Molecular diagnostics and next-generation sequencing reveal real etiological characteristics of invasive Salmonella infection in febrile illness in Freetown, Sierra Leone.

Invasive Salmonella infection, which can cause typhoid/paratyphoid fever and invasive non-typhoidal salmonellosis, is a public health burden in Africa. Accurate diagnosis and etiological characterization are required to conduct prevalence and risk estimations for Salmonella infection; however, the utilization of optimal techniques and surveillance data are still insufficient. In this study, we performed a laboratory-based survey in Freetown, which is the biggest city in Sierra Leone with a high burden of typhoid fever, by using blood culture and molecular methods but not the Widal test, to estimate the prevalence and aetiology of invasive Salmonella infection among fever patients. We found a very low prevalence of typhoid fever in patients with fever during the investigation period, and this prevalence was clearly overestimated by the Widal test. Genome sequencing of the S. Typhi isolate from this work revealed that the strain carried multiple antibiotic resistance genes, and an epidemic clone that has existed in West Africa for years was also detected in Sierra Leone. By using metagenomic sequencing, one patient with invasive non-typhoidal salmonellosis was identified as having bacterial co-infections. Our data highlight that Salmonella surveillance based on accurate laboratory diagnosis and genome sequencing needs to be strengthened to provide a better estimation of the real epidemics and enable potential risk assessment by etiological analysis in Africa. Even in a laboratory with only basic equipment, it is possible to conduct next-generation sequencing for pathogen discovery in bloodstream infections and to determine the etiological characteristics of pathogene without complex combinations of laboratory methods.

Dissemination of Antibiotic Resistance Genes Among Patients with Diarrhea - Freetown, Sierra Leone, 2018.

What is already known about this topic?: Antibiotic resistance (AR) is a serious public health threat worldwide. However, the AR and antibiotic resistance genes (ARGs) data from West Africa, especially from Sierra Leone, are limited. What is added by this report?: The study revealed ARGs' common dissemination, and multiplex antibiotic resistance genes in one sample. Genes bla NDM and bla OXA -48-like were first discovered in Sierra Leone. What are the implications for public health practice?: Basic information is provided for AR research and surveillance and highlights that effective AR surveillance among diarrhea patients is necessary for Sierra Leone and West Africa.

A Household-Based Cross-Sectional Survey of Knowledge, Awareness and Practice Regarding Malaria in Western Area Rural District, Sierra Leone.

Sierra Leone is a highly endemic area for malaria, and the implementation of the National Malaria Strategic Plan (2016-2020) has reached its midpoint in 2018. To provide more specific guidance for interventions in the future, a household-based cross-sectional survey was conducted to elucidate the knowledge, awareness and practices regarding malaria and malarial control measures among the general public. Three communities (Grafton, Jui, and Kossoh) in the Western Area Rural District that were in close proximity to Sierra Leone's capital city of Freetown were included. Households were randomly selected and interviewed with a structured questionnaire covering malaria infection, diagnosis, treatment and prevention, as well as knowledge of malaria prevention. As a result, a total of 262 qualified questionnaires were included. The average cost for meals per day is ~30,000 Leones in each household. The rate of awareness, indicated by reporting having heard of malaria, was 98.1% (257/262), and 86.6% (227/262) of the respondents knew that mosquito bites are the main route of transmission. In addition, 80.9% (212/262) of the respondents sought health advice or treatment for the illness, and a similar percentage of respondents had been tested for malaria, mostly with rapid diagnostic tests (RDTs). A high demand for long-lasting insecticidal nets (72.1%) matched the serious shortage (61.8%, 162/262), and of the households that reported a lack of nets, 66 had children younger than 5 years old. In conclusion, public awareness of malaria prevention is high, based on this survey, although there was a limited use of preventive measures in these three communities and the malaria burden was still high. Therefore, the public's knowledge of malaria should be sustained and reinforced, and the distribution and use of malaria prevention measures should be promoted to supprt the achievement of the planned objectives.