A retrospective serological survey on human babesiosis in Belgium.

In Europe, most clinical babesiosis cases in humans have been attributed to Babesia divergens and Babesia sp. EU1. Babesia microti infection of humans occurs mainly in the United States; although a case of autochthonous B. microti infection and serological evidence of infection have been reported in Europe. The Indirect Fluorescent Antibody Test was used to screen sera from 199 anonymous Belgian patients with history of tick bite and clinical symptoms compatible with a tick-borne disease. The serological screen detected positive reactivity in 9% (n = 18), 33.2% (n = 66), and 39.7% (n = 79) of the samples against B. microti, B. divergens, and Babesia sp. EU1, respectively. Thus, evidence of contact among three potentially zoonotic species of Babesia and humans has been confirmed in Belgium. Preventive action and development of better diagnostic tools should help in prevention of clinical cases and to clarify the true burden of such infection for individuals and public health.

The Presence of Borrelia miyamotoi, A Relapsing Fever Spirochaete, in Questing Ixodes ricinus in Belgium and in The Netherlands.

Borrelia miyamotoi is a tick-borne bacterium that may cause relapsing fever in humans. As this pathogen has been discovered in Europe only recently, only little is known about its local impact on human health and its spatial distribution. In this study, we show the results of PCR screenings for B. miyamotoi in flagged Ixodes ricinus from Belgium and the Netherlands. B. miyamotoi was detected in nine of thirteen, and three of five locations from the Netherlands and Belgium, respectively. These outcomes indicate that B. miyamotoi is more spread than previously thought. The mean infection rate B. miyamotoi was 1.14% for Belgium and 3.84% for the Netherlands.

Diagnosis of human granulocytic anaplasmosis in Belgium by combining molecular and serological methods.

We report here one new, hospitalized case of Anaplasma phagocytophilum in Belgium. The clinical presentation of anaplasmosis, its treatment and the molecular and serological relevant laboratory methods are briefly developed.

Foci report on indigenous Dermacentor reticulatus populations in Belgium and a preliminary study of associated babesiosis pathogens.

The occurrence of autochthonous clinical cases of canine and equine babesiosis in Belgium during the last two decades suggests that the vector of the pathogens responsible for these diseases, Dermacentor reticulatus (Ixodida: Ixodidae), may be present in this country. Consequently, evidence for the presence of this tick species in different locations within Belgium was investigated. Four different locations were monitored by flagging in 2010; these included the locations at which D. reticulatus was previously found on a dog in 2009 and on two red deer in 2007. Two different species of tick were identified, Ixodes ricinus (Ixodida: Ixodidae) and D. reticulatus. A total of 282 D. reticulatus adult ticks (98 males, 184 females) were collected from the four sites. Ticks were found mainly from early March until the end of May and a peak in activity was apparent in March. A Babesia spp. (Piroplasmida: Babesiidae) genus-specific polymerase chain reaction test based on the amplification of a fragment of the 18S rRNA gene was used to investigate the potential presence of Babesia spp. All DNA extracts isolated from the total tick samples yielded negative results. Additional studies to accurately determine the distribution and vectorial capacity of this important tick species in Belgium are warranted.

Sero-epidemiological study of the presence of hantaviruses in domestic dogs and cats from Belgium.

Hantaviruses are worldwide rodent-borne pathogens infecting humans and other animals mainly through inhalation of aerosols contaminated with rodent excreta. Few data are available on hantavirus serology and geographical distribution in dogs and cats. We therefore screened sera from pet dogs (N=410) and cats (N=124) in two regions of Belgium, using IgG ELISA and IFA. We analysed the effect of the owner's address as well as pet gender and age on hantavirus status. Hantavirus antibodies were found in both species with a significantly higher seroprevalence in cats than in dogs (16.9% vs. 4.9%, P=0.001). More dogs were infected in highly forested southern Belgium (harbouring more rodents) than in northern Belgium (10.5% vs. 3.0%, P=0.002). In the south, hantavirus sero-positive cats were found in more densely forested localities than sero-negatives ones were (P=0.033). These results are consistent with the ecological variations of hantavirus risks in humans.

