Tetanus and Diphtheria Seroprotection among Children Younger Than 15 Years in Nigeria, 2018: Who Are the Unprotected Children?

Abstract

Serological surveys provide an objective biological measure of population immunity, and tetanus serological surveys can also assess vaccination coverage. We undertook a national assessment of immunity to tetanus and diphtheria among Nigerian children aged <15 years using stored specimens collected during the 2018 Nigeria HIV/AIDS Indicator and Impact Survey, a national cross-sectional household-based survey. We used a validated multiplex bead assay to test for tetanus and diphtheria toxoid-antibodies. In total, 31,456 specimens were tested. Overall, 70.9% and 84.3% of children aged <15 years had at least minimal seroprotection (≥0.01 IU/mL) against tetanus and diphtheria, respectively. Seroprotection was lowest in the north west and north east zones. Factors associated with increased tetanus seroprotection included living in the southern geopolitical zones, urban residence, and higher wealth quintiles (p < 0.001). Full seroprotection (≥0.1 IU/mL) was the same for tetanus (42.2%) and diphtheria (41.7%), while long-term seroprotection (≥1 IU/mL) was 15.1% for tetanus and 6.0% for diphtheria. Full- and long-term seroprotection were higher in boys compared to girls (p < 0.001). Achieving high infant vaccination coverage by targeting specific geographic areas and socio-economic groups and introducing tetanus and diphtheria booster doses in childhood and adolescence are needed to achieve lifelong protection against tetanus and diphtheria and prevent maternal and neonatal tetanus.

Inequality in Immunization: Holding on to Equity as We ‘Catch Up’

“…The Special Issue features research, reviews, and commentaries that span a range of immunization topics and populations. While there is an emphasis on childhood vaccinations [ 15 , 16 , 17 , 18 ]—exploring inequalities in DTP and measles-containing vaccine (MCV) coverage [ 19 , 20 , 21 , 22 , 23 ] and patterns of inequality in unvaccinated or zero-dose children [ 24 , 25 , 26 , 27 , 28 , 29 ]—contributions also cover inequalities in adult immunization [ 30 ], including protection of pregnant women and their newborns against tetanus [ 31 ] and COVID-19 vaccination [ 32 , 33 ].…”

“…An encouraging observation while putting together this Special Issue has been the use of a variety of data sources to assess immunization inequalities. Studies have made use of traditional sources of immunization data like administrative data [ 19 , 23 , 32 ] and population surveys [ 18 , 21 , 22 , 27 , 29 , 30 ] (including Demographic and Health Surveys and/or Multiple Indicator Cluster Surveys [ 15 , 20 , 31 ]), while several other studies explored the potential of novel sources such as geospatial data [ 24 , 25 ], electronic immunization registries [ 34 ], dialogues [ 16 ], country appraisals and reports [ 35 ], and funding proposals [ 26 ]. Three review studies relied on synthesis and structured analyses drawing from a multitude of existing studies [ 17 , 33 , 36 ].…”

“…As dimensions of inequality present themselves and intersect in dynamic ways, our modes of understanding must keep up. Several studies in this Special Issue examined multiple dimensions of immunization inequality [ 18 , 19 , 21 , 27 , 29 , 31 , 33 , 36 ], while others focused on specific dimensions, such as gender barriers [ 20 , 34 ] or socioeconomic status [ 15 , 30 , 32 ].…”

Diphtheria outbreak in Nigeria: what we know now

“…The majority of cases occurred in children between 2 and 14 years of age. Among the cases, a total of 22 deaths were recorded [ 5 , 6 ].…”

“…In July 2023, a total of 1,506 suspected cases of diphtheria were reported from 59 Local Government areas (LGAs) in 11 states of the country [ 6 ]. Kano (1,055), Yobe (232), Kaduna (85), Katsina (58), Bauchi (47) and Federal Capital Territory (FCT) (18) accounted for 99.3% of all suspected cases.…”