What do we know about immunity with COVID -19?
After four months of pandemic, there is still no definitive data on its formation and its extent. But the reinfection is no longer going
The World Health Organization has warned that countries that relax quarantine restrictions may face a new outbreak of coronavirus because they are not properly prepared for it. This message came at a time when France and Belgium decided to ease quarantine restrictions, resume schooling in the Netherlands and the United Kingdom presented plans to revive the economy. WHO warns that without constantly testing and monitoring the contacts of sick people, quarantined countries could face a new wave of powerful diseases. Meanwhile, medical and scientific circles have still not reached definitive conclusions on one of the most important questions – is immunity developing in those who have had COVID-19 before? Although more and more specialists are inclined to the idea that immunity nevertheless forms. The question is how strong each person can be. What is known at the moment about the development of immunity and repeated cases of infection – discovered Ukrinform.
Only 7-8% of infected people may not receive immunity at all
In late April, the World Health Organization made an encouraging statement that the patient’s recovery from COVID-19 does not protect him from re-infection and there is no evidence of mandatory development of patient immunity. “WHO claims that to date there is no evidence that people who have recovered from COVID-19 and who have antibodies are protected from reinfection,” said the report. Therefore, experts from an international organization have warned countries against the introduction of a so-called “immune passport” (any evidence that a person has been sick and has antibodies to the virus. – Author ), because its owners will consider themselves protected and will not adhere to social distance.
The US Center for Disease Control and Prevention (CDC) website also states that “the immune response, including the duration of immunity to SARS-CoV-2 infection, has not yet been studied. “It is unlikely that patients with MERS-CoV (Middle East Coronavirus Respiratory Syndrome who broke out in 2012-2013 and camels) will be re-infected soon after recovery, but it is not yet known if any Similar immune defenses will be seen in patients with COVID-19. “
However, Ancha Baranova, doctor of biological sciences, professor at the School of Systems Biology at George Mason University (United States), made a more specific statement based on data from Chinese scientists who examined 171 patients in Shanghai Medical Center, as well as a number of other scientific institutions.
She noted that only 7 to 8% of people with a disease acquire strong and lasting immunity to the coronavirus. “There are super people who have such a strong immune response that their antibodies can be used to treat other people with plasma, which is done,” said Baranova. She added that such immunity is formed more often in people with severe course of the disease.
At the same time, she said, there are those who have all the symptoms of the disease, but they generally do not have antibodies to the virus. There are also around 7 to 8%. According to Baranova, this means that the interferons (complex proteins with antivirals, anti-blastomas, antitumors, immunostimulants and other types of activity – ND) in the body have coped with the infection. Everyone else who has been sick with COVID-19 has variable strength immunity, and in 40% of them it is quite weak.
What opinion do Ukrainians have?
Famous immunologist, assistant professor of pediatric infectious diseases and pediatric immunology NMAPE named after P.L. Shupika Fedor Lapiy thinks that today there is no reason to claim that immunity is not formed. He spoke about it in an interview with Ukrinform, answering the question of the formation of collective immunity. “These observations, which were made on both the first SARS and SARS-CoV-2, suggest that the immune response exists. But now there is little time left to draw conclusions regarding SARS-CoV-2 and its subsequent mutations. However, the existing data on viral mutations do not allow us to speak of short-term immunity. Immunity is formed, “said Fedor Lapiy.
Immunologist Andrei Volyansky on his Facebook page also noted that with previous versions, immunity to human coronaviruses persisted for 2-3 years.
However, reinfection of COVID-19 is practically impossible.
From the start of a pandemic, information about repeated cases of coronavirus infection appears periodically. One of the first such reports came back in late February, when 195 cases of repeated infections in Wuhan were reported. Later in China, it was clarified that after following these patients, doctors found no signs of spreading coronavirus – that is, they no longer infected others. But this is precisely what has given rise to much concern, and whether immunity can really be gained by overcoming COVID-19.
Experienced immunologists question the accuracy of the studies, rather than the unusual nature of the infection. “There have been reports of reinfection, but they are criticized for revealing certain methodological errors in the organization of the research. Therefore, there are some doubts about the reliability of this data, “said Fedor Lapiy.
There have also been reports of suspected reinfection in Ukraine – on April 20, four patients were discussed in the Rivne region. But, as if to confirm Mr. Lapiya’s remarks, the following day, the vice-president of the regional administration of Rivne, Igor Tymoshenko, denied this information. “It is not a reinfection. These are patients who have almost recovered. All, without exception, pass the PLR tests. The test showed that they still have a coronavirus, which may indicate that the virus can stay in the human body for more than 14 days, “said Igor Tymoshenko.
And the other day, specialists from the Center for Disease Control and Prevention in South Korea seem to have marked the “i” in this case. They said that analyzes of individuals who, after recovering from COVID-19, again show the coronavirus, are false positive, reports the “correspondent” with reference to Reuters. In other words, the test results are caused by particles of SARS-CoV-2 remaining in the body. In addition, representatives of the Center consider that these patients are not contagious. According to a vaccine development expert from the University of Seoul – Seoul Dai-wu, in some cases, tests can detect old fractions of coronavirus. South Korean doctors use reverse transcription polymerase chain reaction (RT-PCR) tests to determine the genetic material of the coronavirus – this diagnostic method is considered the most accurate.
Why is there still no definitive and concrete answer to these most important questions? This is explained by the novelty of the virus and the lack of extensive research. The Air Force, for example, writes that none of the people have been specially infected again to check if they are immune. But such a test passed a pair of experimental rhesus monkeys. “They were infected twice: first, to provoke an immune response, and after three weeks – again. And although the experience was very limited, neither of the two monkeys after reinfection with such a short interval showed symptoms of the disease, ”the document said.
Pangolins have survived millions of years of evolution without virus protection
Well, it is worth understanding that it takes time to study these problems specifically. For example, it was only recently that scientists discovered that scaly pangolins, by which interspecies transmission of the virus likely occurred, do not form an immune response to the virus (due to the absence of sensitive genes virus), and they can probably deal with viruses through some other mechanism, “New time” reported. “Our work shows that lizards have survived millions of years of evolution without the antivirus protection used by all other mammals (humans, cats, dogs and others). Other studies on dinosaurs will show how they manage to survive with viral infections, and this can help develop new treatment strategies for people with viral infections, “says co-author Dr Leopold Eckhart of the Medical University of Vienna in Austria.
Meanwhile, in a context of lack of research, some try to steal the achievements of their colleagues. The New York Times reports that the FBI, in conjunction with the United States National Security Agency, will issue a warning to China about hacker attempts to steal data regarding the development of a vaccine against COVID-19 – university and private laboratories. In addition to China, Iran, Vietnam and South Korea are trying to cyber attack American research centers, the newspaper noted.
Julia Gorban, Kiev
According to the materials: ukrinform.ru