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. The member laboratories of the European Network for diagnostics of Imported Viral Diseases present here an overview of the progression of human cases in the period from 2005 to 2010. Further we provide an update on the available diagnostic methods and endemic regions in their countries, with an emphasis on occurring virus types and reservoirs.

Pathogenicity and virulence of the present hantaviruses in Bosnia and Herzegovina: the impact on renal function.

Dobrava (DOBV) and Puumala (PUUV) viruses are endemic throughout the Balkans and cause haemorrhagic fever with renal syndrome (HFRS). The aim of this study was to assess the impact of two different hantaviruses on renal function in HFRS patients during the acute stage of illness. We also aimed to assess the DOBV and PUUV distribution between symptomatic HFRS patients and asymptomatic hantavirus antibody-positive subjects. The study included 264 symptomatic HFRS patients and 63 asymptomatic hantavirus antibody-positive healthy subjects. In our study, 131 (49.6%) HFRS patients were regarded as PUUV- and 69 (26.1%) as DOBV-infected patients, while in 64 (24.2%) of HFRS patients that showed all clinical and biochemical signs of HFRS, the causal hantavirus could not be determined with commercially available tests. DOBV-infected patients were associated with more requirements for haemodialysis treatment, lower diuresis and higher serum creatinine and urea values compared to PUUV-infected patients. PUUV was significantly predominant in asymptomatic hantavirus antibody-positive subjects (69.8%) compared to HFRS patients. DOBV was present in 17.5% of asymptomatic subjects and, interestingly, the preferential hantavirus serotype could not be determined in 12.7% of the asymptomatic antibody-positive subjects.

Hantavirus outbreak in Western Europe: reservoir host infection dynamics related to human disease patterns.

Within Europe, Puumala virus (PUUV) is the causal agent of nephropathia epidemica (NE) in humans, a zoonotic disease with increasing significance in recent years. In a region of Belgium with a historically high incidence of NE, bank voles (the PUUV reservoir hosts), were monitored for PUUV IgG antibody prevalence in nine study sites before, during, and after the highest NE outbreak recorded in Belgium in 2005. We found that the highest numbers of PUUV IgG-positive voles coincided with the peak of NE cases at the regional level, indicating that a PUUV epizootic in bank voles directly led to the NE outbreak in humans. On a local scale, PUUV infection in voles was patchy and not correlated to NE incidence before the epizootic. However, during the epizootic period PUUV infection spread in the vole populations and was significantly correlated to local NE incidence. Initially, local bank-vole numbers were positively associated with local PUUV infection risk in voles, but this was no longer the case after the homogeneous spreading of PUUV during the PUUV outbreak.

Hantavirus disease (nephropathia epidemica) in Belgium: effects of tree seed production and climate.

Recently, human cases of nephropathia epidemica (NE) due to Puumala virus infection in Europe have increased. Following the hypothesis that high reservoir host abundance induces higher transmission rates to humans, explanations for this altered epidemiology must be sought in factors that cause bank vole (Myodes glareolus) abundance peaks. In Western Europe, these abundance peaks are often related to high tree seed production, which is supposedly triggered by specific weather conditions. We evaluated the relationship between tree seed production, climate and NE incidence in Belgium and show that NE epidemics are indeed preceded by abundant tree seed production. Moreover, a direct link between climate and NE incidence is found. High summer and autumn temperatures, 2 years and 1 year respectively before NE occurrence, relate to high NE incidence. This enables early forecasting of NE outbreaks. Since future climate change scenarios predict higher temperatures in Europe, we should regard Puumala virus as an increasing health threat.

Situation of hantavirus infections and haemorrhagic fever with renal syndrome in European countries as of December 2006.

