China must step up the pace of vaccination against Covid-19 to fill the immune deficit of the population, warned epidemiologist Zhang Wenhong, director of the infectious diseases department of Huashan Hospital in Shanghai.
Zhang told an online event organized by the Brookings Institution in Washington (USA) on Monday (1st) that China has sufficient vaccine production capacity for Covid-19, but the pace of vaccination is a “major concern”.
According to the epidemiologist, vaccine production in the country is expected to increase to 2.1 billion by the end of the year, enough to provide more than one dose per person to the entire population.
“So I don’t think we need to worry about China’s capacity,” he said. But he added: “My biggest concern is the speed of vaccine delivery.”
Even with 10 million doses applied daily, he estimated that it would take up to seven months to vaccinate nearly 70% of the population, a level deemed necessary to achieve herd immunity.
Herd immunity occurs when a high percentage of the community acquires defenses against disease through vaccination and / or previous disease, making it unlikely to spread between people.
In this scenario, even unvaccinated individuals would benefit from some protection as the disease would be unlikely to spread in the community.
The percentage of people who need to be immunized to gain herd immunity varies depending on the disease. For example, against measles, it is necessary that about 95% of the population be vaccinated, while for polio, the number is about 80%. The barrier for Covid-19 is not known, according to the World Health Organization (WHO).
Citing sources at the China Center for Disease Control and Prevention (CDC), epidemiologist Zhong Nanshan also said at the same event that China plans to vaccinate around 40% of the entire population by the end of the month. June.
“It would be nice, but it still takes time to achieve so-called collective immunity,” he said.
“The key point around the world is that people get the vaccine as soon as possible,” said Zhong, who heads an expert group at China’s National Health Commission. “The longer it takes for the population to become immune, the more likely the virus is to mutate. This is a big problem.”
He called on the world to “speed up the production of all vaccines and prepare a new type that works against variants of the virus.”
Since February 9, China has administered a total of 41 million doses of Covid vaccine, according to Zhang, also head of the anti-Covid expert team in Shanghai. This equates to nearly 2 million doses per day, but Zhang said the country should administer at least 5 million doses per day to finish by June.
According to global vaccination data from the British site Our World in Data, China had vaccinated 3.56% of the population on February 27. Israel had vaccinated 92.46%, the United Arab Emirates 60.82%, the United Kingdom 30.13% and the United States 22%.
“China’s current strategy is to promote the establishment of the global immunization effort as part of an internationally coordinated program,” Zhang said. “In the meantime, we will ensure that our vaccination strategies are gradually improved.”
Translation by Luiz Roberto M. Gonçalves