Field evaluation of validity and feasibility of Pan-Lassa rapid diagnostic test for Lassa fever in Abakaliki, Nigeria: a prospective diagnostic accuracy study.

BACKGROUND: Lassa fever is a viral haemorrhagic fever with few options for diagnosis and treatment; it is also under-researched with knowledge gaps on its epidemiology. A point-of-care bedside test diagnosing Lassa fever, adhering to REASSURED criteria, is not currently available but is urgently needed in west African regions with high Lassa fever burden. We aimed to assess the validity and feasibility of a rapid diagnostic test (RDT) to confirm Lassa fever in people in Nigeria. METHODS: We estimated the diagnostic performance of the ReLASV Pan-Lassa RDT (Zalgen Labs, Frederick, MD, USA) as a research-use-only test, compared to RT-PCR as a reference standard, in 217 participants at a federal tertiary hospital in Abakaliki, Nigeria. We recruited participants between Feb 17, 2022, and April 17, 2023. The RDT was performed using capillary blood at the patient bedside and using plasma at the laboratory. The performance of the test, based on REASSURED criteria, was assessed for user friendliness, rapidity and robustness, sensitivity, and specificity. FINDINGS: Participants were aged between 0 and 85 years, with a median age of 33·0 years (IQR 22·0-44·3), and 24 participants were younger than 18 years. 107 (50%) participants were women and 109 (50%) were men; one participant had missing sex data. Although the specificity of the Pan-Lassa RDT was high (>90%), sensitivity at bedside using capillary blood was estimated as 4% (95% CI 1-14) at 15 min and 10% (3-22) at 25 min, far below the target of 90%. The laboratory-based RDT using plasma showed better sensitivity (46% [32-61] at 15 min and 50% [36-64] at 25 min) but did not reach the target sensitivity. Among the 52 PCR-positive participants with Lassa fever, positive RDT results were associated with lower cycle threshold values (glycoprotein precursor [GPC] gene mean 30·3 [SD 4·3], Large [L] gene mean 32·3 [3·7] vs GPC gene mean 24·5 [3·9], L gene mean 28·0 [3·6]). Personnel conducting the bedside test procedure reported being hindered by the inconvenient use of full personal protective equipment and long waiting procedures before a result could be read. INTERPRETATION: The Pan-Lassa RDT is not currently recommended as a diagnostic or screening tool for suspected Lassa fever cases. Marked improvement in sensitivity and user friendliness is needed for the RDT to be adopted clinically. There remains an urgent need for better Lassa fever diagnostics to promote safety of in-hospital care and better disease outcomes in low-resource settings. FUNDING: Médecins Sans Frontières.

Promoting and supporting breastfeeding in a protracted emergency setting-Caregivers' and health workers' perceptions from North-East Nigeria.

Background: Breastfeeding (BF) should be protected, promoted, and supported for all infants in humanitarian settings. The re-establishment of exclusive BF is also a central part of the management of acutely malnourished infants under 6 months (<6 m). Médecins Sans Frontières (MSF) runs a nutrition project in Maiduguri, a protracted emergency setting in North-East Nigeria. This study aimed to explore caregivers' (CGs) and health workers' (HWs) perceptions of BF practice, promotion, and support among CGs with infants <6 m in this setting. Methods: We conducted a qualitative study using in-depth interviews and focus group discussions combined with non-participant observations. Participants included CGs of young infants enrolled in MSF nutritional programs or who attended health promotion activities in a displacement camp. MSF HWs were involved at different levels in BF promotion and support. Data were collected involving a local translator and analyzed using reflexive thematic analysis directly from audio recordings. Results: Participants described how feeding practices are shaped by family, community, and traditional beliefs. The perception of breastmilk insufficiency was common and led to early supplementary feeding with inexpensive but unsuitable products. Participants often linked insufficient breastmilk production with poor maternal nutrition and stress, in a context shaped by conflict and food insecurity. BF promotion was generally well received but could be improved if tailored to address specific barriers to exclusive BF. Interviewed CGs positively valued BF support received as part of the comprehensive treatment for infant malnutrition. One of the main challenges identified was the length of stay at the facility. Some participants perceived that improvements in BF were at risk of being lost after discharge if CGs lacked an enabling environment for BF. Conclusion: This study corroborates the strong influence of household and contextual factors on the practice, promotion, and support of BF. Despite identified challenges, the provision of BF support contributes to improvements in BF practice and was positively perceived by CGs in the studied setting. Greater attention should be directed toward providing support and follow-up for infants <6 m and their CGs in the community.