Comparison of norovirus genogroup I, II and IV seroprevalence among children in the Netherlands, 1963, 1983 and 2006.

Noroviruses are a major cause of acute gastroenteritis worldwide and are a genetically diverse group of viruses. Since 2002, an increasing number of norovirus outbreaks have been reported globally, but it is not clear whether this increase has been caused by a higher awareness or reflects the emergence of new genogroup II genotype 4 (GII.4) variants.

Spot the difference-development of a syndrome based protein microarray for specific serological detection of multiple flavivirus infections in travelers.

Background: The family Flaviviridae, genus Flavivirus, holds many of the world's most prevalent arboviral diseases that are also considered the most important travel related arboviral infections. In most cases, flavivirus diagnosis in travelers is primarily based on serology as viremia is often low and typically has already been reduced to undetectable levels when symptoms set in and patients seek medical attention. Serological differentiation between flaviviruses and the false-positive results caused by vaccination and cross-reactivity among the different species, are problematic for surveillance and diagnostics of flaviviruses.

Shedding of norovirus in symptomatic and asymptomatic infections.

Norovirus is the most frequent cause of acute infectious gastroenteritis and it is difficult to control in crowded environments like hospitals and nursing homes. Transmission depends on oral intake of virus deposited in the environment by infectious subjects. Data from volunteer studies indicate that virus concentrations in stool are highly variable, but systematic studies of the time-course of shedding and its individual variation are lacking.

Leflunomide as part of the treatment for multidrug-resistant cytomegalovirus disease after lung transplantation: case report and review of the literature.

Treatment of cytomegalovirus (CMV) disease in transplant patients is challenging and, with antiviral resistance to first-line drugs, it remains uncertain which treatment algorithm to follow. Some data suggest that leflunomide, a pyrimidine synthesis inhibitor, can be used to treat resistant CMV infections. We report a 57-year-old CMV immunoglobulin-G (IgG)-seronegative woman, who received a bilateral lung transplant (LuTx) from a CMV IgG-positive donor with CMV primary disease.

Diagnostic performance of selected commercial HEV IgM and IgG ELISAs for immunocompromised and immunocompetent patients.

Background: Hepatitis E virus (HEV) genotype 3 is recognised as an emerging pathogen in industrialised countries. The currently commercially available HEV-specific enzyme linked immunosorbent assays (ELISAs) are primarily designed for the detection of antibodies against genotypes 1 (Burma) and 2 (Mexico) and may not sensitively detect HEV genotypes 3 or 4.

Objectives: This study aimed to evaluate the analytical and clinical performances of eight commercially available HEV serum antibody immunoglobulin M (IgM)- and immunoglobulin G (IgG)-specific ELISAs for genotype 1 and 3 HEV infections in a clinical setting and to study the antibody responses against HEV of immunocompromised versus immunocompetent patient groups.

Cytomegalovirus prophylaxis in pediatric kidney transplantation: the Dutch experience.

Many children receiving a kidney transplant are seronegative for CMV and therefore, highly susceptible to a primary CMV infection. This study aims at evaluating incidence, time of occurrence, and severity of CMV infection in the first year post-transplantation in relation to different types of CMV prophylaxis. Transplantations in three centers in the Netherlands between 1999 and 2010 were included.

P2 domain profiles and shedding dynamics in prospectively monitored norovirus outbreaks.

Background: Norovirus P2 domain is commonly used to extrapolate transmission within an outbreak (OB) setting. The current definition is that transmission among cases is considered to be proven when no sequence variation is found.

Objectives: Previous studies have shown a high mutation rate and errors during replication of the norovirus genome, therefore the validity of this criterion must be evaluated.

Imported scrub typhus in The Netherlands.

Two cases of travel-acquired scrub typhus imported in the Netherlands are described. The characteristic eschar was absent in both cases. One case acquired scrub typhus in non-rural surroundings in India, highlighting that scrub typhus must also be considered a (sub) urban zoonosis.

Unrecognized norovirus infections in health care institutions and their clinical impact.

Noroviruses (NoVs) have emerged as the leading cause of acute viral gastroenteritis (GE) in humans. Although diagnostic facilities have greatly improved, significant underdiagnosis of NoV in hospitals may still occur, thereby increasing clinical burden and nosocomial spread. We evaluated the underdiagnosis of sporadic NoV infections in a tertiary care hospital and estimated its clinical impact.

An outbreak of severe respiratory tract infection caused by human metapneumovirus in a residential care facility for elderly in Utrecht, the Netherlands, January to March 2010.

Recognition of infections with human metapneumovirus (HMPV) among institutionalised elderly is rising. When HMPV was found to be the causative agent of an outbreak of pneumonia in a residential care facility for elderly in the Netherlands, an elaborate outbreak investigation was set up, including active surveillance for new cases. From clinical cases, defined by fever (> 38°C) and symptoms of respiratory tract infections, respiratory samples for analyses of viral pathogens by real-time Reverse Transcriptase Polymerase Chain Reaction (rRT-PCR) and blood samples for determination of HMPV-specific IgM and IgG antibody titres were taken.

A case of rickettsialpox in Northern Europe.

We report the first case of rickettsialpox caused by Rickettsia akari in the Netherlands. The diagnosis was suspected based on clinical grounds and was confirmed by Western blot analysis with cross-adsorption. Because the arthropod vector (Liponyssoides sanguineus) is ubiquitous, we suspect that the disease is under-diagnosed in non-endemic areas.

A five-year perspective on the situation of haemorrhagic fever with renal syndrome and status of the hantavirus reservoirs in Europe, 2005-2010.

