A systemic review of literatures on human Salmonella enterica serovars in Nigeria (1999-2018)

Abstract

Introduction: Salmonella infections are endemic in Nigeria. There is lack of reliable data on culture-positive Salmonella with national coverage. This systemic review of literatures was undertaken to aggregate data on culture proven cases of human Salmonellae and to determine the prevailing serotypes for disease burden estimations.
 Methodology: This involved comprehensive search engines of Pubmed, Google Scholar, Google and Embase for the literatures on culture positive human Salmonellae from 1999-2018. This review documented the prevalence, common Salmonella serotypes. antibiotic resistance and risk factors associated with human Salmonella infections.
 Results: This study revealed that 21out of 36 States in Nigeria reported Salmonella-associated diseases, spanning the six geopolitical zones. Our study revealed prevalence of 1.9% (2,732/143,756) Salmonella-bacteraemia and 16.3% (1,967/12,081) Salmonella-associated gastroenteritis. Fifty-three 53 Salmonella serotypes were identified. 39 serotypes were associated with Salmonella-bacteraemia and 31 serotypes with Salmonella-gastroenteritis. Salmonella typhi remains the commonest serotype accounting for 85.2% for Salmonella-bacteraemia and 73.1% Salmonella-gastroenteritis. S. typhimurium (3.8%) was mostly implicated invasive non-typhoidal serotype followed S. enteritidis (2.8%) among others. Human Immunodeficiency Virus-infected individuals, malnutrition was among factors predisposing Salmonella infections. Over 60% of the reported Salmonella isolates developed resistance to two or more of 23 antibiotics recorded, mostly ampicillin, cotrimoxazole, tetracycline and amoxicillin.
 Conclusions: This study revealed 39 Invasive and 31 non-invasive Salmonella serotypes. Ampicillin, cotrimoxazole, amoxicillin-clavulanate and tetracycline are the most frequently reported antibiotics resisted by Salmonella isolates. This antimicrobial resistance exhibited poses a threat to public health. Data generated from this review would serve as a baseline information for future surveillance studies.

Genomic characterization of invasive typhoidal and non-typhoidal Salmonella in southwestern Nigeria

“…Using high-throughput WGS and bioinformatic analytics, we were able to determine prevalent serotypes and dominant genotypes of invasive Salmonella infections. Most of the Salmonella isolates cultured from blood were S. Typhi, as has been previously reported from different parts of Nigeria, including Ibadan [28][29][30], even though iNTS may predominate in some other African settings [3,31]. While our data are few, the predominance of Typhi at all sites points to a significant burden of severe disease that could be averted if Typhoid Conjugate Vaccines were deployed in Nigeria.…”

Review of Salmonella Characteristics, History, Taxonomy, Nomenclature, Non Typhoidal Salmonellosis (NTS) and Typhoidal Salmonellosis (TS)

“…Worldwide, foodborne diseases caused by Salmonella have been of public health concern for over a century [12]. Salmonella diseases are grouped into typhoidal salmonellosis (TS, enteric fever) and non-typhoidal Salmonella (NTS) associated infections [13,14]. Salmonella enterica serovar Typhi causes typhoid fever and S. Paratyphi A, B and C cause human host restricted paratyphoid fever [13].…”

“…Salmonella diseases are grouped into typhoidal salmonellosis (TS, enteric fever) and non-typhoidal Salmonella (NTS) associated infections [13,14]. Salmonella enterica serovar Typhi causes typhoid fever and S. Paratyphi A, B and C cause human host restricted paratyphoid fever [13]. The cause of NTS infections is a group of S. enterica serovars [14].…”

Persistence of anti-Salmonella O9 IgM as measured by Tubex® TF may contribute to the over-diagnosis of typhoid fever in endemic areas

“…[1][2][3] The infection can manifest as a mild to severe illness depending on various factors, such as age, bacterial strain, current intake of H 2 blockers, and co-infection with HIV or Helicobacter pylori. [4][5][6] In a mild or acute non-complicated case, the disease is characterized by fever, malaise, constipation (adult) or diarrhea (children), frontal headache, nausea, and anorexia with slight dry cough. 2, 6 In approximately 5-30% of patients, rose-colored spots appear on the chest and abdomen and sometimes on the back and limbs.…”