A Systematic Review of Typhoid Fever Occurrence in Africa

Abstract

BackgroundOur current understanding of the burden and distribution of typhoid fever in Africa relies on extrapolation of data from a small number of population-based incidence rate estimates. However, many other records on the occurrence of typhoid fever are available, and those records contain information that may enrich our understanding of the epidemiology of the disease as well as secular trends in reporting by country and over time.MethodsWe conducted a systematic review of typhoid fever occurrence in Africa, published in PubMed, Embase, and ProMED (Program for Monitoring Emerging Diseases).ResultsAt least one episode of culture-confirmed typhoid fever was reported in 42 of 57 African countries during 1900–2018. The number of reports on typhoid fever has increased over time in Africa and was highly heterogeneous between countries and over time. Outbreaks of typhoid fever were reported in 15 countries, with their frequency and size increasing over time.ConclusionsEfforts should be made to leverage existing typhoid data, for example, by incorporating them into models for estimating the burden and distribution of typhoid fever.

Classification of Salmonella enterica of the (Para-)Typhoid Fever Group by Fourier-Transform Infrared (FTIR) Spectroscopy

“…Compared to expensive and laborious approaches like next-generation sequencing-based typing, the IR biotyping approach allows typing within few minutes at reagents costs of few cents as far as a biotyping device is available. However, as (para-)typhoid fever is predominantly prevalent in resource-limited settings [ 9 , 12 , 13 , 14 , 15 , 16 ] where biotyping devices are so far not readily available, the broader application of the introduced approach needs to be awaited.…”

“…While severe invasive disease due to enteric Salmonella has frequently been associated with young age and immunocompromised states [ 4 , 6 ], typhoid fever-associated Salmonella are also affecting immunocompetent individuals [ 7 , 8 ] and seem to be more prevalent in adult patients [ 7 , 8 ]. In febrile patients in tropical endemicity settings, typhoid fever is an important differential diagnosis to malaria [ 9 ], although co-infections are predominantly observed for non-typhoidal Salmonella [ 10 ].…”

“…The Paratyphi A-C serovars are typically associated with clinically less severe disease as opposed to infections caused by the serovar Typhi [ 11 ]. While Salmonella Typhi ( S. Typhi) has a worldwide distribution in tropical areas and is associated with poor hygiene conditions [ 9 ], areas of endemicity for paratyphoid fever are mainly Asia and Africa, with a particularly high incidence of 150 cases/100,000 persons years in China [ 12 , 13 , 14 , 15 , 16 ]. Until now, global screening and surveillance efforts still leave room for improvement [ 17 ].…”

Enteric fever

“…Poor access to clean drinking water and inadequate sanitation and hygiene increase the risk of transmission 56. Enteric fever is most common in South Asia (incidence >500 per 100 000 population); South-East Asia, sub-Saharan Africa, and Oceania (>100 per 100 000 population); and Latin America and Caribbean (1-10 per 100 000 population) 17. Children and young adults are more commonly affected 8910.…”

The Severe Typhoid Fever in Africa Program Highlights the Need for Broad Deployment of Typhoid Conjugate Vaccines

“…The authors summarize key published data through three systematic reviews—one on published typhoid fever data from Africa since 1950, one on spatial and temporal patterns of typhoid and paratyphoid fever outbreaks globally between 1990 and 2016, and one on frequency of complications associated with severe disease. The first reports that 42 of 57 African countries have reported at least 1 typhoid fever case during this time period, with the total number of reports increasing over time [21]. The second unsurprisingly describes the high proportion (66%) of outbreaks that are causally linked to contaminated water [22].…”