Outbreaks of emerging coronaviruses in the past two decades and the current pandemic of a novel coronavirus (SARS-CoV-2) that emerged in China highlight the importance of this viral family as a zoonotic public health threat. To gain a better understanding of coronavirus presence and diversity in wildlife at wildlife-human interfaces in three southern provinces in Viet Nam 2013-2014, we used consensus Polymerase Chain Reactions to detect coronavirus sequences. In comparison to previous studies, we observed high proportions of positive samples among field rats (34.0%, 239/702) destined for human consumption and insectivorous bats in guano farms (74.8%, 234/313) adjacent to human dwellings. Most notably among field rats, the odds of coronavirus RNA detection significantly increased along the supply chain from field rats sold by traders (reference group; 20.7% positivity, 39/188) by a factor of 2.2 for field rats sold in large markets (32.0%, 116/363) and 10.0 for field rats sold and served in restaurants (55.6%, 84/151). Coronaviruses were also detected in rodents on the majority of wildlife farms sampled (60.7%, 17/28). These coronaviruses were found in the Malayan porcupines (6.0%, 20/331) and bamboo rats (6.3%, 6/96) that are raised on wildlife farms for human consumption as food. We identified six known coronaviruses in

51Outbreaks of emerging coronaviruses in the past two decades and the current pandemic 52 of a novel coronavirus (SARS-CoV-2) that emerged in China highlight the importance of this 53 viral family as a zoonotic public health threat. To gain a better understanding of coronavirus 54 presence and diversity in wildlife at wildlife-human interfaces in three southern provinces in Viet 55Nam 2013-2014, we used consensus Polymerase Chain Reactions to detect coronavirus 56 sequences. In comparison to previous studies, we observed high proportions of positive samples 57 among field rats (34.0%, 239/702) destined for human consumption and insectivorous bats in 58 guano farms (74.8%, 234/313) adjacent to human dwellings. Most notably among field rats, the 59 odds of coronavirus RNA detection significantly increased along the supply chain from field rats 60 sold by traders (reference group; 20.7% positivity, 39/188) by a factor of 2.2 for field rats sold in 61 large markets (32.0%, 116/363) and 10.0 for field rats sold and served in restaurants (55.6%, 62 84/151). Coronaviruses were detected in the majority of wildlife farms (60.7%, 17/28) and in the 63 Malayan porcupines (6.0%, 20/331) and bamboo rats (6.3%, 6/96) that are farmed. We identified 64 six known coronaviruses in bats and rodents, clustered in three Coronaviridae genera, including 65 the Alpha-, Beta-, and Gammacoronaviruses. Our analysis also suggested either mixing of 66 animal excreta in the environment or interspecies transmission of coronaviruses, as both bat and 67 avian coronaviruses were detected in rodent feces in the trade. The mixing of multiple 68 coronaviruses, and their apparent amplification along the wildlife supply chain into restaurants, 69 suggests maximal risk for end consumers and likely underpins the mechanisms of zoonotic 70 spillover to people. 71 72

SUMMARYPorcine reproductive and respiratory syndrome (PRRS) outbreaks in pigs are associated with increased susceptibility of pigs to secondary bacterial infections, including Streptococcus suis – an important zoonotic pathogen causing bacterial meningitis in humans. This case-control study examined the association between human S. suis infection and PRRS outbreaks in pigs in northern Vietnam. We included 90 S. suis case-patients and 183 non-S. suis sepsis controls from a referral hospital in Hanoi in 2010, a period of major PRRS epizootics in Vietnam. PRRS exposure was determined using data from the National Centre of Veterinary Diagnosis. By univariate analysis, significantly more S. suis patients were reported residing in or adjacent to a PRRS district compared to controls [odds ratio (OR) 2·82, 95% confidence interval (CI) 1·35–5·89 and OR 3·15, 95% CI 1·62–6·15, respectively]. Only residency in adjacent districts remained significantly associated with risk of S. suis infection after adjusting for sex, occupation, and eating practices. SaTScan analysis showed a possible cluster of S. suis infection in humans around PRRS confirmed locations during the March–August period. The findings indicate an epidemiological association between PRRS in pigs and S. suis infections in humans. Effective strategies to strengthen control of PRRS in pigs may help reduce transmission of S. suis infection to humans.

Porcine epidemic diarrhea virus (PEDV) has emerged in Vietnam since 2009. Herein, full-length genome sequences are reported for three PEDV isolates from pigs displaying severe diarrhea from farms located in northern and southern provinces of Vietnam. The results provide more understanding of the molecular characteristics of PEDV in Vietnam.

