Grigorios Markakis’s research while affiliated with Aristotle University of Thessaloniki and other places

Haemosporidians, a group of vector-borne parasites that parasitize the blood cells and internal organs of various animal species, are reported to cause severe pathology in raptors. Species belonging to the genera Plasmodium, Haemoproteus and Leucocytozoon are the ones of greatest wildlife importance. The common buzzard (Buteo buteo) and the Eurasian sparrowhawk (Accipiter nisus) are the most numerous raptor species in Europe. Reliable data is lacking for many raptor species in Greece. The aim of this study was to assess, for the first time, the prevalence and geographical distribution of haemosporidian infection (mainly Leucocytozoon and Plasmodium) in these two avian species in Greece, in correlation with the risk factors of age and sex. In total, 62 common buzzards and 26 Eurasian sparrowhawks were included in this study, all being admitted for treatment at a Greek Wildlife Rehabilitation Center. Blood samples were collected and microscopical analysis was performed after staining blood smears with Giemsa. DNA was extracted from each sample and a fraction of the mitochondrial cytochrome b gene was amplified by a nested PCR protocol. All positive samples were subjected to sequencing. Total prevalence of haemosporidian infection by morphological and molecular examination was 59% and 73.9%, respectively. Binary logistic regression was carried out. The most prevalent infection was by Leucocytozoon spp. Most of the samples had mixed infections. The isolated genetic lineages of Leucocytozoon spp. were BUBT2, BUBT3, MILVUS01, ACNI1, BUBO01 and MILANS04. The detected genetic lineages of Plasmodium spp. were TURDUS1, BT7 and DONANA02. A new genetic lineage, BUTBUT17, was also identified.

Dirofilaria immitis is a ubiquitous nematode parasite with zoonotic potential, transmitted by mosquitoes, that causes heartworm disease in various animal species. Dogs are the parasite’s typical final host, and wild carnivores represent the parasite’s reservoir in nature. Studies on D. immitis infections in wild animals are essential to assess infection pressure for domestic animals, and until now, there has been only one infection case reported in a European badger (Meles meles). The current report describes the first two European badger cases with cardiovascular dirofilariosis in Greece. Two adult male badgers were rescued in Heraklion and Chania, Crete Island, and admitted to “ANIMA -Wildlife Rehabilitation Centre” in Athens. The detailed clinical examination revealed that the first badger suffered from severe broncho-pneumonitis while the second one displayed clinical signs associated with severe brain trauma. Blood samples were taken for haematology and biochemistry analyses during their short hospitalisation period. In addition, different routine diagnostic tests were carried out, including heartworm antigen testing (ELISA) and the modified Knott’s test for microfilariae. Both badgers were positive in both tests. The animals died a few hours after their admission and the detailed necropsies followed, revealed the presence of three parasites in each animal’s right heart, morphologically identified as adults of D. immitis. These findings add the European badger in the list of additional potential reservoir hosts for D. immitis and highlight the potential role of wildlife for companion animals and human health.