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Large-scale surveillance is crucial for understanding the evolution and the emergence of avian influenza viruses ( AIVs) in endemic areas. Circulation of highly pathogenic avian influenza ( HPAI) subtype H5N1 is continuously causing significant economic losses to the Egyptian poultry industry and is a threat to public health. In this report, a HPAI H5N1 strain (A/chicken/Egypt/Fadllah-7/2014) was detected from a vaccinated flock showing clinical signs of infection. Genetic characterization of the isolate indicated a high level of nucleotide identity (95-98%) with variant and classical groups of H5N1. Moreover, multiple-nucleotide and amino acid alignments revealed several prominent and characteristic substitutions in the surface glycoprotein, which may have biological relevance to the pathobiology of the virus. Phylogenetic analysis demonstrated that the reported isolate closely relates to H5N1 AIVs subclade 2.2.1.1 in spite of no reports of this subclade since 2011 from AI reported cases in Egyptian avian species. In conclusion, our results highlight the re-emergence of a novel H5N1 AIV variant subclade 2.2.1.1 that could escape immunity induced by vaccines. This discovery illustrates the importance of continuous monitoring of poultry in this country for controlling AIV including identifying sources of vaccine seed viruses. [ABSTRACT FROM AUTHOR]

Abortions cause heavy economic losses for the bovine sector. The use of a standardized panel of analyses covering a large spectrum of pathogens responsible of abortion in cattle allowed demonstrating the direct involvement of at least one pathogen in 57% of analysed abortions in the southern part of Belgium. This result suggests a margin of improvement in the diagnostic efficacy. In order to evaluate the interest to broaden the list of pathogens included in the panel of analyses, the implication of bovine herpesvirus 4 (Bo HV-4) in abortion was assessed by two different studies. In the first study, coupled serology was performed after abortion on 714 dams to identify specific seroconversion against Bo HV-4. The overall seroconversion in cows was 19.5%, with a higher frequency in primiparous compared to multiparous females. In addition, the type of breed (beef cattle) and the time period from the fourth quarter 2008 until the last quarter 2009 were significantly related to the seroconversion of cows. The second study investigated the virus ability to infect the foetus. In this study, 368 cases of bovine abortions were specifically tested for Bo HV-4, using PCR on foetus tissues and ELISA on dam and foetus sera. The results showed a maternal seroprevalence of 64.7%, a foetal seroprevalence of 0.8% and a PCR prevalence in foetuses of 1.1%, demonstrating the ability of Bo HV-4 to infect the foetus. [ABSTRACT FROM AUTHOR]

Reproductive and urinary tract abnormalities are a cause of infertility, reproductive inefficiency, and economic losses in goats. The aim of this study was to investigate the occurrence and nature of reproductive and urinary tract abnormalities encountered in female goats slaughtered at Nyagatare abattoir in the Eastern Province of Rwanda. Reproductive and urinary organs from 369 female goat carcasses were opened by incision and then given a thorough macroscopic examination by visually inspecting and palpating for evidence of abnormalities. The results showed that there was an overall occurrence of 7.8% reproductive organ/tract abnormalities and 10.6% urinary organ/tract abnormalities. Ovarian hypoplasia was the reproductive abnormality with the highest overall occurrence (32.3%) and renal calculi were the urinary organ abnormality with the highest occurrence (38.1%). 95.2% of the reproductive organ/tract abnormalities observed usually result in infertility and 91.3% of the urinary organ/tract abnormalities observed result in economic losses through condemnation of kidneys at slaughter. The high incidence of the observed urinary organ/tract abnormalities represents a potential public health challenge. There was no significant difference in the occurrence of reproductive organ/tract abnormalities according to breed (p > 0.05, n = 31). There was also no significant difference in the occurrence of urinary organ abnormalities according to breed (p > 0.05, n = 42). [ABSTRACT FROM AUTHOR]

The article presents the author's evaluation on studies about stochastic assessment of economic losses that is associated with hurricane hazard for whiteleg shrimp Litopenaeus vannamei that is cultivated form a floating cages in northwestern Mexico. These include the discontradiction of the results of studies regarding possible rejection of higher prices of shrimp in November compensating for the risk of hurricane impact and the validity of using the suggested intensive rearing techniques.

Porcine reproductive and respiratory syndrome virus ( PRRSV) is the causative agent of PRRS, the most significant infectious disease currently affecting swine industry worldwide. In the United States alone, the economic losses caused by PRRS amount to more than 560 million US dollars every year. Due to immune evasion strategies and the antigenic heterogeneity of the virus, current commercial PRRSV vaccines (killed-virus and modified-live vaccines) are of unsatisfactory efficacy, especially against heterologous infection. Continuous efforts have been devoted to develop better PRRSV vaccines. Experimental PRRSV vaccines, including live attenuated vaccines, recombinant vectors expressing PRRSV viral proteins, DNA vaccines and plant-made subunit vaccines, have been developed. However, the genetic and antigenic heterogeneity of the virus limits the value of almost all of the PRRSV vaccines tested. Developing a universal vaccine that can provide broad protection against circulating PRRSV strains has become a major challenge for current vaccine development. This paper reviews current status of PRRSV vaccine development and discusses strategies to develop a universal PRRSV vaccine. [ABSTRACT FROM AUTHOR]