Hospitals have received new guidelines on the precautions needed to ensure that people admitted for other illnesses do not catch Covid-19.
It recently emerged that around 213 patients who were in hospital for other ailments ended up getting Covid-19.
Meanwhile, the latest report on the underlying medical conditions of people with confirmed Covid-19 shows that chronic heart disease remains the most common illness.
A total of 25,627 confirmed cases of Covid-19 have been reported up to midnight July 11. Data on underlying medical conditions are available for 19,298 of these confirmed cases and 9,966 cases, or 51.6pc, reported to have an underlying medical condition.
Of the total cases with data available on underlying medical conditions, 22.4pc had one condition, 11.9pc had two and 9.1pc had three or more conditions.
The five most commonly reported conditions overall were chronic heart disease, chronic respiratory disease, hypertension, diabetes and chronic neurological disease.
The Irish Heart Foundation said that many patients with heart disease or those who have suffered a stroke are older and may also have a less robust immune system.
Also people's immune systems tend to weaken as they age. Many of these patients will also have multiple risk factors for cardiovascular disease including, smoking and diabetes.
"It is also possible that the effects of the virus may exacerbate or worsen your underlying condition.
"For example, if you have heart failure, the heart already struggles to pump blood round the body and deliver oxygen to the body. If you contract the coronavirus your heart may be under even more strain if you develop a severe lung infection, which can further reduce oxygen levels. Viruses like the coronavirus can lead to inflammation throughout the body," said a spokesperson.