A booster vaccination provides more protection against hospital admission than only completing the basic series of COVID-19 vaccinations: 97% compared to 83%. This means that the risk of hospital admission after a booster vaccination is 33 times lower compared to no COVID-19 vaccinations and 5 times lower compared to a completed basic series without a booster. 

The booster vaccination offers 98% protection against ICU admission, while the basic series offers 93% protection. The risk of ICU admission after a booster vaccination is 50 times lower compared to no COVID-19 vaccinations and 4 times lower compared to a completed basic series without a booster.

Delta variant

During this reporting period, most hospital admissions involving COVID-19 were caused by the Delta variant of the coronavirus SARS-CoV-2. Vaccine effectiveness between 1 December 2021 and 25 January 2022 is therefore mainly related to the Delta variant. It is not yet possible to estimate vaccine effectiveness against hospital admission in the Netherlands due to the Omicron variant. 

Sources

The analysis is based on NICE data on hospital admissions of patients with COVID-19 admitted until 25 January 2022. The data was enriched on 26 January 2022 with vaccination data from the COVID-19 Information and Monitoring System (CIMS). The method used to calculate vaccine effectiveness is explained in the report: Study: Effectiveness of COVID-19 vaccination against hospital and ICU admission in the Netherlands

Please note: raw data cannot be published due to its privacy-sensitive nature.