Complex Virome in a Mesenteric Lymph Node from a Californian Sea Lion (Zalophus Californianus) with Polyserositis and Steatitis.

An emaciated subadult free-ranging California sea lion (Csl or Zalophus californianus) died following stranding with lesions similar to 11 other stranded animals characterized by chronic disseminated granulomatous inflammation with necrotizing steatitis and vasculitis, involving visceral adipose tissues in the thoracic and peritoneal cavities. Histologically, affected tissues had extensive accumulations of macrophages with perivascular lymphocytes, plasma cells, and fewer neutrophils. Using viral metagenomics on a mesenteric lymph node six mammalian viruses were identified consisting of novel parvovirus, polyomavirus, rotavirus, anellovirus, and previously described Csl adenovirus 1 and Csl bocavirus 4. The causal or contributory role of these viruses to the gross and histologic lesions of this sea lion remains to be determined.

Causes of swine polyserositis in a high-density breeding area in Italy.

We assessed the causes of polyserositis in pigs, categorized by causative agents and ages of animals affected. In a 3-y study, 246 pigs from 80 different farms with recurrent problems of polyserositis, in a high-density breeding area, were submitted for autopsy; 154 pigs with typical fibrinous serosal lesions were sampled for further bacterial and viral investigation. The most common gross lesions were pleuritis and pericarditis (141 of 154; 92%). The animals most affected were weaned pigs (139 of 154; 90%). Haemophilus parasuis and Mycoplasma hyorhinis were the most common bacteria detected and were present at the same rate (85 of 154; 55%). Other bacteria isolated were Streptococcus sp. (44 of 154; 29%), Pasteurella multocida (21 of 154; 14%), Escherichia coli (19 of 154; 12%), Actinobacillus pleuropneumoniae (7 of 154; 5%), and Trueperella pyogenes (4 of 154; 3%). Porcine reproductive and respiratory syndrome virus (PRRSV; 119 of 154; 77%) predominated among the viruses detected, followed, with lesser prevalence, by porcine circovirus 2 (40 of 154; 26%) and swine influenza A virus (19 of 154; 12%). Bacterial coinfection and coinfection of bacteria and viruses were common (128 of 154; 83%). A strong positive correlation was found between coinfection by H. parasuis and M. hyorhinis and also by H. parasuis with PRRSV.

Clinical spectrum of dengue fever in a tertiary care centre with particular reference to atypical presentation in the 2012 outbreak in Kolkata.

During the summer of 2012, dengue fever epidemic has emerged in Kolkata and spread throughout West Bengal. During the epidemic period, wide spectrum of atypical presentations of dengue fever has been observed. Here, in this study, the spectrum of dengue fever was analysed in 300 patients who were found to have dengue serology positive (NS1, IgM, IgG). The study was done in the department of medicine, RG Kar Medical College, Kolkata. The patients were classified according to age, gender, duration of symptoms on admission, associated comorbidities and coinfections, complications that developed after admission, the final outcome and duration till death after symptoms developed. The dengue fever cases started to appear from April but it attained its peak during August-September this year. All ages were affected but the brunt was borne maximally by those between 15 and 40 years. Females were more affected than males. It may be concluded from the study that 30% had no complications while 70% cases developed complications, 4% cases had underlying comorbidities and coinfections, 68% developed thrombocytopenia and other haemorrhagic features, 55% serositis, 25% acalculous cholecystitis, 20% myocarditis, 15% pancreatitis, 5% had central nervous system involvement, 0.66% rhabdomyolysis and myositis, 0.33% secondary vasculitis and death occurred in 3% cases. More number of patients were having multiple and atypical complications requiring hospitalisation. Mortality was more common in patients with associated comorbidities and coinfection. Awareness, early treatment with aggressive fluid replacement therapy with close monitoring, supportive management andpatient education showed promising results.

Characterization of a variant virus from ascitic fluid of subacute granulomatous serositis in interferon-gamma-deficient C57BL/6 mice persistently infected with murine coronavirus strain JHM.

Previously, we showed that intraperitoneal infection with murine coronavirus strain JHM (JHMV) established a persistent infection with subacute granulomatous serositis in interferon-gamma-deficient C57BL/6 (B6-GKO) mice. Herein, we characterize a variant virus from B6-GKO mice persistently infected with JHMV. Viruses were isolated from ascites at 25 d post-infection and cloned by limiting dilution on DBT cells; one variant was named 25V16G. To compare pathogenicity in vivo, we inoculated 25V16G and JHMV intraperitoneally into 8- to 12-week-old B6-GKO mice. Whereas nearly all of the B6-GKO mice infected with JHMV survived over 14 d, all of those infected with 25V16G died by 9 d post-infection. Histopathological examination revealed that 25V16G induced acute fulminant hepatitis in B6-GKO mice, whereas JHMV caused severe but focal hepatitis. The virus titer of 25V16G in the liver was 50- and 250-fold higher than that of JHMV at 5 and 7 d post-infection, respectively. However, there was no significant difference in viral growth between 25V16G and JHMV in cell lines cultured in vitro. Nucleotide sequencing of the S gene of 25V16G and JHMV revealed a deletion of 29 amino acids encompassing S(511-539), which covers a major cytotoxic T lymphocyte (CTL) epitope in C57BL/6 mice, and two point mutations resulting in amino acid changes in the S protein of 25V16G. One explanation for the greater pathogenicity of 25V16G is that 25V16G escapes CTL-mediated protection in B6-GKO mice. This experimental model may be used to assess the role of IFN-gamma in viral persistence in vivo.