AstraZeneca vaccine guidance

AstraZeneca vaccine guidance

The UK vaccination programme has been very successful, with over 34 million people vaccinated and more than 10,000 lives saved.

Recently there have been reports of an extremely rare but serious condition involving blood clots and unusual bleeding after AstraZeneca (AZ) vaccination. Some people with this condition have suffered life changing effects and some have died. These cases are being carefully reviewed but the risk factors for this condition are not yet clear.

Although this condition remains extremely rare there is a higher risk in people after the first dose of the AZ vaccine. To date and overall, just over 10 people develop this condition for every million doses of AZ vaccine given. This is seen more often in younger people and tends to occur between four days and four weeks following vaccination.

Similar conditions can also occur naturally, and clotting problems are a common complication of coronavirus (COVID-19) infection. An increased risk has not yet been seen after other COVID-19 vaccines in the UK.

On 7 May, the JCVI updated its guidance and now advises that all adults aged 30-39 without underlying health conditions should receive an alternative to the Oxford/AstraZeneca vaccine where available and only if this does not cause substantial delays in being vaccinated.

Adults aged 40 years or older, care home residents and adults of any age with underlying health conditions can still receive any of the available COVID-19 vaccines.

The JCVI continues to advise that it is preferable for healthy adults aged 18 to 29 to have a vaccine other then AstraZeneca.

Second doses

If you have already had a first dose of AZ vaccine without suffering this rare side effect you should complete the course. This includes people aged 18 to 39 years who are health and social care workers, unpaid carers and family members of those who are immunosuppressed. It is expected that the first dose of the vaccine will have given you some protection, particularly against severe disease.

Having the second dose will give you higher and longer lasting protection and tends to cause less of the common side effects (including short lived headache).

What to look out for after vaccination

Although serious side effects are very rare, if you experience any of the following from around four days to four weeks after vaccination you should seek medical advice urgently:

  • a new, severe headache which is not helped by usual painkillers or is getting worse
  • a headache which seems worse when lying down or bending over
  • an unusual headache that may be accompanied by:
    • blurred vision, nausea and vomiting
    • difficulty with your speech
    • weakness, drowsiness or seizures
  • new, unexplained pinprick bruising or bleeding
  • shortness of breath, chest pain, leg swelling or persistent abdominal pain.

For more information on COVID-19 vaccination and blood clotting, please visit the website

Operational guidance for health and care system leaders can be found here.