This is the first report on the molecular identification and phylogeny of the Rousettus leschenaultii Desmarest, 1810, Rhinolophus rouxii Temminck, 1835, Hipposideros speoris Schneider, 1800, Hipposideros lankadiva Kelaart, 1850, and Miniopterus fuliginosus Kuhl, 1817, bat species in Sri Lanka, inferred from analyses by mitochondrially encoded cytochrome b gene sequences. Recent research has indicated that bats show enormous cryptic genetic diversity. Moreover, even within the same species, the acoustic properties of echolocation calls and morphological features such as fur color could vary in different populations. Therefore, we have used molecular taxonomy for the accurate identification of five bat species recorded in one of the largest cave populations in Sri Lanka. The bats were caught using a hand net, and saliva samples were collected non-invasively from each bat by using a sterile oral swab. Nucleic acids were extracted from the oral swab samples, and mitochondrial DNA was amplified by using primers targeting the mitochondrially encoded cytochrome b gene. This study reports the first molecular evidence for the identification of five bat species in Sri Lanka. Our findings will contribute to future conservation and systematic studies of bats in Sri Lanka. This study will also provide the basis for a genetic database of Sri Lankan bats which will contribute significantly to the investigation of potentially zoonotic bat viruses.

Highly pathogenic Arenaviruses, like the Lassa Virus (LASV), pose a serious public health threat in affected countries. Research and development of vaccines and therapeutics are urgently needed but hampered by the necessity to handle these pathogens under biosafety level 4 conditions. These containment restrictions make large-scale screens of antiviral compounds difficult. Therefore, the Mopeia virus (MOPV), closely related to LASV, is often used as an apathogenic surrogate virus. We established for the first time trisegmented MOPVs (r3MOPV) with duplicated S segments, in which one of the viral genes was replaced by the reporter genes ZsGreen (ZsG) or Renilla Luciferase (Rluc), respectively. In vitro characterization of the two trisegmented viruses (r3MOPV ZsG/Rluc and r3MOPV Rluc/ZsG), showed comparable growth behavior to the wild type virus and the expression of the reporter genes correlated well with viral titer. We used the reporter viruses in a proof-of-principle in vitro study to evaluate the antiviral activity of two well characterized drugs. IC₅₀ values obtained by Rluc measurement were similar to those obtained by virus titers. ZsG expression was also suitable to evaluate antiviral effects. The trisegmented MOPVs described here provide a versatile and valuable basis for rapid high throughput screening of broadly reactive antiviral compounds against arenaviruses under BSL-2 conditions.

Bats are known as typical reservoirs for a number of viruses, including viruses of the family Paramyxoviridae. Representatives of the subfamily Orthoparamyxovirinae are distributed worldwide and can cause mild to fatal diseases when infecting humans. The research on Paramyxoviruses (PMVs) from different bat hosts all over the world aims to understand the diversity, evolution and distribution of these viruses and to assess their zoonotic potential. A high number of yet unclassified PMVs from bats are recorded. In our study, we investigated bat species from the families Rhinolophidae, Hipposiderae, Pteropodidae and Miniopteridae that are roosting sympatrically in the Wavul Galge cave (Koslanda, Sri Lanka). The sampling at three time points (March and July 2018; January 2019) and screening for PMVs with a generic PCR show the presence of different novel PMVs in 10 urine samples collected from Miniopterus fuliginosus. Sequence analysis revealed a high similarity of the novel strains among each other and to other unclassified PMVs collected from Miniopterus bats. In this study, we present the first detection of PMVs in Sri Lanka and the presence of PMVs in the bat species M. fuliginosus for the first time.

Viral hemorrhagic fevers (VHFs), including filoviruses, Lassa virus, yellow fever virus and dengue virus, remain a major public health threat in resource-limited settings. The 2014–2016 Ebola epidemic exposed critical gaps in laboratory preparedness and diagnostic capacity in most-at-risk countries, including Guinea. In order to implement sustainable in-country laboratory capacity for early detection and rapid response to VHF outbreaks, a decentralized diagnostics laboratory strengthening program started in the forested region of Guinea in Guéckédou (2017) and N’Zérékoré (2021). Between 2017 and 2024, a total of 4683 samples from suspected VHF cases were tested across the two laboratories. Of those, 47 (1%) were identified as positive for VHFs by molecular testing, including the 2021 Ebola virus disease resurgence and Marburg virus disease emergence samples, for which the laboratories supported rapid outbreak detection and case management. Notably, between 2020 and 2024, 30 Lassa fever cases were laboratory-confirmed with a case fatality rate of 67.9%. Of those, 66.7% were men, with 50.0% and 27.6% of the cases originating from the Guéckédou and N’Zérékoré prefecture, respectively. Prior to this program, Lassa fever detection in Guinea remained anecdotic. One case of yellow fever and one of dengue were also identified by molecular assays. The establishment of locally embedded laboratory infrastructure enhanced VHFs preparedness, surveillance, and response in Guinea. Beyond improving understanding of Lassa fever epidemiology, this program highlights the value of sustained laboratory capacity for early detection and health system resilience in VHF-endemic settings.

Background: Herpesviruses are highly diverse and widely distributed pathogens infecting a broad range of animal hosts, including bats. Despite this wide distribution, they are typically extremely species-specific in their host associations. To better understand herpesvirus diversity in Sri Lankan bats, we screened 391 oral swab samples collected from five different bat species inhabiting Wavulgalge cave, Wellawaya (Uva Province, Sri Lanka) during three sampling periods (March 2018, July 2018, and January 2019) for herpesvirus DNA. A nested PCR assay was used, targeting the DNA polymerase gene of Herpesviruses. Results: In total, 152 samples (38.87%) were tested positive, within five bat species ( Hipposideros speoris (9/22), Hipposideros lankadiva (2/4), Miniopterus phillipsi (61/224), Rousettus leschenaultii (18/46), and Rhinolophus rouxii (62/95). Statistical analysis indicated no significant difference in overall detection rates among species ( p > 0.05), whereas prevalence varied significantly across sampling periods ( p < 0.05), suggesting temporal factors such as breeding cycles or roosting behavior may influence virus transmission. Phylogenetic analysis showed that all sequences formed a distinct Sri Lankan clade, separate from global bat herpesviruses, and were distributed into two groups corresponding to betaherpesviruses and gammaherpesviruses. Alphaherpesviruses were not detected. Conclusions: Notably, sequences did not cluster by host bat species, suggesting limited host specificity among the Sri Lankan bat species examined. The high prevalence across multiple species highlights the complex host–virus dynamics. Overall, this study provides the first characterization of herpesviruses in Sri Lankan bats, contributing to global knowledge of bat virology.

Between 2017 and 2024, routine diagnostics surveillance in Guinea detected several confirmed viral hemorrhagic fever (VHF) cases among febrile patients. To assess exposure to Lassa virus and other viral pathogens, we conducted a retrospective cross-sectional seroprevalence study in Forest Guinea (Guéckédou and N’Zérékoré). Lassa virus seroprevalence was 56.0% in the Guéckédou study group and 29.8% in the N’Zérékoré study group. Seropositivity increased with age in both study groups, suggesting cumulative exposure. Samples from Guéckédou laboratory were also tested for other pathogens, and antibodies against Marburg virus (5.8%), Zika virus (5.4%) and Crimean-Congo haemorrhagic fever virus (1.2%) were detected.