Five high-new coronavirus vaccination countries rely on Chinese vaccines

An analysis by CNBC shows that among countries with high vaccination rates and Covid-19 infection rates, most countries rely on vaccines made in China.

Research results come from the efficacy of Chinese vaccines Facing increasingly stringent scrutiny, Coupled with the lack of data on their protection against more easily disseminated delta variants. CNBC found that population-adjusted weekly Covid cases are still high in at least six countries/regions with the highest vaccination rates in the world-five of them rely on vaccines from China.

As of July 6, CNBC has identified more than 1,000 new confirmed cases per million people per week in 36 countries/regions, using data from Our data world, It brings together information from sources such as the World Health Organization, the government, and Oxford University researchers. CNBC then identified countries in these 36 countries where more than 60% of the population had received at least one dose of Covid vaccine.

These countries rank six, five of which use Chinese vaccines as an important part of their national vaccination plan: United Arab Emirates, Seychelles, Mongolia, Uruguay and Chile. One of the countries that does not rely on Chinese vaccines is United Kingdom.

At the same time, the UK has approved vaccines for Moderna, AstraZeneca-Oxford, Pfizer-BioNTech and Janssen.The number of Covid cases in the UK has surged in recent weeks because More spreadable delta variants are already spreading there.

Sinopharm and Kexing did not respond to CNBC’s request for comment.

In countries with high vaccination rates, several factors may contribute to a surge in Covid cases. Vaccines cannot provide 100% protection, so people who are vaccinated may still be infected. At the same time, new variants of the coronavirus may be better than vaccines.

Epidemiologists say that countries should not stop using the Covid-19 vaccine from China, especially when the vaccine supply is limited in low- and middle-income countries.

Many countries and regions where Sinopharm and Kexing have approved vaccines are developing countries and cannot compete with wealthier countries for vaccines developed in the United States and Europe.

Ben Cowling, a professor at the School of Public Health at the University of Hong Kong, said that countries may decide to use certain vaccines based on their long-term goals.

Colin, the head of the school’s epidemiology and biostatistics department, told CNBC in an email: “As long as the number of severe COVID-19 cases and deaths is relatively small, some countries may accept low levels of circulation.” “This It should be possible with high coverage of any available vaccine.”

Nevertheless, some countries are still avoiding China’s vaccines.Costa Rica month Refusal to deliver vaccine ZTE thinks the effect is not good enough after development.

The World Health Organization approved Sinopharm and Kexing’s vaccines for emergency use.

Both Chinese vaccines are less effective than Pfizer——Biological Technology with Modern, Both have shown more than 90% efficacy.

Sinopharm’s vaccine has an effective rate of 79% The WHO states that it can fight symptomatic Covid infections, but its effectiveness for certain groups (such as people 60 and older) is unclear.This The efficacy of Huaxing injection There are about 50% to more than 80%, depending on the country/region where the trial is conducted.

Experts say that the results of clinical trials cannot be directly compared because the settings of each trial are different. However, a Hong Kong study found that people who received the BioNTech vaccine had “significantly higher” antibody levels than those who received the Sinovac vaccine. “South China Morning Post” reported.

Some experts suggest that the technology behind different Covid vaccines can explain the differences in their effectiveness.

Sinopharm and Kexing’s vaccines trigger an immune response by exposing the body to weakened or “inactivated” viruses. Tried and tested method This has been used by vaccines for decades. Pfizer-BioNTech and Moderna’s vaccines are based on a technology called messenger RNA, which instructs the body to make viral proteins that induce immune responses.

Michael Hyde, a senior researcher in global health at the University of Southampton in the United Kingdom, said: “Inactivated vaccines are easy to manufacture and are known for their safety, but they tend to produce weaker immune responses compared to some other vaccine types.” Wrote in an article Published on the conversation website.

Kaolin said that despite this, large phase III clinical trials have shown that inactivated vaccines are “highly effective” against serious illnesses and deaths from Covid.

The professor told CNBC that in some countries that use Chinese vaccines, the surge in Covid cases “is often a surge in mild infections, and people who are fully vaccinated rarely have severe cases.”

When the vaccine is less effective, more people need to be vaccinated to achieve “herd immunity.” This happens when the virus no longer spreads rapidly, because most people have been vaccinated or recovered from infection.

Some countries have decided to try to achieve herd immunity in the early stages of the pandemic, but no country has succeeded yet. Some people say they will achieve herd immunity, Like Sweden, Eventually becomes Compared with neighboring countries, Covid has been hit harder This is the vaccination route.

A study by the Kirby Institute at the University of New South Wales It is claimed in Sydney that in New South Wales, Australia, if 66% of the population is vaccinated with a vaccine that is 90% effective against all infections, herd immunity can be achieved.

Studies have shown that if the vaccine efficacy reaches 70%, the proportion of people who need to be vaccinated will rise to 86%, and if the vaccine efficacy is less than 60%, herd immunity cannot be achieved.