BACKGROUND: Measles causes significant childhood morbidity in Nigeria. Routine immunization (RI) coverage is around 40% country-wide, with very high levels of spatial heterogeneity (3-86%), with supplemental immunization activities (SIAs) at 2-year or 3-year intervals. We investigated cost savings and burden reduction that could be achieved by adjusting the inter-campaign interval by region. METHODS: We modeled 81 scenarios; permuting SIA calendars of every one, two, or three years in each of four regions of Nigeria (North-west, North-central, North-east, and South). We used an agent-based disease transmission model to estimate the number of measles cases and ingredients-based cost models to estimate RI and SIA costs for each scenario over a 10 year period. RESULTS: Decreasing SIAs to every three years in the North-central and South (regions of above national-average RI coverage) while increasing to every year in either the North-east or North-west (regions of below national-average RI coverage) would avert measles cases (0.4 or 1.4 million, respectively), and save vaccination costs (save $19.4 or $5.4 million, respectively), compared to a base-case of national SIAs every two years. Decreasing SIA frequency to every three years in the South while increasing to every year in the just the North-west, or in all Northern regions would prevent more cases (2.1 or 5.0 million, respectively), but would increase vaccination costs (add $3.5 million or $34.6 million, respectively), for $1.65 or $6.99 per case averted, respectively. CONCLUSIONS: Our modeling shows how increasing SIA frequency in Northern regions, where RI is low and birth rates are high, while decreasing frequency in the South of Nigeria would reduce the number of measles cases with relatively little or no increase in vaccination costs. A national vaccination strategy that incorporates regional SIA targeting in contexts with a high level of sub-national variation would lead to improved health outcomes and/or lower costs.
BACKGROUND: Measles causes significant childhood morbidity in Nigeria. Routine immunization (RI) coverage is around 40% country-wide, with very high levels of spatial heterogeneity (3-86%), with supplemental immunization activities (SIAs) at 2-year or 3-year intervals. We investigated cost savings and burden reduction that could be achieved by adjusting the inter-campaign interval by region. METHODS: We modeled 81 scenarios; permuting SIA calendars of every one, two, or three years in each of four regions of Nigeria (North-west, North-central, North-east, and South). We used an agent-based disease transmission model to estimate the number of measles cases and ingredients-based cost models to estimate RI and SIA costs for each scenario over a 10 year period. RESULTS: Decreasing SIAs to every three years in the North-central and South (regions of above national-average RI coverage) while increasing to every year in either the North-east or North-west (regions of below national-average RI coverage) would avert measles cases (0.4 or 1.4 million, respectively), and save vaccination costs (save $19.4 or $5.4 million, respectively), compared to a base-case of national SIAs every two years. Decreasing SIA frequency to every three years in the South while increasing to every year in the just the North-west, or in all Northern regions would prevent more cases (2.1 or 5.0 million, respectively), but would increase vaccination costs (add $3.5 million or $34.6 million, respectively), for $1.65 or $6.99 per case averted, respectively. CONCLUSIONS: Our modeling shows how increasing SIA frequency in Northern regions, where RI is low and birth rates are high, while decreasing frequency in the South of Nigeria would reduce the number of measles cases with relatively little or no increase in vaccination costs. A national vaccination strategy that incorporates regional SIA targeting in contexts with a high level of sub-national variation would lead to improved health outcomes and/or lower costs.
Authors: C Edson Utazi; John Wagai; Oliver Pannell; Felicity T Cutts; Dale A Rhoda; Matthew J Ferrari; Boubacar Dieng; Joseph Oteri; M Carolina Danovaro-Holliday; Adeyemi Adeniran; Andrew J Tatem Journal: Vaccine Date: 2020-02-29 Impact factor: 3.641
Authors: Christian E Gunning; Lawrence Mwananyanda; William B MacLeod; Magdalene Mwale; Donald M Thea; Rachel C Pieciak; Pejman Rohani; Christopher J Gill Journal: BMJ Open Date: 2020-12-31 Impact factor: 3.006
Authors: Katy Am Gaythorpe; Kaja Abbas; John Huber; Andromachi Karachaliou; Niket Thakkar; Matthew Ferrari; Michael L Jackson; Kevin McCarthy; T Alex Perkins; Caroline Trotter; Mark Jit; Kim Woodruff; Xiang Li; Susy Echeverria-Londono Journal: Elife Date: 2021-06-24 Impact factor: 8.140
Authors: F T Cutts; E Dansereau; M J Ferrari; M Hanson; K A McCarthy; C J E Metcalf; S Takahashi; A J Tatem; N Thakkar; S Truelove; E Utazi; A Wesolowski; A K Winter Journal: Vaccine Date: 2019-11-29 Impact factor: 3.641