While no cases of the variant have yet been identified in Jersey, Islanders who received their first dose during phase one of the vaccination roll-out will now be offered their second between five to seven weeks later. Those who received their first jab more than five weeks ago will be contacted within the next few days for a follow-up appointment.
The original timescale for second doses was between four and 12 weeks.
The Joint Committee on Vaccination and Immunisation has updated its guidance to protect against the rising number of cases of the Indian variant.
Head of the Covid-19 vaccination programme Becky Sherrington said: 'Throughout our vaccination programme, we have always followed the latest advice issued from the scientific experts at the JCVI, and we are incredibly grateful for their continued guidance.
'The vaccination programme continues to be a vital element of protection from Covid and we are doing everything we can to vaccinate quickly to ensure we continue to keep Jersey safe. We have implemented our programme at record pace to get on top of Covid-19.'
She added that those under 50 will continue to be offered their first vaccination according to the timeline published last week.
'I would like to reassure Islanders under the age of 50 years old that the new changes to our schedule will not affect the dates we published at the end of last week, and we are still on track to have offered two doses of the vaccine to all eligible Islanders by mid-August,' she said.
Bookings for those aged between 30 and 35 opened on Friday, while those aged between 25 and 29 are due to be eligible for their first vaccination on Saturday 5 June. Appointments for those aged between 18 and 24 will begin on Saturday 19 June.
Deputy medical officer of health Dr Ivan Muscat said: 'While there is no current evidence to show this variant has a greater impact on severity of disease, it is more transmissible and seems to be infecting more young people.
'However, severity of Covid-19 is greater with increasing age, and two doses of the vaccine offer the best protection against this new variant. The doubling time in the UK appears to be about seven days and the speed of spread of this variant, which is now noted across the UK, requires us to work quickly to ensure the appropriate action is being taken as a safeguard for Jersey.
'While there is no evidence of the B1.617.1 variant in the Island, we continue to follow the advice of the JCVI to ensure our vaccination programme is aligned with the UK and we are giving the best protection to Islanders.'
By Wednesday 12 May, a total of 84,574 vaccine doses had been administered in Jersey.