Ribavirin ampoule formulation remains a major challenge in managing Lassa fever disease. Lassa fever is an endemic viral hemorrhagic fever in the West Africa subregion, which has high-dose ribavirin as the standard of care. The high-dose therapy required makes the 200 mg/ml ampoule dosing of ribavirin a daunting task to administer, especially during disease outbreaks. This commentary highlights the challenges and makes a passionate call for vial dosage adjustment to fit the high-dose requirement of Lassa fever disease.

UNASSIGNED: Hand hygiene is recognized as the leading measure to prevent the cross-transmission of microorganisms and to reduce the incidence of healthcare-associated infections.
UNASSIGNED: To assess the knowledge and practice of hygiene among dental health workers even in the wake of Lassa fever.
UNASSIGNED: This questionnaire-based descriptive cross-sectional study was carried out in four public hospitals in Edo state. All data were collected using a self-administered structured questionnaire after obtaining ethical clearance.
UNASSIGNED: 108 of the 120 questionnaires distributed were filled and returned giving a response rate of 90.0%. Overall assessment of respondents\' knowledge of hand hygiene revealed that 41.7% of the respondents possessed a good knowledge of hand hygiene, 37.0% had excellent knowledge, 17.6% had moderate and 3.7% had a weak knowledge of hand hygiene. Overall assessment of the practice of hand hygiene showed that the hand hygiene practice of 58.3% of respondents was fair while 37.0% practiced hand hygiene poorly. Only a few (5.6%) respondents had good hand hygiene practices.
UNASSIGNED: The outbreak of Lassa fever does not seem to positively influence the practice of hand hygiene among the respondents. While knowledge of hand hygiene is satisfactory in this study, the practice still leaves much to be desired.

UNASSIGNED: Lassa fever is a viral hemorrhagic disease caused by the Lassa virus, a single stranded RNA virus of the Arenavirus family. It is a zoonotic illness spread by rats of the speciesMastomys natalensis . Between weeks 1 and 17, (2017), 242 suspected Lassa fever cases were reported in Nigeria, with 58 laboratory confirmed cases and 46 fatalities (CFR, 19.01%) from 50 Local Government Areas (LGAs) in 20 States.
UNASSIGNED: We conducted an outbreak investigation and gathered a thorough clinical history of the index case as well as contacts, who were then followed up using the standard viral hemorrhagic fever contact monitoring form. Following that, blood samples were collected from this patient. A total of 54 contacts were tracked for 21 days and their temperatures were recorded using a clinical thermometer. Furthermore, an environmental evaluation of the Zabarmari community and the Madinatu Internally-displaced persons\' (IDP) camp was carried out.
UNASSIGNED: The index case was a 32-year-old woman who was internallydisplaced in Zabarmari community. Her symptoms began with fever and vaginal bleeding and progressed to bleeding from the nose, mouth, and urethra. There was a history of rat exposure as well as inadequate environmental sanitation and hygiene. Real Time PCR detected Lassa fever in the blood sample. The Borno State Ministry of Environment, in partnership with the Ministry of Health, undertook public health education on Lassa fever prevention and implemented excellent sanitary measures.
UNASSIGNED: Increased awareness creation on good infection prevention and control practices is crucial among internally-displaced person and health care providers to prevent occurrence and spread of the disease.

Viral haemorrhagic fevers (VHF) pose a significant threat to human health. In recent years, VHF outbreaks caused by Ebola, Marburg and Lassa viruses have caused substantial morbidity and mortality in West and Central Africa. In 2022, an Ebola disease outbreak in Uganda caused by Sudan virus resulted in 164 cases with 55 deaths. In 2023, a Marburg disease outbreak was confirmed in Equatorial Guinea and Tanzania resulting in over 49 confirmed or suspected cases; 41 of which were fatal. There are no clearly defined correlates of protection against these VHF, impeding targeted vaccine development. Any vaccine developed should therefore induce strong and preferably long-lasting humoral and cellular immunity against these viruses. Ideally this immunity should also cross-protect against viral variants, which are known to circulate in animal reservoirs and cause human disease. We have utilized two viral vectored vaccine platforms, an adenovirus (ChAdOx1) and Modified Vaccinia Ankara (MVA), to develop a multi-pathogen vaccine regime against three filoviruses (Ebola virus, Sudan virus, Marburg virus) and an arenavirus (Lassa virus). These platform technologies have consistently demonstrated the capability to induce robust cellular and humoral antigen-specific immunity in humans, most recently in the rollout of the licensed ChAdOx1-nCoV19/AZD1222. Here, we show that our multi-pathogen vaccines elicit strong cellular and humoral immunity, induce a diverse range of chemokines and cytokines, and most importantly, confers protection after lethal Ebola virus, Sudan virus and Marburg virus challenges in a small animal model.

