From the Netherland’s Ministry of Economic Affairs we get the following (Google Translated) announcements regarding a recent outbreak of bird flu – likely LPAI H7 – on a poultry farm in Lochem (see map above).
Newsflash | 12/03/2013
Lochem is a poultry farm with 85,000 hens bird flu (avian influenza, AI) was adopted. This company has 3 stables with outdoor access. It is probably the mild H7 variant.
Because a low pathogenic (mild) H7 variant can mutate into a highly pathogenic (highly contagious and lethal to chickens) variant, the company both at low and high pathogenic variant are removed. This is based on European rules. The depopulation is by the Dutch Food and Consumer Product Safety Authority (nVWA).
From Tuesday, March 12, 2013 at 16:00 applies in an area of over 1 kilometer around the holding in Lochem one for the transport of poultry, eggs, poultry manure and used bedding. Within the area there are 3 other poultry. The animals on these companies in the coming days will be checked for bird flu.
The coming period will apply to those companies also cover requirement. That means all poultry on those companies should be kept inside. This obligation applies only to commercial poultry.
There are two broad categories of avian influenza; LPAI (Low Pathogenic Avian Influenza) and HPAI (Highly Pathogenic Avian Influenza).
- LPAI viruses are quite common in wild birds, cause little illness, and only rarely death. They are not considered to be a serious health to public health. The concern is (particularly with H5 & H7 strains) that LPAI viruses have the potential to mutate into HPAI strains.
- HPAI viruses are more dangerous, can produce high morbidity and mortality in wild birds and poultry, and can sometimes infect humans with serious result. The type of bird flu scientists have been watching closely for the past decade has been HPAI H5N1 (and to a lesser extent HPAI H7s & H9s).
Before the middle of the last decade, there was no uniform requirement to report or track LPAI infections. That changed in 2006 when the OIE made reporting of LPAI H5 & H7 viruses mandatory.
And while it doesn’t appear to happen often, we’ve seen sporadic human infection from (LP & HP) H7 strains of avian influenza over the years.
Ten years ago, the largest known cluster (89 confirmed, 1 fatality) was reported from the Netherlands. In that case, the viral culprit was H7N7.
More recently, in Mexico we saw two mild human cases last summer (see see MMWR: Mild H7N3 Infections In Two Poultry Workers - Jalisco, Mexico).
For now, these LPAI viruses are primarily a threat to the poultry industry, and to a far lesser extent, people working in direct contact with infected fowl.
Although global surveillance and reporting on novel avian viruses in humans is spotty at best, some known H7 cases include:
Chart lifted and edited from CIDRAP’s excellent overview Avian Influenza (Bird Flu): Implications for Human Disease showing known H7 avian flu infections in humans over the two decades.
Thus far, this outbreak is reportedly limited to one poultry farm. We’ll have to wait to see if testing reveals that this virus has managed to spread beyond this one location.