How "ferocious" is the recently popular Delta strain in Guangdong?

At present, the delta variant strain first found in India has been endemic in more than 80 countries, and has also led to community transmission in Guangdong Province, China, which has attracted widespread attention. The results of a large-scale study published june 14 in The Lancet showed that patients infected with delta variants had twice the risk of hospitalization compared with alpha variants, suggesting that delta strains are more transmissible and prone to severe illness after infection.

Indian media also reported that the delta variant strain is also more resistant and can cause symptoms such as blood clots and hearing impairment. So how "ferocious" is the delta mutant strain? Are existing vaccines still effective against delta variant strains? In this regard, the Jiefang Daily Shangguan News reporter interviewed Wang Xinyu, deputy chief physician of the Department of Infectious Diseases of Huashan Hospital affiliated to Fudan University.

It is becoming a major variant of global spread

"Just as humans came out of Africa and gradually evolved into yellow, white, and black people, so did virus mutations." Wang Xinyu said metaphorically that the concept of "poison strain", similar to the concept of human race, is a subtype produced in the process of virus mutation.

Like other organisms, viral mutations are full of accidents, from the beginning of the standard strain constantly mutate, mutation accumulation to a certain level, that is, the production of new strains. Virus mutations are aimless, but once some mutations enhance the spread of the virus, drug resistance and other characteristics, it improves the survival probability of the virus, so the mutant virus will soon spread widely and become the dominant strain.

Coronaviruses are RNA viruses with only one long chain, which is easier to replicate errors than dna viruses with double-stranded, relatively stable DNA viruses, that is, easier to mutate. Before the menacing delta strain, alpha, beta, gamma and other variants were first found in the United Kingdom, South Africa and Brazil.

The three variants of alpha, beta, and gamma are more infectious than standard strains, but delta strains are more transmissible than them. On June 18, Dr. Swaminathan, chief scientist of the World Health Organization, said at a regular briefing that the Delta strain is becoming the main mutant strain spreading globally.

Inactivated vaccines remain effective against delta variant strains

In addition to increased transmission, Indian media reported that the delta variant can cause hearing impairment, gastrointestinal diseases and thrombosis. Wang Xinyu believes that whether the above symptoms are related to the Delta (delta) mutant strain is still debatable, and cannot be simply attributed to the mutated strain, "These 'strange' symptoms widely appear in India's new crown pneumonia patients, and may also be due to the shortage of medical resources and insufficient treatment capacity." ”

For example, Wang Xinyu said that before the Indian new crown pneumonia patients were infected with a large number of mucormycete fungi, a large area of black plaque grew on the surface of the skin, which made many Chinese readers frightened. In fact, mucormycete fungal infection is a complication caused by the patient's untimely treatment and decreased self-resistance, and infection with the new crown virus or other diseases that have not mutated may also cause similar symptoms, which are not related to the mutation of the new crown virus.

So will the vaccine be helpless against the delta variant strain? Theoretically, the impact of virus mutation on THE NMA vaccine may be greater, and the main inactivated vaccines in China at this stage are vaccinated. Studies have shown that China's inactivated vaccines are still effective on alpha, beta and gamma strains, and are also effective against delta strains.

Alarmingly, on June 16, the World Health Organization announced a new variant of the new coronavirus called lambda, which was first reported in Peru and has now been found in 29 countries or regions. The spread of lambda (lambda) mutant strains and the confrontation with vaccines have increased, and more data are needed to evaluate the protective effect of Inactivated vaccines on lambda variants in China. Wang Xinyu said: "The game process between vaccines and viruses is dynamic, and a vaccine cannot guarantee that it will be done once and for all. However, the level of vaccine research and development in China is trustworthy, and everyone need not worry. ”

Column Editor-in-Chief: Huang Haihua Text Editor: Shi Jiani Title Image Source: ic photo Image Editor: Xu Jiamin

Source: Author: Shi Jiani