Should we worry about recent post vaccination deaths in Norway? Almost certainly not. When elderly people are vaccinated, sadly some of them die quite soon afterwards, probably coincidentally. This has happened at the beginning of the rollout of the Pfizer vaccine in Norway, and there will probably be more reports like this from around the world, from countries that are keeping post vaccination statistics. Frail elderly people are being prioritised for the vaccine, as they are the most at risk from Covid19. But they are also the most at risk from most causes of death, so some coincidental deaths (shortly after vaccination) will continue to occur.

As vaccines are rolled out around the world, there is some concern about experience in Norway, where a small number of elderly people died shortly after receiving the Pfizer vaccine. This report explains

While the Norwegian Medicines Agency is now investigating the deaths — estimated to be about 30 — the regulator and Australian authorities have been quick to play down any serious safety concerns.

“This group of people who had these adverse effects, and unfortunately some died, were very, very old and frail,” Professor Brendan Murphy, secretary of the Department of Health, told ABC News Breakfast.

“It’s not clear whether the vaccine — how directly related to the deaths it was.”

Interestingly, the probability of this happening had been foreshadowed before Christmas by Stuart McDonald, a UK actuary, on the BBC program How to vaccinate the world:

Stuart McDonald of the Institute and Faculty of Actuaries told the BBC programme How to Vaccinate the World: “The largest priority group is the group aged 80 plus, and the average person within that group is around age 85. Life expectancy is not particularly long at that age.”

He explained: “About one in 12 85-year-olds is likely to die in the next calendar year… and because of the way that mortality rates increase exponentially as age increases, it’s actually around one in 10 of the people vaccinated would be expected to die in the next year. “It’s a very large number – 365,000 people across the UK, which is actually about six out of 10 UK deaths.”

The figures suggest that around 1000 over-80s a day would be expected to die each day, even if coronavirus and the vaccine did not exist. This means there will likely be thousands of cases where people receive the vaccine before they die of unrelated ailments, giving rise to a potential glut of anecdotes spread via social media.

So what do we know about the Norwegian statistics? The Norwegian statistical agency monitoring this has said:

The reports do not provide a basis for revising the current recommendations regarding the use of the coronavirus vaccines. The benefits of administering the vaccine are expected to outweigh the risks.

The latest weekly reports says that up to 21 January 2021, there were 30 deaths “with a temporal relationship to vaccination”, out of a total of 63,000 vaccinations (according to Our World in Data, administered over approximately three weeks).  So assuming that those vaccinated were vaccinated approximately a week and a half ago, that is an annualised mortality rate for those vaccinated of 1575 per hundred thousand. Norway is prioritising residents of aged care homes and those over age 85, but there is no public information I can find as the exact age distribution of vaccine recipients. Looking at the Norwegian age specific mortality rates, those vaccinated have experienced approximately the mortality rate of 70-74 year olds over the period since they were vaccinated (averaged across men and women). So this is very plausibly the result of the expected death rates of those vaccinated (there will be some vaccinations of younger people – health workers, etc, but most will have been over 85 and/or in aged care homes).

In other words, these statistics are completely consistent with the Norwegian deaths reported “with a temporal relationship to vaccination” being completely unrelated to the vaccination. And WHO has confirmed this after a review:

The current reports do not suggest any unexpected or untoward increase in fatalities in frail, elderly individuals or any unusual characteristics of adverse events following administration of BNT162b2. Reports are in line with the expected, all-cause mortality rates and causes of death in the sub-population of frail, elderly individuals, and the available information does not confirm a contributory role for the vaccine in the reported fatal events. In view of this, the committee considers that the benefit-risk balance of BNT162b2 remains favourable in the elderly, and does not suggest any revision, at present, to the recommendations around the safety of this vaccine.

Links

I’ve been seeing references to the Israeli vaccination experience for a while – both positive and negative. This Nature article gives a good summary of what we do and don’t know so far, and from my careful read, there is not yet any evidence for whether the vaccine provides protection against transmission (rather than disease).

