Red mites are a serious challenge to poultry production all over the world

“One Health is a combined effort from several different technical disciplines to improve human, animal and plant health in sustainable eco-systems by using an integrated systemic approach to achieve transnational solutions.”

Wim van der Poel (Central Veterinary Institute, NL) emphasised that interdisciplinary collaboration across technical fields and a systemic approach are required to overcome the problems of red mites, as they affect birds, people and the environment alike.

Cristian Magdas (University of Cluj-Napoca, Romania) conducts research in Romania, which has almost 35 million layer hens. 25% of the hens are kept in private chicken yards with up to 100 hens. Of them, 80–95% have red mites. Inappropriate treatment methods, especially in small private chicken yards, have led to a situation where red mites are resistant to pesticides. One of the biggest concerns in Romania is the use of illegal substances, leading to residue in eggs and meat from these small private chicken yards.

Olivier Sparagano (Coventry University, UK) reviewed a presentation on behalf of David George (Northumbria University, UK), who had to cancel. The focus was on the increasing number of registered red-mite attacks in humans and the need to work together with dermatologists to counteract the under-diagnosis and faulty diagnosing of dermanyssosis. As red mites are suspected of being able to transfer Lyme disease (borrelliosis), Bartonella bacteria and Babesia (a protozo which infects red blood cells), action should be taken to determine the extent to which red mites are a threat to human health.

Correct inspection and monitoring are important parts of conducting research into and controlling red mites. Jutta Berk (Friedrich Loeffer Institute, Germany) presented research results to show that modified mite traps (a plastic tube lined with corrugated cardboard) are useful for determining the presence of mites in laying houses, and an important part of effective mite control.

Developments in DNA-based biotechnology have resulted in fantastic possibilities of improving one’s insight into the behavioural patterns of both red mites and other organisms in poultry housing, which is crucial in light of currently changing global conditions.

Considering the genetic structure as a source for designating DNA markers, this topic relates to the entire methodology and links together all the discussion topics on red mites. DNA markers can provide deeper insight into red-mite epidemiology, as well as better prevention and control methods and can also contribute to identifying possible new control methods (e.g. development of vaccines, managing resistance), not least from a One Health perspective. The value of knowing of the genetic structure in epidemiological studies is effectively underpinned by Øivind Øines (Department of Veterinary Medicine, Oslo, Norway), whose research has shown that the red-mite population found in laying hens in Norway does not appear to have any connection to mites found in wild birds, and that their proliferation is thus quite limited.

The need for genetic studies in other areas as well was emphasised by Danijela Horvatek (University of Zagreb, Croatia), who summarised the research into the role played by red mites as vectors. The need was also emphasised by Jan Chirico (Swedish Institute of Veterinary Medicine) who described the new opportunities for monitoring and controlling various types of arthropods using molecular tools (barcoding/metabarcoding).

The practical application of such new tools at eco-system level in various flocks was demonstrated in a presentation by Monica Young (University of Guelph, Canada), who described why and how genetic barcoding works. For example, by quickly and efficiently characterising micro-organisms living in bedding, it is possible to identify mites and collections of micro-organisms that have a restricting effect on red mites, or other types of mites (such as the northern fowl mite, Ornithonyssus sylviarum), and it is also possible to prove epidemiological patterns for mite-transmitted bacterial or viral illnesses.

The knowledge inherent in red-mite morphology, biology, life cycle, population dynamic and behaviour is crucial information for improving our general understanding of Dermanyssus gallinae and its proliferation on poultry farms. The need to generate this knowledge is directly related to the other themes mentioned here, and the information is essential for determining a shared strategy for charting or monitoring red mites in a wider context. Antonella Di Palma (University of Foggia, Italy) explained how the red mite evolved into a parasite. Her studies of things like the mite’s mouth parts have contributed to an understanding of the mite’s (genetically based) morphological strategy in its attack on host animals.

Lionel Zenner (VetAgro Sup Lyon, France) presented an overview of the red mite’s life cycle, biology and population dynamic and emphasised how this information could be used in model calculations, which makes it possible to predict the effector clean-up or of chemical treatment against mites and is therefore of overarching importance to controlling red mites.

This first COST Action FA1404 conference provided information on much of the research being conducted into red mites in Europe and other countries and the possibility of establishing contact between researchers wishing to collaborate and become members of COST Action FA1404. This is essential as the COST group must open up new lifelines in order to be able to continue to pursue its goals and meet the needs of the poultry industry. It was emphasised at the conference that COST Actions support young researchers by offering short term scientific missions (STSM). In so doing, an effort is made to boost existing networks and establish new collaboration between COST countries, as well as training stays and workshops. STSMs can be applied for by researchers up to eight years after completing their PhD studies.

The first conference could be carried out based on financial support from local institutions (Order of Veterinary Surgeons, Banca del Monte Foundation) and businesses (APPI, Olmix, Bayer, Elanco, Zoochimica and Levanchimica), which are interested in supporting research into sustainable control of this poultry pest.