BACKGROUND: Lassa fever (LF) presents significant public health challenges in Sierra Leone, particularly in the Lower Bambara Chiefdom. This study aims to deeply understand how knowledge and attitudes towards LF correlate with community-driven prevention and control measures.
METHODS: A descriptive cross-sectional quantitative approach was used to conduct the research. Data from 2167 participants were collected using an Android-based survey from 1st February 2022 to 14th February 2022. Respondents\' knowledge of LF causes, risk factors, transmission modes, and preventive measures were evaluated through a multiple-choice questionnaire, and attitudes toward prevention and control were measured on a 5-point Likert scale. Quantitative data were analyzed using SPSS version 26.0 and frequencies were presented in count, percentage, and table. Chi-square statistics were used to test for associations.
RESULTS: Among the 2167 participants, over half were males (1184, 54.60%), farmers (1406, 64.90%), married (monogamous) (1428, 65.90%), and had never attended school (1336, 61.70%). Respondents demonstrated high knowledge levels of LF across socio-demographic groups (33% to 100%) and shared a positive attitude towards prevention and control (mean score of 26.77 on a 5-40 scale). Educational level, religious beliefs, and occupational status significantly influenced LF knowledge (p < 0.05). Specifically, illiterates had a high knowledge score of 48.24%, while those with tertiary education had the highest score at 83.33%. Additionally, a Pearson correlation analysis revealed a positive linear relationship between the degree of knowledge and positive attitude towards LF infection and mortality risk factors (r = 0.090, p = 0.02).
CONCLUSIONS: High LF knowledge in Lower Bambara Chiefdom positively influences prevention attitudes. Education, religion, and occupation are key factors. Tailored interventions enhance public health efforts.

Lassa fever (LF), caused by Lassa virus (LASV), is one of the most dangerous diseases to public health. Homologous recombination (HR) is a basic genetic power driving biological evolution. However, as a negative-stranded RNA virus, it is unknown whether HR occurs between LASVs and its influence on the outbreak of LF. In this study, after analyzing 575 S and 433 L segments of LASV collected in Africa, we found that LASV can achieve HR in both of its segments. Interestingly, although the length of S segment is less than half of the L segment, the proportion of LASVs with S recombinants is significantly higher than that with L recombinants. These results suggest that HR may be a feature of LASV, which can be set by natural selection to produce beneficial or eliminate harmful mutations for the virus, so it plays a role in LASV evolution during the outbreak of LF.

The mammarenavirus Lassa virus (LASV) causes the life-threatening hemorrhagic fever disease, Lassa fever. The lack of licensed medical countermeasures against LASV underscores the urgent need for the development of novel LASV vaccines, which has been hampered by the requirement for a biosafety level 4 facility to handle live LASV. Here, we investigated the efficacy of mRNA-lipid nanoparticle (mRNA-LNP)-based vaccines expressing the LASV glycoprotein precursor (LASgpc) or nucleoprotein (LCMnp) of the prototypic mammarenavirus, lymphocytic choriomeningitis virus (LCMV), in mice. Two doses of LASgpc- or LCMnp-mRNA-LNP administered intravenously (i.v.) protected C57BL/6 mice from a lethal challenge with a recombinant (r) LCMV expressing a modified LASgpc (rLCMV/LASgpc2m) inoculated intracranially. Intramuscular (i.m.) immunization with two doses of LASgpc- or LCMnp-mRNA-LNP significantly reduced the viral load in C57BL/6 mice inoculated i.v. with rLCMV/LASgpc2m. High levels of viremia and lethality were observed in CBA mice inoculated i.v. with rLCMV/LASgpc2m, which were abrogated by i.m. immunization with two doses of LASgpc-mRNA-LNP. The protective efficacy of two i.m. doses of LCMnp-mRNA-LNP was confirmed in a lethal hemorrhagic disease model of FVB mice i.v. inoculated with wild-type rLCMV. In all conditions tested, negligible and high levels of LASgpc- and LCMnp-specific antibodies were detected in mRNA-LNP-immunized mice, respectively, but robust LASgpc- and LCMnp-specific CD8+ T cell responses were induced. Accordingly, plasma from LASgpc-mRNA-LNP-immunized mice did not exhibit neutralizing activity. Our findings and surrogate mouse models of LASV infection, which can be studied at a reduced biocontainment level, provide a critical foundation for the rapid development of mRNA-LNP-based LASV vaccines.IMPORTANCELassa virus (LASV) is a highly pathogenic mammarenavirus responsible for several hundred thousand infections annually in West African countries, causing a high number of lethal Lassa fever (LF) cases. Despite its significant impact on human health, clinically approved, safe, and effective medical countermeasures against LF are not available. The requirement of a biosafety level 4 facility to handle live LASV has been one of the main obstacles to the research and development of LASV countermeasures. Here, we report that two doses of mRNA-lipid nanoparticle-based vaccines expressing the LASV glycoprotein precursor (LASgpc) or nucleoprotein (LCMnp) of lymphocytic choriomeningitis virus (LCMV), a mammarenavirus genetically closely related to LASV, conferred protection to recombinant LCMV-based surrogate mouse models of lethal LASV infection. Notably, robust LASgpc- and LCMnp-specific CD8+ T cell responses were detected in mRNA-LNP-immunized mice, whereas no virus-neutralizing activity was observed.

