The recent outbreak of the epidemic in Hong Kong and South Korea, the culprit points to the Omicorn subtype BA.2, including even the US CDC monitoring also found that the number of BA.2 cases increased significantly, many people worry about whether BA.2 will cause another wave With the resurgence of the epidemic, Huang Gaobin, deputy director of the Infection Control Center of the Hospital Affiliated to China Medical University, said: “Don’t be too nervous in the face of BA.2. At present, it seems to be more infectious, and many of its characteristics are very similar to BA.1.”

What is BA.2?

Omicron types include BA.1, BA.2, and BA.3. In short, BA.2 is a subtype of Omicron. In the past, Omicron mainly refers to the virus strains that are prevalent in the world by BA.1. As the epidemic evolved, the number of cases in BA.2 gradually increased, even surpassing that in BA.1.

BA.2 does have obvious mutations in the receptor binding position, which is different from BA.1, but there is no evidence of toxicity in toxicity.

BA.2 has different symptoms? High transmission power?

From the monitoring of the US CDC, it was found that the severity of the disease caused by BA.2 and BA.1 was not much different. The common symptoms after the main infection were headache, sore throat, sneezing, runny nose, and body pain.

However, the US National Library of Medicine pointed out that BA.2 has two other symptoms that are more different: Dizziness and fatigue, especially BA.2’s transmission power is indeed increased by about 30% compared with BA.1, and many characteristics of BA.2 are similar to BA. .1 is very similar. The US CDC report emphasized that although BA.2 has a relatively strong transmission power, it will not increase the number of cases like Omicron when it came out, and the clinical symptoms are not worse than BA.1.

Can a vaccine protect against BA.2?

The recent outbreak in Hong Kong has caused people to think that the vaccine has failed?

Hong Kong is mainly a large number of infections among the elderly. They may not have been vaccinated, or they may have been vaccinated by Sinovac, but Sinovac vaccine data shows that compared with other WHO-certified vaccines, the human body produces antibodies and has a weaker immune response. Over time, the protection may be poor.

Vaccines and medicines are still important strategies and means to prevent COVID-19. After the first dose, the group should take the second dose. The two doses are our basic doses, which allow the body to develop immunity and memory. The third dose depends on the second dose. If there is a difference of more than six months between the time, try to play as soon as possible to increase the memory of the body.

BA.2 may be “reinfected”?

Due to the fear of repeated infection due to BA.2 antigen changes, a previous study by the Danish CDC found that Delta and BA.1 recovered patients were still at risk of re-infection with BA.2, and found that among 263 patients who were re-infected with new coronary pneumonia, 190 of them were caused by BA.2.

Studies have shown that people who have recovered from BA.1 may be re-infected with BA.2, but this is very rare. If they have been infected with BA.1, even if the symptoms after repeated infection are relatively mild, they may be mild or even asymptomatic. Don’t worry too much about BA.2, consider him a kind of Omicron. “