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Squirrelpox virus (SQPV) shows little evidence for morbidity or mortality in North American grey squirrels (Sciurus carolinensis), in which the virus is endemic. However, more recently the virus has emerged to cause epidemics with high mortality in Eurasian red squirrels (S. vulgaris) in Great Britain, which are now threatened. Here we report the genome sequence of SQPV. Comparison with other Poxviridae revealed a core set of poxvirus genes, the phylogeny of which showed SQPV to be in a new Chordopoxvirus subfamily between the Molluscipoxviruses and Parapoxviruses. A number of SQPV genes were related to virulence, including three major histocomaptibility class I homologs, and one CD47 homolog. In addition, a novel potential virulence factor showing homology to mammalian oligoadenylate synthetase (OAS) was identified. This family of proteins normally causes activation of an endoribonuclease (RNaseL) within infected cells. The putative function of this novel SQPV protein was predicted in silico. [ABSTRACT FROM AUTHOR]

Background: An increase in non-B HIV-1 infections among men who have sex with men (MSM) in the United Kingdom (UK) has created opportunities for novel recombinants to arise and become established. We used molecular mapping to characterize the importance of such recombinants to the UK HIV epidemic, in order to gain insights into transmission dynamics that can inform control strategies. Methods and Results: A total of 55,556 pol (reverse transcriptase and protease) sequences in the UK HIV Drug Resistance Database were analyzed using Subtype Classification Using Evolutionary Algorithms (SCUEAL). Overall 72 patients shared the same A1/D recombination breakpoint in pol, comprising predominantly MSM but also heterosexuals and injecting drug users (IDUs). In six MSM, full-length single genome amplification of plasma HIV-1 RNA was performed in order to characterize the A1/D recombinant. Subtypes and recombination breakpoints were identified using sliding window and jumping profile hidden markov model approaches. Global maximum likelihood trees of gag, pol and env genes were drawn using FastTree version 2.1. Five of the six strains showed the same novel A1/D recombinant (8 breakpoints), which has been classified as CRF50_A1D. The sixth strain showed a complex CRF50_A1D/B/U structure. Divergence dates and phylogeographic inferences were determined using Bayesian Evolutionary Analysis using Sampling Trees (BEAST). This estimated that CRF50_A1D emerged in the UK around 1992 in MSM, with subsequent transmissions to heterosexuals and IDUs. Analysis of CRF50_A1D/B/U demonstrated that around the year 2000 CRF50_A1D underwent recombination with a subtype B strain. Conclusions: We report the identification of CRF50_A1D, a novel circulating recombinant that emerged in UK MSM around 1992, with subsequent onward transmission to heterosexuals and IDUs, and more recent recombination with subtype B. These findings highlight the changing dynamics of HIV transmission in the UK and the converging of the two previously distinct MSM and heterosexual epidemics. [ABSTRACT FROM AUTHOR]

Noroviruses are a common cause of gastroenteritis worldwide, but outbreaks appear to be more common in industrialized countries than in developing countries, possibly reflecting differences in exposure and immunity. In this study, age-stratified sera from India and UK populations were analysed for the presence of norovirus-genogroup II specific IgG by a time resolved immunofluorescence assay and relative levels of antibodies in the two populations were compared. Antibody levels were higher among all age groups in India than in UK and increased with age in India, whereas in the UK, levels of antibody decreased in adulthood. These results indicate different patterns of exposure to noroviruses in the two countries. [ABSTRACT FROM AUTHOR]