Covid-19 continues to live up to its reputation as the virus that refuses to go away.
Cases, hospitalisations and ICU admissions are all increasing at present, and the number of deaths is also attracting attention.
Current trends point to a fresh, sixth wave in this pandemic, though no one is expecting it to inflict the level of harm seen in previous ones.
Most of the population is in large part protected through vaccination and booster doses. But at the margins Covid-19, even the milder Omicron variant, remains capable of inflicting significant damage on the most vulnerable.
It is difficult to be certain about the level of infection in the community at present because less testing and surveillance is being carried out. Yet the clear indications are that cases are rising, have been for some weeks and may continue doing so.
For example, the proportion of positive PCR tests has increased from 12.5 per cent to 19 per cent over the past fortnight. The number of tests carried out weekly has increased from 30,000 to 33,000.
The trend in cases has already translated into a rise in the number of people in hospital with the disease, up from a low of 167 at the end of May to 289 on Wednesday. That’s an increase of more than 75 per cent in less than two weeks.
The number of patients in intensive care units (ICU) is also rising, from a low of 18 in late May to 27 now. At least half of these hospital/ICU cases are people who were admitted for other reasons but are now testing positive.
Infectious diseases consultant Dr Eoghan de Barra says most of the cases he is coming across in Beaumont Hospital are incidental, so far at least. Where there are more cases in the community there will, inevitably, be more also in hospital.
So what is driving these increases?
We know that past surges in this pandemic were often sparked by increased social mixing together with the emergence of new, more transmissible variants. It seems likely the same factors are involved again this time, though the data is sketchy.
Monitoring tells us, for example, that many people are socialising and mingling at pre-pandemic levels. Over the past week, there have been mass gatherings at sports events, music festivals and even Dublin Airport that provide the perfect environment for super-spreading events.
In other countries — Portugal, for example — new subvariants of Omicron have been driving rises in cases, hospitalisations and deaths. According to official data, there is no evidence these new, more transmissible subvariants are making inroads here — but the level of genomic sequencing being carried out in Ireland, and which is needed in order to identify variants, is abysmally low.
In the UK, three new strains, BA.5, BA.4 and BA2.12.1, now account for nearly half of all sequenced cases. It wouldn’t be surprising, therefore, if these subvariants are circulating more than official figures suggest.
The new subvariants do not alter the calculus around Covid-19 that has prevailed since Omicron became dominant. They may be marginally more transmissible, and they may have a greater ability to re-infect people who had the virus in earlier waves, but there is no evidence they are more lethal.
Prior vaccination, or previous infection, continues to protect against serious illness. Where people are dying, this is because they are unvaccinated, or their vaccine protection has waned — this happens faster with older people — or their systems do not respond to vaccines and are not protected.
Last week, the Department of Health reported 77 Covid-19 deaths, enough to send Ireland into the world top 10 for mortality, as measured by Our World in Data. However, most of these deaths had happened earlier in the year — almost 70 per cent occurred in April or earlier — so the current actual death rate here is lower than appears in international comparisons.
The flip-side of this is that there were more deaths in the spring than we knew about at the time — more than 300 occurred in March and April. The process for registering deaths is as slow now as it was at the start of the pandemic.
We could be doing more to reduce this death toll, by increasing the uptake of booster doses and making antiviral treatments more widely available. Current policy, and public disposition, seem to favour waiting until the autumn before ramping up the public health response again, but the virus may not allow us to tarry that long.