Background: The COVID-19 pandemic poses an unprecedented public health challenge in Malaysia. The impact of COVID-19 varies between countries, including geographically divided states within a country. The deadly transmission of COVID-19 has taken a heavy toll in Sabah, Malaysia’s third most populous state, contributing nearly 10% to the recorded national death toll as of 31 December 2022. Although several SARS-CoV-2 genome sequences have been analysed in Malaysia, molecular epidemiology data from Sabah focusing on the diversity and evolution of SARS-CoV-2 variants are still lacking. This study examines the major SARS-CoV-2 variants and emerging mutations from Sabah, the Malaysian Borneo, which is geographically divided from West Malaysia by the South China Sea. Methods: A total of 583 COVID-19 samples were subjected to whole genome sequencing and analysed with an additional 1123 Sabah COVID-19 sequences retrieved from the GISAID EpiCoV consortium. Nextclade and Pangolin were used to classify these sequences according to the clades and lineages. To determine the molecular evolutionary characteristics, Bayesian time-scaled phylogenetic analysis employing the maximum likelihood algorithm was performed on selected SARS-CoV-2 genome sequences, using the Wuhan-Hu-1 sequence as a reference. Results: Sabah was affected starting from the second COVID-19 wave in Malaysia, and the early sequences were classified under the O clade. The clade was gradually replaced during subsequent waves by G, GH, GK and GRA, with the latter being dominant as of December 2022. Phylogenetically, the Delta isolates in this study belong to the three main subclades 21A, 21J and 21I, while Omicron isolates belong to 21M, 21L and 22B. The time-scaled phylogeny suggested that SARS-CoV-2 introduced into Sabah originated from Peninsular Malaysia in early March 2020, and phylodynamic analysis indicated that increased viral spread was observed in early March and declined in late April, followed by an evolutionary stationary phase in June 2020. Conclusion: Continuous molecular epidemiology of SARS-CoV-2 in Sabah will provide a deeper understanding of the emergence and dominance of each variant in the locality, thus facilitating public health intervention measures.

Wastewater treatment has evolved from a pollution-control strategy to a resource recovery platform that supports circular economy principles and sustainable environmental management. Microbial communities play central roles in nutrient cycling, organic matter degradation, carbon sequestration and the removal of emerging contaminants throughout wastewater treatment processes. This review synthesizes current knowledge on microbial community dynamics in domestic, industrial and agricultural wastewater treatment systems, emphasizing their functional roles in biological nutrient removal, enhanced biological phosphorus removal and resource recovery. Recent advances in metagenomics, metatranscriptomics, metaproteomics, fluorescence in situ hybridization (FISH) and artificial intelligence have significantly improved the characterization and monitoring of wastewater microbiomes, enabling more efficient process optimization and predictive management. The review also discusses the growing importance of wastewater surveillance for monitoring antimicrobial resistance genes, pathogenic microorganisms and contaminants of emerging concern, highlighting their implications for environmental and public health. Emerging technologies, including bio-electrochemical systems, microbial fuel cells, immobilized microbial consortia and anaerobic resource recovery platforms, demonstrate considerable potential for improving energy efficiency and reducing greenhouse gas emissions while enhancing nutrient recovery. Despite substantial technological progress, challenges remain regarding large-scale implementation, operational stability, standardization of multi-omics approaches and integration of biological and engineering processes. Future wastewater treatment facilities are expected to function as integrated biorefineries that simultaneously recover water, nutrients, energy and valuable bioproducts while minimizing environmental impacts. Continued advances in microbial ecology, systems biology, artificial intelligence and process engineering will be essential for developing resilient, low-carbon wastewater treatment systems that support sustainable resource management and public health protection.

Caprine arthritis encephalitis (CAE) and peste des petits ruminants (PPR) are significant viral diseases impacting small ruminants, leading to substantial economic losses and posing a potential threat to livestock health. Although seroprevalence evidence of these viruses has been documented in ruminants, there is a lack of data regarding their presence among farmed deer in Malaysia. This preliminary study aimed to determine the seroprevalence and associated risk factors for CAEV and PPRV infections among deer in Malaysia. A total of ninety-two blood sera from an institutional deer farm were screened for CAEV and PPRV antibodies using commercially available indirect ELISA test kits. The results revealed 8.7% (95% CI = 4.47-16.23) apparent and 8.38% (95% CI = 3.72-16.7) true prevalence for CAEV and 4.35% (95% CI = 1.70-10.65) apparent and 3.99% (95% CI = 1.18-10.70) true seroprevalence for PPRV among deer. Univariable analysis indicated that age (χ² = 4.434, p = 0.707) and sex (χ² = 1.071, p = 0.377) were not significantly associated with CAEV seropositivity, while the herd group (χ² = 4.733, p = 0.053) showed a significant association. Conversely, PPR seroprevalence was higher in young deer (8.0%) compared to adults (2.69%), with female deer demonstrating a higher prevalence (5.36%) than males. Additionally, the older herd exhibited a higher true prevalence of PPR (5.07%) compared to the newer herd (2.32%). This study provides the first serological evidence of CAEV and PPRV among deer in Malaysia and justifies further epidemiological investigations in order to reduce the potential threat to animals.

Background: Hepatitis B virus (HBV) remains a major global health concern, particularly in developing countries, due to its ability to evade host immune defenses. The innate immune system serves as the first line of defense, restricting HBV and initiating adaptive immune responses for viral clearance. Both parenchymal and non-parenchymal liver cells express various pattern recognition receptors (PRRs), such as Toll-like receptors (TLRs), RIG-I-like receptors (RIG-I), melanoma differentiation-associated gene 5 (MDA-5), and nucleotide-binding oligomerization domain-like receptors (NLRs), which detect and respond to HBV. These PRRs mediate antiviral responses that suppress HBV replication and support its elimination. However, HBV has developed mechanisms to subvert these responses, notably by inactivating PRR signaling via viral proteins, enabling persistent infection. Chronic HBV infection arises from the innate immune system’s inability to control the virus in hepatocytes. Understanding PRR-mediated immunity and HBV evasion strategies is critical for developing effective immune-based therapies for both acute and chronic HBV infection.