID-19, most often without even realising it.
Millions of recoveries
The vast majority of people having been contaminated with COVID-19 were “ill” despite being more or less asymptomatic and recovering more or less spontaneously.
Millions of people fall into this category but are being indiscriminately pushed by the authorities to get vaccinated. The alternative is severe restrictions on their rights and liberties.
A special status for the recovered
In April I founded the Association de défense des droits et libertés des anciens malades de la COVID-19 (1), or the Association for the Defense of the Rights and Liberties of COVID-19 Recoveries, to demand the recognition of a specific immunological status for these people. This would have a number of practical consequences.
The French health pass created on July 1 on the European model does recognise this special status as recovered people can get the document without being vaccinated. In the absence of a certificate of vaccination, the health pass depends on a “certificate of recovery.” This proof of recovery can be simply a polymerase chain reaction (PCR) test showing infection by the coronavirus within the last six months for at least 11 days.
Encouragement from recoveries
Each wave of the pandemic leads to a terrifying surge of hospitalisations and deaths. But the waves also bring a considerable increase in the number of people who have recovered. We hear much less about these people, but they should be a source of reassurance for society. These people have acquired a natural immunity which protects them from new infection and limits their infectiousness.
Proof of this immunity is the presence of antibodies in the blood, which can be checked for recovered people as for the vaccinated. The process of natural immunity goes beyond the production of antibodies (humoral immunity) and also includes the intervention of T lymphocytes, or “killer cells” (cellular immunity).
In the face of virus mutations, these T lymphocyte cells are a precious weapon of defence provided by natural immunity. Antibodies only recognise the proteins on the surface of the virus. These proteins are the most likely to mutate, leaving the antibodies ineffective. But some T lymphocyte cells are capable of recognizing the internal virus proteins, which are the least likely to mutate. These T lymphocyte cells can continue to destroy infected cells despite superficial mutations in the virus.
Natural and Vaccine Immunity
The most recent studies show that natural immunity lasts for at least a year, with the probability that it will last much longer. This will be confirmed as time passes. Read, for example, “Had COVID? You’ll probably make antibodies for a lifetime.” (2)
Natural immunity at least matches vaccine immunity on the criteria of efficiency, durability and adaptability to variants. Vaccines are simply pieces of engineering designed to create a replica of natural immunity. There is no reason to think that the copy can be better than the original.
The French authority the Haute Autorité de Santé (HAS) recognizes the immunity of those who have recovered by recommending that they have only a single vaccination shot. This effectively equates in an arbitrary way natural immunity with the immunity resulting from a single injection. But recovered people may very well not need to be vaccinated, even with a single dose. This dose recommended by the HAS is simply a precaution which may not be really indispensable, as the study cited above shows.
The role of the recovered in collective or herd immunity
Those who have recovered from COVID-19 and have natural immunity are much more numerous than often thought. According to the last serological study seeking antibodies carried out by Institut Pasteur in April 2021, “Proportion de la population ayant été infectée par Sars-Cov-2“ (3), there were then more than 9 million such people in France.
By comparison, in India around the end of July, 67% of the total population was immunised as proved by antibodies, while only 25% of the adult population had received a first vaccine injection and only 7% had received two doses. India is therefore approaching the threshold of collective or herd immunity (4), which will be achieved more through the natural route than through vaccines.
Through the herd immunity which is being achieved in India, the epidemic is rapidly retreating in the country. This is shown by the sharp decline in the daily numbers of new cases and deaths in recent months.
Abuse of tests for the health pass
To get the health pass without being vaccinated, numerous people, including some who have had COVID-19 and recovered, have been undergoing repeated PCR or antigenic tests. The results of these virological tests must be negative to get the health pass, but they are only valid for 72 hours. The repetition of these “comfort” tests can become an abuse and represents a cost to society. It becomes an aberration when it includes people who have recovered and have immunity, proved by antibodies, which is likely to last for years.
The following steps are needed to reinforce the global fight against COVID-19:
– continue with studies to compare natural and vaccine immunity and measure the differences in terms of efficiency, durability and adaptability to variants;
– identify through periodic serological investigations the populations who don’t yet have immunity and distinguish them from those who do, whether through vaccination or infection;
– avoid wasting PCR or antigenic “comfort” tests on people who have recovered;
– re-examine the policy of wholesale vaccination by taking account of those who have recovered and transferring the vaccine doses made available to poor countries which have much worse shortages of vaccines; and
– establish in the poor countries which are generally very heavily populated an order of priority for vaccination, by identifying – through tests carried out since the start of the pandemic – those who have recovered and have the least need to be immediately vaccinated.