Dr. Colm Henry:

On the testing of healthcare workers, we have some information that will inform how useful it might be in a residential care setting. A vast exercise was carried out on all residents and staff in nursing home settings. We know from the report presented to NPHET last week by Dr. Lorraine Doherty, clinical director of health protection, that there was a very low positive result for healthcare workers, in the order of 3% or 4%. It is likely that when there is a focus on healthcare workers in terms of protecting them, as well as staff, we will consider a range of measures, including infection prevention and control, hygiene, PPE and the screening of healthcare workers going into nursing homes. Testing will form one part of that. My assessment is based on the advice from Dr. Doherty. Testing will be focused rather than blanket, because blanket point-in-time testing yielded very little information apart from telling us that there was a very low prevalence of the virus at that point in time.

The Deputy's second question was regarding hydroxychloroquine, a drug used for other conditions. There have been some small studies done which to date do not show any direct benefit.

The current advice from the expert advisory group, in line with that in other countries, is that more research is needed before we demonstrate this is of any benefit in either the prevention or treatment of Covid-19. It is a drug that is not without side-effects, particularly cardiac side-effects. As such, we would not recommend it for prevention of Covid-19.

The third question the Deputy asked was on the salivary test. The current test we use for Covid-19 is a polymerase chain reaction, PCR, test which detects viral ribonucleic acid, RNA, in real time. It is very sensitive, not only to those who are actively sick but even those who are in a presymptomatic phase of two days. It picks up pieces of the viral RNA and obviously it correlates with their degree of infectivity. Other tests proposed include serological tests which look for antibodies. These are not so sensitive in the acute phase and tell us nothing about people's infectivity. We will carry out some so-called zero prevalence studies in this country where we will detect antibodies in two populations. We will, hopefully, get that study done in June. It will tell us something about the exposure of the Irish population in two random populations to the virus throughout this pandemic.

The Deputy asked about a direct provision centre. I will enunciate the same principles that I have enunciated, namely, that outbreak management is a function of public health and each situation is different. Our public health departments are trained and have experience in going into these settings, looking at the layout, congregation, isolation facilities and number of positive tests and giving specific advice along a given set of principles which do not apply in any blanket way across all healthcare settings. With regard to direct provision centres, in some centres there has been testing of everyone in the setting based on the layout of the particular centre and the number of positive tests. In others, not everyone has been tested, either because there has not been an outbreak or there has been a very small number of positive cases. We leave it to the public health departments which are managing these outbreaks to make those judgments on an individual basis.