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Abstract: In Africa and the Arabian Peninsula, outbreaks of Rift Valley fever (RVF) are characterized by abortions in gestating animals and high mortality rates among domestic ruminants. An immunization program using a formalin-inactivated vaccine was initiated in Mozambique in 2002 to control RVF in cattle. In this intervention, the vaccine must be transported for more than a week within the country before it can be administered to the animals, and it is practically impossible to maintain low storage temperatures during that time. Here, we evaluated the influence of transportation conditions on the efficacy of the vaccine. Sixty-three previously unvaccinated and RVF virus seronegative cattle were divided into four groups, which were given vaccine that had been stored for 1 week at 4°C (n =9, group A), at 25°C (n =8, group B), or alternating between 4 and 25°C (n =8, group C), or under the temperature conditions ordinarily occurring during transportation within Mozambique (n =38, group D). The antibody responses induced were monitored for 6–9 months and in some animals up to 21 months. Two immunizations (3 weeks apart) with the formalin-inactivated vaccine induced a long-lasting neutralizing antibody response that was still detectable up to 21 months later. The antibody titers in the animals did not differ significantly between the temperature-assigned vaccine groups A, B, and C, whereas they were significantly higher in group D. These results show that the formalin-inactivated RVF virus vaccine is stable, and, importantly, it is not adversely affected by the variation in temperature that ordinarily occurs during transport within Mozambique. [Copyright &y& Elsevier]

Background: HCV infections can now be completely cured, thanks to the currently marketed direct-acting antivirals (DAAs). It is known that HCV patients carry viral populations with baseline polymorphisms and/or mutations that make them resistant against some of these DAAs, which can negatively impact the patient's treatment outcome. Using complete HCV coding sequences isolated from 1,306 treatment-naive patients of genotypes (GTs) 1, 2, 3, 4 and 6 from around the globe, we studied the prevalence of baseline resistance-associated polymorphisms (RAPs) and resistance mutations (RMs) against DAAs that are currently on the market or in clinical trials., Methods: The HCV genome sequences used in this study were retrieved from the NCBI database. RAPs and RMs, with reference to HCV GT1a, were identified using the HCV Geno2pheno web server., Results: Nearly 50% of the total amino acid positions (including NS3 protease, NS5A and NS5B) studied are baseline polymorphisms that differentiated one GT from the rest. A proportion of these baseline polymorphisms and baseline non-polymorphic RMs could confer a significant increase in resistance against DAAs., Conclusions: In this study, we show the presence and prevalence of RAPs and RMs in DAA treatment-naive patients against currently used DAAs or DAAs in clinical trials. Our study suggests that RAPs and RMs profiling of HCV patients should be performed before the start of the therapy. Our results should be relevant especially in low- and middle-income countries, where the patients have a large variation of GTs and subtypes, and where the generic HCV treatment is now increasingly available.