An interesting study by Lee et al. (2016) present alternative supply chain designs for Mozambique. Vaccine coverage rates had been well below 100% (e.g., in 2008, only 75% of one-year-old children were fully immunized with the third dose of diphtheria-tetanus-pertussis vaccine). Working closely with the Ministry of Health, UNICEF, and WHO, the research team used a new combination of computational simulation modeling, information systems, stakeholder engagement, and training to help evaluate the Mozambique supply chain and develop, evaluate, and ultimately introduce a new supply chain design. The new design raised vaccine availability (from 66% to 93% in Gaza; from 76% to 84% in Cabo Delgado) and reduced the logistics cost per dose administered (from $0.53 to $0.32 in Gaza; from $0.38 to $0.24 in Cabo Delgado) as compared to the multi-tiered system under the current expanded program on immunization. The alternative system also produced higher availability at lower costs after new vaccine introductions. Since reviewing scenarios modeling deliveries every two months in the north of Gaza, the provincial directorate has decided to pilot this approach diverging from decades of policies dictating monthly deliveries.
The three supply chain designs considered for Gaza are as follows. Figure (a) presents the original multitiered distribution system (G1), which has three levels below the national depot: province, district, and health center. The provincial store attempts to pick up vaccines from the national level quarterly using a 4 × 4 truck but is able to make additional trips as needed. The provincial level delivers vaccines to the 12 district stores monthly. Approximately 60% of health centers receive monthly deliveries from the district level via pickup truck or motorbike while the remaining health centers retrieve vaccines from the districts each month using public transportation.
Figure (b) presents the current implementation of alternative distribution system (G2) using transport loops in south that utilizes two distribution loops to deliver from the provincial level directly to health centers in the southern region of the province using district personnel for additional supervision. Due to long distances, difficult terrain, and small populations, two additional loops deliver vaccines from the provincial level to the four district stores in the northern region. Vaccines then move to the northern health centers by the same methods as in structure G1
Figure (c) shows potential implementation of alternative distribution system (G3) using transport loops throughout province. It expands the recently implemented alternative system to full coverage of all health centers throughout the province. In addition to the two existing delivery loops in the south, two distribution loops deliver vaccines monthly from the provincial level directly to health centers in the north
The authors consider two additional alternative scenarios: (i) A system with full delivery loop coverage, delivery to northern health centers every two months (G4); (ii) A system with full delivery look coverage, delivery to all health centers every two months (G5).
Vaccine availability and logistics cost per dose administered for Gaza scenarios are presented in the figure below. (Note: +RV + HPV + IPV + MSD indicates introductions of rotavirus (RV), human papillomavirus (HPV), inactivated polio (IPV), and a second dose of measles (MSD) vaccines.)
For Cabo Delgado the following supply chain designs were evaluated:
(a) The first design (C1) has three levels below the national depot: province, district, and health center. The provincial store receives vaccine shipments from the national level quarterly by plane but receives additional deliveries as needed. The provincial level delivers vaccines to the 17 district stores monthly. Approximately 60% of health centers receive monthly deliveries from the district level via pickup truck or motorbike while the remaining health centers retrieve vaccines from the districts each month using public transportation.
(b) The second design (C2) includes three loops delivering vaccines monthly from the provincial level directly to 52% of the health centers in the province. The remaining health centers are located in hard-to-reach peripheral areas and must retrieve their vaccines from the health centers located at the headquarters in their respective administrative districts, using motorbikes or public transportation. One district is not included in a loop and instead receives monthly deliveries from the provincial store via 4 × 4 truck
(c) The third design (C3) expands the existing three delivery loops to full coverage of all health centers throughout the province.
These design scenarios are presented in the following figure:
Two additional scenarios were also considered: (i) A system (C4) that alternates between reduced delivery and full delivery loop coverage each month, resulting in monthly deliveries from the provincial level to 52% of health centers. Peripheral health centers receive deliveries from the province every two months. (ii) Alternative system (C5), full delivery loop coverage, every two months throughout the province.
The following figure presents vaccine availability and logistics cost per dose administered for Cabo Delgado scenarios. (Note: +RV + HPV + IPV + MSD indicates introductions of rotavirus (RV), human papillomavirus (HPV), inactivated polio (IPV), and a second dose of measles (MSD) vaccines.)
Implementation
The Gaza provincial directorate plans to pilot this approach diverging from decades of policies dictating monthly deliveries. This pilot is complemented by new remote temperature monitoring technology for the cold chain, also being piloted in that province, to better guarantee the safety of the vaccines.
Source: Lee, B.Y., Haidari, L.A., Prosser, W., Connor, D.L., Bechtel, R., Dipuve, A., Kassim, H., Khanlawia, B. and Brown, S.T., 2016. Re-designing the Mozambique vaccine supply chain to improve access to vaccines. Vaccine, 34(41), pp.4998-5004.