AZ in the UK: Major Pro’s, Minor Con’s

With Pfizer shots in high demand and short supply across Australia, the AstraZeneca (AZ) vaccine is now taking a major place in our Covid-19 vaccination roll-out. With the pause and then recommencement of the AZ roll-out, you might be wondering, is this for better or worse?

Pro’s and Con’s of an AstraZeneca-heavy Vaccine Roll-Out

Well, we don’t have to wonder, because Australia happens to be eight and half months behind the UK on this. Slightly more than half of the UK’s vaccinations have been AstraZeneca, which gives us a great insight into how things are going to go here.

The UK has administered 24.8 million first doses of AZ and around 24 million second doses. Thanks to a fortuitous “dosing error,” the AZ team stumbled upon a half-dose then full-dose schedule that makes recipients 90% less likely to develop a symptomatic case of Covid-19.

UK health department modelling estimates the vaccination program prevented 27,200 deaths in the six months from December 2020 to June 2021. The same modelling estimates a reduction in infections to the tune of 7,151,000 less cases. 

UK government modelling on the effect of mass vaccination on Covid-19 deaths.

Covid-19 vaccine studies were not able to measure whether or not vaccinated people transmit the virus. However, according to the UK report authors, the data suggest that vaccines do reduce transmission.

Saving 27,200 lives and millions of cases of illness is a major win on any measure. But what about the much debated safety concerns relating to blood clots?

UK Data on AstraZeneca Side-Effects

The UK’s Medical and Healthcare Regulatory Agency (MHRA) runs a Yellow Card system that allows patients and practitioners to report side effects from vaccines and other medicines. Of the 24.8 million Brits administered an AZ vaccine, there have been 229,134 reporting side effects, or 0.92%.

Technically that figure includes any minor side effect, like a sore arm. However, reactions that don’t require medical response or review are probably unlikely to be reported.

Clotting remains the most serious concern, and is sure to weigh on the mind of everyone who falls within that 0.92% who feel unwell after getting the shot.

Up to 18 August 2021, there have been 417 cases of “major thromboembolic events” (blood clots) following the AZ vaccine. According to the MHRA, “Of the 417 reports, 210 occurred in women, and 203 occurred in men aged from 18 to 93 years. The overall case fatality rate was 17% with 72 deaths.” That’s around 2.9 deaths per million AZ vaccinations.

In sum, yes it would have been great to have the entire country vaccinated with Pfizer, Moderna and potentially Novavax. But AZ is still a major benefit to Australia and any country where the coronavirus is circulating.

Follow Christian on Twitter for more news updates.

If you’d like to receive an occasional Free email with more content like this, then sign up today!