It’s been an awkward time for the head of the Chinese Center for Disease Control and Prevention. Gao Fu was cited over the weekend as telling a health conference that the agency was considering options to improve the efficacy of China’s shots against Covid-19, which was currently “not high.” His remarks, perhaps the first significant hint of official concern over the protection rate offered by homegrown vaccines, were censored. Gao hurriedly gave an interview dismissing the episode as a misunderstanding. But the harm was done — because he was right.
China’s vaccines do appear to shield less effectively than those developed elsewhere. This is bad news for everyone, in a week when Johnson & Johnson’s vaccine became the latest paused over blood-clot concerns. We all need the most populous country in the world to inoculate its citizens, and to succeed in supporting vaccination drives in countries like Indonesia, the worst-infected nation in Southeast Asia. Low efficacy fuels hesitancy and, crucially, makes it harder to achieve herd immunity — the point at which normal life can resume.
But that doesn’t make Beijing’s shots useless. By hoarding vaccines, the Western world has left many in emerging economies uncovered. While more than 848 million doses have been administered, countries with the highest incomes are getting vaccinated 25 times faster than those with the lowest. The United States, with 4% of the world’s population, has 24% of vaccinations, according to Bloomberg’s Covid-19 tracker. For the have-nots, a stopgap shot that may at least keep people out of under-resourced hospitals is well worth it.
First, the problems. Sinovac Biotech Ltd.’s shot posted efficacy levels of just above 50% in a final-stage trial in Brazil, narrowly clearing the minimum required by most regulators. Other Chinese immunizations have delivered rates between 66% and 79%, still below leading Western alternatives. Russia’s Sputnik is above 90%.
Part of the trouble may well be the technology. Inactivated virus vaccines, like Sinovac, use a proven method, but one that generally induces antibody-mediated immunity and requires a substance called an adjuvant to help strengthen the response. Other options do better, particularly cutting-edge shots developed by BioNTech SE/Pfizer Inc. and Moderna Inc., which use messenger RNA to tell the body how to fight Covid-19. China is developing its own mRNA candidates, but the most advanced is only just preparing to begin late-stage trials.
It hasn’t helped that China has been so reluctant to publish peer-reviewed trial data for its main vaccines, making even acceptable rates appear less secure, hard to compare and open for debate.
This is adding up to a significant problem at home. Beijing’s propaganda machine spent months denigrating alternatives and telling people that not only had China made vaccines domestically, but that they were the best. Finding otherwise, as information trickles down, will feed suspicion in a population already hesitant due to past scares.
That matters, given that lower efficacy rates also require a higher percentage of people to receive injections before China can reach levels that protect 1.4 billion. Troublesome vaccine gaps might increase vulnerability, Nicholas Thomas, associate professor at the City University of Hong Kong, told me — especially if people return to old social behaviors, and coronavirus variants come in through regions like the porous border with Myanmar. Informal trade networks reaching into large cities then become vectors for the disease. So far, 179 million doses have been administered in China, far from an official target of vaccinating 40% of the population by the end of June.
The problem stretches abroad, too. With many left behind in the scramble, China has distributed vaccine aid and sold shots to dozens of countries, usually friendly or geopolitically significant often competing with Russia and India. Now, Beijing is dealing with embarrassing questions. Chile, which bet big on Sinovac and has moved quickly to vaccinate, is still seeing high daily infection rates.
Yet while efficacy is important — how a vaccine works in trials — it isn’t everything. Ease of storage, price and availability all matter, too, and there Chinese options do better. Yes, protection rates are less impressive than what cutting-edge vaccines have produced. But they’re not much worse than what we accept for the flu vaccine, for example. Crucially, they prevent people from getting seriously ill.
For emerging economies like the Philippines or Brazil, it’s important to stop infection, but vital to avoid severe cases and to keep people out of hospitals, where they can rapidly overwhelm healthcare networks that are rickety at the best of times. Indonesia, a major recipient of Sinovac doses that needs to vaccinate 180 million people within a year, isn’t wrong that “the best vaccine is the one that’s available.” These are, after all, measures to stop an emergency — almost all of us will require subsequent shots.
Benjamin Cowling, professor at the University of Hong Kong’s School of Public Health, points out that a population that has very high coverage of Sinovac would certainly have far fewer severe Covid cases, even with substantial infection and transmission. That’s a win of sorts.
For those that have the choice, as Hong Kong does, swifter results will come with the more effective vaccine — vital for densely populated spots that require higher percentages to be inoculated. But not everyone has that luxury.
Bloomberg
