Back to Africa Check

Pfizer Covid vaccine has efficacy of just 12%? No, screenshot of Global News headline fake

“Pfizer clinical trial data reveals the company’s Covid vaccine has a 12% efficacy rate,” reads the headline on what seems to be a screenshot of an article by the Canadian news website Global News, circulating on social media since May 2022.

It shows a generic photo of a row of Covid-19 vaccines with the Pfizer logo behind them.

Text below reads: “Despite claims from Pfizer CEO Albert Bourla and countless public health officials that the efficacy of the vaccine was nearly 100%, the findings of the company’s clinical trial data show it was less than 12%.”

The Pfizer-BioNTech Covid vaccine is used in at least 179 countries. In South Africa, about 27.7 million doses of the vaccine – first, second and booster shot – have been administered.

But did Global News really publish an article revealing that Pfizer’s own data found its vaccine had an efficacy rate of less than 12%? We investigated.


Article ‘never published on our site’

A Google search for the screenshot's headline returned no Global News articles. We searched the site itself and again came up empty.

What we did find was a Global News article from November 2020 with the headline: “Pfizer says final results show coronavirus vaccine is 95% effective, no safety concerns.”

A Global News spokesperson told Reuters that the site had not published the article. “We can confirm that the headline and caption in question were never published on our site and they are falsely associated with the Global News brand.”

The screenshot is fake. But what about the claim about the Pfizer-BioNTech vaccine’s efficacy?

Efficacy of 95% – but booster shot still needed

“The Pfizer BioNTech vaccine against Covid-19 has an efficacy of 95% against symptomatic Sars-Cov-2 infection,” the World Health Organization (WHO) says. Sars-Cov-2 is the coronavirus that causes Covid-19.

The vaccine is proven safe, the WHO says, and significantly reduces Covid hospitalisations and deaths.

In February the US Food and Drug Administration gave emergency authorisation for the Pfizer-BioNTech vaccine to be given to children aged six month to under four years. The jab has an efficacy rate of 80.3% in this age group.

Yale University in the US explains that while the two-dose vaccine does have an efficacy rate of 95%, its protection wanes over time. So it’s important that adults get a third booster shot, which “brings the immune system back to robust level”, the university says.

Republish our content for free

We believe that everyone needs the facts.

You can republish the text of this article free of charge, both online and in print. However, we ask that you pay attention to these simple guidelines. In a nutshell:

1. Do not include images, as in most cases we do not own the copyright.

2. Please do not edit the article.

3. Make sure you credit "Africa Check" in the byline and don't forget to mention that the article was originally published on

For publishers: what to do if your post is rated false

A fact-checker has rated your Facebook or Instagram post as “false”, “altered”, “partly false” or “missing context”. This could have serious consequences. What do you do?

Click on our guide for the steps you should follow.

Publishers guide

Africa Check teams up with Facebook

Africa Check is a partner in Meta's third-party fact-checking programme to help stop the spread of false information on social media.

The content we rate as “false” will be downgraded on Facebook and Instagram. This means fewer people will see it.

You can also help identify false information on Facebook. This guide explains how.

Add new comment

Restricted HTML

  • Allowed HTML tags: <a href hreflang> <em> <strong> <cite> <blockquote cite> <code> <ul type> <ol start type> <li> <dl> <dt> <dd> <h2 id> <h3 id> <h4 id> <h5 id> <h6 id>
  • Lines and paragraphs break automatically.
  • Web page addresses and email addresses turn into links automatically.
limit: 600 characters

Want to keep reading our fact-checks?

We will never charge you for verified, reliable information. Help us keep it that way by supporting our work.

Become a newsletter subscriber

Support independent fact-checking in Africa.