Pockets of Dublin became Covid-19 'hotspots', according to new data, sparking calls for greater clarity about where clusters emerge.
Communities in north Dublin have been the worst affected parts of the country for coronavirus, figures from the Health Protection Surveillance Centre (HPSC) show.
Dublin North West and Dublin North have had the greatest number of infections and deaths, with communities in the south of the county reporting smaller figures.
Dublin is the county at the epicentre of the Covid-19 pandemic in Ireland, with the most deaths and cases to date.
The data, released to the Irish Independent this week, shows the variation in cases and deaths between the eight HSE Community Care Areas (CCAs) in Dublin.
Cork and Kildare are the counties with the highest level of infection outside of the capital. But there have been more cases in some specific community care areas in Dublin than in the entire county of Cork.
Dr Jack Lambert said the data points to a number of clusters that appeared in parts of north Dublin in March and April.
The infectious diseases consultant at the Mater Misericordiae Hospital in Dublin called for more detail to identify groups and areas vulnerable to a dangerous second wave of infection.
In the UK, data published by the Office for National Statistics shows the number of Covid-19 deaths in each postcode and area.
Dr Lambert said that while the CCA data was useful, postcode data should be used to analyse and inform the response.
"Nailing down and targeting the clusters would be a key preventative measure in preparing for a second wave," he said. "Instead of waiting for those clusters to reappear in the same places, steps should be taken now to target the groups or industries associated with them.
"There could be nursing homes or staff who work in meat plants, many of whom live in shared accommodation in some of the areas with a high number of infections.
"You will have businesses preparing to open up again and take staff back into offices, and data on where the clusters are could be used to inform how they do that safely.
"The numbers of new infections have been decreasing, but that is because we have been in lockdown.
"The key to all of this is clusters. As people start to gather in these hotspots again, there is a risk that the numbers will spike again if the embers of the fire are not extinguished."
The HPSC released the data after several requests, but declined to release data relating to postcodes in the Dublin area, which would give a clearer picture of exactly where clusters have appeared.
Initially, the HSE said the data could not be published due to issues over confidentiality.
A later statement, issued by the HSE last night, said the HPSC did not hold a "verifiable dataset broken down by the postcode of people who have lost their lives to Covid-19 for any area of the country".
Social Democrats co-leader Róisín Shorthall called for more detailed data to be published so that businesses and individuals can be properly informed as the country emerges out of lockdown.
"There is a huge amount of data being collected by the HPSC, but it's not necessarily being published," Ms Shorthall said.
"That's the way you keep the public with you and how you identify where high-risk areas are, or high-risk industries.
"On the basis of that, then decisions can be taken. There is no justification for keeping things secret. It's really important that there is absolute transparency about all of the data that relates to this issue and that decisions are taken on the basis of that data."
As of midnight on Monday, the highest number of Covid-19 cases was reported in Dublin North West, with 2,183 cases, followed closely by Dublin North, with 2,164 cases.
In relation to Covid-19 deaths, the highest number has been reported in Dublin North, with 125, followed by Dublin West, with 121 deaths.
By comparison, Cork has had 1,386 cases of Covid-19 to date.
Kildare is the county in third place with 1,381 cases, followed by Cavan (804), Meath (788) and Louth (748).
The least affected county is Leitrim, with 82 cases.
Community care cases and deaths in Dublin area
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