Monday, 29 July 2013

Influenza A(H7N9) virus review of 1st Hangzhou, Zhejiang Province death

Chen and colleagues provide a detailed description of the 1st death in this region (paper accepted in May). I believe this 39-year old male (39M) case was also briefly described in an earlier Lancet article.

Some key facts:
  • The patient had a chronic hepatitis B virus infection
  • Had contact with poultry (he was a cook) prior to presenting with cough and diarrhoea
  • Clinical features also included fever, shortness of breath, weakness, poor appetite, cyanosis and coma
  • Laboratory biochemical and haematological features included raised enzymes (AST, ALT, LDH, CPK), bleeding/clotting times (PT, APTT) and C-reactive protein (CRP)
  • Oxygen saturatiuon decreased with disease progression
  • Was treated with antibiotics but not antivirals
  • Virus was detected using real-time reverse-transcription PCR (RT-rtPCR)
  • Subgenomic (less than full genome; A/Zhejiang/1/2013) sequences were examined for HA (closest relative, A/duck/Thailand), NA (closest relative A/wild bird/Korea) and M (closest relative A/chicken/El-Fayoun) genes and each shared >99.1% nucleotide identity with Anhui/1 and Shanghai/1 and Shanghai/2 strains
  • A pharyngeal swab sample yieled a virus isolate, A/Zhejiang/1/2013, on MDCK cells grown at 37°C, observed fro 14-days, and identified using PCR and a haemagglutination assay after the appearance of cell damage
  • Contacts were all negative by RT-rtPCR