In that 13-month period, the vaccinations against the coronavirus SARS-CoV-2 prevented an estimated 87,676 hospital admissions. Most of the prevented admissions were among people aged 60 years and older: 68,152. Fewer admissions were prevented in the younger age groups. However, even among people aged 12-49 years, about 7,568 hospital admissions were prevented during this time. 

In the same period, the NICE Foundation recorded 44,731 hospital admissions involving COVID-19. The number of hospital admissions that were prevented is twice the number of hospital admissions that actually occurred. 

Another benefit resulting from these prevented hospital admissions is the reduced pressure on the healthcare system in the Netherlands. A reduction in extra pressure on the healthcare system leads to fewer delays in care. Without vaccination, the number of hospital admissions may have increased to such an extent that even more measures would have been needed. Finally, vaccination made a significant contribution to preventing deaths due to COVID-19. Statistics Netherlands (CBS) and RIVM published research results on deaths and excess mortality earlier this year.

This is a conservative estimate. RIVM expects that vaccination most likely prevented even more hospital admissions. For example, this RIVM analysis does not include the indirect effects of vaccination, such as reduced transmission. Vaccinated people are less likely to infect others. As a result, fewer people became ill, including some who may otherwise have ended up in hospital.  

Analysis method

In its analysis, RIVM used data on the actual number of hospital admissions provided by the NICE Foundation, the estimated vaccine effectiveness per day, and the vaccination coverage for the basic series of COVID-19 vaccinations, the booster vaccination and the first repeat vaccination against COVID-19. Using these figures, RIVM estimated the number of hospital admissions prevented in the age groups of 12-49, 50-59, 60-69, 70-79 and 80+. Since 25 January 2022, hospitals have been registering whether newly admitted patients were admitted with or because of COVID-19. From that point on, people whose reason for admission was not COVID-19 were not included in the analysis. 

To determine vaccination coverage, RIVM used data from the CIMS vaccination registration system and data on vaccinations provided by GGD GHOR Nederland. Vaccine effectiveness was estimated based on linked data from the NICE Foundation and CIMS, by reviewing the vaccination status of patients combined with data on hospital admissions. 

RIVM looked at the period from 2 August 2021 to 30 August 2022. This period was selected because all adults in the Netherlands were invited to receive a basic series of COVID-19 vaccinations in early August 2021. The RIVM analysis took into account how long it takes for the vaccine to become effective after completing the basic series, as well as the time between exposure and hospital admission. For that reason, the analysis only included hospital admissions that occurred after 23 August 2021. This also contributes to a conservative estimate of the number of prevented hospital admissions.
Previous infections and underlying health conditions were not considered in this analysis of the number of hospital admissions prevented by COVID-19 vaccination. This is because that information is not available to RIVM at the level of individual patients. 

COVID-19 basic series, booster and first repeat vaccination

The COVID-19 vaccination campaign in the Netherlands started on 6 January 2021. From July 2021 on, everyone aged 12 years and older could be vaccinated against COVID-19. By early August 2021, more than 80% of people over 12 had completed the basic series and was therefore protected against serious illness and death due to the coronavirus SARS-CoV-2.  

New vaccination rounds were offered in December 2021 and March 2022 to maintain a sufficient level of protection. RIVM published various reports on the effectiveness of these vaccinations. The latest round of COVID-19 vaccinations started in September 2022 and was first offered to people aged 60 years and older, people under 60 who were also eligible for the flu vaccine, and care workers. By now, everyone aged 12 and older can be vaccinated with the updated COVID-19 vaccines. 

Scientific publication

RIVM will publish more research results, further information and a detailed description of the analysis later this year.