2023-10-14 05:39:24
Several flocks of sheep and cattle in the Netherlands are currently affected by bluetongue (BCF), known as bluetongue disease. Although it is not dangerous for humans, its spread throughout Europe is worrying.
Harmless to humans, potentially fatal to livestock. Two weeks following its first detection in the Netherlands, blue tongue virus was confirmed this week in 18 sheep herds and 55 cattle herds. Belgium, Switzerland but also France have been affected by an upsurge in recent months.
In fact, the virus appeared for the first time in Switzerland in 2007. In 2011, there were tens of thousands of cases throughout Europe. Thanks to a vaccine, Switzerland was able to eradicate this problem, at least temporarily. Since 2017, new cases have appeared, with new, more contagious agents such as BTV-3.
“The World Organization for Animal Health is currently reporting two “active” infectious outbreaks of BTV in France, one of the BTV-4 strain and the other of BTV-8,” said a document from the UK Department for Environment, Food and Rural Affairs dated September 29. It is estimated that around ten outbreaks have been infected in Tarn and Aveyron since last August.
No vaccine for this agent
As a reminder, FCO is an RNA viral disease that affects ruminants, sheep and cattle. It is transmitted by biting midges (Culicoides). Regarding symptoms, in animals these include hyperthermia, difficulty locomotion, oral ulcerations causing a blue tongue and hypersalivation.
Although it is not dangerous for humans, animals can die from it. The severity of the disease nevertheless depends on the species of the infected animal. Thus, it is sheep that are likely to suffer the most: rapid loss of peas, drop in wool production and mortality.
In very susceptible sheep, morbidity can reach 100%. Mortality varies between 2 and 30% on average but can go up to 70% depending on the World Organization for Animal Health. Note that there is currently no vaccine to get rid of it.
Another worrying fact is that the disease is transmitted quickly, of course, but the pathogen currently affecting the Netherlands is all the more virulent as it can have consequences on pregnant females. Depending on the stage of gestation, abortions and births of “stupid” calves and lambs (brain malformation) have been recorded in recent years, always according to the same source.
Global warming to blame?
The United Kingdom also specified in its September press release that authorities were concerned that infected midges might cross the North Sea. In particular, they monitor the winds, while modeling potential plumes of midges.
And with the abnormally mild temperatures, due to global warming which has been increasingly felt in recent years, the resurgence of this virus might be justified.
However, the insects which are vectors can only die if temperatures drop below 0°C. But winter might not be enough – in case it is actually cold – if midges have the opportunity to stay in warm places, near animals.
Note that according to Ms. Holwerda, virologist who directs the national reference laboratory for viruses Wageningen Bioveterinary Research (WBVR) in the Netherlands, we will have to wait until around May to hope for the design of a vaccine.
1697262286
#Blue #tongue #virus #deadly #disease #spreads #farm #animals
