Breakthrough Covid-19 infections a ‘small risk’ for inoculated people

Medical experts emphasised that Covid-19 vaccines are extremely effective and the only way to end the pandemic.

Several scientists gave their views about the importance of being inoculated after “breakthrough cases”, when a vaccinated person becomes sick or dies from coronavirus-related illness, were reported in the US and India.

The latest data adds to previous evidence that the vaccines, while not offering 100 per cent protection against Covid-19, significantly cut the risk of serious illness and death.

Official figures show that small numbers of vaccinated people around the world have died, but such reports have been taken out of context and blown out of proportion.

“The vaccines are highly effective, remarkably effective, including the vector-based and mRNA [messenger RNA] ones,” said David Taylor, professor emeritus of pharmaceutical and public health policy at University College London.

“If something isn’t 100 per cent effective, it doesn’t mean it should be blamed for unfortunate individuals who don’t respond well.”

The US Centres for Disease Control and Prevention publishes the number of breakthrough infections in the US.

These are people affected by the virus after receiving a second vaccine dose at least two weeks earlier.

In its latest update, released last Friday, the CDC said it received reports of 9,245 breakthrough infections. It said 132 of those patients died.

For 20 of those deaths, the infection was asymptomatic or the person died from something other than Covid-19.

Overall, more than 590,000 people in the US have died of Covid-19 or complications stemming from it.

“If it’s one in a million or two or three in a million, you’re looking at unusual biology,” Prof Taylor said.

“It’s probable that if the people were fully vaccinated and have been vaccinated for some time and they’ve fallen victim to the disease, they would’ve fallen victim anyway.”

India, where there has been a surge in infections, does not publish the number of deaths from breakthrough cases.

But health authorities estimated that between two and four people in every 10,000 who are vaccinated are infected with the virus.

Last month, India recorded 180 deaths among people inoculated against the disease, but that included people who died from potentially unrelated illnesses. The figures were largely taken out of context on social media.

More than 103 million people in the US have received two vaccine doses. That suggests that about one in a million fully vaccinated people contracted Covid-19 and died.

The CDC said that vaccine breakthrough cases “occur in only a small percentage of vaccinated persons”.

It recommends that fully vaccinated people continue to wear masks, maintain social distancing, wash their hands often and avoid crowds and poorly ventilated spaces.

Last week, the CDC released findings indicating that being vaccinated reduced the risk of being admitted to hospital with Covid-19 by 94 per cent in people aged 65 or above.

Using data from two US healthcare networks with 24 hospitals in 14 states, a CDC study found that people who received their first shot at least two weeks earlier were 64 per cent less likely to require hospital treatment if they contracted the disease.

The CDC said the results, which related only to people vaccinated with the PfizerBioNTech or Moderna mRNA vaccines, were the first real-world findings in the US to confirm the effectiveness of those types of vaccines at preventing serious illness.

In February, the US authorised the use of another vaccine, from the Johnson & Johnson subsidiary Janssen.

If something isn’t 100 per cent effective, it doesn’t mean it should be blamed for individuals who don’t respond well PROF DAVID TAYLOR University College London

Like the Oxford-AstraZeneca and Sputnik V vaccines, the Janseen shot was developed using non-replicating adenoviruses that cannot cause infection.

In other countries where large proportions of the public have been inoculated, including Israel and the UK, death rates dropped.

Factors such as lockdowns also played a part in tackling the spread of the virus in those countries.

The UAE, which has one of the highest vaccination rate in the world, reported a decline in deaths last month after a peak in February.

Prof Taylor said a mix of safety measures could be required over the next two or three years to control the pandemic, including mass vaccination and behavioural measures such as social distancing and mask-wearing.

“I think the key will be if we can get oral drugs that will control the disease early. That will be the big game-changer,” he said.

“Probably by the end of this year, we’ll be looking at a situation where we’ve got drugs that can be used early and effectively on a mass scale.”