Avian influenza A virus (H7N7) associated with human conjunctivitis and a fatal case of acute respiratory distress syndrome.

Highly pathogenic avian influenza A viruses of subtypes H5 and H7 are the causative agents of fowl plague in poultry. Influenza A viruses of subtype H5N1 also caused severe respiratory disease in humans in Hong Kong in 1997 and 2003, including at least seven fatal cases, posing a serious human pandemic threat. Between the end of February and the end of May 2003, a fowl plague outbreak occurred in The Netherlands.

Influenza vaccination in children with asthma: randomized double-blind placebo-controlled trial.

There is little evidence that influenza vaccination reduces asthma exacerbations. We determined whether influenza vaccination is more effective than placebo in 6-18-year-old children with asthma. We performed a randomized, double-blind, placebo-controlled trial.

Prevalence and clinical symptoms of human metapneumovirus infection in hospitalized patients.

During a 17-month period, we performed retrospective analyses of the prevalence of and clinical symptoms associated with human metapneumovirus (hMPV) infection, among patients in a university hospital in The Netherlands. All available nasal-aspirate, throat-swab, sputum, and bronchoalveolar-lavage samples (N=1515) were tested for hMPV RNA by reverse-transcriptase polymerase chain reaction. hMPV RNA was detected in 7% of samples from patients with respiratory tract illnesses (RTIs) and was the second-most-detected viral pathogen in these patients during the last 2 winter seasons.

Pretreatment intrahepatic CD8+ cell count correlates with virological response to antiviral therapy in chronic hepatitis C virus infection.

We analyzed the relationship between virological response and baseline immune factors in 17 patients chronically infected with hepatitis C virus (HCV) who received interferon-alpha-ribavirin therapy for 26 weeks. The number of intrahepatic CD8(+) cells present in the portal tract before the start of treatment was found to be significantly higher in patients who responded to treatment than in nonresponders. The relationship between portal CD8(+) cell counts and the response to therapy could be described by a logistic curve.

Human metapneumovirus infection in Thai children.

Human metapneumovirus (hMPV) associated with clinical respiratory tract infection (RTI) in children was first isolated in The Netherlands. Of 120 Thai paediatric patients with RTI examined, 5 cases (4.2%) showed detectable hMPV based on N-gene-specific RT-PCR.

Virology: SARS virus infection of cats and ferrets.

Unlabelled: The reservoir of the coronavirus isolated from patients with severe acute respiratory syndrome (SARS) is still unknown, but is suspected to have been a wild animal species. Here we show that ferrets () and domestic cats () are susceptible to infection by SARS coronavirus (SCV) and that they can efficiently transmit the virus to previously uninfected animals that are housed with them. The observation that these two distantly related carnivores can so easily be infected with the virus indicates that the reservoir for this pathogen may involve a range of animal species.

Clinical, immunological and virological response to different antiretroviral regimens in a cohort of HIV-2-infected patients.

Objective: To assess the clinical, immunological and virological response and the emergence of resistance towards antiretroviral therapy (ART) in a cohort of HIV-2-infected patients.

Design: Observational study.

Patients: HIV-2-infected patients residing in the Netherlands.

Effects of human metapneumovirus and respiratory syncytial virus antigen insertion in two 3' proximal genome positions of bovine/human parainfluenza virus type 3 on virus replication and immunogenicity.

A live attenuated bovine parainfluenza virus type 3 (PIV3), harboring the fusion (F) and hemagglutinin-neuraminidase (HN) genes of human PIV3, was used as a virus vector to express surface glycoproteins derived from two human pathogens, human metapneumovirus (hMPV) and respiratory syncytial virus (RSV). RSV and hMPV are both paramyxoviruses that cause respiratory disease in young children, the elderly, and immunocompromised individuals. RSV has been known for decades to cause acute lower respiratory tract infections in young children, which often result in hospitalization, while hMPV has only been recently identified as a novel human respiratory pathogen.

