Kwok H Chan

The University of Hong Kong, Hong Kong, Hong Kong

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Publications (19)190.35 Total impact

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    ABSTRACT: Sequence-independent amplification of clinical specimens can lead to the identification of novel pathogens. To identify novel viruses in human stool specimens from patients with diarrhea and to investigate the ecology and clinical significance of such viruses. Nucleic acid extracted from stool specimens from patients with diarrhea with no known etiology were subjected to random PCR amplification and Roche/454 pyrosequencing. Novel viruses identified were genetically and epidemiologically characterized. Four gyroviruses, chicken anemia virus (CAV), human gyrovirus (HGV)/avian gyrovirus 2 (AGV2), gyrovirus 3 (GyV3) and a novel gyrovirus (tentatively designated as gyrovirus 4 (GyV4)) were identified in human stool specimens. GyV4, as well as CAV and AGV2/HGV were also detected in chicken skin and meat used for human consumption. A novel gyrovirus (GyV4) was identified in human stool and in chicken meat sold for human consumption. This virus was phylogenetically distinct from previously reported gyroviruses in chicken and humans (chicken anemia virus, human gyrovirus, avian gyrovirus 2 and recently reported gyrovirus 3). The epidemiology and pathogenesis of this virus in humans and in chicken needs to be further investigated.
    Journal of clinical virology: the official publication of the Pan American Society for Clinical Virology 07/2012; 55(3):209-13. DOI:10.1016/j.jcv.2012.07.001 · 3.47 Impact Factor
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    ABSTRACT: Please cite this paper as: Wong et al. (2012) Cigarette smoking as a risk factor for influenza-associated mortality: evidence from an elderly cohort. Influenza and Other Respiratory Viruses DOI:10.1111/j.1750-2659.2012.00411.x. Background  The effects of individual lifestyle factors on the mortality risk after influenza infection have not been explored. Objectives  In this study, we assessed the modifying effects of cigarette smoking on mortality risks associated with influenza in a cohort of Hong Kong elders with a follow-up period of 1998-2009. Methods  We used the Cox proportional hazards model with time-dependent covariates of weekly proportions of specimens positive for influenza (termed as influenza virus activity), to calculate the hazard ratio of mortality associated with a 10% increase in influenza virus activity for never, ex- and current smokers. Other individual lifestyle and socioeconomic factors as well as seasonal confounders were also added into the models. Results  The overall hazard ratio associated with influenza was 1·028 (95% confidence interval, 1·006, 1·051) for all natural cause mortality and 1·035 (1·003, 1·068) for cardiovascular and respiratory mortality. We found that influenza-associated hazard ratio was greater in current and ex-smokers than in never smokers for mortality of all natural causes, cardiovascular and respiratory diseases. Conclusions  The findings suggest that smoking might increase influenza-associated mortality risks among elders.
    Influenza and Other Respiratory Viruses 07/2012; 7(4). DOI:10.1111/j.1750-2659.2012.00411.x · 1.90 Impact Factor
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    ABSTRACT: Nasopharyngeal carcinoma (NPC) is endemic in China and Southeast Asia where it is tightly associated with infections by Epstein-Barr virus (EBV). The role of tumor-associated viral antigens in NPC renders it an appealing candidate for cellular immunotherapy. In earlier preclinical studies, a novel adenoviral vector-based vaccine termed AdE1-LMPpoly has been generated that encodes EBV nuclear antigen-1 (EBNA1) fused to multiple CD8(+) T-cell epitopes from the EBV latent membrane proteins, LMP1 and LMP2. Here, we report the findings of a formal clinical assessment of AdE1-LMPpoly as an immunotherapeutic tool for EBV-associated recurrent and metastatic NPC. From a total of 24 patients with NPC, EBV-specific T cells were successfully expanded from 16 patients with NPC (72.7%), whereas six patients with NPC (27.3%) showed minimal or no expansion of virus-specific T cells. Transient increase in the frequencies of LMP1&2- and EBNA1-specific T-cell responses was observed after adoptive transfer to be associated with grade I flu-like symptoms and malaise. The time to progression in these patients ranged from 38 to 420 days with a mean time to progression of 136 days. Compared with patients who did not receive T cells, the median overall survival increased from 220 to 523 days. Taken together, our findings show that adoptive immunotherapy with AdE1-LMPpoly vaccine is safe and well tolerated and may offer clinical benefit to patients with NPC.
