H5N1 influenza A virus and infected human plasma.

摘要: To the Editor: Since January 2004, a total of 22 persons have been confirmed infected with avian influenza A virus (H5N1) in Thailand; 14 these patients died. Three waves outbreaks occurred during past 2 years. The last patient third wave was 5-year-old boy whose symptoms developed on November 28, 2005; he hospitalized December 5 and died days later. child resided Ongkharak District, Nakhon Nayok Province, ≈70 km northeast Bangkok. Villagers informed Department Livestock after patient's illness diagnosed. Five dead chickens had reported this area from 28 to 1, 2005. Samples could not be obtained, thus, no H5N1 testing performed. fever, headache, productive cough for 7 before admitted Her Royal Highness Princess Maha Chakri Sirindhorn Medical Center. Clinical examination chest radiograph showed evidence lobar pneumonia. He treated antimicrobial drugs (midecamycin penicillin G) supportive care, including oxygen therapy. On 7, condition worsened, severe pneumonia adult respiratory distress syndrome developed. Laboratory tests leukopenia (2,300 cells/mm3), acidosis, low blood saturation by cutaneous pulse oximetry (81.6%). Oseltamivir administered his parents hospital staff about boy's contact chicken. However, same day; autopsy 9, cause death declared Ministry Public Health virus. A sample collected 7; anticoagulation accomplished ethylenediaminetetraacetic acid (EDTA) repeated biochemistry analysis complete count. plasma EDTA separated later stored at –20°C 12 days. subsequently given Center Excellence Viral Hepatitis, Faculty Medicine, Chulalongkorn University, molecular diagnosis then –70°C, where specific precautions implemented handling highly infectious disease specimens such as were observed. Plasma examined multiplex reverse transcription–polymerase chain reaction (RT-PCR) (1) real-time RT-PCR (2), both which positive results virus. titer obtained 3.08 × 103 copies/mL. specimen processed isolation embryonated egg injection, according standard protocol described Harmon (3). Briefly, 100 μL 1:2 diluted injected into allantoic cavity 9-day-old incubated 37°C. embryo within 48 hours, fluid shown contain 2,048 hemagglutinin (HA) units; also, subtype (1,2). Whole genome sequencing performed submitted GenBank database under strain A/Thailand/NK165/05 accession no. DQ 372591-8. phylogenetic trees HA neuraminidase (NA) genes constructed using MEGA 3 (4) comparison viruses isolated humans, tigers, previous 2004 2005 (Figure). sequence analyses that cleavage site contained SPQREKRRKKR, differed an arginine-to-lysine substitution position 341. That finding also observed wild bird species earlier Thailand (5). Similar 2004–2005 isolates Thailand, 20–amino deletion NA stalk region Moreover, amino residues (E119, H274, R292, N294) active conserved, suggests sensitive oseltamivir. In addition, single glutamic lysine 627 PB2 increased replication efficiency mammals (6). Figure Phylogenetic study compared sequences (2004–2005). Observing live human serum or is unusual. 1963, quantities day 4 (7), 1970, cultivated (8). Recently, fatal case Vietnamese reported. determined isolating cerebrospinal fluid, fecal, throat, (9); viral RNA found 6 4–9 onset (10). case, 10 This blood, raises concern transmission among humans. Because probable humans has (11), should reminder necessity carefully handle transport samples suspected influenza. viable detected samples, handling, transportation, biosafety (category III) containment laboratory prevent spread healthcare workers. We express our thanks Research Fund (Senior Scholar), Golden Jubilee PhD Program Hepatitis Research, Prasert Auewarakul their generous support study.