Efficacy of a Modified Live Virus Vaccine against Porcine Reproductive and Respiratory Syndrome Virus 1 (PRRSV-1) Administered to 1-Day-Old Piglets in Front of Heterologous PRRSV-1 Challenge.

PRRSV is one of the most important viruses in the global swine industry and is often controlled by the use of modified live virus (MLV) vaccines. This study assessed the impact of a PRRSV-1 MLV vaccine applied to 1-day-old piglets challenged on day 28 of life with a PRRSV-1 field isolate (AUT15-33). Twenty-one piglets were vaccinated within 24 h of birth (T02), whereas 20 piglets were left unvaccinated (T01). Necropsy was performed two weeks post-challenge. Comparing the two groups, T02 piglets showed significantly higher (p = 0.017) average daily weight gain. In addition, significantly lower (p < 0.0001) PRRSV RNA loads were measured in serum of T02 piglets at all investigated time points. All T01 piglets were viremic and shed virus in nasal swabs, whereas only 71.4% and 38.1% of the T02 group were viremic or shed virus, respectively. Piglets from T02 had significantly higher numbers (p < 0.0001) of IFN-γ producing lymphocytes compared to T01. At necropsy, differences in gross and histologic lung lesions were statistically significant (p = 0.012 and p < 0.0001, respectively) between the two groups. Hence, this MLV vaccine administered to 1-day-old piglets was able to protect piglets against PRRSV infection at weaning.

[Can we train the chain of survival while playing? Validation of the tool «Rescube¼]. / ¿Podemos enseñar la «cadena de supervivencia¼ jugando? Validación de la herramienta «Rescube¼.

PURPOSE: To validate the content and adequacy of the «Rescube¼ training material that includes adapted information from the chain of survival. MATERIAL AND METHODS: The study included three steps: (i)material development by 7 experts, following Delphi method; (ii)assessment of training material by 11 experts by means of a Likert score and calculation of content validity; and (iii)pilot study in two groups of 5 to 8years-old: Rescube group (GR; n=60) and Traditional group (GT; n=60). GR was trained with Rescube and a Teddy bear, while GT was traditionally trained with a pediatric manikin. Participants were individually assessed at baseline, and one week and one month after training. RESULTS: All content validity indexes calculated are above the recommended cut-off for analysis with more than 9 experts (≥0,80). Children's learning results were positive, with percentages equal or higher than 80% in all registered variables at the first (one week) evaluation and equal or higher than 67% when evaluated one month after training. No significant differences were detected between groups. CONCLUSION: The Rescube training tool based on infantile pictures is valid and useful to train young schoolchildren in the chain of survival.

Vaccination of horses with a recombinant modified vaccinia Ankara virus (MVA) expressing African horse sickness (AHS) virus major capsid protein VP2 provides complete clinical protection against challenge.

African horse sickness virus (AHSV) is an arthropod-borne pathogen that infects all species of equidae and causes high mortality in horses. Previously, a recombinant modified vaccinia Ankara (MVA) virus expressing the protein VP2 of AHSV serotype 4 was shown to induce virus neutralising antibodies in horses and protected interferon alpha receptor gene knock-out mice (IFNAR -/-) against virulent AHSV challenge. This study builds on the previous work, examining the protective efficacy of MVA-VP2 vaccination in the natural host of AHSV infection. A study group of 4 horses was vaccinated twice with a recombinant MVA virus expressing the major capsid protein (VP2) of AHSV serotype 9. Vaccinated animals and a control group of unvaccinated horses were then challenged with a virulent strain of AHSV-9. The vaccinated animals were completely protected against clinical disease and also against viraemia as measured by standard end-point dilution assays. In contrast, all control horses presented viraemia after challenge and succumbed to the infection. These results demonstrate the potential of recombinant MVA viruses expressing the outer capsid VP2 of AHSV as a protective vaccine against AHSV infection in the field.

Schoolchildren as life savers: at what age do they become strong enough?

OBJECTIVE: It is not clear when schoolchildren become enough strong to perform good quality chest compressions (CC). Our purpose was to assess CC quality in schoolchildren. METHODS: 721 children, 10-15 years old (YO) participated in 1 h hands-on training session. Subjects were tested during performing 2 min of continuous CC by means of Laerdal Resusci Anne(®) with Skillreporter(®), without feedback. RESULTS: Mean compression depth (MCD) increased with age, from 30.7 mm in 10YO to 42.9 mm in 15YO (p<0.05) and was related to height, weight, and BMI. Boys delivered significantly deeper CC than girls in the 10, 13, 14 and 15YO groups (p<0.001). The percentage of children who achieved the MCD goal (50-60 mm), increased with age, from 0.0% at 10 years to 26.5% at 15 years (p<0.001). Mean compression rate (MCR) ranged from 121 min(-1) in 15YO to 134 min(-1) in 12YO. The percentage of children who achieved a CC rate inside the goal (100-120 min(-1)), ranged from 20.3% in 11YO to 31.0% in 15YO. Correct CC fraction was low and ranged from 2% in the 10YO to 22% in the 15YO (p<0.05). Children older than 13YO obtained better results than younger ones for all analyzed variables (p<0.001). Performance decreased with time: 12% of children achieved >50% of correct CC fraction in first minute, while only 5% did it in second minute (p<0.001). CONCLUSIONS: In schoolchildren, age, sex and anthropometry are significant CPR quality factors. Although quality increases with age, their global performance is poor. Thirteen years is the minimum age to be able to achieve a minimum CPR quality similar to the one adult possess. CPR performance in schoolchildren significantly deteriorates within 60 s.

Catalytic efficiency and phenotype of HIV-1 proteases encoding single critical resistance substitutions.

We have shown that a bacteriophage lambda genetic screen system may be useful in predicting the activity and phenotype of HIV-1 protease in the course of viral infection and antiretroviral therapy. This simple and rapid genetic screening system has been used here to characterize HIV-1 proteases encoding single primary resistance substitutions. Except for proteases with amino acid changes at positions 46 and 84, proteases containing single-resistance substitutions displayed a lower catalytic efficiency than the WT enzyme. Single mutants could be identified by their efficiency, demonstrating that modest differences in protease activity can be monitored with this simple assay. Overall, drug susceptibility could be reduced by introduction of single mutations. However, high-level protease inhibitor (PI) resistance was only achieved by multiple mutated proteases. The small but reproducible increase in resistance displayed by single mutants also demonstrated the ability of this genetic screen system for detecting minor reductions in drug susceptibility. These results show that the bacteriophage lambda genetic screen system used here is a useful tool in the analysis of specific contribution of mutations in the HIV protease-coding region or in specific cleavage sites that affect the process of PI resistance.