    Cancer Research 03/2012; 72(5):1116-25. DOI:10.1158/0008-5472.CAN-11-3399 · 9.28 Impact Factor
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    ABSTRACT: Populations of seasonal influenza virus experience strong annual bottlenecks that pose a considerable extinction risk. It has been suggested that an influenza source population located in tropical Southeast or East Asia seeds annual temperate epidemics. Here we investigate the seasonal dynamics and migration patterns of influenza A H3N2 virus by analysis of virus samples obtained from 2003 to 2006 from Australia, Europe, Japan, New York, New Zealand, Southeast Asia, and newly sequenced viruses from Hong Kong. In contrast to annual temperate epidemics, relatively low levels of relative genetic diversity and no seasonal fluctuations characterized virus populations in tropical Southeast Asia and Hong Kong. Bayesian phylogeographic analysis using discrete temporal and spatial characters reveal high rates of viral migration between urban centers tested. Although the virus population that migrated between Southeast Asia and Hong Kong persisted through time, this was dependent on virus input from temperate regions and these tropical regions did not maintain a source for annual H3N2 influenza epidemics. We further show that multiple lineages may seed annual influenza epidemics, and that each region may function as a potential source population. We therefore propose that the global persistence of H3N2 influenza A virus is the result of a migrating metapopulation in which multiple different localities may seed seasonal epidemics in temperate regions in a given year. Such complex global migration dynamics may confound control efforts and contribute to the emergence and spread of antigenic variants and drug-resistant viruses.
    Proceedings of the National Academy of Sciences 11/2011; 108(48):19359-64. DOI:10.1073/pnas.1109314108 · 9.81 Impact Factor
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    Raymond J Ning · Xue Q Xu · Kwok H Chan · Alan K S Chiang
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    ABSTRACT: T cells simultaneously producing multiple cytokines and possessing cytotoxic capacity termed polyfunctional cells (PFCs) are increasingly recognized as the immune correlate of protection against pathogenic viruses. We investigated co-expression of four cytokines (interferon-γ, macrophage inflammatory protein 1-α, tumour necrosis factor-α and interleukin-2) and degranulation capacity (CD107a surface expression) of Epstein-Barr virus (EBV) -specific CD4(+) and CD8(+) T cells upon stimulation by overlapping peptides of EBV lytic (BZLF1) and latent (EBNA1, EBNA3 and LMP2) proteins, in 20 healthy Chinese long-term carriers. Two patients with post-transplant lymphoproliferative disorder (PTLD), who had impaired T-cell immunity, were studied for comparison. Both EBV-specific CD4(+) and CD8(+) PFCs were readily generated in long-term carriers and showed immunodominance hierarchies of latent proteins (EBNA1 > EBNA3/LMP2 and EBNA3 > LMP2 > EBNA1 for CD4(+) and CD8(+) T cells, respectively), as evidenced by a higher proportion of PFCs generated by immunodominant EBV proteins than by subdominant viral proteins. In contrast, the proportion of EBV-specific PFCs was markedly decreased in patients with PTLD. The EBV-specific PFCs produced more cytokine per cell than single-functional T cells and comprised different subsets. Five-functional CD4(+) and CD8(+) T cells were detected and four-functional CD4(+) T cells were mainly CD107a negative and expressed all four cytokines whereas four-functional CD8(+) T cells were mainly CD107a positive and expressed three of the four cytokines (interleukin-2-negative). We conclude that EBV-specific PFCs are generated in much higher proportions in the long-term carriers than in the patients with PTLD and maintain the immunodominant characteristics of the virus.
    Immunology 10/2011; 134(2):161-71. DOI:10.1111/j.1365-2567.2011.03476.x · 3.74 Impact Factor
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    ABSTRACT: The recent emergence of a novel H1N1 influenza A virus in humans caused the first influenza pandemic of this century. Many clinical diagnostic laboratories are overwhelmed by the testing demands related to the infection. Three novel H1N1-specific primer-probe sets reported during the early phase of the pandemic were tested in three commercial real-time RT-PCR mixtures. The amplification efficiencies and detection limits of these assays were determined. A ready-to-use premixed RT-PCR stored in a lyophilized format was developed. The detection limits of the studied assays were highly variable, ranging from 1.68E-01 to 1.68E-05 TCID(50) per reaction. The detection limit of the lyophilized reaction mixture was found to be 1.68E-05 TCID(50) per reaction, but the amplification efficiency of the assay was lower than those deduced from the other assays. All respiratory samples from infected patients and all control nasopharyngeal aspirates were positive and negative, respectively, in the newly developed assay. The results highlighted that, to enhance the sensitivity of an assay, it is essential to evaluate a primer-probe set with different commercial RT-PCR assays. This study also demonstrated the feasibility of using lyophilized reaction mixtures for the molecular diagnosis of novel H1N1.
