A new study has confirmed the circulation of Covid-19 among Ireland’s population before the first official case was announced here on 29 February 2020.
It follows a study of blood donations between February and September 2020.
The first antibody positive donor samples were confirmed on 17 February 2020 – two weeks before the first official case.
Significantly higher antibody levels for Covid-19 were found in Dublin compared to the rest of the country.
The study is published in the Journal of Clinical Virology.
Meanwhile, the overall number of Covid-19 outbreaks reduced by 12 last week, according to new data from the Health Protection Surveillance Centre.
There were 139 outbreaks reported to last Saturday, down on the previous week.
There were 30 outbreaks reported in schools, 26 in residential institutions, ten in hospitals and ten in nursing homes.
As routine contact tracing ended in primary schools at the end of September, the outbreak figure for schools should be considered with this in mind.
An outbreak is two or more linked cases.
As of 8am, there were 532 people with Covid-19 being treated in hospitals around the country, down 11 on the same time yesterday.
Of these, 118 people are in ICUs with the virus.
The Department of Health notified a further 4,152 cases of Covid-19 yesterday.
Northern Ireland has today reported 1,819 new coronavirus infections and a further four deaths.
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The Health Service Executive is expected to set out its plans following the recommendation yesterday by the National Immunisation Advisory Committee that children aged five to 11 years be offered a Covid-19 vaccination.
Some of the stocks of vaccine are expected to arrive next week when the first doses could be administered.
NIAC has said the HSE should consider setting up separate child-friendly Covid-19 vaccination clinics, which it said could help minimise distress and reduce the likelihood of vaccination error by having adult and paediatric doses at the same venue.
People aged 50 to 59 are now eligible for a booster vaccine.
Two drop-in clinics in Dublin reached full capacity after queues formed from early this morning.
Separately, the Department of Health has said that EU Digital COVID Certificates for booster vaccines are not currently being issued in Ireland.
French President Emmanuel Macron has said that Digital Covid Certs will not be valid without the booster vaccine included after 15 January 2022.