The number of anatomical sites with detectable viral loads by RT-qPCR appeared to correlate with death risk.

No abstract

Using paired serum samples obtained from patients with illness associated with increases in anti-human coronavirus OC43 (HCoV-OC43) or anti-HCoV-229E antibodies, we examined the possibility of false-positive results detected in a recombinant severe acute respiratory syndrome (SARS)-associated coronavirus (SARSCoV) nucleocapsid protein immunoglobulin G enzyme-linked immunosorbent assay (ELISA). Three of the 21 and 1 of the 7 convalescent-phase serum samples from persons with increases in antibodies against HCoV-OC43 and HCoV-229E, respectively, tested positive by the recombinant SARS-CoV nucleocapsid protein-based ELISA. None of these samples were found to contain a specific antibody in the recombinant SARS-CoV spike polypeptide-based Western blot assay.Severe acute respiratory syndrome (SARS), caused by SARS-associated coronavirus (SARS-CoV), has affected 30 countries in five continents, with more than 8,000 cases and 750 deaths (7-11). As for the detection of antibodies against SARS-CoV, at the moment, the most widely used methods are antibody detection in acute-and convalescent-phase sera by indirect immunofluorescence assay and enzyme-linked immunosorbent assay (ELISA) using cell culture extracts (4,8,10). However, antibody detection by these methods may be less reproducible, more difficult to standardize, and more laborintensive than ELISA-based antibody detection tests using recombinant antigens. Furthermore, producing the infected cell lines for coating the ELISA plates and the slides for indirect immunofluorescence requires cultivation of the SARS-CoV, for which biosafety level 3 laboratory facilities are required. Such facilities are not available in most clinical microbiology laboratories.ELISA-based antibody detection tests using recombinant antigens are well known to offer higher reproducibility and to be easier to standardize and less labor-intensive than antibody detection by indirect immunofluorescence assay and ELISA using cell culture extract, and they do not require cultivation of the SARS-CoV (1, 2, 14, 18). Recently, we have reported the use of recombinant SARS-CoV nucleocapsid protein ELISAbased antibody tests for serodiagnosis of SARS-CoV pneumonia and the study of the seroprevalence of nonpneumonic SARS-CoV infections (15, 16). In addition, others have also reported the use of recombinant-protein-based immunoassays for serodiagnosis of SARS-CoV pneumonia (3, 17). However, in our studies, we have also shown that false-positive reactions were detected if the recombinant SARS-CoV nucleocapsid protein-based ELISA was used alone for antibody detection (15). In this study, using paired serum samples obtained from patients with increases in anti-human CoV OC43 (HCoV-OC43) or anti-HCoV-229E antibodies, we examined the possibility of false-positive results detected by the recombinant SARS-CoV nucleocapsid protein-based ELISA. The importance of using Western blot assays, with the nucleocapsid protein and spike polypeptide of SARS-CoV, for confirmation was also determined.Paired serum samples collecte...

We compared the clinical and laboratory features of human immunodeficiency virus (HIV)- and non-HIV-infected patients with penicilliosis marneffei. HIV-infected patients had a higher incidence of fungemia. A total of 85.7% of the HIV-negative patients had underlying diseases including hematologic malignancies or had received therapy with corticosteroids or cytotoxic agents. By a Penicillium marneffei -specific mannoprotein Mp1p enzyme-linked immunosorbent assay, serum antigen titers were found to be higher in HIV-positive patients, whereas serum antibody levels were found to be higher in HIV-negative patients.

In a territory-wide surveillance study, Laribacter hongkongensis was isolated solely from freshwater fish (60% of grass carps, 53% of bighead carps, and 25% of mud carps). Comparing the pulsed-field gel electrophoresis patterns of fish and patient isolates revealed that most patient isolates were clustered together, suggesting that some clones could be more virulent.Laribacter hongkongensis was first discovered in Hong Kong from the blood and empyema pus of a 54-year-old Chinese man with alcoholic cirrhosis (5). Subsequently, L. hongkongensis was discovered in three of our patients and three patients in Switzerland with community-acquired gastroenteritis (3). In a multicenter prospective study, we confirmed that L. hongkongensis is associated with community-acquired gastroenteritis and traveler's diarrhea (4). Freshwater fish were shown to be a reservoir of L. hongkongensis (4). The isolation of L. hongkongensis from patients who resided in or have recently traveled to Asia, Europe, America, and Africa implied that the bacterium is likely to be of global importance.In this study, in order to determine the prevalence of L. hongkongensis in different animals commonly used for cooking in our locality, we carried out an ecoepidemiology study in Hong Kong. Furthermore, to determine the genetic diversity of L. hongkongensis, all L. hongkongensis isolates were typed by pulsed-field gel electrophoresis (PFGE). The PFGE patterns were compared to those of L. hongkongensis strains isolated from patients with gastroenteritis.Fecal swabs were obtained from 350 pigs and 80 cows, and cloacal swabs were obtained from 400 chickens, 50 ducks, and 50 geese from slaughter houses and poultry farms in Hong Kong with assistance from Veterinary Public Health Section of the Food and Environmental Hygiene Department. Three hundred and sixty freshwater fish (mostly farmed) of six different species and 360 marine fish of six different species commonly purchased for cooking in Hong Kong were obtained from 10 retail food markets (six fish per species per market) located in different districts of Hong Kong. Samples were obtained from the midguts and hindguts of the fish by using sterile cotton wool swabs. All samples were plated onto cefoperazone MacConkey agar and incubated under aerobic conditions at 37°C for 48 h (1). All suspected isolates were identified phenotypically by standard conventional biochemical methods (2). Isolates suspected to be L. hongkongensis were subjected to 16S rRNA gene sequencing (3, 4). All L. hongkongensis isolates were subjected to PFGE (3, 4). Digital images were stored electronically as TIFF files and analyzed visually and with GelCompar II (version 3.0; Applied Maths, Kortrijk, Belgium) by using the Dice coefficient and represented by the unweighted pair-group method using average linkages with 1% tolerance and 0.5% optimization settings.L. hongkongensis was isolated from the midguts and hindguts of 86 (24%) of 360 freshwater fish, including 36 (60%) grass carps, 32 (53%) bighead carps, 15 (25%) mud carps, and...

No abstract

A highly reproducible and discriminative typing system is essential for better understanding of the epidemiology of Penicillium marneffei, the most important thermal dimorphic fungus causing respiratory, skin, and systemic mycosis in Southeast Asia. The sequences of 11 housekeeping genes were identical among 10 strains of P. marneffei, but those of MP1 and its 13 homologues, a novel superfamily of mannoproteins in the subdivision Pezizomycotina of Ascomycetes, mostly species of Penicillium and Aspergillus, showed significant variations. Therefore, a multilocus sequence typing (MLST) system for P. marneffei was constructed using MP1

No abstract