    Journal of virological methods 02/2010; 165(2):302-4. DOI:10.1016/j.jviromet.2010.01.024 · 1.88 Impact Factor
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    ABSTRACT: It is increasingly clear that influenza A infection induces cross-subtype neutralizing antibodies that may potentially confer protection against zoonotic infections. It is unclear whether this is mediated by antibodies to the neuraminidase (NA) or haemagglutinin (HA). We use pseudoviral particles (H5pp) coated with H5 haemagglutinin but not N1 neuraminidase to address this question. In this study, we investigate whether cross-neutralizing antibodies in persons unexposed to H5N1 is reactive to the H5 haemagglutinin. We measured H5-neutralization antibody titers pre- and post-vaccination using the H5N1 micro-neutralization test (MN) and H5pp tests in subjects given seasonal vaccines and in selected sera from European elderly volunteers in a H5N1 vaccine trial who had detectable pre-vaccination H5N1 MN antibody titers. We found detectable (titer > or = 20) H5N1 neutralizing antibodies in a minority of pre-seasonal vaccine sera and evidence of a serological response to H5N1 in others after seasonal influenza vaccination. There was excellent correlation in the antibody titers between the H5N1 MN and H5pp tests. Similar correlations were found between MN and H5pp in the pre-vaccine sera from the cohort of H5N1 vaccine trial recipients. Heterosubtype neutralizing antibody to H5N1 in healthy volunteers unexposed to H5N1 is mediated by cross-reaction to the H5 haemagglutinin.
    PLoS ONE 11/2009; 4(11):e7918. DOI:10.1371/journal.pone.0007918 · 3.23 Impact Factor
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    ABSTRACT: We conducted this study to test the hypothesis that intradermal influenza vaccination at one fifth of a standard dose elicits comparable immunogenicity to full-dose intramuscular vaccination in children. We conducted a randomized, open-label study in 112 healthy children aged 3 to <18 years to compare the immunogenicity and safety of intradermal vaccination at one fifth of a dose with standard intramuscular vaccination. Analyses of hemagglutination inhibition antibody titers to each antigen in each group included geometric mean titers before and 21 days after vaccination, fold increase in geometric mean titers after vaccination, seroprotection rate, and seroconversion rate. The mean age of the subjects was 10.11 +/- 4.04 years in the intradermal vaccination group and 10.57 +/- 3.91 years in the intramuscular group. Intradermal vaccination was safe. Induration and mild erythema at the injection site were reported at 25% and 57%, respectively, in the intradermal group. Fold increase of geometric mean titers against influenza A/Caledonia was robust in both groups (11.1-fold and 12.9-fold increase in the intramuscular and intradermal groups, respectively), whereas that for B/Shandong was more modest (4.3-4.4). Both approaches elicited very high geometric mean titers against influenza A/Panama: 1360.5 and 893.9 for the intramuscular and intradermal groups, respectively, but because the prevaccination antibody titers were high, the fold increase of geometric mean titers was only 4.5 and 2.6, respectively. The immunogenicity of one fifth of a dose of influenza vaccine delivered by the intradermal route is comparable to the standard-dose intramuscular vaccination in children as young as 3 years of age.
    PEDIATRICS 07/2007; 119(6):1076-82. DOI:10.1542/peds.2006-3176 · 5.30 Impact Factor
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    ABSTRACT: We describe a 1-step reverse-transcription loop-mediated isothermal amplification assay for detection of highly pathogenic avian influenza A (H5N1) viruses. The assay was tested by using a panel of highly pathogenic H5N1 subtypes isolated over the past 10 years and clinical specimens. The assay produced negative results for all non-H5N1 subtypes.
