A Systematic Review of the Incidence, Risk Factors and Case Fatality Rates of Invasive Nontyphoidal <i>Salmonella</i> (iNTS) Disease in Africa (1966 to 2014)

<div><p>This study systematically reviews the literature on the occurrence, incidence and case fatality rate (CFR) of invasive nontyphoidal <i>Salmonella</i> (iNTS) disease in Africa from 1966 to 2014. Data on the burden of iNT<i>S</i> disease in Africa are sparse and generally have not been aggregated, making it difficult to describe the epidemiology that is needed to inform the development and implementation of effective prevention and control policies. This study involved a comprehensive search of PubMed and Embase databases. It documents the geographical spread of iNTS disease over time in Africa, and describes its reported incidence, risk factors and CFR. We found that Nontyphoidal <i>Salmonella</i> (NTS) have been reported as a cause of bacteraemia in 33 out of 54 African countries, spanning the five geographical regions of Africa, and especially in sub-Saharan Africa since 1966. Our review indicates that NTS have been responsible for up to 39% of community acquired blood stream infections in sub-Saharan Africa with an average CFR of 19%. <i>Salmonella</i> Typhimurium and Enteritidis are the major serovars implicated and together have been responsible for 91%% of the cases of iNTS disease, (where serotype was determined), reported in Africa. The study confirms that iNTS disease is more prevalent amongst Human Immunodeficiency Virus (HIV)-infected individuals, infants, and young children with malaria, anaemia and malnutrition. In conclusion, iNTS disease is a substantial cause of community-acquired bacteraemia in Africa. Given the high morbidity and mortality of iNTS disease in Africa, it is important to develop effective prevention and control strategies including vaccination.</p></div

Map of Africa showing number of publications from countries reporting NTS blood culture isolates.

<p>Regions are indicated using coloured boundaries based on United Nations classification</p

Risk factors associated with iNTS disease in Africa (1966 to 2014)

<p>Risk factors associated with iNTS disease in Africa (1966 to 2014)</p

Published reports of incidence of iNTS disease in Africa (1966 to 2014)

<p>Published reports of incidence of iNTS disease in Africa (1966 to 2014)</p

Proportion of Community acquired blood stream infections caused by NTS in African countries (1966 to 2014)

<p>Proportion of Community acquired blood stream infections caused by NTS in African countries (1966 to 2014)</p

Published reports of iNTS disease in Africa by year of publication

<p>Published reports of iNTS disease in Africa by year of publication</p

Strategy for selection of eligible articles.

<p>Adapted from the PRISMA group 2009 flow diagram [<a href="http://www.plosntds.org/article/info:doi/10.1371/journal.pntd.0005118#pntd.0005118.ref203" target="_blank">203</a>].</p

CFR of iNTS disease from studies in Africa (1966 to 2014)

<p>CFR of iNTS disease from studies in Africa (1966 to 2014)</p

Pathogens reported from community acquired bacteraemia cases in Africa (1966 to 2014)

<p>Pathogens reported from community acquired bacteraemia cases in Africa (1966 to 2014)</p

Polio in Nigeria: A review of the situation and problems hindering its elimination

Nigeria is important to the polio eradication for the fact that a large proportion of importation into polio-free countries following elimination have been from Nigeria. It is the only country endemic for both Wild Polio Virus 1 and 3 as well as circulating Vaccine Derived Polio Virus type 2. We reviewed the pertinent literature including published and unpublished, official reports and working documents of the Global Polio Eradication Initiative (GPEI) partners as well as other concerned organizations. The literature were selected based on the following criteria: published in English Language, published after year 2000, relevant content and conformance to the theme of the review and these were sorted accordingly. The challenges facing the Polio Eradication Initiative (PEI) in Nigeria were found to fall into three categories viz failure to vaccinate, failure of the Oral Polio Vaccine (OPV) and epidemiology of the virus. Failure to vaccinate resulted from insecurity, heterogeneous political support, programmatic limitation in implementation of vaccination campaigns, poor performance of vaccination teams in persistently poor performing Local Government areas and vaccine refusals in Northern Nigeria. Sub optimal effectiveness of OPV in some settings as well as the problems of VDPVs associated with OPV type 2 were also indicted. Some of the innovations meant to manage the threats to the PEI include a strong government accountability frame work, change from type 2 containing OPV to monovalent and bi valent OPVs for supplementary immunization activities, sustaining environmental surveillance in key states (Sokoto, Kano and Borno) with an overall improvement in SIA quality. There has been an improvement in coverage of routine immunization and vaccination campaigns, which has been reflected in reduction in the number of new cases; 6 in total for 2014. However, the last mile remains and there is need to further improve and complete the journey towards polio elimination