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We have won the right to enjoy the summer but things can still go wrong

Analysis: Research findings demonstrate the effectiveness of Covid-19 vaccines

Ireland currently has close to 30%  first-dose coverage of all adults, but needs to get this up over 40%  to make the success made possible by vaccination stick.   Photograph: Getty Images
Ireland currently has close to 30% first-dose coverage of all adults, but needs to get this up over 40% to make the success made possible by vaccination stick. Photograph: Getty Images

The faster-than-expected loosening of restrictions announced by the Government on Thursday contains dangers, none of them unmanageable.

The decisions being taken this week have to be seen in context. Ireland has had one of the longest and most stringent lockdowns in the world; we have more ground to make up on many countries. Large swathes of the economy have been shut for months, and need to be able to reopen soon if they are to survive.

A second factor is the overwhelming research findings of the past six months demonstrating the effectiveness of vaccines.

Everywhere across the world we have clear data showing that vaccines are reducing infections, hospitalisations and deaths, as well as cutting transmission of the virus.

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In Ireland cases in nursing homes and among healthcare workers – the first two cohorts to be inoculated – have plummeted thanks to the “vaccination effect”. Just one outbreak has been recorded in a nursing home in the past three weeks.

Over time it has become evident that vaccines are working, even in countries that have suffered a third wave of the disease.

France and the US, for example, struggled in March as the UK variant spread, yet cases increased more slowly among vaccinated age groups. These and other countries whose immunisation campaigns are speeding up appear to have turned their latest corner in the pandemic.

In Chile, which along with much of South America, is in the throes of a vicious third wave, serious illness is falling among the vaccinated.

Even Israel, the world leader in immunisation against Covid-19, saw cases surge among the young before a critical mass of vaccination was reached and the graph headed downwards.

Some vaccines appear to be working better than others, but the differences in effectiveness between them are far smaller than the difference in protection afforded by vaccination of any type versus no vaccination. Again in Chile, for example, a “vaccine effect” is evident notwithstanding doubts about the effectiveness of the Chinese vaccines being used there.

Vulnerable people

The thinking from countries such as Israel or Denmark suggests vaccination of all vulnerable people, including those aged over 50 or 55, is the minimum threshold for properly suppressing the disease.

Ireland currently has close to 30 per cent first-dose coverage of all adults, but needs to get this up over 40 per cent to make the success made possible by vaccination stick.

Success will be a transient uptick in cases as people move around and mix more; failure, according to the modelling by the National Public Health Emergency Team, could mean thousands of cases a day once more.

After months of uncertainty there now appears to be confidence around the supply of vaccines to the State for the coming months. The available supplies of each of the four authorised vaccines will be focused on different cohorts, thereby maximising the acceleration of rollout – 220,000 doses last week, 240,000 next week.

Things can still go wrong. Dr Tony Holohan was barely back at work this month before he was warning again about "anticipatory behaviour". There is a danger of people getting ahead of themselves through overmixing when they aren't protected by vaccines.

An example is the successful campaign to ease visiting restrictions in maternity hospitals for partners of pregnant women. Restrictions are being lifted, arguably only slightly ahead of time, despite the reservations of staff concerned over a lack of space for social distancing in cramped premises.

One of the reasons Chile suffered a big surge last winter was because messages about social distancing and washing hands went out the window as large-scale vaccination arrived. Just as in Ireland now, it was holiday season and the borders were reopened; many holidaymakers brought back new variants on their return.

And while the middle phase of vaccine rollout in Ireland will be about volume – getting as many staff to administer as many doses as quickly as possible – the later phase of vaccinating the young will also be important. These groups will be harder to convince and may need to be incentivised if herd immunity is to be reached.

New variants

Much ink has been spilled over new variants in recent months. The dominant UK variant is estimated to be 30-90 per cent more transmissible than previous strains of the virus. The wide range in this estimate makes it hard to say for certain what will happened with increased mixing. Britain’s experience suggests vaccines can outmatch the variant’s impact, perhaps after an initial blip.

Other risky variants have been found here in small numbers, but seem unlikely to gain a proper foothold in time before mass vaccination. The current situation in India is in some ways analogous to Ireland before Christmas – although a new variant may be contributing to the surge, the main driver seems to be over-mixing by people.

There will be bumps on the road. There is the rest of the world to vaccinate, an important consideration in the reopening of international travel.

From now on, though, any rise in cases has to be placed in a new context as the proportion of cases progressing to serious illness and death will be greatly reduced.

There will inevitably be challenges next winter, though hopefully nothing like last December and January.

For now we have won the right to enjoy the summer, and the hard-earned freedoms it will bring.