A retrospective study revealing complex viral diversity and a substantial burden of HPV infection in SARS-CoV-2 positive individuals, Sierra Leone.

Background: The COVID-19 pandemic has underscored the critical role of sequencing technology in disease control and outbreak response. However, resource limitations and challenging environments often impede such efforts in low and middle-income countries. This study aimed to investigate the spectrum of viral co-infections, particularly with human viral pathogens, in SARS-CoV-2 positive individuals in Sierra Leone using metagenomic sequencing, evaluating the feasibility of utilizing this technology for epidemiological and evolutionary surveillance of pathogens related to public health in low-income environments.

Post-Omicron SARS-CoV-2 serostatus in Sierra Leone: A cross-sectional study in a maternity hospital setting in Freetown, November/December 2022.

Background: Spread of SARS-CoV-2 in Sub-Saharan African countries has been poorly investigated, especially in the later pandemic stages. We aimed to assess the post-Omicron situation in Sierra Leone in November/December 2022 considering SARS-CoV-2 serostatus, vaccinations, and behavioral factors.

Methods: In a cross-sectional study conducted in a maternity hospital in Freetown, Sierra Leone, both patients and staff provided dried blood spot samples for analysis of anti-S and anti-N IgG prevalence using Anti-SARS-CoV-2-ELISA.

Molecular characterization of an outbreak-involved Bacillus anthracis strain confirms the spillover of anthrax from West Africa.

Background: Anthrax, a zoonotic disease caused by the spore-forming bacterium Bacillus anthracis, remains a major global public health concern, especially in countries with limited resources. Sierra Leone, a West African country historically plagued by anthrax, has almost been out of report on this disease in recent decades. In this study, we described a large-scale anthrax outbreak affecting both animals and humans and attempted to characterize the pathogen using molecular techniques.

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.

Epidemiological Trends of Coronavirus Disease 2019 in Sierra Leone From March 2020 to October 2021.

Coronavirus disease 2019 (COVID-19), a serious public health challenge the world over, has led to significant health concerns in Sierra Leone. In the present study, epidemic indices, such as the number of cases, positivity rate, reproduction rate (R0), case fatality rate (CFR), age, and sex, were used to characterize the epidemiological trends of COVID-19. As of October 31, 2021, a total of 6,398 cases and 121 related deaths had been confirmed.

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

Invasive 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 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 infection among fever patients.

The dynamic change of SARS-CoV-2 variants in Sierra Leone.

Since the beginning of the SARS-CoV-2 pandemic, the emergence of multiple new variants posed an increased risk to global public health. The aim of this study is to investigate SARS-CoV-2 variants and possible transmission of variants of concern (VOCs) in Sierra Leone. A total of 65 nasal swab samples were collected from COVID-19 cases in Sierra Leone, among which 24 samples were collected during the second wave and 41 samples were collected during the third wave.

The deployment of mobile diagnostic laboratories for Ebola virus disease diagnostics in Sierra Leone and Guinea.

Background: Ebola virus emerged in West Africa in December 2013. The ease of mobility, porous borders, and lack of public health infrastructure led to the largest Ebola virus disease (EVD) outbreak to date.

Intervention: The 2013 EVD outbreak signalled the need for laboratory diagnostic capabilities in areas without strong public health systems.

High Levels of Antibiotic Resistance Patterns in Two Referral Hospitals during the Post-Ebola Era in Free-Town, Sierra Leone: 2017-2019.

The Post-Ebola era (2017-2019) presented an opportunity for laboratory investments in Sierra Leone. US CDC supported the Ministry of Health and Sanitation to establish a microbiological unit for routine antimicrobial sensitivity testing in two referral (pediatric and maternity) hospitals in Freetown. This study describes resistance patterns among patients' laboratory samples from 2017 to 2019 using routine data.

Establishing an enteric bacteria reference laboratory in Sierra Leone.

In 2012, Sierra Leone experienced its worst cholera outbreak in over 15 years affecting 12 of the country's 13 districts. With limited diagnostic capability, particularly in bacterial culture, the cholera outbreak was initially confirmed by microbiological testing of clinical specimens outside of Sierra Leone. During 2012 - 2013, in direct response to the lack of diagnostic microbiology facilities, and to assist in investigating and monitoring the cholera outbreak, diagnostic and reference services were established in Sierra Leone at the Central Public Health Reference Laboratory focusing specifically on isolating and identifying Vibrio cholerae and other enteric bacterial pathogens.