    Emerging infectious diseases 07/2007; 13(6):899-901. DOI:10.3201/eid1306.061572 · 7.33 Impact Factor
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    ABSTRACT: The impact of influenza on morbidity and hospitalization in the tropics and subtropics is poorly quantified. Uniquely, the Hong Kong Special Administrative Region has computerized hospital discharge diagnoses on 95% of total bed days, allowing disease burden for a well-defined population to be accurately assessed. Influenza-associated morbidity and hospitalization was assessed by Poisson regression models for weekly counts of hospitalizations in Hong Kong during 1996 to 2000, using proportions of positive influenza types A (H1N1 and H3N2) and B isolations in specimens sent for laboratory diagnosis as measures of influenza virus circulation. We adjusted for annual trend, seasonality, temperature, and relative humidity, as well as respiratory syncytial virus circulation. We found that influenza was significantly associated with hospitalization for acute respiratory disease (International Classification of Diseases version 9 codes [ICD9] 460-466 and 480-487) and its subcategory pneumonia and influenza (ICD9 480-487) for all age groups. The annual rates of excess hospitalization per 100,000 population for acute respiratory diseases for the age groups 0-14, 15-39, 40-64, 65-74, and 75+ were 163.3 (95% confidence interval [CI], 135-190), 6.0 (95% CI, 2.7-8.9), 14.9 (95% CI, 10.7-18.8), 83.8 (95% CI, 61.2-104.2), and 266 (95% CI, 198.7-330.2), respectively. Influenza was also associated with hospitalization for cerebrovascular disease (ICD9 430-438) for those aged over 75 y (55.4; 95% CI, 23.1-87.8); ischemic heart disease (ICD9 410-414) for the age group 40-64 y (5.3; 95% CI, 0.5-9.5) and over 75 y (56.4; 95% CI, 21.1-93.4); and diabetes mellitus (ICD9 250) for all age groups older than 40 y. Influenza has a major impact on hospitalization due to cardio-respiratory diseases as well as on cerebrovascular disease, ischemic heart disease, and diabetes mellitus in the tropics and subtropics. Better utilization of influenza vaccine during annual epidemics in the tropics will enhance global vaccine production capacity and allow for better preparedness to meet the surge in demand that is inevitable in confronting a pandemic.
    PLoS Medicine 05/2006; 3(4):e121. DOI:10.1371/journal.pmed.0030121 · 14.00 Impact Factor
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    ABSTRACT: Malaria is one of the most important parasitic infections in humans. A sensitive diagnostic test for malaria that could be applied at the community level could be useful in programs to control the disease. The aim of the present work was to develop a simple, inexpensive molecular test for Plasmodium falciparum. Blood was collected from controls (n = 100) and from patients diagnosed with falciparum malaria infection (n = 102), who were recruited to the study. Heat-treated blood samples were tested by a loop-mediated isothermal amplification (LAMP) assay for P. falciparum. Results were interpreted by a turbidity meter in real time or visually at the end of the assay. To evaluate the assay, DNA from these samples was purified and tested by PCR. Results from the LAMP and PCR assays were compared. The LAMP assay detected P. falciparum directly from heat-treated blood. The quantitative data from the assay correlated to the parasite counts obtained by blood-film microscopic analyses. When we used the PCR assay as the comparison method, the sensitivity and specificity of the LAMP assay were 95% and 99%, respectively. Unlike PCR, the LAMP assay does not require purified DNA for efficient DNA amplification, thereby reducing the cost and turnaround time for P. falciparum diagnosis. The assay requires only basic instruments, and assay positivity can be verified by visual inspection.
    Clinical Chemistry 03/2006; 52(2):303-6. DOI:10.1373/clinchem.2005.057901 · 7.77 Impact Factor
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    ABSTRACT: We compared the performance of a recently established real-time loop-mediated amplification (LAMP) assay with the one from a highly sensitive quantitative PCR assay. None of these assays produced false-positive results in this study. For samples isolated from patients within the first 3 days of disease onset, the detection rate of the quantitative PCR assay was higher (14 of 15 were positive) than the LAMP assay (9 of 15 were positive). By contrast, the detection rates of these assays toward specimens sampled from patients with more than 3 days of illness were similar (32 of 44 for PCR and 33 of 44 for LAMP were positive). The simpler operation of LAMP might be a possible solution for on-site diagnosis.
