Belgium: (Non-Reportable) LPAI H3N1 Extends To 33 Farms

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On Monday, in Belgium: Non-Reportable LPAI H3N1 In Poultry, we looked at a recent outbreak of a Low Path avian H3N1 virus - which at the time had affected 16 farms.

Fast forward three days and that number has more than doubled, with the Boerenbond - a farmer's union in Belgium - now reporting 33 farm outbreaks. 

Normally LPAI H3 viruses produce little if any signs or symptoms in poultry, and are considered low consequence infections. These recent outbreaks in Belgium, however, are producing substantial mortality (up to 60%), raising questions about possible co-infections or changes to the virus.

Complicating matters, only HPAI and LPAI H5 and H7 viruses are currently reportable to the OIE (see Terrestrial Animal Code Article 10.4.1.), and local protocols for dealing with a low path non-H5 or H7 avian virus are ambiguous at best.

With mounting losses, farmers are asking for the government's compensation fund to step in, but it apparently only covers OIE listed poultry viruses.

We've two translated reports from the Boerenbond.  First a report dated the 8th with the latest totals and calls (again) for a coordinated response, and another from the 7th which discusses - among other things - the possibility of the wind spreading the virus from farm to farm.

I'll have more after the break. 

Bird flu: What should you know?

Wouter Wytynck, advisor Animal breeding, Research Farmers Union

Update May 8th 2019.

Debriefing consultation Sanitary Fund and AFSCA. In recent days, the number of infections with low pathogenic influenza type H3 widened to 33. The losses to the affected farms are large and to date we grope still in the dark or there may be another pathogen in the game which reinforces the disease.

Despite the fact that this type of virus are legally should not contested, Farmers Union has in recent weeks insisted that the Federal Agency coordinating the fight itself would take, with the deployment of the Sanitary Fund.

Today there was a meeting place, where, in addition to the sector organizations, the Federal Public Health and the Agency, representatives of the Cabinet-Ducarme and Flanders were present. The mean thing was to discuss a number of measures together with the industry to address the virus in a centrally organized manner and to curb.

For this, the necessary deployment of the Sanitary Fund should be considered. Within the meeting there was agreement found to address the problem and the Agency will undertake the coordination of the control and eradication of the arrangements made. The measures, including related fees, in the coming days within the AFSCA now developed and submitted to the competent minister. Once these are finalized we will communicate.

Minister Ducarme working on a decision t where control measures are strengthened with the deployment of the Sanitary Fund. Hopefully this decision quickly in order to start the fight. The industry is asked not to weaken the biosecurity measures and be vigilant.

 And from May 7th:

Farmers Union requires coordinated fight with compensation Sanitary Fund

Farmers Union wants the Minister FASFC gives the order to coordinate the fight to take the virus itself and demands that the affected companies are reimbursed with funds from the Sanitary Fund.
7 mei 2019

Wouter Wytynck, advisor Animal production, Research Farmers Union

In recent weeks several poultry farms in East and West Flanders and one in Hengouwen affected by low pathogenic avian influenza virus of type H3. It is mainly about laying and breeding companies, but also some companies kalkoenen- and broilers tested positive for the virus.

Meanwhile, the number of cases continues to rise and the counter at 28. In addition, a number of companies under suspicion. Most companies currently are fairly close together, but the zone is expanding further.

Research has shown that pathogenicity is at 0.13, which means that the H3 virus for as much havoc it still provides low pathogenic. Remarkably, the H3 virus passes very mild on farms with young animals, what to expect from a low pathogenic virus, but creates serious problems in chickens in production.

Furthermore, it is now clear that the wind is a key vector, creating a sense of powerlessness and poultry, near a fireplace, or anxiously awaiting their chickens will also be affected. It is also true that some infections can be explained through contacts. It is important to keep the focus on biosecurity.

Despite the demand of the industry to do so, there are no measures in accordance with the regulations to date imposed by the Federal Agency. From a legal perspective, the law is very clear when action should be taken. This is the case:

• H5 and H7 strains, regardless of whether they are LPAI or HPAI;
• All strains of HPAI character, that in technical terms, a pathogenicity index of over 1.2.

Problem today is that there is no coordination of control and that the companies are not removed, so the virus remains present in large numbers and further spread. Alternatively for companies that need to be overcome than there is currently no compensation from the Sanitary Fund provided. That makes it difficult to get the virus under control and the problem is increasing.

Farmers Union also wants the Minister FASFC gives the order to coordinate the fight to take the virus itself and demands that the affected companies are reimbursed with funds from the Sanitary Fund. There are also different contacts before today laid. Given the rapid spread of the virus Agrofront also asked in a letter to Minister Ducarme to see the demand to fight with urgency. The damage and the cost of control is indeed the day higher.

The notion that avian flu viruses can be spread via the wind is not a new one, but only in recent years have we seen evidence to support the theory (see 2018's Frontiers: Two Studies On The Epidemiology of Avian Influenza Viruses).

Poultry farms, and even live markets, can produce a great deal of potentially contaminated `dust', made up of desiccated poultry droppings, feathers, and other debris. Large poultry houses have exhaust fans that control the temperature, but can also help aerosolize virus particles.

Going back even further, in December of 2012  (see Barnstorming Avian Flu Viruses?) we looked at a study in the Journal of Infectious Diseases called Genetic data provide evidence for wind-mediated transmission of highly pathogenic avian influenza that found patterns that suggested farm-to-farm spread of the 2003 H7N7 in the Netherlands due to the prevailing wind.

Another study of the same outbreak, Modelling the Wind-Borne Spread of Highly Pathogenic Avian Influenza Virus between Farms (PloS One 2012), found that wind borne transmission could have accounted for up to 24% of the transmission over distances up to 25 km. 

In Asia we've seen numerous instances where the `dust’ from chicken farms or live markets has been strongly suspected of having spread bird flu – at least for a distance of several hundred yards.

For some human bird flu cases in Indonesia and China, the only known exposure has been listed as living near, or simply walking past, a poultry farm or live market. 

While the wind spread of H3N1 in Belgium appears to based more on speculation than scientific proof, it is a plausible mechanism when the winds, temperature, and humidity are favorable. 

For even more on this unique natural vector - with ramifications that extend far beyond avian flu - you may wish to revisit my blog from early 2018 called It's Raining Viruses.

While it is important to track down how this virus is being spread from farm-to-farm, the bigger question is why a previously benign LPAI H3N1 virus has suddenly become deadly in poultry, and what that might mean for other potential hosts.

Stay tuned.