Is Omi kerong more susceptible to infection in children? Virology experts: The proportion is higher, and the reasons are not clear

Tianjin is the first to face the local epidemic in Omicron, from January 8 reported two cases of positive infection (one child support institution staff, one primary school student), as of 21:00 on January 9, Tianjin has reported 40 cases of positive infection. Of these, 22 cases of positive infection are all students, accounting for 55% of those who have reported positive infections so far.

At 24:00 on January 8, after analysis and comparison, and confirmed by the Chinese Center for Disease Control and Prevention, the first two indigenous cases of the new coronavirus in Tianjin belonged to the Omi Kerong variant (BA.1 evolutionary branch) and belonged to the same chain of transmission.

At present, half of the children are infected with the Omikejong variant reported in Tianjin, and some experts believe that Omikeron is more likely to infect children. Is this statement scientific? Is the same true of the prevalence abroad?

On January 10, Jin Dongyan, a virologist at the University of Hong Kong, told the surging news (www.thepaper.cn) that from the infection data of Aomi Kerong abroad, it does have a higher proportion of infected people in children, and infected children have been hospitalized and seriously ill, but the reasons for this situation are not clear.

More children are infected than previous strains, and the reasons are unclear

Tianjin was the first city in the mainland to take on Themi kerong, and analysis of those infected is currently lacking. Regarding the situation of child infection, Jin Dongyan mainly judges based on the infection of foreign children.

"Omi kerong is not much more pathogenic than in the past in terms of child pathogenicity, but because more children are infected, more children are hospitalized." Jin Dongyan said that compared with other mutant strains, the situation of Aomi Kerong is prominent. The outbreak of infection among children in the Aomi Kerong mutant strain in Tianjin actually confirmed this.

The phenomenon of child infection with Omikejong is currently analyzed in a variety of ways.

"It's unclear whether it was The Opmi Kerong's special effects that led to the rise in infections in children." Jin Dongyan's analysis, such as whether it is easier to replicate because of Theomilon in children's upper respiratory tract, has not yet been clearly concluded.

Jin Dongyan believes that there are also some more accurate factors such as the lower proportion of children's NEW CROWN vaccinations, and the susceptibility of students to class in confined spaces in winter.

What is the current status of children's COVID-19 vaccinations in Tianjin? Judging from the previously released vaccination data, the vaccination rate in Tianjin is not low. Gu Qing, director of the Tianjin Municipal Health Commission, said that as of December 13, 2021, Tianjin had received a total of 28.398 million doses of the new crown virus vaccine, and the first vaccination rate of people over 12 years old reached 94.9%, and the whole vaccination rate reached 93.9%. COVID-19 vaccination status for children aged 3-11 years has not been disclosed.

On November 13, 2021, at the press conference of the joint prevention and control mechanism of the State Council, Wu Liangyou, deputy director of the Disease Control Bureau of the National Health Commission, introduced that the new crown vaccine for people aged 3-11 has been vaccinated against 84.395 million people, and will strive to complete the full vaccination of people aged 3-11 by the end of December.

In view of the risk of children infecting Omiclon, Jin Dongyan suggested that schools in risk areas should take holidays as soon as possible to avoid cluster outbreaks in schools.

It is recommended to accelerate the development of a COVID-19 vaccine against the Omiljun strain

At present, China has not yet begun to promote the children's new crown vaccine reinforcement needle, and Jin Dongyan also suggested that children should be considered to be vaccinated with the new crown reinforcing needle.

What is more difficult is that the immune effect of the existing COVID-19 vaccine on The Omilon is affected. On 23 December 2021, WHO released a report saying that a number of preliminary studies have shown that some people who have been vaccinated against the new crown virus or infected with other strains of the new crown virus have reduced the immunity effect of antibodies to the Omiljung strain, and many countries have recently reported an increase in the number of cases of secondary infection of the new crown. However, data on the effectiveness of the COVID-19 vaccine in preventing infection with the Aomi kerong strain are still limited, and there is no evidence of peer-reviewed studies.

"The effect of the booster injection will be better, and the strengthening of the target is helpful to reduce severe illness, reduce symptoms, and shorten the detoxification cycle." Jin Dongyan believes that the effectiveness of the vaccine against the Aumechjong variant has decreased, and another effective way to fight is to carry out sequential vaccination of the new crown vaccine, that is, the neutralizing antibody level produced by the "mixed" booster injection will be higher and the protection effect will be better.

Jin Dongyan said that it is more important to accelerate the development of a new crown vaccine against the Aomi Kerong virus, hoping that vaccine companies will quickly step up and regulators can also quickly approve.

According to the previous progress of the approval of the new crown vaccine, clinical trials were carried out in adults first, and then extended to children, so children were vaccinated later than adults.

If we develop a COVID-19 vaccine against Omilon, will we still go through the same process? Jin Dongyan believes that the new new crown vaccine should not only ensure high quality and safety, but also ensure that it is "used for what it is", and it can be used by the people who need it most when it is most needed.

"Covid-19 vaccine development for children should not lag behind that of adults, which is the right thing to do, and the whole world is thinking about this." Jin Dongyan said.