What We Know (and Don’t Know) About Asymptomatic COVID-19

Medical professionals investigating the potential major role of asymptomatic carriers in the development of COVID-19 since the outbreak of a pandemic. It was one of the big mysteries about Coronavirus, Because it is not thoroughly followed up with other respiratory disorders.

Evidence suggests that nearly half of all cases of COVID-19 may be asymptomatic. In addition, people who are completely asymptomatic, especially children, can spread it as easily as people who are infected. This highlights the need to track, examine, and isolate all individuals who are exposed to disease early and often.

Nevertheless, the Centers for Disease Control and Prevention Test guidelines Early this week, Those who do not have the symptoms of COVID-19 say they do not need to be tested, even if they are exposed to a sick person. CDC director later Revealed That those individuals may be “considered” for testing.

Health experts say that if you don’t even know who has COVID-19, it’s very difficult to handle COVID-19. Even asymptomatic people can have a significant impact on the future of a pandemic.

Many of the questions about asymptomatic infections remain open, but scientists have gathered a lot of new insights over the past two months, providing a clearer picture of those who have never developed symptoms. Helped to figure out.

Below are some of the things we currently know about asymptomatic carriers.

Ah Research came out in June It shows that about 40% of infected people tested for COVID-19 in a small Italian town were asymptomatic. In Boston, Clinicians tested a group of people who were homeless And It turned out that all 146 people who lived in the inn and were judged positive had no symptoms.

further, Contract tracking efforts In Washington DC, it was recently revealed that about half of patients diagnosed with COVID-19 were not in contact with those who were diagnosed, suggesting that most are likely to get sick without other symptoms. Suggests.

CDC guidance is currently available here for the largest number of asymptomatic individuals in the United States. 40% Of the case.

However, while it is clear that there are many asymptomatic cases, it is not clear how prevalent doctors are.

“We“I still don’t really know how many people will be asymptomatic from this disease.” Manisha Jutani, Yale Medical Infectious Diseases Specialist.

Scientists can estimate numbers through research, but these statistics capture little reality of the population as a whole.

Data from the beginning of the pandemic suggested that asymptomatic cases distorted young and mostly involved people 20s, 30s, 40s..

Children also seem to play a much larger role With a quieter spread of COVID-19 than originally thought. According to researchers, the main reason for this is Children usually do not experience serious symptoms COVID-19; they tend to be asymptomatic or mild, go unnoticed or ignored. This can allow infected people to subconsciously spread the infection.

Recent data has shown that many older people are asymptomatic. 1 Research published in JAMA In mid-August, 88% of older adults who were positive for COVID-19 in a Connecticut nursing home were found to be asymptomatic. so Chicago Nursing Home, 37% of older people who test positive for COVID-19 have no symptoms.

Ah Recent research Asymptomatic and symptomatic people have similar viral loads in the body, according to a South Korean study. This is the amount of virus present in a person’s throat and nose.

This shows that asymptomatic people can spread the coronavirus (keyword: potentially) as easily as those with symptoms.

But scientists aren’t entirely certain that they are. Alternatively, the viral material found in asymptomatic carriers may not be infectious — according to Juthani, it may be a fragment of dead virus that has not yet been removed from the body.

Coughing and sneezing are believed to be the main causes of coronavirus particles going out and infecting new people. Theoretically, if an infected person has symptoms, they are more likely to cough and sneeze, and more respiratory droplets are likely to be expelled into the environment.

“This allows the viral particles to spread more than in asymptomatic patients,” said Jutani.

Other experts have said that speaking can also very easily infect the virus. “A cough can emit a larger, more cloud of droplets, but we know that just speaking can produce thousands of droplets.” Benjamin Neumann, Virologist and Texas A & M University-Head of the Biology Department of Texarkana.

I am also concerned about the fact that asymptomatic carriers may not take the same precautions as those who are clearly ill (being at home, wearing a mask, etc.).

One theory supported by Research conducted by the Mayo ClinicIt suggests that childhood vaccination, such as pneumonia and polio vaccine, may enhance the immune system’s ability to knock out COVID-19 before symptoms appear.

Another belief is that people Degree of immunity I had been infected with a coronavirus before. There are at least four other coronaviruses that cause a common cold, and our body easily forgets about them.

“This memory seems to provide some protection for the new coronavirus,” Jutani said.

Even if a person infected with coronavirus has no obvious symptoms, Long-term heart failure And internal inflammation of certain individuals. The underlying inflammation can later Cause complications Things like arrhythmias, heart failure, cardiac arrest. College football player who contracted for COVID-19 And developed heart problems.

According to Neumann, previous research on infected animals suggests that even in the absence of symptoms of the disease, there is cell damage later identified in the biopsy.

“In other words, it makes more sense to think of people with mild symptoms that may be hard to notice, but who aren’t really asymptomatic,” Neumann said.

Many health professionals say they need to track and isolate asymptomatic infected individuals.e cannot focus solely on the testing and isolation of sick people.

“Public policy decisions that recommend lower precautions to people who appear to be less vulnerable will result in more spread, rather than the spread of COVID-19,” Neuman said.

Asymptomatic spreads are probably happening all around us. Jutani said the importance of wearing a mask continues, as it can’t be tested or isolated without symptoms.

“Asymptomatic people may not spread the virus as easily as those with symptoms, but they can “pass the baton” to the next person, “said Jutani. As long as you have an asymptomatic infection, “The “virus relay race” can continue.

Experts are still learning about COVID-19. The information in this story is known or available at the time of publication, but guidance may change as scientists discover more about the virus. Please Check Centers for Disease Control and Prevention Latest recommendations.