Non-Attenuation Of Highly Pathogenic Avian Influenza H5N1 By Laboratory Exposure To Ultraviolet Rays

Avian influenza H5N1 represents one of the most researched viruses in laboratories world-wide in recent times with regards to its epidemiology, ecology, biology and geography. The virus has caused 409 human cases and 256 human fatalities to date. Some laboratory activities and other lab relatedworks predispose certain workers to exposure to this virus. In this work, we assessed the effect of exposure of HPAI infective allantoic fluid to ultraviolet rays for between 15 and 180 minutes. No significant difference was found between the unexposed and exposed viruses. The ability of the virus to haemagglutinate chicken red blood cells, the haemagglutination titre and its pathogenicity in embryonating eggs did not change despite this prolong exposure to UV-light. We call for caution in the handling of HPAI viruses in laboratory inside the microbiological safety cabinet despite sterilization using UV-light

Genetic variant of canine distemper virus from clinical cases in vaccinated dogs in South Africa

Canine distemper virus (CDV) is a highly contagious viral pathogen of worldwide distribution that can cause lethal disease in domestic dogs and other members of the family Canidae. Genetic diversity is found among reference strains and isolates of CDV, mainly in the haemagglutinin (H) protein, and this may be associated with the increasing incidence of distemper in dogs. CDV was isolated in Vero cells expressing canine signalling lymphocyte activation molecule (Vero.DogSLAM) from peripheralblood mononuclear cells and spleen of clinically diseased, previously vaccinated South African dogs. Direct fluorescence antibody test and electronmicroscopy were used to confirm the isolation procedure. Subsequently, RT-PCR was performed on the cell culture isolates, the amplified products were purified and the complete H gene wassequenced and phylogenetically analysed. The H gene of vaccines in use in South Africa was also sequenced and comparative analyses performed. However, the sequences obtained from the sick dogs showed 100% nucleotide identity and was different to that found in virus strains used in vaccines and in isolates reported from other parts of the world in GenBank. The results suggest that a novel CDV lineage may be present in South Africa and we conclude that a recent reversion of vaccine virus to virulence was not the cause of the clinical signs seen in dogs with a previoushistory of vaccination

Characterization of transboundary foot-and-mouth disease viruses in nigeria and cameroon during 2016.

Continuous surveillance for foot-and-mouth disease (FMD) in endemic settings such as West Africa is imperative to support improved local and regional control plans, with the long-term goal of regional eradication. This paper describes the genetic characterization of FMD viruses (FMDV) obtained from outbreaks in Nigeria (n = 45) and Cameroon (n = 15) during 2016 and from archival samples (n = 3) retrieved from a 2014 outbreak in Nigeria. These viruses were analyzed in the context of previously published FMDV sequences from the region. Four FMDV serotypes: O, A, SAT1 and SAT2 were detected. Phylogenetic analyses of the VP1 coding sequences indicate the continuity of FMDV serotype O East Africa-3 (O/EA-3), serotype A AFRICA genotype G-IV (A/AFRICA/G-IV), and serotype South African Territories (SAT) 2 lineage VII (SAT2/VII). The FMDV SAT1 topotype X (SAT1/X), which emerged in Nigeria in 2015, continued to be associated with outbreaks in the region during 2016, and SAT1 is reported for the first time from Cameroon. Additionally, a re-emergence or re-introduction of the serotype O West Africa (O/WA) topotype in Nigeria is described herein. Our findings indicate a consistent, pan-serotypic relationship between FMDV strains detected in Cameroon and Nigeria. Additionally, FMDV strains from West Africa obtained in this study were genetically related to those occurring in East and North Africa. These phylogenetic relationships suggest that animal movements (pastoralism and/or trade) are important factors for virus spread across the African continent. These data provide critical baselines which are a necessary component of Stage 0 and 1 of the Progressive Control Pathway of FMD (PCP-FMD). Specifically, characterizing the existing virus strains (risk) provides the basis for the comprehensive risk-based control plan which is the requisite criteria for Nigeria's transition to Stage 2 of PCP-FMD, and for coordinated regional control of FMD