Recently, the international authoritative medical journal The Lancet published an article entitled "where is the next sars-cov-2 variant of concern?" Comments for. The comments indicated that a new coronavirus novel coronavirus variant may be evolving in a new coronavirus infected person with low immunity: it is highly infectious and can challenge existing immunity and therapies**
This review article gathered a large number of experts in the field of virus research, including ravindra K Gupta of Cambridge University, Thomas P peacock of Imperial College London in the United Kingdom, William hanage of the school of public health of Harvard University, etc. The commentary said that the new crown pandemic is characterized by waves of new virus variants sweeping the world. The ultimate source of these mutations is uncertain, but preliminary evidence shows that at least some of them come from long-term infected people with novel coronavirus, such as some infected people with low immune function. This phenomenon can be observed in them.
The review called that the most urgent task in the world at present is to provide high-quality medical care for those long-term infected with novel coronavirus, and give priority to providing them with curative treatment. If these long-term novel coronavirus infected persons are not properly managed, it will bring risks to personal and public health.
The lancet article explains that the immune system of people with low immune function, such as patients infected with AIDS virus (HIV) or recipients of organ transplantation, may be difficult to eliminate the persistent infection of novel coronavirus. Preliminary data show that the infection of novel coronavirus in patients with low immunity usually lasts for several months. Over time, novel coronavirus will continue to acquire new mutations, because they may escape immune-mediated neutralization and hone their ability to infect human cells.
At the same time, because the size of the virus population in the persistent infection of patients with low immunity is not limited by the transmission bottleneck, compared with the general population, the mutation speed of novel coronavirus will be faster, so this persistent mutation usually causes the virus to produce considerable genetic novelty. Although the evolutionary pressure of the virus in a single host may be different from the adaptation of transmission between hosts, it is reasonable to assume that the next "mutant of concern (VOC)" may come from an infected population with high genetic diversity and drug resistance.
For example, "VOC" alpha (b.1.1.7) appeared in the UK. Even compared with the common ancestor virus closest to alpha, alpha showed a high degree of difference: it accumulated a series of mutations with worrying characteristics, and its speed was faster than other new crown mutants at that time.
As early as june2020, virologist Gupta of Cambridge University had noticed a similar situation. At that time, a patient he treated was admitted to the hospital a month ago due to COVID-19, and continued to detoxify during the hospitalization. This patient was previously treated with rituximab for recurrence of lymphoid carcinoma. This drug will deplete his antibody producing B cells, which makes it difficult for him to fight the persistent infection of novel coronavirus.
Gupta studied the problem of drug resistance to AIDS, which made him curious about this special new crown case. He tried to treat the patient. Despite being given the antiviral drug rimcivir and two rounds of plasma therapy, the patient died 101 days after diagnosis in august2020. When Gupta studied the genome sequence of the novel coronavirus in the patient, he found that the virus had obtained a series of mutations, which may make it have stronger immune escape ability. Gupta will soon publish his research results in the form of papers, which has become an important reference for researchers in various countries to try to understand the origin of alpha.
Gupta gave the world a wake-up call at that time: it is necessary to pay attention to the potential role of immunocompromised people in the new crown pandemic. If this population provides an opportunity for the evolution of the pedigree of novel coronavirus, and the newly generated pedigree spreads faster and is more pathogenic, these chronic new coronavirus infections not only pose a risk to patients, but also may change the process of the new coronavirus pandemic.
However, nearly two years have passed, and the situation has not changed. Generation after generation of new mutants suddenly rose in an inconspicuous position in the evolutionary tree, and quickly replaced the previous "concern mutant (VOC)", sweeping the world. When the global epidemic strain of delta (b.1.617.2) was almost unified, its distant relative Omicron (b.1.1.529) had about 45 mutations, which separated Omicron from its ancestor strain. The previous beta (b.1.351) and gamma (P.1) were also isolated from their recent ancestral strains, and there were also many mutations.
It is worth noting that delta originated in India and Omicron originated in South Africa. The public health conditions in both countries need to be improved, and there is a lack of continuous monitoring of the virus genome sequence. South Africa has the largest number of people with low immunity in the world - people living with AIDS virus. Available information shows that there are 7million people living with AIDS in South Africa, accounting for about 13% of the country's population.
The review of the lancet finally called for: it is very important to cure the new coronal infections with low immune function, because they may carry the next new coronal variant, a new variant with high infectivity, and challenge the existing immunization and therapy.
World Health Organization epidemiologist Maria van korhoff also said earlier that all countries should do their best to minimize the spread of novel coronavirus. "The more this virus spreads, the greater the chance it will mutate." "We are playing a very dangerous game," said Maria van korhoff
Author: heliping source: surging news