How are we doing? The number of new cases per day remains high. It’s possible that incidence is rising more slowly in recent days, but it’s too early to tell. If we are starting to suppress the virus again, take this as encouragement to maintain and redouble our efforts. 1/7
It’s important to look at Dublin separately. This is daily incidence per 100,000 population for Dublin, Kildare-Laois-Offaly, and the remaining 22 counties. If every county had an incidence of 5 per 100,000, it would translate into about 250 cases a day across the country 2/7
Incidence remains high in Dublin, and is rising in the rest of the country. If we look at 14-day cumulative incidence for individual counties of interest, we can see high incidence in Dublin, and the recent rapid increase in Donegal 3/7
While we tend to focus on counties where incidence is increasing, it’s worth looking at counties where recent increases in incidence have been brought under control, such as Limerick, Tipperary, Leitrim, Kildare, Laois or Offaly 4/7
The first line of defence is us, limiting our discretionary social contacts and adhering to public health guidance, along with careful case management and outbreak control by public health departments. Formal public health restrictions are not inevitable, but may be necessary 5/7
We know we can do this. It’s hard, but limit discretionary social contacts and mixing between households. Get outdoors. Self-isolate if symptomatic, get tested, restrict our movements when required. #holdfirm on hand hygiene, physical distancing, and face coverings. 6/7
Sincerest thanks to colleagues in @hpscirleand and public health departments who provide, in near-real-time seven days a week, the surveillance data on which these analyses and the overall strategy policy decisions are based 7/7
Omicron will be a very significant challenge, but we are acting early, quickly and comprehensively. If we take a booster vaccine when offered, significantly limit contacts, mitigate risk, self-isolate if symptomatic and restrict movements if a contact, we can get through it. 1/22
The purpose of the formal restrictions is to significantly reduce risky social contact, the opportunity for the virus to transmit; they are to reinforce a call to all of us to prioritise our socializing over the coming weeks to a small group of people who matter most to us. 2/22
We already have, by reducing our contacts and adherence to basic public health measures, begun to bring infections and hospitalisations down after a significant surge of the delta variant in early November. This was difficult, but we did it together. 3/22
Let’s think and act positively. We can, with collective action, control transmission of SARS-CoV-2 again, and relieve the pressure of COVID-19 on our healthcare system. The effective reproduction number is currently estimated at around 1.2 1/12
If we can reduce our close social contacts by 30%, and/or mitigate the risks of those social contacts by 30%, we will have done enough to see the level of infection, case numbers and ultimately hospitalisations decline. 2/12
The more we prioritize and limit our social contacts, and mitigate those risks, the faster things will improve. The rising numbers of people in hospital and ICU are an urgent call to action. 3/12
The latest modelling of SARS-CoV-2 infection in Ireland shows that we urgently need to reduce transmission if we are to avoid further dangerous increases in cases and hospitalisations. Stay home with symptoms, limit contacts, use basic mitigations. 1/20
The current surge in disease began soon after the relaxation of measures on 20 Sept 2021, and accelerated from 22 Oct 2021 through the mid-term break. The increase in effective social contact is the primary driver, along with waning vaccine immunity. 2/20
Vaccines are very effective, but over time the immune defence against simple infection wanes. Fortunately, protection from severe disease is well maintained. The waning immunity means that increasing social contact causes a large and increasing force of infection. 3/20
Why are SARS-Cov-2 infections increasing in Ireland? It’s complex, but most likely a mix of increased mobility and social contact since late September, slippage on transmission prevention measures, and more social mixing indoors. 1/16
We had high but stable levels of infection through September 2021, but this was created by a very dynamic and delicate balance between increasing vaccine protection suppressing the virus, and increasing social contact creating opportunities for the virus to spread. 2/16
We started at a disadvantage compared to most of Western Europe. We were hit by a very large wave of delta infections in July, with most of the population under 50 not yet vaccinated, driving daily cases from 300 to 1800 per day between June and August. 3/16
There is no evidence that the reopening of schools has led to an increase in transmission or levels of infection amongst school-going children or more widely across the population. 1/14
The level of infection in children and adolescents had increased in the course of the summer as the delta variant increased the rate of transmission. 2/14
This had stabilized at a high level in children aged 12 and under, and decreased markedly in 13-18 year olds, as vaccination reduced incidence in adults and adolescents, and began to reduce the probability of children becoming infected. 3/14
A lot of commentary saying that most or all schoolchildren will be infected with SARS-CoV-2 in the coming months, based on an uncritical reading of this modelling study. It is highly unlikely that the scenario modelled will happen in the real world. 1/12
First, it’s not plausible. In the 12 weeks after primary schools reopened in March 2021 we detected 5,279 cases in children aged 5-12 years, or just under 1% of the population. The vast majority of these infections were transmitted in the community, not in school. 2/12
Even if delta is 50% more transmissible than alpha, it’s a long way from 1% of the population to 50-75% of the population becoming infected in 12 weeks; note also that most transmission was in the community, and the majority of the community is now vaccinated. 3/12