Polio outbreak among nomads in Chad: outbreak response and lessons learned

Abstract

Background: In response to the 2011 and 2012 polio epidemic in Chad, Chad's Ministry of Public Health, with support from Global Polio Eradication Initiative partners, took steps to increase vaccination coverage of nomadic children with targeted polio campaigns. This article describes the strategies we used to vaccinate nomads in 3 districts of Chad.

Methods: Our targeted interventions involved using mobile vaccination teams, recruiting local nomads to identify settlements, using social mobilization, and offering vaccinations to children, women, and animals.

Results: Vaccination coverage of nomadic children 0-59 months of age increased, particularly among those never before vaccinated against polio. These increases occurred mostly in the intervention districts of Dourbali, from 2956 to 8164 vaccinated children, and Kyabe, from 7319 to 15 868. The number of first-time vaccinated nomadic children also increased the most in these districts, from 60 to 131 in Dourbali and from 1302 to 2973 in Kyabe. Coverage in the Massaguet district was only 37.7%.

Conclusions: Our success was probably due to (1) appointment of staff to oversee implementation, (2) engagement of the national government and its partners, (3) participation of nomadic community leaders, (4) intersectoral collaboration between human and animal health services, and (5) flexibility and capacity of vaccinators to vaccinate when and where nomads were available.

Keywords: nomad health; polio vaccination; vaccination outreach strategies; vaccinations of mobile populations.

Figure 1.

Chad migration routes and Hadjer-Lamis vaccination points.

Figure 2.

Wild poliovirus cases among nomads and the general population in Chad, 2011–2012.

Figure 3.

Distribution of wild poliovirus cases among regions in Chad, 2011–2012.