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. 2021 Apr 8;39(15):2165–2176. doi: 10.1016/j.vaccine.2021.02.037

Table 2.

Study assumptions.

Routine immunization assumption SARS-CoV-2 immunization assumption Comments
Vaccines WHO prequalified vaccines in multidose vial presentation given per WHO recommended schedule.14 SARS-CoV-2 vaccine in multidose vial presentation given as two doses, one month apart. Given that there are no licensed SARS-CoV-2 vaccines, dose assumptions rely on dose schedule of SARS-CoV-2 vaccine clinical trials in the United States to date, and the volume analyses use packaging volumes per dose of AstraZeneca/Oxford University SARS-CoV-2 vaccine characteristics produced by Serum Institute of India.
Packaging Tertiary packaging at the national level
Secondary packaging at all subnational levels
Tertiary packaging at national level
Secondary packaging at all subnational levels
National level vaccine volume analyses use total tertiary packaging volume required per dose (the unit for international transport), defined as the volume of the container holding cartons which contain vaccine vials divided by the total doses contained.
Subnational levels vaccine volume analysis use total secondary packaging volume required per dose, defined as the volume of cartons which contain vaccine vials divided by the total doses contained.
Storage temperature 2° to 8 °C 2° to 8 °C
Coverage 90% of target group 90% of target group
Target groups WHO recommended ages Chronic diseases (any age)
Persons ≥ 65 years
Healthcare workers
Adults with chronic disease and older adults are at increased risk for severe SARS-CoV-2 disease [7]. Health care workers are at increased risk for SARS-CoV-2 infection and disease [7].
Strategy Year round Four month mass vaccination campaign Once pandemic vaccines are available, there will be an imperative to deliver them expeditiously.
Wastage multidose vials 25% 3% Vaccine wastage is the doses that are lost or unused. Routine immunization inputs are from WHO guidance [25]. SARS-CoV-2 wastage are from assumptions provided by Gavi to countries [13].
Reserve stock 3 months at national level
1 month at district and regional levels
0.5 months at health facility level
No reserve stock Vaccine reserve stock are the excess supply in case of increased demand or stock-outs. Routine inputs are from WHO guidance while SARS-CoV-2 inputs assume high global demand and limited supply [12], [22], [26].
Resupply intervals 3 months at national, district, and regional levels
1 month at health facility level
Every month Three month supply interval is common for routine immunization in low resource settings [24], while the SARS-CoV-2 supply interval assumes high global demand and limited supply.
Vaccinators Nurse density per capita for WHO African Region countries multiplied by the simulated country population, the proportion of nurses providing immunization services, and estimates of absenteeism at baseline and during the SARS-CoV-2 pandemic Same as for routine Typically, persons delivering vaccines in the region are nurses, but not all nurses engage in the provision of immunization services. The estimates for nurses per capita are from WHO [18]. Estimates of percentage of nurses providing immunization services are from the Organisation for Economic Co-operation and Development [27]. Absenteeism estimates from observational data (baseline) and modelling data (SARS-CoV-2) from the United States [28], [29].