The mosquito Aedes aegypti is a transmission vector for dangerous epidemic diseases in humans. Insecticides have been used as the most general vector control method in the world. However, Ae. aegypti have developed many resistant mechanisms such as reduced neuronal sensitivity to insecticides (target-site resistance), enhanced insecticide metabolism (metabolic resistance), altered transport, sequestration, and other mechanisms. It has become a major problem for vector control programs. Transcriptome sequencing and bioinformatic analysis were used to compare transcription levels between a susceptible strain (Bora7) and a resistant strain (KhanhHoa7) collected from the field. A total of 161 million Illumina reads, including 66,076,678 reads from the Bora7 strain and 69,606,654 reads from the KhanhHoa7 strain, were generated and assembled into 11,174 genes. A comparison of the KhanhHoa7 transcriptome to that of Bora7 showed 672 upregulated genes and 488 downregulated genes. We identified the highly upregulated genes: cytochrome P450 4C1, 4C3, 4C21, 4D1, 4D1 isoform X2, 4D2, 4D2 isoform X2, 4G15, 6A2, 6A8, 6D3, and 9E2; Glutathione S transferase (GST1), UGT1-3, 1-7, 2B15, and 2B37; binding cassette transporter (ABC) transporter F family member 4 and ABC transporter G family member 20. Interestingly, there was a significant increase in the expression of the genes such as CYP9E2 (8.3-fold), CYP6A8 (5.9-fold), CYP6D3 (5.4-fold), CYP4C21 (5.4-fold), CYP4G15 (5.2-fold), GST1 (3.5-fold), and ABC transporter 4 (2.1-fold). Our results suggested a potential relationship between the expression of the genes in metabolic processes and insecticide resistance in the studied strain. These results may contribute to the understanding of the mechanisms of insecticide resistance in Ae. aegypti.

Porcine epidemic diarrhea virus (PEDV) first emerged in Vietnam in 2009. In this study, the complete genomes of three Vietnamese PEDV isolates were characterized. These three isolates were isolated from 3-day-old pigs experiencing diarrhea. Two isolates were from swine farms in the south, and the other was from northern Vietnam. The whole genome sequences of these isolates are 28,035 nucleotides in length and have characteristics similar to those of other PEDV isolates. All three Vietnamese PEDV isolates share 99.8 % and 99.6 % sequence identity at the nucleotide and amino acid level, respectively, and have insertions of four amino acids (GENQ) and one amino acid (N) at positions 56-59 and 140, respectively, and one deletion of two amino acids (DG) at positions 160-161. Phylogenetic analysis based on the whole genome revealed that the three Vietnamese PEDV isolates are grouped together with new variants from China from 2011 to 2012 and are genetically distinct from US isolates and the classical PEDV variant. The results suggest that Vietnamese PEDV isolates are new variants, as evidenced by their genetic composition of insertions and a deletion in the spike gene, and they might have originated from the same ancestor as the Chinese PEDV strain. This study provides a better understanding of the molecular characteristics of PEDV in Vietnam.

The 3ABC ELISA identified field and experimentally infected animals, as well as vaccinated and subsequently infected animals. Diagnostic sensitivity and specificity estimates for other FMD NSP tests are comparable with the results obtained in this study. This NSP ELISA was found to be 'fit for purpose' as a screening assay at the herd level to detect viral infection and also to substantiate absence of infection.

Biotechnological applications of cytochromes P450 show difficulties, such as low activity, thermal and/or solvent instability, narrow substrate specificity and redox partner dependence. In an attempt to overcome these limitations, an exploitation of novel thermophilic P450 enzymes from nature via uncultured approaches is desirable due to their great advantages that can resolve nearly all mentioned impediments. From the metagenomics library of the Binh Chau hot spring, an open reading frame (ORF) encoding a thermostable cytochrome P450—designated as P450-T3—which shared 66.6% amino acid sequence identity with CYP109C2 of Sorangium cellulosum So ce56 was selected for further identification and characterization. The ORF was synthesized artificially and heterologously expressed in Escherichia coli C43(DE3) using the pET17b system. The purified enzyme had a molecular weight of approximately 43 kDa. The melting temperature of the purified enzyme was 76.2 °C and its apparent half-life at 60 °C was 38.7 min. Redox partner screening revealed that P450-T3 was reduced well by the mammalian AdR-Adx4-108 and the yeast Arh1-Etp1 redox partners. Lauric acid, palmitic acid, embelin, retinoic acid (all-trans) and retinoic acid (13-cis) demonstrated binding to P450-T3. Interestingly, P450-T3 also bound and converted testosterone. Overall, P450-T3 might become a good candidate for biocatalytic applications on a larger scale.