Factors associated with influenza vaccination failure and severe disease in a French region in 2015

Built-in RNA-mediated chaperone (chaperna) for antigen folding tailored to immunized hosts

High‐quality antibody (Ab) production depends on the availability of immunologically relevant antigens. We present a potentially universal platform for generating soluble antigens from bacterial hosts, tailored to immunized animals for Ab production. A novel RNA‐dependent chaperone, in which the target antigen is genetically fused with an RNA‐interacting domain (RID) docking tag derived from the immunized host, promotes the solubility and robust folding of the target antigen. We selected the N‐terminal tRNA‐binding domain of lysyl‐tRNA synthetase (LysRS) as the RID for fusion with viral proteins and demonstrated the expression of the RID fusion proteins in their soluble and native conformations; immunization predominantly elicited Ab responses to the target antigen, whereas the “self” RID tag remained nonimmunogenic. Differential immunogenicity of the fusion proteins greatly enriched and simplified the screening of hybridoma clones of monoclonal antibodies (mAbs), enabling specific and sensitive serodiagnosis of MERS‐CoV infection. Moreover, mAbs against the consensus influenza hemagglutinin stalk domain enabled a novel assay for trivalent seasonal influenza vaccines. The Fc‐mediated effector function was demonstrated, which could be harnessed for the design of next‐generation “universal” influenza vaccines. The nonimmunogenic built‐in antigen folding module tailored to a repertoire of immunized animal hosts will drive immunochemical diagnostics, therapeutics, and designer vaccines.

Effect of seasonal influenza vaccination on influenza symptom severity among children in Hutterite communities: Follow-up study of a randomized trial

BACKGROUND

We investigated whether influenza vaccination reduces symptom severity among children who develop laboratory-confirmed influenza, and whether this association differed between influenza vaccine formulations.

METHODS

We performed a retrospective cohort study using data from two blinded cluster randomized control trials of influenza vaccines in Hutterite colonies. In trial 1, children received trivalent inactivated influenza vaccine (TIV) or hepatitis A vaccine. In trial 2, children received trivalent live attenuated (TLAIV) or TIV. We assessed four outcomes (total number of symptoms, number of respiratory symptoms, number of systemic symptoms, and duration of symptoms) among children with PCR-confirmed influenza. We utilized two-sample t tests to quantify the relationship between vaccine group and outcome. We performed multivariable strain-specific analyses, controlling for age and season.

RESULTS

TIV vs. Hep A vaccine: Among vaccinated children, 200 confirmed influenza infections were observed across 3014 person-seasons. Vaccine type (TIV vs. Hep A vaccine) did not significantly affect the number of respiratory or systemic symptoms, nor duration of symptoms (P > .05). TLAIV vs. TIV: Among 1186 children who received a study vaccine, 166 confirmed influenza infections were observed. TLAIV recipients experienced fewer total, respiratory, and systemic symptoms compared to TIV recipients (P < .05 for all). TLAIV-associated attenuation of symptom severity was observed in influenza B or A/H1N1 infections, but not H3.

CONCLUSIONS

Seasonal influenza vaccine did not consistently attenuate symptom severity in the context of vaccine failure; however, TLAIV offered superior severity attenuation compared to TIV. Our results challenge the dictum that influenza vaccine reduces the severity of symptoms even when the vaccine fails to prevent influenza.

Co-infection with avian hepatitis E virus and avian leukosis virus subgroup J as the cause of an outbreak of hepatitis and liver hemorrhagic syndromes in a brown layer chicken flock in China

Hens of a commercial Hy-line brown layer flock in China exhibited increased mortality and decreased egg production at 47 wk of age. From 47 to 57 wk, average weekly mortality increased from 0.11 to 3.0%, and egg production decreased from 10 to 30%, with a peak mortality rate (3.0%) observed at 54 wk of age. Necropsy of 11 birds demonstrated tissue damage that included hepatitis, liver hemorrhage, rupture, and/or enlarged livers. Microscopic liver lesions exhibited hepatocytic necrosis, lymphocytic periphlebitis, and myeloid leukosis. While no bacteria were recovered from liver and spleen samples, avian hepatitis E virus (HEV) RNA was detected in all 11 tested hens by nested reverse transcription-polymerase chain reaction. Of these, subgroup J avian leukosis virus (ALV-J) proviral DNA was detected in 5 hens by PCR. Alignments of partial ORF2 gene sequences obtained here demonstrated shared identity (76 to 97%) with corresponding sequences of other known avian HEV isolates. Env sequences of ALV-J isolates obtained here shared 50.1 to 55% identity with other ALV subgroups and 91.8 to 95.5% identity with other known ALV-J isolates. Phylogenetic tree analysis of selected sequences obtained here grouped an avian HEV sequence with genotype 3 HEV and assigned an ALV-J sequence to a branch separate from known ALV-J subgroups. Immunohistochemical results confirmed the presence of avian HEV and ALV-J in livers. Therefore, these results suggest that avian HEV and ALV-J co-infection caused the outbreak of hepatitis and liver hemorrhagic syndrome observed in the layer hen flock analyzed in this study.