Sequence Variation in Hepatitis E Virus Genotypes 3 and 4 from Swine Fecal Samples in Japan

Hepatitis E virus (HEV) is a causative agent for hepatitis. HEV is transmitted via the fecal-oral route through contaminated drinking water and induces zoonotic infections through eating uncooked and undercooked meat of deer, wild boar, and swine. In Japan, genotypes 3 (G3) and 4 (G4) are prevalent in domestic swine. Here, we examined the genetic variation among HEVs derived from swine fecal samples in Japan. A total of 320 samples were collected at 32 commercial farm facilities (1 fecal sample from each of 10 pig houses in individual farms). Viral RNA amplification at open reading frame (ORF) 3 was possible in 159 (49.7%) of the fecal samples. For genotyping, the same samples were subjected to amplification at ORF2 and the resulting amplicons were sequenced. The results revealed that all the HEVs in each farm belonged to the same cluster of G3 and G4: G3JP in 8 farms, G3SP in 4 farms, G3US in 6 farms, and G4JP in 2 farms, unclassified G3 in 2 farms, unable to decide due to a low rate of amplification in 5 farms, and no detection in 5 farms. Interestingly, the HEVs from one farm were more homogeneous than those of the same cluster that was derived from other farms. Thus, the efficiency of farm-to-farm transmission of HEVs is likely to be low and HEV seems to have evolved independently at each farm in Japan

Infectious prion protein in the filtrate even after 15 nm filtration.

The evaluation of the removal efficacy during manufacturing is important for the risk assessment of plasma products with respect to possible contamination by infectious prions, as recently reported in several papers on the potential for prion transmission through plasma products. Here, we evaluated a virus removal filter which has 15 nm pores. An antithrombin sample immediately prior to nano-filtration was spiked with prion material prepared in two different ways. The removal (log reduction factor) of prion infectivity using animal bioassays was >or=4.72 and 4.00 in two independent filtrations. However, infectivity was detected in both the pellet and supernatant following ultracentrifugation of the 15 nm filtered samples, indicating difficulty in complete removal. The data supports the conclusion that a certain amount of infectious prion protein is present as a smaller and/or soluble form (less than approximately 15 nm in diameter)

Neutralizing activities against seasonal influenza viruses in human intravenous immunoglobulin

Influenza viruses A/H1N1, A/H3N2, and B are known seasonal viruses that undergo annual mutation. Intravenous immunoglobulin (IVIG) contains anti-seasonal influenza virus globulins. Although the virus-neutralizing (VN) titer is an indicator of protective antibodies, changes in this titer over extended time periods have yet to be examined. In this study, variations in hemagglutination inhibition (HI) and VN titers against seasonal influenza viruses in IVIG lots over extended time periods were examined. In addition, the importance of monitoring the reactivity of IVIG against seasonal influenza viruses with varying antigenicity was evaluated. A/H1N1, A/H3N2, and B influenza virus strains and IVIG lots manufactured from 1999 to 2014 were examined. The HI titer was measured by standard methods. The VN titer was measured using a micro-focus method. IVIG exhibited significant HI and VN titers against all investigated strains. Our results suggest that the donor population maintains both specific and cross-reactive antibodies against seasonal influenza viruses, except in cases of pandemic viruses, despite major antigen changes. The titers against seasonal influenza vaccine strains, including past strains, were stable over short time periods but increased slowly over time