Detection of immune-complex-dissociated nonstructural-1 antigen in patients with acute dengue virus infections.

Accurate and timely diagnosis of dengue virus (DEN) infections is essential for the differential diagnosis of patients with febrile illness and hemorrhagic fever. In the present study, the diagnostic value of a newly developed immune-complex dissociated nonstructural-1 (NS-1) antigen dot blot immunoassay (DBI) was compared to a commercially available DEN antigen detection kit (denKEY Blue kit; Globio Co., Beverly, Mass.

Population dynamics of rapid fixation in cytotoxic T lymphocyte escape mutants of influenza A.

The dynamics of cellular immunity against pathogens, and its interaction with the human MHC system, is a key area for empirical research, both within individual hosts and in population genetic surveys. However, in contrast with humoral immunity, the dynamics of cellular immunity have not been modeled at the population level. Here, we address this lacuna with a model of recently observed dramatic invasions of cytotoxic T lymphocyte escape mutants in human influenza A.

RSV-induced bronchiolitis but not upper respiratory tract infection is accompanied by an increased nasal IL-18 response.

The aim of this study was to investigate potential differences in the local nasal immune response between bronchiolitis and upper respiratory tract infection induced by respiratory syncytial virus (RSV). Nasal brush samples were obtained from 14 infants with RSV bronchiolitis and from 8 infants with RSV upper respiratory tract infection. The samples were taken during infection (acute phase) and 2-4 weeks later (convalescent phase).

Vaccination against measles: a neverending story.

Measles, a highly contagious viral disease, is a major childhood killer in developing countries, accounting for almost 1 million deaths every year globally. Measles virus normally does not cause a persistent infection, no animal reservoir for measles virus exists, no vector is involved in its spread, only one serotype exists, the virus is antigenically stable and vaccination with the currently used live attenuated vaccines proved to be highly effective in preventing disease. Therefore, theoretically measles should be considered eradicable.

Human papillomavirus infection in men who have sex with men participating in a Dutch gay-cohort study.

Background: To develop strategies for prevention and early treatment of human papillomavirus (HPV) anal and penile cancer, a better understanding of related sexual behavior risk factors is needed.

Goal: The goal of this study was to establish the prevalence of anal and coronal sulcus HPV in a group of men who have sex with men participating in a Dutch gay-cohort study, to identify risk factors associated with HPV infection in this group, and to investigate the presence of identical HPV types in couples with stable relationships.

Study Design: A cross-sectional study of 241 HIV-negative and 17 HIV-positive men who have sex with men visiting the sexually transmitted disease clinic of the Erasmus MC for a regular and scheduled examination.

Newly discovered coronavirus as the primary cause of severe acute respiratory syndrome.

Background: The worldwide outbreak of severe acute respiratory syndrome (SARS) is associated with a newly discovered coronavirus, SARS-associated coronavirus (SARS-CoV). We did clinical and experimental studies to assess the role of this virus in the cause of SARS.

Methods: We tested clinical and postmortem samples from 436 SARS patients in six countries for infection with SARS-CoV, human metapneumovirus, and other respiratory pathogens.

Prevalence and genotypes of hepatitis C virus infection among drug addicts and blood donors in Thailand.

Hepatitis C virus (HCV) is an infectious agent that has the potential to cause chronic liver disease, cirrhosis and hepatocellular carcinoma. We determined the prevalence and genotypes of HCV infection among groups of drug addicts: intravenous drug users (n = 134), methamphetamine users (n = 100), inhaled-drugs users (n = 19) and alcoholics (n = 50); a group of blood donors acted as a control. The control group consisted of 179 randomly-selected anti-HCV positive samples: these were subjected to HCV RNA screening and genotyping.

Aetiology: Koch's postulates fulfilled for SARS virus.

Unlabelled: Severe acute respiratory syndrome (SARS) has recently emerged as a new human disease, resulting globally in 435 deaths from 6,234 probable cases (as of 3 May 2003). Here we provide proof from experimental infection of cynomolgus macaques () that the newly discovered SARS-associated coronavirus (SCV) is the aetiological agent of this disease. Our understanding of the aetiology of SARS will expedite the development of diagnostic tests, antiviral therapies and vaccines, and may allow a more concise case definition for this emerging disease.