Hantavirus infections are widely distributed in Europe with the exception of the far north and the Mediterranean regions. The underlying causes of varying epidemiological patterns differ among regions: in western and central Europe epidemics of haemorrhagic fever with renal syndrome (HFRS) caused by hantavirus infections follow mast years with increased seed production by oak and beech trees followed by increased rodent reproduction. In the northern regions, hantavirus infections and HFRS epidemics occur in three to four year cycles and are thought to be driven by prey - predator interactions. Hantavirus infections and HFRS seem to be on the increase in Europe, partly because of better diagnostics, partly perhaps due to environmental changes. Unfortunately, hantavirus infections are still heavily under-diagnosed in many European countries. Here we report the results of a survey conducted in 2007 amongst the member laboratories of the European Network for diagnostics of Imported Viral Diseases (ENIVD).

Haemorrhagic Fever with Renal Syndrome: an analysis of the outbreaks in Belgium, France, Germany, the Netherlands and Luxembourg in 2005.

This article aims to describe the Haemorrhagic Fever with Renal Syndrome (HFRS) situation in 2005 in five neighbouring countries (Belgium, France, Germany, the Netherlands and Luxembourg) and define the most affected areas. The 2005 HFRS outbreaks in these countries were the most significant in the region since 1990, with a total of 1,114 confirmed cases. The main feature of the epidemic was the extension of the known endemic area in several of the affected countries, with the involvement of urban areas for the first time. A significant increase in the number of cases was noted for the first time in the province of Liège in Belgium and in the Jura department in France.

Molecular and serological evidence for Anaplasma platys and Babesia sp. infection in a dog, imported in Belgium, from Southern Spain.

This case report describes a dog suffering from a co-infection with Babesia and Anaplasma parasites. Anaplasma platys was found to be responsible for the anaplasmosis by molecular biology techniques, while microscopical and serological evidence was found for a coexistent babesiosis, although this could not be confirmed by polymerase chain reaction. Moreover, the possible risk of import of exotic pathogens is highlighted.

Quality assurance for the diagnostics of viral diseases to enhance the emergency preparedness in Europe.

The threat posed by emerging and re-emerging communicable diseases and, more recently, by the intentional release of infectious agents in a susceptible population, has been receiving considerable attention at the national and international levels. Public health efforts to strengthen disease detection, surveillance and control have been intensified. However, clinicians and clinical microbiology laboratories play an important role in the early detection of disease, the identification of the putative agent, and notification of the appropriate authorities. To be effective in this role, laboratories must be specially prepared to handle viral agents safely, and need, among other things, the appropriate rapid and sensitive diagnostic tests. In 1998 the European Network for Diagnostics of 'Imported' Viral Diseases (ENIVD) was established. ENIVD presently comprises, as permanent members, 44 expert laboratories in 21 European Union (EU) member states and 4 non-EU countries and is one of the networks on infectious diseases funded by the European Commission. ENIVD fulfils many of the important tasks required for the surveillance and control of imported, rare and emerging viral infections such as the exchange of expertise and the organisation of external quality assurance (EQA) programmes, both of which are needed to improve diagnostics. Here, we summarise the data generated by recent EQA activities focussed on the diagnostics of infections with hantavirus, dengue virus, filovirus, Lassa virus, orthopox virus and the SARS-coronavirus (SARS-CoV). These were carried out between 1999 and 2004 and involved 93 laboratories from 41 countries, including laboratories from additional countries outside of Europe. Particularly the EU-candidate countries and Eastern neighbouring countries will be invited to join the network in the near future. A public website is available at http://www.enivd.de.

Quality assurance for the diagnostics of viral diseases to enhance the emergency preparedness in Europe.