Hantavirus infections are reported from many countries in Europe and with highly variable annual case numbers. In 2010, more than 2,000 human cases were reported in Germany, and numbers above the baseline have also been registered in other European countries. Depending on the virus type human infections are characterised by mild to severe forms of haemorrhagic fever with renal syndrome.

Molecular diagnostics of Rickettsia africae infection in travelers returning from South Africa to The Netherlands.

Background: African tick-bite fever (ATBF) is frequently diagnosed in The Netherlands in travelers returning from South Africa. It is caused by Rickettsia africae and diagnosis is based on travel history and clinical presentation and usually confirmed by detecting serum antibodies against rickettsiae of the spotted fever group. However, these typically occur late in the course of the disease, and a mild clinical course or early antibiotic treatment can diminish antibody production.

Evaluation of the antiviral response to zanamivir administered intravenously for treatment of critically ill patients with pandemic influenza A (H1N1) infection.

A retrospective nationwide study on the use of intravenous (IV) zanamivir in patients receiving intensive care who were pretreated with oseltamivir in the Netherlands was performed. In 6 of 13 patients with a sustained reduction of the viral load, the median time to start IV zanamivir was 9 days (range, 4-11 days) compared with 14 days (range, 6-21 days) in 7 patients without viral load reduction (P = .052).

Oseltamivir-resistant pandemic A(H1N1) 2009 influenza viruses detected through enhanced surveillance in the Netherlands, 2009-2010.

Enhanced surveillance of infections due to the pandemic A(H1N1) influenza virus, which included monitoring for antiviral resistance, was carried out in the Netherlands from late April 2009 through late May 2010. More than 1100 instances of infection with the pandemic A(H1N1) influenza virus from 2009 and 2010 [A(H1N1) 2009] distributed across this period were analyzed. Of these, 19 cases of oseltamivir-resistant virus harboring the H275Y mutation in the neuraminidase (NA) were detected.

A comparison of two assays for quantification of Hepatitis B surface Antigen in patients with chronic hepatitis B.

Background And Objectives: Serum Hepatitis B surface Antigen (HBsAg) levels correlate with hepatitis B virus intrahepatic covalently closed circular DNA and may predict response to treatment. Currently, 2 commercial platforms are available for HBsAg quantification in clinical practice, the Architect HBsAg QT and the Elecsys HBsAg. We aimed to directly compare the results of these assays.

Using molecular epidemiology to trace transmission of nosocomial norovirus infection.

Nosocomial norovirus (NoV) infection is common and may lead to complications in vulnerable hospitalized patients. Understanding sources and modes of transmission of noroviruses within health care settings will support the design of evidence-based strategies for reducing introduction and further spread. We sequenced a highly variable segment of the genome to identify possible clusters in patients with and without acute gastroenteritis who were hospitalized in the period 2002-2007.

Chronic shedders as reservoir for nosocomial transmission of norovirus.

Norovirus (NoV) infection in immunocompromised patients may lead to prolonged norovirus shedding. Here, we demonstrate the involvement of three chronic shedders in hospital outbreaks. Combined epidemiological and molecular evidence suggests that in one case, NoV transmission occurred at least 17 days after the first diagnosis.

Quantification of viral DNA and liver enzymes in plasma improves early diagnosis and management of herpes simplex virus hepatitis.

Herpes simplex virus (HSV) hepatitis is a rare and potential life-threatening disease. The diagnosis of HSV hepatitis is hampered by its indifferent clinical presentation, which necessitates confirmatory laboratory data to identify HSV in the affected liver. However, liver biopsies are often contraindicated in the context of coagulopathy, are prone to sampling errors and have low sensitivity in mild HSV hepatitis cases.

BK virus nephropathy in an immunodeficient patient with chronic lymphocytic leukemia.

Background: BK virus, genus polyomavirus, is known as an important cause of nephropathy (BKVN) in renal transplant patients. Cases of BKVN in native kidneys are rare.

Objectives: To report a case of BKVN in a patient with chronic lymphocytic leukemia (CLL) and to examine viral and immune parameters.

Norovirus in a Dutch tertiary care hospital (2002-2007): frequent nosocomial transmission and dominance of GIIb strains in young children.

We report a retrospective analysis of norovirus (NoV) infections occurring in patients of a tertiary care hospital during five winter seasons (2002/03 to 2006/07). Data were compared with national surveillance data and with corresponding data for rotavirus. Between July 2002 and June 2007, faecal specimens from 221 (9.

High prevalence of prolonged norovirus shedding and illness among hospitalized patients: a model for in vivo molecular evolution.

During a 2-year survey in an academic hospital, 8 (8.4%) of all norovirus (NoV)-positive patients showed prolonged norovirus illness and shedding (duration, 21-182 days). All patients had underlying illnesses, resulting in some level of immunodeficiency in 5.

The value of Chlamydia trachomatis-specific IgG antibody testing and hysterosalpingography for predicting tubal pathology and occurrence of pregnancy.

We assessed two diagnostic methods, Chlamydia trachomatis-specific IgG and hysterosalpingography (HSG), as a screening test for the likelihood of tubal damage or occurrence of pregnancy before laparoscopy in 178 subfertile women who were randomly assigned to HSG followed by laparoscopy or immediate laparoscopy. The diagnostic accuracy and prognostic value of both C. trachomatis-specific IgG antibody testing and HSG are comparable but show poor performance.

Fourth human parechovirus serotype.

We identified a novel human parechovirus (HPeV) type (K251176-02) from a neonate with fever. Analysis of the complete genome showed K251176-02 to be a new HPeV genotype. Since K251176-02 could not be neutralized with antibodies against known HPeV serotypes 1-3, it should be classified as a fourth HPeV serotype.