Immunogenicity and efficacy of recombinant subunit vaccines against phocid herpesvirus type 1.

Phocid herpesvirus type 1 (PhHV-1) is an alpha-herpesvirus that causes significant morbidity and mortality among young and immunocompromised harbour seals (Phoca vitulina) and therefore represents a major problem for seal rehabilitation centres. Consequently, there is a need for a safe and effective PhHV-1 vaccine. We tested an ISCOM-based recombinant PhHV-1 gB vaccine alone (gB) or with the addition of recombinant PhHV-1 gD (gBD) for (i).

Serological reactivity of baculovirus-expressed Ebola virus VP35 and nucleoproteins.

Ebola virus (EBOV) is a member of the family Filoviridae and is classified as a biosafety level 4 virus. This classification makes the preparation of antigen and performance of diagnostic assays time-consuming and complicated. The objective of this study was to evaluate the value of EBOV immunoassays based on recombinant nucleoprotein (r-NP) and recombinant VP35 (r-VP35) using large serum panels of African origin and from primates.

Characterization of a novel coronavirus associated with severe acute respiratory syndrome.

In March 2003, a novel coronavirus (SARS-CoV) was discovered in association with cases of severe acute respiratory syndrome (SARS). The sequence of the complete genome of SARS-CoV was determined, and the initial characterization of the viral genome is presented in this report. The genome of SARS-CoV is 29,727 nucleotides in length and has 11 open reading frames, and its genome organization is similar to that of other coronaviruses.

Comparative study of different methods to genotype hepatitis C virus type 6 variants.

Hepatitis C virus (HCV) genotype 6a is found frequently in Southeast Asia. In Thailand, however, genotype 6 variants may exist which posses a genotype 1 like sequence in the 5' non-coding region. In order to genotype correctly these viruses, four different methods; INNO-LiPA assay, two RFLP assays on the core region (using different restriction enzymes) and phylogenetic analysis of the core sequences were compared.

Identification of a novel coronavirus in patients with severe acute respiratory syndrome.

Background: The severe acute respiratory syndrome (SARS) has recently been identified as a new clinical entity. SARS is thought to be caused by an unknown infectious agent.

Methods: Clinical specimens from patients with SARS were searched for unknown viruses with the use of cell cultures and molecular techniques.

Animal influenza virus surveillance.

Influenza surveillance studies in humans and animals performed for many years have provided a wealth of data on the ecology and evolution of influenza viruses and their public health related and economical impact. Here we provide a brief overview of some of the data from the past and give our view on how the continued and intensified animal influenza virus surveillance may aid in the early recognition and management of outbreaks in the future.

Elevated levels of total and dengue virus-specific immunoglobulin E in patients with varying disease severity.

The kinetics of total and dengue virus-specific immunoglobulin E (IgE) were studied in serial serum samples obtained from 168 patients, 41 of whom suffered from primary dengue virus infection and 127 suffered from secondary dengue virus infection. Seventy-one patients were classified as dengue fever, 30 as dengue hemorrhagic fever, and 67 as dengue shock syndrome. A control group included single serum samples from patients with a herpes virus infection (n = 14), non-dengue febrile patients (n = 10), and healthy blood donors (n = 10).

Restricted T cell receptor beta-chain variable region protein use by cornea-derived CD4+ and CD8+ herpes simplex virus-specific T cells in patients with herpetic stromal keratitis.

Herpetic stromal keratitis (HSK) is a T helper type 1 cell-mediated inflammatory disease triggered by herpes simplex virus (HSV) infection of the cornea. In contrast to animal models of HSK, little is known about the role of T cells in human HSK. The phenotypes and repertoires of HSV-specific T cells recovered from the corneas of 12 patients with HSK were determined by flow cytometry.