The Knowledge Hub

Investments in polio eradication in Africa improved overall immunization systems and increased coverage of routine vaccinations

A systematic review of 8 African countries that had wild polio virus transmission and significant polio eradication activities found evidence that the huge investments made in polio have strengthened capacity in almost all aspects of the overall immunization systems, especially in the areas of microplanning, service delivery, capacity-building (especially supportive supervision and on-the-job training), and program management. This led to substantial increases in coverage of other routine vaccinations – BCG, DPT, measles – in all 8 countries over a 25-year period (1989-2014), including a more than a 3-fold increase in DPT3 coverage in 2 countries and a more than a 2-fold increase in 3 other countries.

Anya BPM, Moturi E, Aschalew T et al.. 2016. Contribution of polio eradication initiative to strengthening routine immunization: lessons learnt in the WHO African region. Vaccine. 34(43).

Integrating vitamin A supplementation during vaccine campaigns increased coverage and effectiveness for both interventions

In an effort to reach children with vitamin A deficiency in the African countries of Angola, Chad, Cote d’Ivoire, and Togo, vitamin A supplementation was administered during Polio vaccine campaigns. This led to a minimum coverage of 80% for vitamin A and 84% for polio vaccine in all of the immunization campaigns. During the second year of vitamin A integration into the polio vaccination campaign, coverage exceeded 90% for both vitamin A and polio vaccination in all four countries.

Chebab, E.T., et al.. 2016. Experience of integrating vitamin A supplementation into polio campaigns in the African Region.. Vaccine. 34(43).

Migration can increase measles risk for unvaccinated children

Researchers investigating the causes of a measles outbreak in Burkina Faso that occurred despite a recent mass vaccination campaign found that migration to and from Cote d’Ivoire was a major risk factor for children. Unvaccinated children who developed measles were 8.5x more likely to have recently traveled to Cote d’Ivoire than unvaccinated children who had not traveled across the border. Children returning to Burkina Faso after a period of time in Cote d’Ivoire were less likely to have been vaccinated due to low routine coverage of measles vaccines in Cote d’Ivoire. Conversely, unvaccinated children from Burkina Faso who traveled to Cote d’Ivoire and returned were more likely to be exposed to measles and thus had a higher rate of disease than children who never visited Cote d’Ivoire.

Yameogo, K.R., Perry, R.T., Yameogo, A., et al.. 2005. Migration as a risk factor for measles after a mass vaccination campaign, Burkina Faso, 2002. International Journal of Epidemiology. 34(3).

Pediatric pneumococcal or Hib meningitis surviviors had a higher likelihood for neuropsychological deficits

In a systematic literature review of studies in Africa, it was found that 25% of children who survived pneumococcal or Hib meningitis had neuropsychological deficits.

Ramakrishnan, M., Ulland, A.J., Steinhardt, L.C., et al. 2009. Sequelae due to bacterial meningitis among African children: a systematic literature review. BMC Medicine. 7(47).

Bacterial meningitis is associated with long-term neurophysiological impacts

A systematic literature review analyzing data from 21 African countries revealed that bacterial meningitis is associated with high case fatality and frequent neurophysiological sequelae. Pneumococcal and Hib meningitis contribute to one third of disease related mortality. They also cause clinically evident sequalae in 25% of survivors prior to hospital discharge. The three main causes of bacterial meningitis- Haemophilus influenzae type B; Streptococcus pneumoniae (pneumococcus) and Neisseria meningitidis (meningococcus) are vaccine preventable, routine use of conjugate vaccines have potential for significant health and economic benefits.

Neuropsychological sequelae includes hearing loss, vision loss, cognitive delay, speech/language disorder, behavioural problems, motor delays/impairment, and seizures.

Ramakrishnan, M., Ulland, A.J., Steinhardt, L.C., et al. 2009. Sequelae due to bacterial meningitis among African children: a systematic literature review. BMC Medicine. 7(47).