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Surveillance, isolation and genomic characterization of Pteropine orthoreovirus of probable bat origin among patients with acute respiratory infection in Malaysia

Tee KK, Chan PQ, Loh AM, Singh S, Teo CH, Iyadorai T, et al.

J Med Virol, 2023 Feb;95(2):e28520.
PMID: 36691929 DOI: 10.1002/jmv.28520

Pteropine orthoreovirus (PRV), an emerging bat-borne virus, has been linked to cases of acute respiratory infections (ARI) in humans. The prevalence, epidemiology and genomic diversity of PRV among ARI of unknown origin were studied. Among 632 urban outpatients tested negative for all known respiratory viruses, 2.2% were PRV-positive. Patients mainly presented with moderate to severe forms of cough, sore throat and muscle ache, but rarely with fever. Phylogenetic analysis revealed that over 90% of patients infected with the Melaka virus (MelV)-like PRV, while one patient infected with the Pulau virus previously found only in fruit bats. Human oral keratinocytes and nasopharyngeal epithelial cells were susceptible to clinical isolates of PRV, including the newly isolated MelV-like 12MYKLU1034. Whole genome sequence of 12MYKLU1034 using Nanopore technique revealed a novel reassortant strain. Evolutionary analysis of the global PRV strains suggests the continuous evolution of PRV through genetic reassortment among PRV strains circulating in human, bats and non-human primate hosts, creating a spectrum of reassortant lineages with complex evolutionary characteristics. In summary, the role of PRV as a common etiologic agent of ARI is evident. Continuous monitoring of PRV prevalence, pathogenicity and diversity among human and animal hosts is important to trace the emergence of novel reassortants.
Chania multitudinisentens gen. nov., sp. nov., an N-acyl-homoserine-lactone-producing bacterium in the family Enterobacteriaceae isolated from landfill site soil

Ee R, Madhaiyan M, Ji L, Lim YL, Nor NM, Tee KK, et al.

Int J Syst Evol Microbiol, 2016 Jun;66(6):2297-2304.
PMID: 26978486 DOI: 10.1099/ijsem.0.001025

Phylogenetic and taxonomic characterization was performed for bacterium RB-25T, which was isolated from a soil sample collected in a former municipal landfill site in Puchong, Malaysia. Growth occurred at 20-37 °C at pH 5-8 but not in the presence of 9 % (w/v) NaCl or higher. The principal fatty acids were C16:0, C18:1ω7c and summed feature 3 (C16:1ω7c and/or iso-C15:0 2-OH). Ubiquinone-8 was the only isoprenoid quinone detected. Polar lipid analysis revealed the presence of phospholipid, phosphoaminolipid, phosphatidylethanolamine, phosphatidylglycerol and one unidentified aminolipid. DNA G+C content was 50.9 mol% phylogenetic analysis based on 16S rRNA gene sequence showed that strain RB-25T formed a distinct lineage within the family Enterobacteriaceae of the class Gammaproteobacteria. It exhibited a low level of 16S rRNA gene sequence similarity with its phylogenetic neighbours Pantoea rwandensis LMG 26275T (96.6 %), Rahnella aquatilis CIP 78.65T (96.5 %), Pectobacterium betavasculorum ATCC 43762T (96.4 %), Pantoea rodasii LMG 26273T (96.3 %), Gibbsiella dentisursi NUM 1720T (96.3 %) and Serratia glossinae C1T (96.2 %). Multilocus sequence analyses based on fusA, pyrG, rplB, rpoB and sucA sequences showed a clear distinction of strain RB-25T from the most closely related genera. Isolate RB-25T could also be distinguished from members of these genera by a combination of the DNA G+C content, respiratory quinone system, fatty acid profile, polar lipid composition and other phenotypic features. Strain RB-25T represents a novel species of a new genus, for which the name Chaniamultitudinisentens gen. nov., sp. nov. is proposed. The type strain is RB-25T (=DSM 28811T=LMG 28304T).
Fulltext Transcriptome analysis of Pseudomonas aeruginosa PAO1 grown at both body and elevated temperatures

Chan KG, Priya K, Chang CY, Abdul Rahman AY, Tee KK, Yin WF

PeerJ, 2016;4:e2223.
PMID: 27547539 DOI: 10.7717/peerj.2223

Functional genomics research can give us valuable insights into bacterial gene function. RNA Sequencing (RNA-seq) can generate information on transcript abundance in bacteria following abiotic stress treatments. In this study, we used the RNA-seq technique to study the transcriptomes of the opportunistic nosocomial pathogen Pseudomonas aeruginosa PAO1 following heat shock. Samples were grown at both the human body temperature (37 °C) and an arbitrarily-selected temperature of 46 °C. In this work using RNA-seq, we identified 133 genes that are differentially expressed at 46 °C compared to the human body temperature. Our work identifies some key P. aeruginosa PAO1 genes whose products have importance in both environmental adaptation as well as in vivo infection in febrile hosts. More importantly, our transcriptomic results show that many genes are only expressed when subjected to heat shock. Because the RNA-seq can generate high throughput gene expression profiles, our work reveals many unanticipated genes with further work to be done exploring such genes products.
Fulltext Description of the COVID-19 epidemiology in Malaysia

Md Nadzri MN, Md Zamri ASS, Singh S, Sumarni MG, Lai CH, Tan CV, et al.

Front Public Health, 2024;12:1289622.
PMID: 38544725 DOI: 10.3389/fpubh.2024.1289622

INTRODUCTION: Since the COVID-19 pandemic began, it has spread rapidly across the world and has resulted in recurrent outbreaks. This study aims to describe the COVID-19 epidemiology in terms of COVID-19 cases, deaths, ICU admissions, ventilator requirements, testing, incidence rate, death rate, case fatality rate (CFR) and test positivity rate for each outbreak from the beginning of the pandemic in 2020 till endemicity of COVID-19 in 2022 in Malaysia.
METHODS: Data was sourced from the GitHub repository and the Ministry of Health's official COVID-19 website. The study period was from the beginning of the outbreak in Malaysia, which began during Epidemiological Week (Ep Wk) 4 in 2020, to the last Ep Wk 18 in 2022. Data were aggregated by Ep Wk and analyzed in terms of COVID-19 cases, deaths, ICU admissions, ventilator requirements, testing, incidence rate, death rate, case fatality rate (CFR) and test positivity rate by years (2020 and 2022) and for each outbreak of COVID-19.
RESULTS: A total of 4,456,736 cases, 35,579 deaths and 58,906,954 COVID-19 tests were reported for the period from 2020 to 2022. The COVID-19 incidence rate, death rate, CFR and test positivity rate were reported at 1.085 and 0.009 per 1,000 populations, 0.80 and 7.57%, respectively, for the period from 2020 to 2022. Higher cases, deaths, testing, incidence/death rate, CFR and test positivity rates were reported in 2021 and during the Delta outbreak. This is evident by the highest number of COVID-19 cases, ICU admissions, ventilatory requirements and deaths observed during the Delta outbreak.
CONCLUSION: The Delta outbreak was the most severe compared to other outbreaks in Malaysia's study period. In addition, this study provides evidence that outbreaks of COVID-19, which are caused by highly virulent and transmissible variants, tend to be more severe and devastating if these outbreaks are not controlled early on. Therefore, close monitoring of key epidemiological indicators, as reported in this study, is essential in the control and management of future COVID-19 outbreaks in Malaysia.