Last week, 242,961 positive COVID-19 tests were reported to RIVM*. That is an increase of 21% compared to the week before that.
The highest number of reported positive tests per 100,000 inhabitants was seen in the age group of 18-24 years old. The biggest increase in reported positive tests in the past week was seen among children and adolescents in the primary school (+131%) and secondary school (78%) age groups. Compared to other age groups, the number of people aged 60 years and older who tested positive for COVID-19 has been stable and low in recent weeks (Figure 1).
During the lockdown period, the booster vaccination campaign quickly gained momentum. Of the people aged 60 years and older who are currently eligible for the booster vaccination, about 90% have now received a booster vaccination. More than half of all people aged 18 years and older have now had their booster
Following the relaxed measures, the number of reported positive tests may continue rising sharply in the next few weeks. How the latest relaxed measures will affect the number of people who test positive for COVID-19 and on the number of subsequent new hospital admissions will become clear over the course of the upcoming weeks.
Figure 1: Number of reported positive tests per 100,000 inhabitants, by age group (6 December 2021 to 16 January 2022).
More than 685,000 people were tested by the Municipal Public Health Services (GGDs), 18% more than in the week before that. The percentage of positive COVID-19 tests rose to 36.8%.
One in five (20%) of people who came to the GGD for testing were confirming a positive self-test. 88% of these people who tested positive for COVID-19 on a self-test also received a positive test result from the GGD confirmation test. Half (47%) of all positive COVID-19 tests were after a positive self-test (based on available information).
The percentage of people who had a SARS-CoV-2 infection at least 2 months ago and are now infected again was 12%, staying about the same (13% last week, see graph in weekly update of Tuesday 11 January).
With the increase in cases involving the Omicron variant, the number of reinfections is rising sharply. In comparison, the Delta variant resulted in an average reinfection rate of 3% of the people who were tested.
The number of patients with COVID-19 admitted to hospital and ICU continued to decrease last week, due to the earlier lockdown measures. As a result, there is currently more room for regular care and delayed care again. In the past week (10 to 17 January 2022), 647 new patients with COVID-19 were admitted to hospital nursing wards (last week: 940, -31%), and 94 of those were admitted to ICU (last week: 146, -36%).
People currently hospitalised with COVID-19 may be infected with either the Delta variant or the Omicron variant.
Reproduction number R
The most recent reproduction number for SARS-CoV-2 (3 January 2022) was 1.16 (1.14 – 1.17). That is a decrease compared to the week before that (1.26 on 27 December 2021). That means that 100 people who had COVID-19 on 3 January 2022 will collectively infect another 116 new people.
Looking at the Omicron variant on its own, the reproduction number dropped from 1.63 on 27 December 2022 to 1.25 (1.24 – 1.28) on 3 January 2022. On 3 January 2022, the reproduction number for the Delta variant was 0.55 (0.50 – 0.61), also down compared to the week before that (0.78).