Hong Kong University Yuan Guoyong: “Omi Keron” may be more contagious than Delta, the existing vaccine is still effective

The first two Omicron patients in Hong Kong received two doses of BioNTech vaccine within six months and developed very mild symptoms. Their antibody levels also rose at least tenfold four to seven days after admission.

Yuan Guoyong, Chair Professor of the Department of Microbiology, Faculty of Medicine, University of Hong Kong, stated on December 1 that “Omicron” (Omicron variant virus strain) may be more contagious than the Delta variant. The research team led by him announced on November 29 that it had successfully isolated the SARS-CoV-2 Omicron virus variant from clinical specimens, and it was only four days after the two imported cases of related variants appeared in Hong Kong on November 25. The research team is further amplifying and purifying the virus strain to obtain a larger number of variant viruses for subsequent experiments.

The cultured virus will be used in animal models to evaluate its transmission, immune escape and pathogenicity, and help test the efficacy of monoclonal antibody therapy. The team stated that it is negotiating with a vaccine company in the Mainland to use the mutant strain for the development and production of an inactivated whole virus vaccine.

Regarding whether the appearance of the Omicron variant virus in Hong Kong will affect customs clearance with the mainland, Yuan Guoyong said that the factor affecting customs clearance is the number of cases in the two places, not the appearance of a certain variant virus. He also said that due to the lack of awareness of Omicron, the policy still needs to be adjusted according to the overall situation of the global epidemic.

Consider that the Omicron mutant virus strain has spread in many countries around the world. The Hong Kong Special Administrative Region government has listed countries and regions with confirmed cases of Omicron as high-risk areas in Group A. The Special Administrative Region government announced on December 2 that Finland, Ghana, South Korea, Norway and Saudi Arabia will be added to designated areas in Group A. In December Effective at midnight on the 5th. Non-Hong Kong residents who have stayed there within 21 days are not allowed to enter the country. Hong Kong residents must have completed the vaccination and hold an approved vaccination record before boarding the flight back to Hong Kong, and undergo a 21-day compulsory quarantine upon arrival in Hong Kong, during which they undergo 6 tests, and must go to a community testing center on the 26th day of arrival in Hong Kong Accept mandatory testing.

Omicron is more infectious or higher than Delta

Hong Kong has so far found 4 patients infected with the Omicron variant, of which 3 were found during isolation in a hotel, and the other was a transit passenger.

In Hong Kong on December 1, another imported case involving the new variant virus Omicron was the aforementioned transit passenger. The confirmed case was a 38-year-old male patient. The patient traveled to Nigeria in Papua New Guinea in mid-November. He arrived in Hong Kong from Qatar on November 24 and waited for a transfer. He stayed in the restricted area of ​​Hong Kong International Airport due to visa-related issues. After staying for 4 days, he was subjected to pre-departure testing in the restricted area. The result was positive, and he had not been vaccinated against the new crown vaccine. After testing by the Hong Kong Department of Health, it was confirmed that the case contained the Omicron mutant virus strain.

Yuan Guoyong revealed that according to the first two new variants of the Regal Hotel in Hong Kong, “they (infected) have never opened the door at the same time, they have never seen each other, they have never shared anything, but they Still infected.” He called the spread “surprisingly remote”, “This is obviously an air (spread) situation. We are worried that the spread of this virus may be higher than the Delta virus.”

But he also reminded that the above conclusions may not be representative, because they are only based on the transmission findings between the two cases. About a dozen guests who lived on the same floor of the isolation hotel as the two cases of infection have been sent to the SAR government’s Penny’s Bay Quarantine Center, but no one has tested positive so far.

Existing vaccines are still effective

Yuan Guoyong and his team said that the existing vaccines are still effective against Omicron. The first two Omicron patients in Hong Kong received two doses of BioNTech vaccine within six months and developed very mild symptoms. Their antibody levels also rose at least tenfold four to seven days after admission.

Yuan Guoyong said: “From the perspective of immune memory, this is very satisfactory.” In his opinion, if the mRNA vaccine has been vaccinated and the Omicron variant is infected, the immune response is mobilized very quickly.

Regarding whether the existing new crown vaccine in Hong Kong is still effective, Yuan Guoyong believes that when facing Omicron, more vaccines may be needed, especially those who have been vaccinated with two doses of Kexing vaccine. He said that Kexing uses inactivated technology, and most of the previous inactivated vaccines require at least three to four shots to have sufficient protection. Only when the Omicron virus is developed into a new vaccine, will there be better protection.”

Since February this year, Hong Kong started the new crown vaccination plan, but progress was not satisfactory, and it did not reach the 70% vaccination rate target until November 23. At present, the population who has received the first shot is about 4.76 million, accounting for 70.7%, and the second shot is only 67.4%. At the same time, the vaccination rate of elderly people as a high-risk group has been hovering at a low level. Among the 70-79-year-old population, only 44.82% have received the first shot, while the vaccination rate for people over 80 is only 17.65%. .