Slightly raised mortality during hot week

© CBS / Alrik Swagerman
During the national heat wave in week 33 (from 10 to 16 August inclusive), there were an estimated 3,100 deaths in the Netherlands. This is over 400 more than in the previous weeks, when there was relatively low mortality. The excess deaths in week 33 are linked to the strong heat. There were relatively few confirmed COVID-19 cases. This is reported by Statistics Netherlands (CBS) in reply to media inquiries and based on provisional weekly mortality figures.
There was an official heat wave from 5 to 16 August inclusive, lasting a relatively long time (13 days) and including nine tropical days.

First clear increase since peak of additional deaths during pandemic

The excess mortality during the heat wave followed 13 weeks of relatively low mortality. Prior to this, mortality was elevated for nine weeks on account of the coronavirus epidemic. In weeks 11 to 19 of 2020, the estimated number of deaths in excess of the average during a similar-length period without a coronavirus pandemic stood at almost 9 thousand.
For week 33 and as at 18 August, the municipal health services (GGD) reported 15 confirmed COVID-19 deaths to the National Institute for Public Health and the Environment (RIVM). This means the excess mortality in week 33 is almost entirely due to the higher maximum temperatures.

Deaths registered weekly
 201720182019*2020*2020 (verwachting)
13568334330623102
23637335932623364
33487336431523154
43626332231793045
53574340331393161
63446351331833193
73417366032543198
83328369132202958
93152393730653096
103054409231723103
1128433733322532163052
1227783430304336123093
1328503225301344583114
1427643040289850843114
1528102860290249762908
1627132760303642993009
1727782663295639042925
1827692645280633782978
1928022641277229812932
2028012606282127723049
2127722674287327682809
2227012776273027242821
2326242679273426812860
2426432557264726912806
2526272601269226902891
2626912619283626593062
2726972726272526332835
2825202671276126082855
2926742704258625172848
3025712767300626662835
3125102760273126332944
3226572745262926093102
3325402605261331043114
34254526122617
35257625272783
36257026132553
37270725392642
38271527062580
39266926962751
40264128062717
41276327602912
42270627392879
43267626712867
44272628152856
45279727983015
46291627613060
47291728593023
48288629073045
49302729683018
50321830173161
51307930413253
52318729013028
* provisional figures Data reported for the 2020 week 33 are estimates.

More deaths as temperature rises

There were two official heat waves in 2019: from 22 through 27 July and from 23 July through 28 August. The first one was characterised by the highest maximum temperatures ever recorded in the Netherlands; almost 400 more people died than during an average summer week.
Previous research by CBS and the Netherlands Interdisciplinary Demographic Institute (NIDI) showed a correlation between higher temperatures and increased death rates. In July 2006, during one of the longest and most intense heat waves in at least 100 years, there were an additional estimated one thousand deaths compared to an average month of July. Over the past few years, this correlation appears to have become less obvious. The heat waves in 2018 barely caused any excess mortality. This may be related to the elevated mortality earlier in the year, which was linked to the particularly severe winter with flu epidemic.

Additional deaths mainly among people over 80

Excess deaths due to heat waves occur mainly among the population aged 80 years and over. This is also evident from the most recent heat wave. The estimated number of excess deaths in this age group was 300, similar to the heat wave last year.

More details next Friday

The mortality figures on week 33 presented here are estimates based on 85 percent of the death certificates as received by CBS. CBS will publish more detailed data on week 33 mortality on Friday 28 August. The data will be more complete by then and CBS will be able to provide a more accurate picture of mortality, also among long-term care users, by age group and by region.

Sources