A container loaded with Sinovac vaccine doses is offloaded from a plane at Jakarta’s airport for human trials in Indonesia. Photo: Handout

Conflicting messages from experts and officials running the Chinese National Center for Disease Control and Prevention have sown further confusion among the Chinese population, who already had a flimsy understanding and trust in homegrown Covid vaccines. 

Chinese CDC chief Gao Fu may have inadvertently incurred Beijing’s wrath after he candidly admitted at a recent forum the mediocre efficacy rates of vaccines approved for mass inoculations against Covid-19 by his peers at the National Medical Products Administration.  

Gao did not dodge questions at the symposium about the less-than-impressive potency rates of between 50.65% and 79.34% of the three attenuated drugs from SinoPharm and Sinovac. He revealed new plans being mulled to boost protection and gain people’s trust and thus the take-up.

However, believed to be under political pressure, he said on Monday that the media had “misquoted” him and he had full confidence in the indigenous jabs, adding that he also had these shots.   

Still Gao, faced with incredulity from health pundits, his subordinates and the public, had suggested during the forum that vaccines from different suppliers, with different ingredients and even from different technical lines, could be mixed and administered to set off immune systems more effectively. 

Going against this is the latest revised vaccination guidelines from the national CDC, published in February for a nationwide roll-out, which stipulate a strict type and supplier consistency with the first and second shots.

Chinese CDC chief Gao Fu. Photo: Xinhua

A public health and immunology specialist with Shanghai’s municipal CDC told Asia Times that the guidelines even prohibited mixing up jabs from SinoPharm and Sinovac, even though their products belonged to the attenuated type with basically identical formulas.   

“But almost overnight we have a National CDC chief talking about giving another type of drug to those who already received their first dose, and his remarks may do a disservice to our hard work to try to drum up trust and take-up,” said the expert, who declined to be named as he was not authorized to speak to the media.

“We have already been asked by residents at community vaccination centers if doctors can use aspirin to treat a flu patient on day one but give him Chinese medicine instead on the following day.”

He wondered about Gao’s spur-of-the-moment idea, adding that no clinics or medical centers in Shanghai had started mixing different drugs and cautioned that the side effects of one type of Covid vaccine had not been fully understood, let alone the risks from mixing shots. 

State media including the Global Times and Caijing magazine all noted on Monday and Tuesday that Gao’s proposal was not “frivolous,” adding that other countries had also been considering similar options to boost protection. 

Previously, the University of Hong Kong’s medical school launched a frontier study to investigate changes to protection and the potential health impact if two different types – in the city’s case, BioNTech’s messenger ribonucleic acid (mRNA) vaccine and Sinovac’s attenuated ones – were given to the same person.

Gao’s remarks, nonetheless, may also herald the arrival of a new homemade drug, the one-shot adenovirus vector vaccine co-developed by the People’s Liberation Army (PLA) and CanSinoBio, a Tianjin-based listed pharmaceutical firm, and approved for conditional use by regulators earlier this year.  

The novel vaccine containing artificial viruses in the form of adenoviral vectors can shuttle a gene from SARS-CoV-2, the coronavirus that causes Covid-19, into our bodies where cells can read it and make coronavirus spike proteins to trigger an immune response.

Still, the new drug is said to be between 65.28% and 68.83% effective in limited clinical trials, according to Caijing magazine that viewed related filings with state drug watchdogs, and thus its protection is indeed lower than SinoPharm’s more traditional attenuated jabs, whose immunogenicity is 79.34%. 

The Shanghai CDC expert reckoned that a possible combination could be a shot from SinoPharm or Sinovac as the first dose, followed by the PLA-CanSinoBio’s drug as a booster dose, if Gao’s controversial proposal was adopted.  

People receive shots of homegrown vaccines inside a community health center in Beijing. Photo: China News Service

Xinhua also confirmed on Tuesday that China’s own mRNA candidate had entered its clinical trial as early as June 2020, after the PLA’s researchers partnered with private firms in Suzhou and Yunnan for a joint endeavor.

Citing National CDC Chief Public Health Planning Officer Wang Huaqing, the state news agency reported that trials and a regulatory review could be finished by the end of the year, ideally before this fall, to offer one more option for China’s expanded immunization drive and to take on more mutant strains. 

Gao, who was critical of mRNA shots like those from BioNTech, Pfizer and Moderna in a China Central Television interview last year, did not hide his newfound interest in the cutting-edging technology when addressing a vaccine conference on Saturday. 

“There are endless possibilities with mRNA technologies. We cannot stop exploring and trialing new solutions even though we have traditional vaccines in hand because Covid doesn’t stay in one way [of infections] for long,” he said. 

About 167 million doses have been given nationwide as of April 11. Yet that amount only comes to about 12% of China’s population.

China’s goal is to vaccinate 40% of its people by the end of June. Beijing must increase the take-up amid public hesitancy. Beijing also has its work cut out to quell doubts in countries in the developing world, from Pakistan to Indonesia to Brazil, that are taking deliveries of SinoPharm and Sinovac’s jabs.  

One high-profile case in which SinoPharm’s shot failed to offer protection involved Pakistan’s Prime Minister Imran Khan, who came down with the disease last month after getting his first dose. There are suggestions, however, that the leader could have contracted the pathogen before or shortly after his injection.

Read more: China’s end-June 40% vaccination goal a long shot