China's COVID-19 Vaccines May Be Less Effective Against Variants

COVID-19 variant

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Key Takeaways

  • COVID-19 vaccines developed by Chinese biotech companies have lower efficacy rates, which may have led to new outbreaks and reinfections in countries that have relied on those vaccines.
  • Public data on these vaccines is scarce.
  • While China's COVID-19 vaccines may be less effective at preventing asymptomatic infection, they may have lowered the severity of these cases.

More than 90 countries have launched their COVID-19 vaccination campaigns with shots made by Chinese biotech companies, Sinopharm and Sinovac Biotech. However, several countries including Seychelles, Chile, Bahrain, and Mongolia are struggling with new outbreaks despite high vaccinate rates, according to the New York Times.

These countries are also dealing with reinfections, especially with the new variants. It’s unclear right now how severe those infections have been,but vaccines with low efficacy rates could be detrimental to the global effort in combating the COVID-19 pandemic, experts say.

“It’s clearly a dangerous situation,” Stanley Weiss, MD, a professor of biostatistics and epidemiology at the Rutgers School of Public Health, tells Verywell. “We need efficient vaccines in those countries to protect their populations. In turn, it helps to protect the U.S. It’s in everyone’s best interest for these vaccines to work well."

Vaccine Efficacy Matters

Currently, three of the authorized COVID-19 vaccines in the U.S. have slightly different levels of efficacy:

  • Pfizer-BioNTech: 94%
  • Moderna: 94.1%
  • Johnson & Johnson: 66.3%

While Sinopharm claimed that its COVID-19 vaccine had a 79% efficacy rate, clinical data is not available to the public. Sinovac's efficacy at prevent asymptomatic infection was 51% in Brazil, according to the World Health Organization (WHO).

“We have not really seen a lot of good data on the efficacy of these vaccines published in general peer-reviewed literature,” John Sellick, DO, an infectious disease expert and professor of medicine at the University at Buffalo/SUNY, tells Verywell.

Vaccines with a lower efficacy would require a vaccinating a higher percentage of the population in order to prevent outbreaks, Sellick suggests. Some countries that have used Sinopharm or Sinovac also tried to reopen too soon. “There are issues of doing too much, too fast, at the same time,” he says.

What This Means for You

Ending the COVID-19 pandemic will require a collaborative and effective global vaccination campaign. You can do your part by getting vaccinated once you're eligible for a COVID-19 vaccine.

The lack of transparent data on the Chinese-made vaccines makes it hard to compare their efficacies to other widely used vaccines like Pfizer, Moderna, and AstraZeneca.

Amesh A. Adalja, MD, an infectious disease expert at the Johns Hopkins Center for Health Security, tells Verywell that Sinopharm and Sinovac may be acceptable when it comes to preventing severe symptoms and hospitalizations, but they may not be "as robust at preventing breakthrough infections."

Gao Fu, the director of China's Center for Disease Control and Prevention, suggested at a news conference in April that the efficacy rates for the Sinopharm and Sinovac vaccines need to improve. “We will solve the issue that current vaccines don’t have very high protection rates,” he said. “It’s now under consideration whether we should use different vaccines from different technical lines for the immunization process."

U.S. Pledged to Donate Vaccines

China has been a major global supplier of COVID-19 vaccines months before the U.S. pledged its support for developing countries. Although the Sinopharm and Sinovac vaccines may offer less protection against new variants, they are still very effective in preventing severe disease and hospitalization.

The Biden administration announced in June that the U.S. will be purchasing 500 million doses of the Pfizer-BioNTech vaccine and donating them to 92 low- and lower-middle-income countries and the African Union.

Shipments are expected to start rolling out in August, and the hope is that 200 million doses will be delivered globally by the end of the year. According to the WHO, about 11 billion COVID-19 vaccine doses are needed to vaccinate 70% of the world’s population. The U.S. donation is still far from meeting the global demand.

“Anything that can be done to get vaccines distributed more widely—especially very high efficacy ones—will be better for everyone overall," Sellick says.

The information in this article is current as of the date listed, which means newer information may be available when you read this. For the most recent updates on COVID-19, visit our coronavirus news page.

6 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Coronavirus Vaccinations. Our World in Data.

  2. Pfizer-BioNTech COVID-19 Vaccine Overview and Safety. Centers for Disease Control and Prevention.

  3. Moderna COVID-19 Vaccine Overview and Safety. Centers for Disease Control and Prevention.

  4. Johnson & Johnson’s Janssen COVID-19 Vaccine Overview and Safety. Centers for Disease Control and Prevention.

  5. World Health Organization. The Sinovac COVID-19 Vaccine: What you need to know.

  6. World Health Organization. Director-General's opening remarks at the G7 Summit - 12 June 2021.

By Korin Miller
Korin Miller is a health and lifestyle journalist who has been published in The Washington Post, Prevention, SELF, Women's Health, The Bump, and Yahoo, among other outlets.