In defiance of NHS advice, it has been revealed that hundreds of GPs are administering second Covid jabs just three weeks after the first.

The rollout of second doses up to nine weeks earlier than official guidance has triggered concerns over a postcode lottery in access to protection against coronavirus.

The Guardian newspaper has reported that GP vaccinators, high street pharmacies and some mass vaccination centres and pop-up jab clinics in different parts of England have taken the decision to offer second doses of the Pfizer/BioNTech jab after three weeks and of the Oxford/AstraZeneca vaccine after four weeks.

Doctors say their ‘pragmatic’ policy of shorter gaps between doses is boosting the immunisation drive ahead of 19 July, ensuring vaccines are not wasted, especially amid the spread of the Delta variant.

The Joint Committee on Vaccination and Immunisation has warned that people who were double vaccinated sooner than the rules allowed could end up being less protected against coronavirus.

Wei Shen Lim, the chair of Covid-19 immunisation at the JCVI, said: “The JCVI advises that preferably the second dose of currently approved Covid-19 vaccines should be given eight to 12 weeks after the first dose. The latest evidence indicates that a longer dose interval of eight to 12 weeks is likely to provide higher levels of protection than a shorter dose interval of three to four weeks.”

Evidence is also emerging that under-18s in some parts of London have already starting receiving their first doses even though the NHS has not yet given the green light for that age group to be jabbed.