People aged 65 and over in Suffolk and north Essex have been told there is "absolutely no need" to wait for a letter inviting them for a coronavirus vaccine amid postal delays.
Postal deliveries have been affected by delays in recent weeks, owing to heavy snowfall from Storm Darcy across East Anglia.
Several Royal Mail staff have also been self-isolating due to Covid-19 - including 36 workers from the Bury St Edmunds depot who were forced into quarantine earlier in February.
The delays have meant people across the region have not received the letter from the NHS inviting them to book a coronavirus jab online.
However, the Suffolk and North East Essex Integrated Care System, which is overseeing the vaccine rollout, has urged people over the age of 65 to book their jabs on the NHS website if they are yet to receive their first dose - even if they have not been contacted.
A spokesman said: "We’d remind everyone aged 65 and over that they can book in for their first dose of the Covid-19 vaccination by going online to the national website.
"There’s absolutely no need to wait for a letter from the NHS before booking your appointment.
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"We know that for some people, postal deliveries have been interrupted due to the recent bad weather and because of postal workers self-isolating.
"Everyone eligible to receive the vaccine is encouraged to make an appointment."
The government announced last weekend it had rolled out more than 15million coronavirus jabs among the most vulnerable in the population.
Ministers are hoping to have rolled out the vaccine to the rest of the population over the age of 50 by the end of April.
Figures released by NHS England earlier this week revealed the Suffolk and north-east Essex NHS area was in the top six nationally for people receiving their first Covid-19 jab, with more than a third of the population inoculated.
Just over 94% of over-80s, one of the most vulnerable groups, have now received their first jab in the region.
Andy Yacoub, chief executive of Healthwatch Suffolk, said the latest figures were "pretty good, all things considered" after a slow start to the rollout owing to supply issues.
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