Tag: vaccine effectiveness

Study finds COVID-19 vaccines are ‘highly effective’ in most people in clinical risk groups

Those used in the UK as effective at preventing symptomatic disease in the majority of people with underlying health conditions as the rest of the population

The study from Public Health England (PHE) included more than 1 million people in at-risk groups.

Within these clinical risk groups, there will be people with more severe forms of illness – particularly in the immunosuppressed group – who may not respond as well to the vaccines, and we recommend they seek advice from their specialists.

The study found:

  • overall vaccine effectiveness against symptomatic disease in risk groups is approximately 60% after one dose of either AstraZeneca or Pfizer-BioNTech, with little variation by age
  • after 2 doses, vaccine effectiveness is 81% with AstraZeneca in people in risk groups aged 16 to 64. No data is available for Pfizer-BioNTech
  • in people in risk groups aged 65 and over, vaccine effectiveness with Pfizer-BioNTech is 89% and 80% with AstraZeneca
  • for those who are immunosuppressed, vaccine effectiveness after a second dose is 74%, with similar protection to those who are not in a risk group. This rises from 4% after a first dose

Although age is the greatest risk factor for adverse outcomes following coronavirus (COVID-19) infection, certain health conditions also increase the risk of severe disease.

Diabetes, severe asthma, chronic heart disease, chronic kidney disease, chronic liver disease, neurological disease, and diseases or therapies that weaken the immune system – such as blood cancer, HIV or chemotherapy – have all been linked to an increased risk of hospitalisation or death with COVID-19.

People with these conditions who are at highest risk were initially advised to shield during the peak of the pandemic and all risk groups were then prioritised for vaccination. The government announced the dose interval would be brought forward from 12 to 8 weeks for the clinically vulnerable on 14 May, and everyone in these groups should now have been offered a second dose.

Data on vaccine effectiveness among people in clinical risk groups was previously limited. Though more data is needed, protection against hospitalisation and death in risk groups is expected to be greater than protection against symptomatic disease, as has been seen in studies of the general population.

Dr Mary Ramsay, Head of Immunisation at PHE, said: “This real-world data shows for the first time that most people who are clinically vulnerable to COVID-19 still receive high levels of protection after 2 doses of vaccine.

“It is vital that anyone with an underlying condition gets both doses, especially people with weakened immune systems as they gain so much more benefit from the second dose.”

The Joint Committee on Vaccination and Immunisation (JCVI) advised that those living with immunosuppressed adults should be prioritised for vaccination to help limit the spread of the virus to people in this group.

If the planned booster programme goes ahead, the JCVI has recommended that immunosuppressed adults and their household contacts should also be among the first to be offered a third dose of vaccine in September.

PHE estimates that 30,300 deaths and 8,151,000 infections have been prevented as a result of the COVID-19 vaccination programme, up to 25 June. This is based on modelling analysis from PHE and Cambridge University’s MRC Biostatistics Unit.

PHE also estimates that 46,300 hospitalisations have been prevented in people aged 65 or older in England up to 27 June (approximately 7,000 admissions in those aged 65 to 74, 18,000 in those aged 75 to 84, and 21,300 in those aged 85 and over).

Vaccines are ‘highly effective’ against Indian variant

New study shows that 2 doses of the COVID-19 vaccines are highly effective against the B.1.617.2 variant first identified in India

Vaccine effectiveness against symptomatic disease from the B.1.617.2 variant is similar after 2 doses compared to the B.1.1.7 (Kent) variant dominant in the UK, and Public Health England expect to see even higher levels of effectiveness against hospitalisation and death.

The study found that, for the period from 5 April to 16 May:

  • the Pfizer-BioNTech vaccine was 88% effective against symptomatic disease from the B.1.617.2 variant 2 weeks after the second dose, compared to 93% effectiveness against the B.1.1.7 variant
  • 2 doses of the AstraZeneca vaccine were 60% effective against symptomatic disease from the B.1.617.2 variant compared to 66% effectiveness against the B.1.1.7 variant
  • both vaccines were 33% effective against symptomatic disease from B.1.617.2, 3 weeks after the first dose compared to around 50% effectiveness against the B.1.1.7 variant

The analysis included data for all age groups from 5 April to cover the period since the B.1.617.2 variant emerged. It included 1,054 people confirmed as having the B.1.617.2 variant through genomic sequencing, including participants of several ethnicities. Data published on Thursday 20 May for vaccine effectiveness covered the period since December for those aged over 65.

The difference in effectiveness between the vaccines after 2 doses may be explained by the fact that rollout of second doses of AstraZeneca was later than for the Pfizer-BioNTech vaccine, and other data on antibody profiles show it takes longer to reach maximum effectiveness with the AstraZeneca vaccine.

As with other variants, even higher levels of effectiveness are expected against hospitalisation and death. There are currently insufficient cases and follow-up periods to estimate vaccine effectiveness against severe outcomes from the B.1.617.2 variant. PHE will continue to evaluate this over the coming weeks.

Health and Social Care Secretary Matt Hancock said: This new evidence is groundbreaking – and proves just how valuable our COVID-19 vaccination programme is in protecting the people we love.

“We can now be confident that over 20 million people – more than 1 in 3 – have significant protection against this new variant, and that number is growing by the hundreds of thousands every single day as more and more people get that vital second dose. I want to thank the scientists and clinicians who have been working around the clock to produce this research.

“It’s clear how important the second dose is to secure the strongest possible protection against COVID-19 and its variants – and I urge everyone to book in their jab when offered.”

Dr Mary Ramsay, Head of Immunisation at PHE, said: “This study provides reassurance that 2 doses of either vaccine offer high levels of protection against symptomatic disease from the B.1.617.2 variant.

“We expect the vaccines to be even more effective at preventing hospitalisation and death, so it is vital to get both doses to gain maximum protection against all existing and emerging variants.”

Minister for COVID-19 Vaccine Deployment Nadhim Zahawi said: Almost every day we get more and more encouraging evidence about the difference our COVID-19 vaccines are making to people’s lives – with 13,000 lives saved and 39,100 hospitalisations prevented overall.

“Today’s data is astounding and a true reflection of just how important it is to get both your jabs when offered.

“I encourage all those offered an appointment to get their jab booked in as soon as possible and take full advantage of the high levels of protection the vaccines bring.”