- World's first confirmed case of COVID-19 reinfection is from Hong Kong
- The strain of virus is different from the one in previous infection: Expert
- COVID patients should not be complacent about prevention measures: Experts
New Delhi: According to a new research to be published in the journal Clinical Infectious Diseases, scientists from the University of Hong Kong have claimed to have the first evidence of reinfection of COVID-19. Thus, confirming that it is possible to get COVID-19 twice, say experts adding that there is no need to be worried as reinfection from coronavirus seems to be rare. The evidence gathered for COVID-19 reinfections has, however, raised questions around how durable our immunity really is against SARS-CoV-2. The Hong Kong University researchers have said that a 33-year-old IT (Information Technology) worker who contracted the coronavirus in March this year and was cleared of Covid-19 and discharged from a hospital in April, tested positive for the virus again after returning from Spain earlier this month. At first, he was suspected to be a “persistent carrier” of the virus from his previous infection but now the researchers have proved it to be reinfection. The findings also show that the viral strain in the reinfection is genetically varied from the virus contracted by him earlier. Two patients in Europe have also been confirmed to have been re-infected with COVID-19. The Health Minister of Telangana has also announced that the day after Hong Kong case came to light, at least two cases of coronavirus reinfection have taken place in the state.
Explaining about the chances of reinfections and what happens during it, Dr Jayaprakash Muliyil, Ex. Principal, CMC Vellore and Leading Epidemiologist said,
What is impressive about this particular finding is that we had expected this to occur more frequently than it is happening now. There are two issues that we must understand- first, a person who is already infected by a virus, very often acquires immunity but may permit the temporary colonisation of his nose, throat or gut. This is a well-known phenomenon. In coronavirus, for some reason, we were not finding it. Now here there is an added spin to it. The researcher of Hong Kong University said that the virus isolated in the reinfection case is genetically different from the virus in the previous infection. It could be a genetic variant but by and large, the probability of that is low. So without more information on this, it will be difficult to predict how it will turn out. What we know as of now is that in this particular case, there no symptoms of coronavirus disease.
He further emphasised that the person who got the reinfection, contracted the virus from somebody and so there is a threat of spreading around of the virus among other people who have come in contact with him. Dr. Muliyil highlighted that reinfections are a rare phenomenon. He said,
The fact that reinfection is rare is a fascinating thing about coronavirus. For example, there is a 24 per cent chance that an adult who is fully vaccinated with poliovirus can establish the virus temporarily if given the poliovirus. But in the case of coronavirus, the human body is not easily permitting reinfections.
According to Dr. Muliyil, there may not be a need for a different vaccine for the modified strain of virus causing reinfections because those viruses may not be too different in genetic sequence from the original virus. However, he highlighted that currently there are only preliminary findings available and with more evidence and information only it will be clear if there is a need to go for another vaccine to avoid reinfections. While talking about the sustainability of the immunity developed by patients who recover from COVID-19, Dr. Muliyil said,
There is a group of experts who believe that the immunity developed while recovering from COVID-19 is pretty solid and may last for quite some time but on the other hand there are also studies that question the strength of the antibodies made and the immunity developed. There have been instances where a fading of antibodies is seen. So there is still not conclusive evidence on antibodies. The variation in the genetic sequence that the researchers of Hong Kong University have talked about in their paper, is a pretty common phenomenon in viruses. There are high chances that these viruses do not require a new antibody or a new vaccine.
Talking about reinfections in the case of coronavirus, Dr Paul Offit an American paediatrician specializing in infectious diseases, vaccines, immunology, and virology also said that reinfections are rare. He said,
The question is does the natural infection protect against reinfections? In other words, are there people out there who got moderately to severely ill from COVID-19 and recovered and got moderately to severely ill again when they encounter this virus again? If that’s true, then it is really worrying but we haven’t really heard that yet.
He further said that there are certain viruses from which the natural infection gives no protection and there are multiple infections, therefore, there are no vaccines developed for such diseases. In case of coronavirus, he said, the virus has been out there for only eight or nine months and the researchers do not have a lot of information about it yet but one can be optimistic based on what the experience has been till now that natural infection does offer some level of protection for some length of time, Dr Offit said.
Earlier, there have been documented cases of patients who tested positive for COVID-19 multiple times, but, according to Dr. KK Agarwal, President, Confederation of Medical Associations in Asia and Oceania (CMAAO) and Medtalks, Heart Care Foundation of India, it was because of the virus’ genetic material- mostly dead or weakened lingers within the body, leading to repeated positive tests. However, the newly documented cases have shown two separate strains of SARS-CoV-2 (the novel coronavirus that causes COVID-19), which show that infections can indeed occur twice. Therefore, the COVID-19 patients should not be complacent about prevention measures thinking that they have enough immunity against the virus, he said.
NDTV – Dettol Banega Swasth India campaign is an extension of the five-year-old Banega Swachh India initiative helmed by Campaign Ambassador Amitabh Bachchan. It aims to spread awareness about critical health issues facing the country. In wake of the current COVID-19 pandemic, the need for WASH (Water, Sanitation and Hygiene) is reaffirmed as handwashing is one of the ways to prevent Coronavirus infection and other diseases. The campaign highlights the importance of nutrition and healthcare for women and children to prevent maternal and child mortality, fight malnutrition, stunting, wasting, anaemia and disease prevention through vaccines. Importance of programmes like Public Distribution System (PDS), Mid-day Meal Scheme, POSHAN Abhiyan and the role of Aganwadis and ASHA workers are also covered. Only a Swachh or clean India where toilets are used and open defecation free (ODF) status achieved as part of the Swachh Bharat Abhiyan launched by Prime Minister Narendra Modi in 2014, can eradicate diseases like diahorrea and become a Swasth or healthy India. The campaign will continue to cover issues like air pollution, waste management, plastic ban, manual scavenging and sanitation workers and menstrual hygiene.