New research shows that the new strain of SARS-CoV-2 virus remains deep in the lung tissue of people who have recovered from COVID-19.
A recent Chinese study found that traditional SARS-CoV-2 viruses cannot be detected because they are located deep in the lungs of patients who have recovered from COVID-19, according to the South China Morning Post.
The findings, published in China’s journal Cell Research on April 28, partly explain why there was an increase in patients who were again positive for COVID-19 after they recovered.
Dr Bian Xiuwu, who led the research team from Chongqing Military Medical University (China), said: “Our work provided the first pathological evidence of the surviving SARS-CoV-2 virus. in a patient’s lungs was discharged with three negative results “.
The virus is deep and does not cause symptoms
According to the South China Morning Post, this study is based on the examination of a 78-year-old woman who died from COVID-19.
On January 27, the old lady was taken to Tam Hiep Central Hospital in Chongqing City. She was positive for COVID-19 and later developed symptoms of the disease.
On February 13, she was discharged from the hospital after receiving treatment and three were negative for COVID-19. The sample for COVID-19 test was taken from her nose and throat. However, one day later, the old lady suffered a heart attack and died.
Doctors observe the lungs of COVID-19-infected patients in February 2020 in Wuhan City, Hubei Province (China).
Through the above case, Dr. Bian and colleagues concluded in the study that: “It is necessary to quickly understand the pathogenesis mechanism in COVID-19 patients. Health authorities have not yet determined how the virus has affected. the body has recovered from COVID-19 “.
After autopsy, the COVID-19 was not found in the lady’s liver, heart, intestines, skin or bone marrow.
However, they discovered an entirely new strain of virus in the deep tissue of her lungs. Observing on a microscope, they found the virus still exists in a crown-like coating.
These new hidden strains do not cause any noticeable symptoms. Therefore, mass testing methods that are not available from the lungs will not be visible.
Dr. Bian’s team suggested that a careful review of the patient’s lungs was required before they were discharged from the hospital to find the remaining strains.
To do this, a bronchodilator (BL) technique is used, which involves putting a tube of fluid into the lungs of the patient through the mouth and carrying out a pump. Such diagnostic procedures are extremely complex, time-consuming, and costly.
“This is an unrealistic thing. Patients will suffer too much and there is no guarantee of 100% accuracy,” said an anonymous doctor at a hospital in Beijing.
Find the cause
South China Morning Post, citing a South Korean health agency since early April, said the country had detected 160 patients recovering for a second positive result with COVID-19. Similar reports have appeared in mainland China, Taiwan and Hong Kong, as well as in countries like the Philippines and Vietnam.
The World Health Organization (WHO) is investigating why some people who have recovered from COVID-19 are positive for COVID-19. Last week, the WHO said there was no evidence that a person who was infected with COVID-19 was not reinfected again.
Some scientists speculate that re-positive for COVID-19 is due to a test error. They said some of the tools gave false results because there were few specimens on the kit, or because the device was dirty.
Scientists say there are still errors in COVID-19 sampling. Photo: SOUTH CHINA MORNING POST
In addition, last month, a team in China found that in some people who recovered from illness, especially young people, had too few antibodies. Therefore, these people can be reinfected and their resistance cannot fight against the virus remaining in them.
Professor Zhong Nanshan, a leading Chinese respiratory disease expert and scientific adviser to the Chinese government, said that most of the positive test results returned from recovered patients could be due to genes. in fragmented virus.
Zhong Nanshan also said that there is currently no direct evidence of whether a person who is re-positive for COVID-19 can infect others.