Table 2.
Percentage change* in model parameters due to the COVID-19 pandemic and the related measures.
| 1st lockdown | 1st relaxation | 2nd lockdown | 2nd relaxation | 3rd lockdown | |
|---|---|---|---|---|---|
| Mid Mar–Mid May 2020 | Mid May–Mid Oct 2020 | Mid Oct 2020–Mid Apr 2021 | Mid Apr–Sep 2021 | Oct 2021–Mar 2022 | |
| HBV testinga | −75% | −25% | −30% | −15% | −15%, −5% |
| HBV vaccinationb | −70% | −20% | −35% | −30% | −30%, −5% |
| Casual partners, low activityc | −15% | −15% | −10%, −5% | −10%, −5% | −10%, −5% |
| Casual partners, moderate activityc | −25% | −5% | −15%, −5% | −5%, 0 | −10%, −5% |
| Casual partners, high activityc | −25% | 0 | −15%, −5% | 0 | −5%, 0 |
| Formation main partnerships | −15% | 0 | −10%, −5% | 0 | −5%, 0 |
Percentage change in each parameter calculated compared to its value in 2019 (before the COVID-19 pandemic), as 100*(d-b)/b, where b and d are the values of the parameter before (b) and during (d) the pandemic. Values shown in bold were estimated from data; values not in bold were assumed, as no data were available.
Changes in hepatitis B virus (HBV) testing were based on data from the National Database of Sexual Health Centres in the Netherlands from January 2020 to June 2021 [2], [6], [15]. The reduction in the 2nd relaxation period was based on the reduction in May and June 2021; the reduction in the 3rd lockdown was assumed.
Changes in the number of HBV vaccinations were based on data from the National Hepatitis B Vaccination Programme for Risk Groups [1], [10] until September 2021.
Changes in sexual activity during the 1st lockdown and the 1st relaxation period were based on data from the first round of the “COVID-19, Sex, and Intimacy Survey” [7]. For the changes from October 2020 onwards, two scenarios are shown, assuming a smaller reduction than that until first relaxation period [8], [9].