The threat posed by emerging and re-emerging communicable diseases and, more recently, by the intentional release of infectious agents in a susceptible population, has been receiving considerable attention at the national and international levels. Public health efforts to strengthen disease detection, surveillance and control have been intensified. However, clinicians and clinical microbiology laboratories play an important role in the early detection of disease, the identification of the putative agent, and notification of the appropriate authorities. To be effective in this role, laboratories must be specially prepared to handle viral agents safely, and need, among other things, the appropriate rapid and sensitive diagnostic tests. In 1998 the European Network for Diagnostics of "Imported" Viral Diseases (ENIVD) was established. ENIVD presently comprises, as permanent members, 44 expert laboratories in 21 European Union (EU) member states and 4 non-EU countries and is one of the networks on infectious diseases funded by the European Commission. ENIVD fulfils many of the important tasks required for the surveillance and control of imported, rare and emerging viral infections such as the exchange of expertise and the organisation of external quality assurance (EQA) programmes, both of which are needed to improve diagnostics. Here, we summarise the data generated by recent EQA activities focussed on the diagnostics of infections with hantavirus, dengue virus, filovirus, Lassa virus, orthopox virus and the SARS-coronavirus (SARS-CoV). These were carried out between 1999 and 2004 and involved 93 laboratories from 41 countries, including laboratories from additional countries outside of Europe. Particularly the EU-candidate countries and Eastern neighbouring countries will be invited to join the network in the near future. A public website is available at http://www.enivd.de.

Hantavirus Puumala infection as a cause of fever of unknown origin in a child.

Hantavirus infection due to Puumala virus causes nephropathica epidemica, a disorder characterized by fever, haematological abnormalities, mild renal dysfunction and ophthalmological abnormalities. The prevalence in most European countries is low, but the virus can be endemic. In children, hantavirus infection is rare. This paper describes a young girl diagnosed with hantavirus infection. The patient presented with high fever, proteinuria, haematuria and eye lesions, but other typical hallmarks of the disease, such as thrombocytopenia and renal dysfunction, were absent. This case report demonstrates the need to consider the diagnosis of hantavirus infection in children with prolonged fever of unknown origin. The diagnosis is based on serological tests.

Seoul hantavirus in Europe: first demonstration of the virus genome in wild Rattus norvegicus captured in France.

Although rats (Rattus rattus or Rattus norvegicus) worldwide have been found to carry Seoul hantavirus, there are at present only a very few reports of confirmed human Seoul hantavirus infections outside Asia, where the virus, in certain areas, is responsible for approximately 25% of the human hantavirus infections. In Europe, no confirmed human infections outside laboratories have been described, and although rats occasionally have been found to be antibody positive, the viral genome has not been demonstrated in these animals. The present report describes the first confirmed finding of Seoul hantavirus in R. norvegicus captured in Europe.

Human Granulocytic Ehrlichiosis in Belgium: an underestimated cause of disease.

OBJECTIVES: Human Granulocytic Ehrlichiosis (HGE) is a recently discovered zoonosis and, in Europe, not always included in laboratory testing when a patient presents with a history of tick bite. The available serology results indicate that HGE should be included in the screening panel when a tick-borne disease is suspected. METHODS: Serological methods were applied; i.e. indirect immunofluorescence and Western Blot analysis. Sixty-five serum samples from 47 patients were analysed, of six patients sequential samples were available. RESULTS: 33.8% of the submitted samples were found positive in indirect immunofluorescence, Western Blot confirmed 46.1% of these positive samples. CONCLUSIONS: Although the causative agent and the vector for HGE, Ixodes ticks, are present in Belgium, serology for HGE is seldom solicited. Ehrlichiosis is apparently not always considered as a plausible or possible cause for illness, even when the patient presents with a history of tick bite. We present here a, true be it, incomplete picture of the present situation in Belgium, but nevertheless indicating that it is warranted to test patients with a history of tick bite not only for Lyme disease, but also for HGE.

Distribution of hantavirus foci in Belgium.

During 1999 and 2000, we performed rodent captures on 15 sites all over Belgium to evaluate the presence of hantaviruses in local rodent populations. Viral antibody and RNA detection was performed by ELISA/focus reduction neutralisation test and RT-PCR, respectively. We found hantavirus-positive rodents on 13 out of 15 trapping sites and 3 rodent species were found positive for hantavirus infection. Apart from Puumala virus that was carried by Clethrionomys glareolus, 2 additional rodent species, Microtus arvalis and Apodemus sylvaticus, were found antibody- and/or RNA-positive.