As the world awaits the arrival of a safe and effective coronavirus vaccine, a team of researchers have come forward with a provocative new theory: that the mask can help severely immunize some people against the virus.
The unproven idea, described in a commentary published Tuesday in the New England Journal of Medicine, is inspired by the old-fashioned concept of variability, from the deliberate exposure of a pathogen to produce a protective immune response. At first tried against smallpox, the risky practice eventually fell out of favor, but paved the way for the rise of modern vaccines.
Masked exposures are no substitute for a sonar. But data from coronovirus-infected animals, as well as glowing insights from other diseases, suggest that masks can reduce the likelihood of becoming ill, by cutting the number of viruses a person encounters through the airway. And if a small number of pathogens still slip through, the researchers argue, these can induce the body to produce immune cells that can miss the virus and surround it to fight back again Can stick.
“You may have this virus, but may be asymptomatic,” said Dr., an infectious disease physician at the University of California, San Francisco. Monica is one of the authors of Gandhi and commentary. “So if you can drive rates of asymptomatic infection with masks, maybe it’s a way to isolate the population.”
This does not mean that people should intentionally donate a mask to vaccinate themselves with the virus. “It is not a recommendation at all,” Dr. Gandhi said. “Neither are pox parties,” he said, referring to social ceremonies that affect healthy and sick people.
The theory cannot be directly proved without clinical trials comparing the results of those with those in the presence of coronovirus to those that are unmasked – an inelastic experimental setup. And while outside experts were intrigued by the theory, they were reluctant to embrace it without much data, and advised careful interpretation.
“It feels like a leap,” Saskia Popescu, an infectious disease epidemiologist based in Arizona, did not include in the comment. “We don’t have much to support it.”
Taken incorrectly, this idea may create a sense of falsehood with decency, possibly putting them at greater risk than before, or perhaps even raising the misconception that face covering is completely useless against coronovirus , Because they cannot present to the wearer. Impermeable to infection.
“We still want people to follow all other prevention strategies,” Drs. Popesu said. This means being alert to crowd avoidance, physical disturbances and hand hygiene – behaviors that overlap in their effects, but cannot replace each other.
The coronovirus variogram theory rests on two assumptions, which are difficult to prove: low doses of the virus cause severe illness, and this mild or asymptomatic infection may induce long-term protection against subsequent bouts of the disease. Although other pathogens have offered some precedents for both concepts, the evidence for coronovirus is scant, as scientists have only had the opportunity to study the virus for a few months.
Experiments in the hamster have hinted at the association between dose and disease. Earlier this year, a team of researchers in China found that hamsters behind a barrier made of surgical masks were less likely to be infected with coronaviruses. And those who contracted the virus became less ill than other animals without masks to protect them.
Some observations in humans support this trend. In crowded settings where there is widespread use of masks, the rate of infection decreases. And although face coverings may not block all inbound virus particles for all people, they appear to be associated with less disease. Researchers have found largely silent, disease-prone outbreaks ranging from cruise ships to food processing plants, mostly all masked people.
Data linking symptoms to doses have been gathered for other microbes that attack the human airway, including influenza viruses and bacteria that cause tuberculosis.
Frequently Asked Questions
Updated September 4, 2020
What are the symptoms of coronavirus?
- In the beginning, the coronovirus looked like it was primarily a respiratory disease – many patients had fever and chills, were weak and tired, and had a lot of coughing, although some people do not show many symptoms at all. Those who were most ill had pneumonia or acute respiratory distress syndrome and received supplemental oxygen. So far, doctors have identified many more symptoms and syndromes. In April, the CDC added to its list of early signs of sore throat, fever, chills and muscle aches. Gastrointestinal upset, such as diarrhea and nausea have also been observed. Another telltale sign of infection can be a sudden, profound deterioration of the sense of smell and taste. In some cases teenagers and young adults have developed painful red and purple lesions on their fingers and toes – “kovid toes” – but some other serious symptoms.
Why is it safe to spend time outside?
- There is less risk in outdoor ceremonies because the air spreads viral droplets, and sunlight can kill some viruses. Open spaces prevent the virus from forming in a concentrated amount and inhale, which can occur when infected people breathe in a confined space for a long period of time, a virologist at the University of Leicester, Dr. Julian W. Tang said.
Why does standing six feet away from others help?
- Coronovirus spreads primarily through drops from your mouth and nose, especially when you cough or sneeze. The CDC, one of the organizations using that measure, bases its recommendation of six feet on the idea that the largest drops that people eject will fall to the ground within six feet when they cough or sneeze. But six feet has never been a magic number that guarantees complete safety. Sneezing, for example, can launch a lot more drops than six feet, according to a recent study. This is a rule of thumb: You should stand outside the safest six feet, especially when it is windy. But keep a mask at all times, when you feel you are very different.
I have antibodies. Am i immune now?
- Right now, at least for several months, it seems. There are horrifying accounts of the suffering people that lead to the second battle of Kovid-19. But experts say these patients may have a draw-out course of infection, in which the virus moves slowly for months after its initial exposure. People infected with coronaviruses usually produce molecules called antibodies, which are protective proteins formed in response to an infection. These antibodies can only remain in the body for two to three months, which may seem worrying, but it is completely normal after an acute infection, Dr. Said Michael Mina, an immunologist at Harvard University. It may be possible to regain coronavirus, but it is much less likely that the initial infection will be possible in a shorter window of time or make people sick for a second time.
What are my rights if I worry about going back to work?
But despite decades of research, the mechanics of airborne transmission remain largely “a black box”, said Jyoti Rengrajan, an expert in vaccines and infectious disease at Emory University who was not involved in the remarks.
This is partly because it is difficult to reduce the infectious dose required for a person to drown, Drs. Rengarajan said. Even if researchers eventually settle on an average dose, the results will vary from person to person, as factors such as genetics, a person’s immune status, and the architecture of their nasal passages can all affect How much the virus can colonize the respiratory tract.
And confirming the second half of the theory of violations – that masks allow entry into the virus just enough to prime the immune system – can be very difficult. Although several recent studies have pointed to the possibility that mild cases of covid-19 may provoke a strong immune response to coronovirus, durable protection may not be proven until researchers resolve them months later Or do not collect data on infection for years.
Overall, the theory “has some properties”, said Angela Rasmussen, a virologist at Columbia University, who was not included in the comment. “But I’m still very confused.”
It is important to remember, she said, that vaccines are inherently less dangerous than actual infections, which is why practices such as variolation (sometimes called inoculation) eventually become outdated. Prior to the discovery of vaccines, doctors created smallpox stains or pieces of pus by rubbing into the skin of healthy people. The resulting infections were generally less severe than the cases of smallpox, but “people certainly succumbed to smallpox and died of variolation,” Dr. Rasmussen said. And vaccination, unlike vaccines, can make people contagious to others.
Dr. Gandhi accepted these limitations, noting that the principle should be considered nothing more than this – a theory. Still, he said, “When we are waiting for the vaccine, why not increase the chances of getting sick and not having some immunity?”