As countries worldwide roll out COVID-19 vaccines, researchers are eagerly watching for early signs that they are having an impact on the pandemic. Last week, researchers in Israel reported preliminary figures suggesting that people vaccinated there were about one-third less likely to test positive for SARS-CoV-2 than people who had not received a shot. But scientists say that population-wide effects of immunization will take time to become clear.

If vaccines are effective at preventing infections, then their indirect benefit — protecting unvaccinated people — will be visible only once enough people have been immunized, says Natalie Dean, a biostatistician at the University of Florida in Gainesville.

Israel will probably be the first country to see this kind of population-wide impact, say researchers. This is because it is using a high-efficacy vaccine and aiming for wide coverage with the explicit goal of achieving herd immunity, when enough people are immune to a virus for its spread to be controlled.

In some places, the first signs of indirect protection might emerge in specific groups who have been widely vaccinated, such as health-care and long-term-care workers and their families, says Dean.

But teasing apart the population-level effects of vaccines on a drop in COVID-19 cases from the impacts of other public-health interventions, such as social distancing and lockdowns, will be tricky. “Infectious diseases are very unpredictable — so you end up needing a lot of data to smooth out a lot of unpredictability,” says Dean.

If you would like a chance to be an armchair epidemiologist, join this discussion thread from Sci-Fi author Charlie Stross on what you would do if there was a Covid19 outbreak on a future Mars colony.

The question

You are the Mayor of Armstrong City, facing a variant SARS pandemic, and supplies and support are 15 months away. What do you do?

Alternatively: what are the unforeseen aspects of a SARS-type disease infiltrating such a colony?

And what are the long-term consequences—the aftermath—for architecture and administration of the Mars colony, assuming they’re willing to learn and don’t want it to happen again?

Discuss.

And a final link, this one more sobering (thanks Alex for drawing my attention to it) to an as yet un peer reviewed study in the UK of people post discharge from hospital after Covid19. The study followed up individuals discharged from hospital after receiving treatment for Covid19, and matched them with people discharged for other reasons.  They were over 3 times more likely to be readmitted to hospital and over 7 times more likely to die (12% of all of them died) than their matched control patients.

Of 47,780 individuals in hospital with COVID-19 over the study period, 29.4% were re-admitted and 12.3% died following discharge (Table 2). These events occurred at rates of 766 (CI: 753 to 779) readmissions and 320 (312 to 328) deaths per 1,000 person-years, which were 3.5 (3.4 to 3.6) and 7.7 (7.2 to 8.3) times greater, respectively, than those in matched controls.

This is a new disease, and it will definitely have long term consequences for the health of the whole population that we don’t yet understand. Another good reason to avoid getting it – if you are able to achieve immunity from vaccination that is definitely a lot less risky than catching the disease.

Life Glimpses

With Sydney having a small outbreak of Covid19 just before Christmas, face masks are finally compulsory here in most public indoor settings (particularly shops and public transport). As I expected, now that they are compulsory, the vast majority of people are wearing them (up from about 30% just before the rule changed) – we are a very law abiding country. And in this house, we had to buy some more – we’ve been using our reusable cloth ones for long enough that they probably need replacing to be fully effective.

It does seem strange to wear face mask outside on a Sydney ferry, but I’m happy with a bit of illogicality for an overall reduction in transmission across Sydney (and to be able to catch a ferry, which would be forbidden to me in so many countries that are in full lockdown right now).

Bit of beauty

This picture is of a sunset kayak on a lake south of Sydney. The picture is beautiful enough, but doesn’t do the whole experience justice. As we were kayaking back to the wharf in the full darkness (without a moon and with the clouds clearing) there was bioluminescent plankton in the water, and we could see the milky way in the sky above us. With light pollution in most of the world, I am rarely lucky enough to see the milky way, and I am so glad I got to see it again in such a beautiful place.