Spatial Transmission Characteristics of the Bluetongue Virus Serotype 3 Epidemic in The Netherlands, 2023.

A devastating bluetongue (BT) epidemic caused by bluetongue virus serotype 3 (BTV-3) has spread throughout most of the Netherlands within two months since the first infection was officially confirmed in the beginning of September 2023. The epidemic comes with unusually strong suffering of infected cattle through severe lameness, often resulting in mortality or euthanisation for welfare reasons. In total, tens of thousands of sheep have died or had to be euthanised.

Manifestation of SARS-CoV-2 Infections in Mink Related to Host-, Virus- and Farm-Associated Factors, The Netherlands 2020.

SARS-CoV-2 outbreaks on 69 Dutch mink farms in 2020 were studied to identify risk factors for virus introduction and transmission and to improve surveillance and containment measures. Clinical signs, laboratory test results, and epidemiological aspects were investigated, such as the date and reason of suspicion, housing, farm size and distances, human contact structure, biosecurity measures, and presence of wildlife, pets, pests, and manure management. On seven farms, extensive random sampling was performed, and age, coat color, sex, and clinical signs were recorded.

Adaptation, spread and transmission of SARS-CoV-2 in farmed minks and associated humans in the Netherlands.

In the first wave of the COVID-19 pandemic (April 2020), SARS-CoV-2 was detected in farmed minks and genomic sequencing was performed on mink farms and farm personnel. Here, we describe the outbreak and use sequence data with Bayesian phylodynamic methods to explore SARS-CoV-2 transmission in minks and humans on farms. High number of farm infections (68/126) in minks and farm workers (>50% of farms) were detected, with limited community spread.

Occupational and environmental exposure to SARS-CoV-2 in and around infected mink farms.

Objective: Unprecedented SARS-CoV-2 infections in farmed minks raised immediate concerns regarding transmission to humans and initiated intensive environmental investigations to assess occupational and environmental exposure.

Methods: Air sampling was performed at infected Dutch mink farms, at farm premises and at nearby residential sites. A range of other environmental samples were collected from minks' housing units, including bedding materials.

SARS-CoV-2 infection in cats and dogs in infected mink farms.

Animals like mink, cats and dogs are susceptible to SARS-CoV-2 infection. In the Netherlands, 69 out of 127 mink farms were infected with SARS-CoV-2 between April and November 2020 and all mink on infected farms were culled after SARS-CoV-2 infection to prevent further spread of the virus. On some farms, (feral) cats and dogs were present.

Transmission of SARS-CoV-2 on mink farms between humans and mink and back to humans.

Animal experiments have shown that nonhuman primates, cats, ferrets, hamsters, rabbits, and bats can be infected by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In addition, SARS-CoV-2 RNA has been detected in felids, mink, and dogs in the field. Here, we describe an in-depth investigation using whole-genome sequencing of outbreaks on 16 mink farms and the humans living or working on these farms.

Highly pathogenic avian influenza subtype H5Nx clade 2.3.4.4 outbreaks in Dutch poultry farms, 2014-2018: Clinical signs and mortality.

In recent years, different subtypes of highly pathogenic avian influenza (HPAI) viruses caused outbreaks in several poultry types worldwide. Early detection of HPAI virus infection is crucial to reduce virus spread. Previously, the use of a mortality ratio threshold to expedite notification of suspicion in layer farms was proposed.

Seroprevalence of Schmallenberg virus antibodies among dairy cattle, the Netherlands, winter 2011-2012.

Infections with Schmallenberg virus (SBV) are associated with congenital malformations in ruminants. Because reporting of suspected cases only could underestimate the true rate of infection, we conducted a seroprevalence study in the Netherlands to detect past exposure to SBV among dairy cattle. A total of 1,123 serum samples collected from cattle during November 2011-January 2012 were tested for antibodies against SBV by using a virus neutralization test; seroprevalence was 72.

Bluetongue virus serotype 6 in Europe in 2008-Emergence and disappearance of an unexpected non-virulent BTV.

Bluetongue viruses (BTVs) could invade N-W Europe similar to BTV serotype 8 (BTV8/net06), since the source and route of introduction of this virus has not been solved. Therefore, the Dutch survey for Bluetongue by PCR testing was extended by further analysis of PCR positives to identify the involved BTV. In late August 2008, BTV was reported with 12 nucleotide differences in the S10 amplicon (S10 genotyping).

[Severe clinical problems lasting several weeks on a multiplier pig farm: what if it had been classical swine fever?].

In the Spring of 2009, a veterinarian reported suspected classical swine fever (CSF) on a multiplier pig farm in the southern part of The Netherlands (close to the Belgian border). Over a 5-week period there had been a number of sick sows and an excessively high percentage of stillborn and preterm piglets. Sick animals were treated with anti-inflammatory drugs and antibiotics, but did not respond as well as anticipated.

Epidemiologic characteristics of bluetongue virus serotype 8 laboratory-confirmed outbreaks in The Netherlands in 2007 and a comparison with the situation in 2006.

A major epidemic of bluetongue virus serotype 8 (BTV-8) occurred in Western Europe in 2006. During 2007 it became evident that BTV-8 had survived the winter and a re-emerging epidemic quickly developed. The objective of this study was to describe the severity and clinical impact of the BTV-8 epidemic in 2007 in The Netherlands in laboratory-confirmed outbreaks and to compare this with the situation in 2006.

Field observations during the Bluetongue serotype 8 epidemic in 2006. II. Morbidity and mortality rate, case fatality and clinical recovery in sheep and cattle in the Netherlands.

Data collected in the Netherlands during the Bluetongue serotype 8 (BTV-8) epidemic indicated that in outbreak cattle herds, predominantly dairy and nursing cows were clinically affected and not young stock, beef cattle, beef calves, or breeding animals. In outbreak sheep flocks, mainly ewes and--if present--rams, were clinically affected and not the lambs. Median morbidity rate in outbreak herds was 1.

Field observations during the bluetongue serotype 8 epidemic in 2006. I. Detection of first outbreaks and clinical signs in sheep and cattle in Belgium, France and the Netherlands.

Starting August 2006, a major epidemic of bluetongue (BT) was identified in North-West Europe, affecting The Netherlands, Belgium, Germany, Luxembourg and the North of France. It was caused by BT virus serotype 8 (BTV-8), a serotype previously unknown to the European Union (EU). In this outbreak, the virus caused clinical disease in a few individual animals within cattle herds, whereas overt clinical disease was usually restricted to sheep.

[Epidemiology of bluetongue virus serotype 8 outbreaks in the Netherlands in 2006].

In August 2006 a major epidemic of Bluetongue (BT) occurred in north-western Europe, affecting The Netherlands, Belgium, Germany, Luxemburg, and the north of France. It was caused by Br virus serotype 8 (BTV-8), a serotype previously unknown to the EU. Although clinical disease is usually restricted to sheep, this virus also caused clinical disease in a small proportion of cattle.