Genome sequences of seven foot-andmouth disease virus isolates collected from serial samples from one persistently infected carrier cow in Vietnam

Several foot-and-mouth disease virus (FMDV) carrier cattle were identified in Vietnam by the recovery of infectious virus from oropharyngeal fluid. This report contains the first near-complete genome sequences of seven viruses from sequential samples from one carrier animal collected over the course of 1 year. The characterization of within-host viral evolution has implications for FMDV control strategies

Phylodynamics of foot-and-mouth disease virus O/PanAsia in Vietnam 2010-2014

© 2017 The Author(s). Foot-and-mouth disease virus (FMDV) is endemic in Vietnam, a country that plays an important role in livestock trade within Southeast Asia. The large populations of FMDV-susceptible species in Vietnam are important components of food production and of the national livelihood. In this study, we investigated the phylogeny of FMDV O/PanAsia in Vietnam, reconstructing the virus' ancestral host species (pig, cattle or buffalo), clinical stage (subclinical carrier or clinically affected) and geographical location. Phylogenetic divergence time estimation and character state reconstruction analyses suggest that movement of viruses between species differ. While inferred transmissions from cattle to buffalo and pigs and from pigs to cattle are well supported, transmission from buffalo to other species, and from pigs to buffalo may be less frequent. Geographical movements of FMDV O/PanAsia virus appears to occur in all directions within the country, with the South Central Coast and the Northeast regions playing a more important role in FMDV O/PanAsia spread. Genetic selection of variants with changes at specific sites within FMDV VP1 coding region was different depending on host groups analyzed. The overall ratio of non-synonymous to synonymous nucleotide changes was greater in pigs compared to cattle and buffalo, whereas a higher number of individual amino acid sites under positive selection were detected in persistently infected, subclinical animals compared to viruses collected from clinically diseased animals. These results provide novel insights to understand FMDV evolution and its association with viral spread within endemic countries. These findings may support animal health organizations in their endeavor to design animal disease control strategies in response to outbreaks

Association between vitamin D insufficiency and tuberculosis in a vietnamese population

<p>Abstract</p> <p>Background</p> <p>Recent <it>in vitro </it>evidence suggests a link between vitamin D status and the risk of tuberculosis (TB). This study sought to examine the association between vitamin D status, parathyroid hormone (PTH) and the risk of TB in a Vietnamese population.</p> <p>Methods</p> <p>The study was designed as a matched case-control study, which involved 166 TB patients (113 men and 53 women), who were age-and-sex matched with 219 controls (113 men and 106 women). The average age of men and women was 49 and 50, respectively. TB was diagnosed by the presence of acid-fast bacilli on smears from sputum, and the isolation of <it>M. tuberculosis</it>. All patients were hospitalized for treatment in a TB specialist hospital. Controls were randomly drawn from the general community within the Ho Chi Minh, Vietnam. 25-hydroxyvitamin D [25(OH)D] and PTH was measured prior to treatment by an electrochemiluminescence immunoassay (ECLIA) on a Roche Elecsys. A serum level of 25(OH)D below 30 ng/mL was deemed to be vitamin D insufficient.</p> <p>Results</p> <p>The prevalence of vitamin D insufficiency was 35.4% in men with TB and 19.5% in controls (<it>P </it>= 0.01). In women, there were no significant differences in serum 25(OH)D and serum PTH levels between TB patients and controls. The prevalence of vitamin D insufficiency in women with TB (45.3%) was not significantly different from those without TB (47.6%; <it>P </it>= 0.91). However, in both genders, serum calcium levels in TB patients were significantly lower than in non-TB individuals. Smoking (odds ratio [OR] 1.25; 95% confidence interval [CI] 1.10 - 14.7), reduced 25(OH)D (OR per standard deviation [SD]: 1.14; 95% CI 1.07 - 10.7) and increased PTH (OR per SD 1.13; 95% CI 1.05 - 10.4) were independently associated with increased risk of TB in men.</p> <p>Conclusion</p> <p>These results suggest that vitamin D insufficiency was a risk factor for tuberculosis in men, but not in women. However, it remains to be established whether the association is a causal relationship.</p

Site-specific substitution (Q172R) in the VP1 protein of FMDV isolates collected from asymptomatic carrier ruminants in Vietnam

The epidemiological significance of asymptomatic persistent foot-and-mouth disease virus (FMDV) infection in carrier animals, specifically its ability to seed new clinical outbreaks, is undetermined, and consistent viral determinants of FMDV persistence have not been identified. We analyzed 114 FMDV O/ME-SA/PanAsia VP1 sequences from naturally infected animals in Vietnam, of which 31 were obtained from persistently infected carrier animals. A site-specific substitution was identified at VP1 residue 172 where arginine was present in all 31 of the carrier-associated viruses, whereas outbreak viruses typically contained glutamine. Additionally, we characterized multiple viruses from a single persistently infected animal that were collected over the course of eight months and at multiple distinct anatomic sites (larynx, dorsal soft palate and dorsal nasopharynx). This work sheds new light on naturally occurring viral mutations within the host and provides a basis for understanding the viral evolution and persistence mechanisms of FMDV