Table 1 Pros and cons for different delivery strategies for RTS,S malaria vaccine

1.1. Age-based delivery through the routine EPI using 4-dose schedule

• Delivery through a well-known and established system and opportunity to strengthen RI

• Caregivers and HCWs may be more familiar with this strategy

• Comparatively less resource-intensive than a campaign style delivery

• High drop-out rate between doses

• Relies on well-functioning EPI and health delivery system to achieve good coverages

• Potential challenges with 4th dose coverage

1.2. Age-based delivery through the EPI using 4-dose schedule with timed/seasonal PIRIs/catch-up (before the high transmission season)

• Provides opportunity to catch up on other vaccines or interventions

• Has the potential to reduce dropout rates with good 4th dose coverage compared to “regular” routine delivery

• Need for resources to sustain PIRIs

• *other potential challenges as above*

2.0. Seasonally-timed doses through campaign style delivery

• Has the potential to reach high coverage for all doses

• Leverages the period of high vaccine efficacy vs. high malaria transmission and thus provides greater protective efficacy

• May be suitable for specific populations (difficult to reach with poor health service delivery)

• Resource intensive

• May disrupt provision of other essential health services if not properly integrated and planned (vaccination campaigns and SMC)

3.1. Hybrid with primary 3 doses delivered through the routine EPI (age-based) with the annual doses (seasonal boost) given through a vaccination campaign before the high transmission season

• Primary doses delivered through an established platform

• Timed annual doses before the high malaria transmission doses for children who have completed primary series provides greater protective efficacy

• Potential of poor coverage of primary doses if EPI delivery system is suboptimal

• Vaccination campaign may require sustainable financing

• Variable interval between 3rd and 4th dose vs. current guidance

3.2. Hybrid – with Primary 3 doses delivered through the routine EPI (age-based) with the annual doses (seasonal boost) given through a media campaign/intensified communication (using routine EPI delivery) before the high transmission season

• Advantages mainly same as above in addition to providing the opportunity to optimize delivery with other child health interventions through the media campaigns

• Need for sustainable funding to ensure effective community mobilization through media campaigns

• May not be the best strategy for difficult to reach populations (will require extensive outreach services, if this planned to be HF-based)

• May result in low coverages and drop-out if media campaigns are not effective