Lassa virus (LASV), a risk-group 4 pathogen, must be handled in biosafety level-4 (BSL-4) conditions, thereby limiting its research and antiviral development. Here, we developed a novel LASV reverse genetics system which, to our knowledge, is the first to study the complete LASV life cycle under BSL-2 conditions. Viral particles can be produced efficiently when LASV minigenomic RNA harbouring minimal viral cis-elements and reporter genes is transfected into a helper cell line stably expressing viral NP, GP, Z and L proteins. The resulting defective virions, named LASVmg, can propagate only in the helper cell line, providing a BSL-2 model to study the complete LASV life cycle. Using this model, we found that a previously reported cellular receptor α-dystroglycan is dispensable for LASVmg infection. Furthermore, we showed that ribavirin can inhibit LASVmg infection by inducing viral mutations. This new BSL-2 system should facilitate studying the LASV life cycle and screening antivirals.

UNASSIGNED: Lassa fever is a critical public health issue in Sierra Leone that demands appropriate health system responses and interventions to mitigate infections and reduce mortality.
UNASSIGNED: A qualitative study was conducted to delve into healthcare workers\' experiences with Lassa fever management and interventions across diverse healthcare settings in Sierra Leone, including the Eastern Province and Freetown\'s Directorate of Health Security and Emergency (DHSE). Engaging ten key informants through purposive sampling, the study employed NVivo version 10 for a detailed thematic analysis using Query and Coding to systematically identify, classify, and organize key themes regarding knowledge, diagnostics, management roles, and community impact.
UNASSIGNED: The findings indicate a well-informed healthcare workforce but highlight gaps in early detection, diagnostic accuracy, and procedural standardization. Concerns were raised about the potential overestimation of disease incidence due to improved diagnostics, suggesting a historical under-detection of Lassa fever. The analysis underscores the need for a multifaceted management approach, emphasizing international collaboration and culturally sensitive community engagement to effectively tackle the disease. A significant concern identified is the high mortality rate resulting from delayed referrals and communication challenges within the health system, leading to actionable recommendations for enhancing Lassa fever response strategies. The study\'s thematic analysis provides a nuanced understanding of the challenges and areas for improvement, emphasizing the critical role of healthcare professionals in combating Lassa fever.
UNASSIGNED: Combating Lassa fever in Sierra Leone demands an integrative strategy that extends beyond medical interventions to encompass educational and infrastructural enhancements. This research pays homage to the commitment of healthcare professionals, underscoring the importance of sustained support and recognition of their essential contributions to advancing Lassa fever management and interventions.

UNASSIGNED: We investigated an outbreak of Lassa fever that occurred in Ebonyi state, Southeast Nigeria from January to March 2018.
UNASSIGNED: The Emergency operational centre (EOC) model was used for the outbreak coordination. Cases and deaths were identified through the routine surveillance system. Blood specimens collected from suspected cases were sent for confirmation at the Virology Centre, Alex Ekwueme Federal University Teaching Hospital, Abakaliki (AEFUTHA). Active case search was instituted, and identified contacts of confirmed cases were followed up for the maximum incubation period of the disease. Other public health responses included infection prevention and control, communication and advocacy as well as case management. Data collected were analysed using the Epi info statistical software package.
UNASSIGNED: We identified 89 suspected Lassa Fever (LF) cases out of which 61 were confirmed. The mean age was 35±16.2 and the age group mostly affected was 30-39 years. More than half (59.7%) of the confirmed cases were females. The Case Fatality Rate (CFR) was 26.2% among the laboratory confirmed cases. Five of the deaths occurred among health care workers. Out of 325 contacts of the confirmed cases, 304(99.7%) completed the follow-up and only 1(0.3%) of them developed symptoms consistent with LF and was confirmed by the laboratory.
UNASSIGNED: The high CFR in those presenting late to the hospital underscores the need for intensive public enlightenment that encourages early presentation to hospital. Majority of the confirmed cases were primary cases, hence efforts should be intensified in breaking the chain of transmission in the animal-man interphase. Death of healthcare workers involved in management of Lassa fever raises the importance of providing life insurance for concerned healthcare workers.