Bacteria Inside Red Mites Could Be Targeted To Control Poultry Pests

Economic losses inside the European Union caused by the red poultry mite are now running at roughly €130 million or nearly £90 million every year. The mite causes blood spotting on eggs, making them unfit for sale. In severe cases the infested birds can become badly anaemic and fall ill, or get infections caused by bacteria and viruses which can be passed on to people, giving them dangerous illnesses.

"With the recent changes in regulations brought on by new threats like bird 'flu, coupled with a growing and widespread resistance to the chemicals we use to fight poultry mites, called acaricides, we urgently need to develop new approaches to combat these pests", says Dr Olivier Sparagano from Newcastle University, UK.

"If somehow we could develop a method to destabilise the symbiotic bacteria that we have discovered living inside the mites, therefore removing the beneficial effect, we could develop a new control method for the chicken red mite", says Dr Sparagano.

If the scientists are successful then the use of acaricide chemicals could be cut, which in turn would reduce the harmful effect they have on the environment and cut down cases of skin rashes and dermatitis in poultry farmers, smallholders and meat packers. Some traces of acaricides have even been found in eggs intended for human consumption.

"The bacteria are obviously very important to the mites. A new control method based on attacking the symbiotic bacteria inside the mites' bodies would also create economic benefits through higher egg quality and production, and fewer diseases transmitted by these parasitic mites. It would also lead to better welfare for the birds", says Dr Sparagano.

Red poultry mites are a direct threat to economically valuable birds, suspected of passing on diseases like Newcastle Disease. But they have also been shown to be part of a wider chain transmitting diseases to people and other animals such as the food poisoning bacteria Salmonella, and equine encephalitis in horses.

*Dr Sparagano presented the poster 'Endosymbionts of the chicken red mite (Dermanyssus gallinae)'  on 05 September 2007 in the Eukaryotic Microbiology Group session of the 161st Meeting of the Society for General Microbiology at the University of Edinburgh, 03 - 06 September 2007.