Comparative Analysis of Novel Strains of Porcine Astrovirus Type 3 in the USA

Porcine astrovirus type 3 (PoAstV3) has been previously identified as a cause of polioencephalomyelitis in swine and continues to cause disease in the US swine industry. Herein, we describe the characterization of both untranslated regions, frameshifting signal, putative genome-linked virus protein (VPg) and conserved antigenic epitopes of several novel PoAstV3 genomes. Twenty complete coding sequences (CDS) were obtained from 32 diagnostic cases originating from 11 individual farms/systems sharing a nucleotide (amino acid) percent identity of 89.74-100% (94.79-100%), 91.9-100% (96.3-100%) and 90.71-100% (93.51-100%) for ORF1a, ORF1ab and ORF2, respectively. Our results indicate that the 5'UTR of PoAstV3 is highly conserved highlighting the importance of this region in translation initiation while their 3'UTR is moderately conserved among strains, presenting alternative configurations including multiple putative protein binding sites and pseudoknots. Moreover, two predicted conserved antigenic epitopes were identified matching the 3' termini of VP27 of PoAstV3 USA strains. These epitopes may aid in the design and development of vaccine components and diagnostic assays useful to control outbreaks of PoAstV3-associated CNS disease. In conclusion, this is the first analysis predicting the structure of important regulatory motifs of neurotropic mamastroviruses, which differ from those previously described in human astroviruses.

Longitudinal piglet sampling in commercial sow farms highlights the challenge of PRRSV detection

BACKGROUND

Processing fluids (PF) and family oral fluids (FOF) are population-based surveillance samples collected from 2- to 5-day-old piglets and due-to-wean piglets, respectively. Although they are described for the surveillance of PRRSV in sows and piglet populations at processing and weaning, there is limited information on their use in commercial herds. This observational study described PRRSV RNA detection over time in PF, FOF, and piglet serum collected from farrowing groups in commercial breeding farms with the objective of achieving robust, practical, and effective PRRSV surveillance protocols. Weekly PF (an aggregate sample of all litters processed in a week from each room), and FOF (a convenience sample attempted from at least 20 individual litters in at least one farrowing room each week) samples were collected from six PRRSV-endemic commercial breeding herds for up to 38 weeks. A total of 561 PF room samples, 2400 individual litter FOF samples, and 600 serum samples (120 pools of 5 samples) were collected during the study period and tested for PRRSV RNA. Data were evaluated for patterns of PRRSV RNA detection by specimen within farms over time.

RESULTS

In particular, the detection of PRRSV was commonly sporadic over time within farms (weeks of PRRSV RNA negative results followed by one or more weeks of positive results); was often non-uniform within farms (negative and positive farrowing rooms at a given point in time); and PF and FOF testing results agreement was 75 and 80% at week and room level, respectively, demonstrating that both sampling methods could complement each other. Non-uniformity in PRRSV detection in rooms sampled within the same week and detection after ≥11 consecutive weeks of PRRSV negative PF and FOF results underline the challenge of consistently detecting the virus.

CONCLUSIONS

These results suggest that monitoring protocols for breeding herds attempting PRRSV control or elimination can use both PF and FOF to improve PRRSV detection in suckling pig populations.

[Level of noise at the workplace environment among physical education teachers in indoor bike classes]

OBJECTIVE

To analyze the level of noise at the workplace environment among Physical Education teachers during indoor bike classes and its association with some aspects of health.

METHODS

Cross-sectional study carried out in 15 different gyms with 15 teachers in Rio de Janeiro (Southeastern Brazil) in 2007. A standardized questionnaire, tested in relation to its replication, was used in order to find out the characteristics of the process and the way this job is organized, as well as complaints related to health reported by these teachers. The SRQ-20 (Self-Report Questionnaire) was utilized in order to verify the existence of minor psychiatric disturbances. The levels of sound pressure were measured by a portable appliance. The level of pressure was verified in dB(A) at equivalent energy levels (Leq) in different places of the room at different moments during the class. ANOVA, chi-square and Pearson's correlation analyses were performed.

RESULTS

The levels of sound pressure varied from 74.4 dB(A) to 101.6 dB(A). The results during the class were: a) warm-up (mean=88.45 dB(A)); b) main part (mean= 95.86 dB(A)); and, closure (mean= 85.12 dB(A)). The mean background noise was 66.89 dB(A)). There were significant differences (p<0.001) among the background noise levels within different moments of the class. The noise was not related to minor psychiatric disturbances.

CONCLUSIONS

Physical education professionals working with indoor bike classes are under high levels of sound pressure during their classes. This physical agent has been related to several health problems and should therefore be more controlled.