ABSTRACT
The 2018 Nigerian Lassa fever season saw the largest ever recorded upsurge of cases, raising concerns over the emergence of a strain with increased transmission rate. To understand the molecular epidemiology of this upsurge, we performed, for the first time at the epicenter of an unfolding outbreak, metagenomic nanopore sequencing directly from patient samples, an approach dictated by the highly variable genome of the target pathogen. Genomic data and phylogenetic reconstructions were communicated immediately to Nigerian authorities and the World Health Organization to inform the public health response. Real-time analysis of 36 genomes and subsequent confirmation using all 120 samples sequenced in the country of origin revealed extensive diversity and phylogenetic intermingling with strains from previous years, suggesting independent zoonotic transmission events and thus allaying concerns of an emergent strain or extensive human-to-human transmission.
Subject(s)
Disease Outbreaks , Lassa Fever/virology , Lassa virus/genetics , Metagenomics/methods , Molecular Epidemiology , Animals , Genome, Viral , Humans , Lassa Fever/transmission , Nigeria/epidemiology , Phylogeny , Zoonoses/transmission , Zoonoses/virologyABSTRACT
BACKGROUND: Markets provide a forum for reaching a large adult population with information on Lassa fever, and therefore understanding the food handling practices of traders may provide the foundation for an effective campaign against Lassa fever. This study was undertaken to provide baseline information on knowledge and food handling practices of traders in local markets in a Lassa fever endemic state of Nigeria. STUDY DESIGN: A structured questionnaire was used to obtain food handling habits that facilitate the transmission of Lassa virus from a cross sectional study involving 385 traders in three major markets in Edo state and data analyzed using SPSS version 15. RESULTS: Two hundred and ninety three (76.1%) had ever heard of Lassa fever, 27 (9.2%) had good knowledge. Good knowledge was significantly associated with higher educational status (p < 0.00) and male gender (p=0.03). Thirty seven (12.6%) respondents sun-dried their food frequently, 105 (35.8%) stored utensils in rodent proof containers, and 136 (46.4%) had the habit of eating garri soaked in water. One hundred and ninety (49.4%) respondents had food hygiene practices that were favorable for spread of Lassa fever. CONCLUSION: The observed gaps in knowledge of Lassa fever and food hygiene may be addressed through tailored health messages. In this way, market campaigns will be effective in increasing knowledge of Lassa fever, and traders can themselves become peer educators.
