Implementation performance of routine insecticide-treated nets distribution through the health facilities in mainland Tanzania: 5 years (2018-2022) experience.

BACKGROUND: The distribution of insecticide-treated nets (ITNs) through health facilities helps increase and sustain access to ITNs, targeting biologically vulnerable populations. However, their effectiveness in terms of issuance rates has yet to be assessed over time in Tanzania. METHODS: Monthly DHIS-2 data on ITN distribution from health facilities were extracted from 6,790 facilities from January 2018 to December 2022. The Generalized Estimating Equation (GEE) was used to model the marginal performance trend over time for ANC and EPI separately. RESULTS: Across 5 years, ANC had an issuance rate of 83%, while EPI averaged 70%. Issuing started at 44% and 34% in 2018 and increased to 93% and 80% in 2022 for ANC and EPI, respectively. Over the 5-year average, the public facilities performed better for both ANC (88%) and EPI (76%) compared to private facilities (53%) and (42%), respectively. Dispensaries and hospitals performed better than health centres and clinics at ANC and EPI. Rural areas had higher issuance (72%) during ANC visits compared to urban areas (51%). Across epidemiological strata, ITN issuing rates during EPI activities were notably higher in high (79%) compared to low (54%) transmission epidemiological strata. CONCLUSIONS: By 2022, Tanzania had substantially improved the ITN issuance rates via ANC and EPI in all health facilities compared to 2018. However, gaps remain in EPI, private, and urban facilities; targeted efforts are needed to achieve higher ITN issuance rates. Future studies to explore the reasons for differences among the analysed variables will help understand additional characteristics of high-performing facilities.