Mortality in times of corona

Up to and including week 10 (ending 8 March) of this year, average mortality stood at 3,136 per week. It subsequently rose to reach its highest level in week 14 with 5,080 deaths. As of week 20, mortality is below the level considered normal for this time of year. It is a commonly known fact that periods of increased mortality are often followed by periods of low mortality; the latter is also known as undermortality.
However, the undermortality does not mean that there have not been any deaths related to COVID-19. In week 21, the number of deaths from COVID-19 as reported to RIVM (as at Thursday, 28 May 2020) stood at 104. The final number may turn out even higher, as not all COVID-19 patients are tested.
With a total of 36 thousand deaths over weeks 11 through 19, there were almost 9 thousand more deaths than normal, representing 32 percent excess mortality.

53 percent excess mortality among long-term care users

In the period week 11 to 19 inclusive, there were more than 15 thousand deaths among people receiving long-term care under the Wlz Act. This is an estimated 5 thousand more deaths than the expected mortality in this group under normal circumstances. Mortality among the rest of the population (over 17 million people) stood at almost 21 thousand in this period. This is around 3,500 or 20 percent more deaths than expected.

Relatively the highest excess mortality among the 75 to 89-year-olds

Relatively the highest excess mortality on account of the COVID-19 epidemic was recorded among the population aged 75 to 89 years. The excess mortality in this age group amounted to 42 percent on average. Although there was excess mortality among the over-90s as well, this was relatively lower than among 75 to 89-year-olds. In the age group 50 to 54 years, mortality was also relative higher than among the 60 to 64-year-olds (27 percent versus 18 percent).

Higher excess mortality among men

In absolute numbers, there were slightly more deaths among men than among women during the COVID-19 epidemic: 18.2 thousand against 17.7 thousand. This is unlike previous weeks and years, when there were slightly more deaths among women. In relative terms as well, mortality was higher among men in weeks 11-19 of this year. It was 37 percent higher than expected among men against 28 percent among women for this period had there not been a COVID-19 epidemic. Mortality has been relatively higher throughout among men than among women across all age groups.

Regional mortality distribution

Throughout the COVID-19 epidemic, relatively more excess mortality was recorded in the eastern part of Noord-Brabant, in Limburg and around the city of Zwolle. The municipality of Uden had altogether 178 deaths over weeks 11 to 19 inclusive; this is just over 3 times as many as during the weeks before the epidemic. Other municipalities with at least 2.5 times more deaths than normal during the coronavirus epidemic included Heerde, Meierijstad, Boekel, Bernheze, Peel en Maas, Zwartewaterland and Nunspeet.

Elevated mortality during the coronavirus epidemic

The elevated mortality during weeks 11-19 inclusive coincides with the beginning of the COVID-19 epidemic in the Netherlands. The first confirmed COVID-19 patient in the Netherlands was reported on 27 February 2020. The first death involving COVID-19 was reported on 6 March 2020. The COVID-19 outbreak was declared a pandemic by the World Health Organization (WHO) on 11 March 2020.

For the time being, this is the last news release reporting weekly mortality figures. The StatLine dataset and datasets under additional statistical services will continue to be updated on a weekly basis. The latest figures can also be found on the page ‘How many deaths are registered per week?’

Data sources for CBS and RIVM

CBS receives mortality data on a daily basis from municipal registers. This is before it receives any information on the causes of these deaths. CBS receives such information by way of the death cause certificates which are completed by the physician who attended the deceased. The publication of data from death cause certificates is normally scheduled for Q3 2020, but CBS will make every effort to release this information at an earlier stage.
RIVM receives data on confirmed COVID-19 deaths from municipal health services (GGD) around the country on a daily basis. Since not all COVID-19 patients are tested, the actual number of COVID-19-related deaths in the Netherlands is expected to turn out higher. A more complete picture emerges by looking at the total weekly number of deaths as based on the data received by CBS, regardless of the cause of death.

Estimates based on death certificates received so far

In general, some time elapses between the actual date of death and the moment when this data reaches CBS. Death certificates are collected weekly on Thursdays. Usually, mortality data collected on Thursday include slightly over 80 percent of all deaths over the previous week. This information provides an indication of the number of deaths that can be expected for that week.
Based on the data obtained over weeks 12 through 20, death certificates are currently being received sooner than usual (as the number of certificates that was received after one week turned out to cover 85 percent of all deaths) with the exception of weeks with public holidays. The estimate for week 21 is based on the assumption that for this week as well, 85 percent has been received. As the percentage is uncertain, the actual number of deaths in week 21 may be higher or lower as a result.