    Journal of Clinical Microbiology 08/2005; 43(7):3457-9. DOI:10.1128/JCM.43.7.3457-3459.2005 · 4.23 Impact Factor
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    ABSTRACT: Four clinical isolates of SARS coronavirus were serially passaged in two primate cell lines (FRhK4 and Vero E6). Viral genetic sequences encoding for structural proteins and open reading frames 6--8 were determined in the original clinical specimen, the initial virus isolate (passage 0) and at passages 5, 10, and 15. After 15 passages, a total of 15 different mutations were identified and 12 of them were non-synonymous mutations. Seven of these mutations were recurrent mutation and all located at the spike, membrane, and Orf 8a protein encoding sequences. Mutations in the membrane protein and a deletion in ORF 6--8 were already observed in passage 0, suggesting these amino acid substitutions are important in the adaptation of the virus isolate in primate cell culture. A mutation in the spike gene (residue 24079) appeared to be unique to adaptation in FRhK4 cells. It is important to be aware of cell culture associated mutations when interpreting data on molecular evolution of SARS coronavirus.
    Journal of Medical Virology 08/2005; 76(4):435-40. DOI:10.1002/jmv.20379 · 2.22 Impact Factor
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    ABSTRACT: Here we describe the use of the loop-mediated isothermal amplification (LAMP) method to detect human influenza viruses (H1 to H3). Our results were correlated 100% with results deduced from routine clinical diagnostic tests. In addition, we also developed a LAMP assay specific for human beta-actin cDNA as a quality control test.
    Journal of Clinical Microbiology 02/2005; 43(1):427-30. DOI:10.1128/JCM.43.1.427-430.2005 · 4.23 Impact Factor
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    ABSTRACT: Cases of severe acute respiratory syndrome (SARS) were investigated for SARS coronavirus (SARS-CoV) through RNA tests, serologic response, and viral culture. Of 537 specimens from patients in whom SARS was clinically diagnosed, 332 (60%) had SARS-CoV RNA in one or more clinical specimens, compared with 1 (0.3%) of 332 samples from controls. Of 417 patients with clinical SARS from whom paired serum samples were available, 92% had an antibody response. Rates of viral RNA positivity increased progressively and peaked at day 11 after onset of illness. Although viral RNA remained detectable in respiratory secretions and stool and urine specimens for >30 days in some patients, virus could not be cultured after week 3 of illness. Nasopharyngeal aspirates, throat swabs, or sputum samples were the most useful clinical specimens in the first 5 days of illness, but later in the illness viral RNA could be detected more readily in stool specimens.
    Emerging infectious diseases 02/2004; 10(2):294-9. DOI:10.3201/eid1002.030610 · 7.33 Impact Factor
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    ABSTRACT: We assessed 5 EBV specific assays for their capacity to effect serologic diagnosis of suspected NPC. The assays were the immunofluorescent assays, VCA IgA and EA IgA, the enzyme-linked immunosorbent assays specific for EBNA 1 IgA or zta IgG and an EBV DNA assay. Serum samples were taken from 218 symptomatic NPC patients presenting consecutively at a public hospital in Hong Kong, 51 of whom were subsequently diagnosed as having NPC; 4 had EBV-associated lung cancer with similar serology as NPC. The remaining patients included 23 who had other cancers and 140 who had other diseases. Objectives of serodiagnosis under such clinical settings, therefore, are to both exclude and predict a diagnosis of NPC. None of the assays individually can meet both requirements adequately, however. The difficulty was best overcome by combining EBNA 1 IgA and zta IgG. It was shown that 68.3% of the patients gave a confirmed test results, negative or positive, by both tests. A confirmed negative result was associated with a negative predictive value of 99.1%, providing a clear indication to exclude a diagnosis of NPC; a confirmed positive result was associated with a positive predictive value of 86.8%, providing a clear indication to proceed with diagnostic work-up of NPC. The remaining patients gave equivocal test results, being positive for one or the other test, which were associated with a positive predictive value of 43.3% and 24.2%, respectively.
