Twitter has partnered with the HSE to promote credible information on vaccinations.
Users who search for certain keywords will now get prompted to check out a dedicated page on the HSE's website.
Twitter said the link will appear at the top of search results ensuring it has high-visibility and prominence.
Karen White, the director of public policy for Twitter in Europe, said: "Twitter's main priority as a company is to protect the health of the public conversation on the platform - ensuring individuals can find information from authoritative sources like the HSE is a key part of that mission.
"We understand the importance of vaccines in preventing illness and disease and recognise the role that Twitter plays in disseminating important public health information.
"To this end, I'm delighted to launch this tool today in partnership with the HSE.
Dr Lucy Jessop, director of the National Immunisation Office at the HSE, said: "Our goal is to get the most accurate vaccine information out to the public to ensure people can make informed decisions around their health.
"We are delighted to work with Twitter on this innovative project and interact in a positive way with the wide network of users using this platform.
"The National Immunisation Office's websites are accredited by the WHO Vaccine Safety Network as credible sources of information for those who want to find out more."