Survey confirms it is possible to catch COVID twice

August 24, 2020-Hong Kong researchers say they have confirmed that a person can be infected twice with COVID-19.

Social media sites have sporadic accounts of those who say they have got their COVID twice. But scientists are skeptical of the possibility and say there is no evidence of that happening.

New evidence comes from a 33-year-old man in Hong Kong who first caught COVID-19 in March. He was tested for Coronavirus After he developed cough, sore throat, heat, And headache for 3 days. He stayed in the hospital in mid-April until he was tested negative for the virus twice.

On August 15, the man returned to Hong Kong from a recent trip to Spain and England. There has been a recent recurrence of COVID-19 cases in the region. At the airport, they were screened for COVID-19 using a test to check their saliva for viruses. He had a positive reaction, but this time he had no symptoms. He was taken to the hospital for surveillance. His viral load-the amount of virus in his body-decreases over time and his Immune system I was handling the intrusion myself.

What is special about his case is that every time he was hospitalized, the doctor sequenced the genome of the virus that infected him. It varies slightly from infection to infection, suggesting that the virus has been mutated or changed in the four months following infection. It also demonstrates that the coronavirus can infect the same person twice.

World Health Organization experts responded to the incident at a news briefing on Monday.

“What we are learning about infections is that people develop an immune response,” said Maria Van Kerkhove, an epidemiology infectious disease epidemiologist at the World Health Organization in Geneva, Switzerland.

A study on male cases is prepared for publication in the journal Clinical infection.. Experts say this finding should not alert, but it has a significant impact on the development of Herd immunity Effort to come up with vaccine And treatment.

“We are happy to announce that Veterinary Medicine is the best choice for vaccines and immunology.” “The big unknown is how often this happens,” he says. Further investigation is needed to find out if this was a rare case or a frequent occurrence.

There is a past experience guide

Poland says there is no need to worry if COVID-19 could be obtained twice.

This also happens with other types of coronavirus-common cold.. These coronaviruses change slightly each year as they orbit the earth. This causes the coronavirus to continue to spread, causing a common type of misery.

It also occurs with seasonal flu. That’s why people have to be vaccinated against the flu every year, and why flu vaccines have to be changed little by little each year to keep up with the ever-evolving flu virus.

“We have continued to make Influenza vaccine 80 years, and Clinical trial It happens when we’re talking to find new and better flu vaccines,” says Poland.

was there Other evidence The virus that causes COVID-19 also changes in this way. Researchers at the Howard Hughes Medical Center at Rockefeller University in New York recently used a major portion of the SARS-CoV-2 virus, a genetic directive for spike proteins, to repeatedly infect human cells. Scientists watched as each new generation of the virus was born to infect a new batch of cells. Over time, some copies were genetically modified because they copied themselves, allowing them to survive even after scientists attacked them with neutralizing antibodies. These antibodies are one of the primary weapons used by the immune system to recognize and neutralize viruses.

Although this study is still a preprint and has not yet been reviewed by outside experts, the authors note that the virus may change in ways that help evade our immune system. I wrote that I discovered. True, they wrote in mid-July, which means that people who have a weak immune response to the virus when they first encounter it, especially reinfection, are possible.

Good news

The same is true for men from Hong Kong. When the doctor examined his blood for antibodies to the virus, he found nothing. It may mean that he initially had a weak immune response to the virus, or the antibodies he made during his initial infection diminished over time. But during the second infection, he soon developed more antibodies. This suggests that the second infection acted like a booster for boosting immunity. This is probably why he never showed symptoms again.

That’s good news, Poland says. That means our body can get better at fighting off the COVID-19 virus, and catching it once means the second time may not be so bad.

However, the fact that viruses can change rapidly in this way has some impact on the effort to come up with a successful vaccine.

“I think the potential implication of this is that you have to give booster doses. How often is the problem,” says Poland. It depends on how fast the virus changes and how often reinfections occur in the real world.

“I was a little surprised at the four and a half months,” said the Polish, referring to the time it took for Hong Kong people to become infected. “I’m not surprised, I got infected last winter, and I got infected again this winter,” he says.

It also has immune-based therapies such as convalescence plasma And Monoclonal antibody The virus may have been altered in ways that help outperform these treatments, so it may have limited usefulness over time.

Convalescent plasma is a concentrated dose of antibodies from people who have recovered from a COVID-19 infection. As the virus changes, its plasma antibodies may not work well for future infections.

Pharmaceutical companies have learned to harness the power of monoclonal antibodies as a powerful treatment for cancer and other diseases. Mass-produced monoclonal antibodies in the lab mimic the body’s natural defenses against pathogens. Just as the virus becomes resistant to innate immunity, it can change in a way that is better than the cure created in the laboratory. Some pharmaceutical companies developing monoclonal antibodies to fight COVID-19 have created a cocktail of antibodies designed to neutralize the virus by fixing it at various locations, creating We are already prepared for the possibility.

“There is a lot to learn,” says Poland. “Now that the proof of principle has been established, this man also needs to be more aggressively researched to define how often this occurs, given his knowledge of seasonal coronaviruses.”