Those who have long-term health conditions, for example diabetes, asthma or heart disease should now come forward for their second booster.
the HSE said. People can book an appointment for a HSE vaccination clinic online or check with participating GPs and pharmacies.
Those aged over 50 or are pregnant for more than 16 weeks are also invited to book their next booster. Appointments are available from today and information on eligibility is available on the HSE website.
The Chief Clinical Officer of the HSE said people with long-term health conditions are at greater risk from serious illness from Covid-19 "Getting a second booster vaccine now will help protect these people, particularly as we come in to the autumn," Dr Colm Henry said. "We know immunity from Covid-19 vaccination and previous Covid-19 infection decreases over time so getting your booster when it's due will give you the best protection from serious illness, and increase immunity against infection from Covid-19," he added.