A new study from Public Health England (PHE) has found COVID-19 vaccine are as effective at preventing symptomatic disease in most people in clinical risk groups as the rest of the population.

The study included one million people in at-risk groups, with those included in the study having underlying health conditions and more severe forms of illness.

Conditions such as diabetes, severe asthma, chronic heart disease, chronic kidney disease, chronic liver disease, neurological disease and diseases or therapies that weaken the immune system have been associated with an increased risk of hospitalisation or death with COVID-19.

Overall, the study found vaccine effectiveness against symptomatic disease in at-risk groups is approximately 60% after one dose of either the AstraZeneca or Pfizer/BioNTech vaccine.

After two doses, vaccine effectiveness with the AZ vaccine jumps to 81% in people in at-risk groups, aged 16 to 64 years old.

In people over 65 years in an at-risk group, vaccine effectiveness with the Pfizer/BioNTech vaccine is 89% and 80% with the AZ jab.

On top of that, the study found that 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 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,” said Mary Ramsay, head of immunisation at PHE.

“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,” she added.