    International Journal of Cancer 07/2003; 105(5):706-9. DOI:10.1002/ijc.11130 · 5.01 Impact Factor
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    ABSTRACT: Severe acute respiratory syndrome (SARS) is a novel infectious disease with global impact. A virus from the family Coronaviridae has been identified as the cause, but the pathogenesis is still unclear. Post-mortem tissue samples from six patients who died from SARS in February and March, 2003, and an open lung biopsy from one of these patients were studied by histology and virology. Only one full autopsy was done. Evidence of infection with the SARS-associated coronavirus (SARS-CoV) and human metapneumovirus was sought by reverse-transcriptase PCR and serology. Pathological samples were examined by light and electron microscopy and immunohistochemistry. All six patients had serological evidence of recent infection with SARS-CoV. Diffuse alveolar damage was common but not universal. Morphological changes identified were bronchial epithelial denudation, loss of cilia, and squamous metaplasia. Secondary bacterial pneumonia was present in one case. A giant-cell infiltrate was seen in four patients, with a pronounced increase in macrophages in the alveoli and the interstitium of the lung. Haemophagocytosis was present in two patients. The alveolar pneumocytes also showed cytomegaly with granular amphophilic cytoplasm. The patient for whom full autopsy was done had atrophy of the white pulp of the spleen. Electron microscopy revealed viral particles in the cytoplasm of epithelial cells corresponding to coronavirus. SARS is associated with epithelial-cell proliferation and an increase in macrophages in the lung. The presence of haemophagocytosis supports the contention that cytokine dysregulation may account, at least partly, for the severity of the clinical disease. The case definition of SARS should acknowledge the range of lung pathology associated with this disease.
    The Lancet 06/2003; 361(9371):1773-8. DOI:10.1016/S0140-6736(03)13413-7 · 45.22 Impact Factor
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    ABSTRACT: It has been difficult to define the burden of influenza in children because of confounding by the cocirculation of respiratory syncytial virus (RSV). In Hong Kong, China, the influenza and RSV infection seasons sometimes do not overlap, thus providing an opportunity to estimate the rate of influenza-related hospitalization in a defined population, free from the effects of RSV. In a retrospective, population-based study, we estimated the influenza-associated excess rate of hospitalization among children 15 years old or younger in the Hong Kong Special Administrative Region from 1997 to 1999. Data from a single hospital with intensive use of virologic analyses for diagnosis were obtained to define and adjust for underestimation of the model. Peaks of influenza and RSV infection activity were well separated in 1998 and 1999 but overlapped in 1997. The adjusted rates of excess hospitalization for acute respiratory disease that were attributable to influenza were 278.5 and 288.2 per 10,000 children less than 1 year of age in 1998 and 1999, respectively; 218.4 and 209.3 per 10,000 children 1 to less than 2 years of age; 125.6 and 77.3 per 10,000 children 2 to less than 5 years of age; 57.3 and 20.9 per 10,000 children 5 to less than 10 years of age; and 16.4 and 8.1 per 10,000 children 10 to 15 years of age. In the subtropics, influenza is an important cause of hospitalization among children, with rates exceeding those reported for temperate regions.
    New England Journal of Medicine 01/2003; 347(26):2097-103. DOI:10.1056/NEJMoa020546 · 54.42 Impact Factor
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    ABSTRACT: Background: Malaria is one of the most important parasitic infections in humans. A sensitive diagnostic test for malaria that could be applied at the community level could be useful in programs to control the disease. The aim of the present work was to develop a simple, inexpensive molecular test for Plasmodium falciparum. Methods: Blood was collected from controls (n 100) and from patients diagnosed with falciparum malaria infection (n 102), who were recruited to the study. Heat-treated blood samples were tested by a loop- mediated isothermal amplification (LAMP) assay for P. falciparum. Results were interpreted by a turbidity meter in real time or visually at the end of the assay. To evaluate the assay, DNA from these samples was puri- fied and tested by PCR. Results from the LAMP and PCR assays were compared. Results: The LAMP assay detected P. falciparum di- rectly from heat-treated blood. The quantitative data from the assay correlated to the parasite counts obtained by blood-film microscopic analyses. When we used the PCR assay as the comparison method, the sensitivity and specificity of the LAMP assay were 95% and 99%, respectively. Conclusions: Unlike PCR, the LAMP assay does not require purified DNA for efficient DNA amplification, thereby reducing the cost and turnaround time for P. falciparum diagnosis. The assay requires only basic instruments, and assay positivity can be verified by visual inspection. © 2006 American Association for Clinical Chemistry

Publication Stats

1k Citations
190.35 Total Impact Points

Institutions

  • 2003–2012
    • The University of Hong Kong
      • • Department of Microbiology
      • • Department of Paediatrics and Adolescent Medicine
      Hong Kong, Hong Kong
  • 2003–2010
    • Lands Department of The Government of the Hong Kong Special Administrative Region
      Hong Kong, Hong Kong
  • 2003–2006
    • Queen Mary Hospital
      Hong Kong, Hong Kong