Clinical manifestations and diagnostic approaches in cases of canine leishmaniasis in Bulgaria.

Leishmaniasis, a parasitic disease found in many parts of southern Europe, is transmitted in both humans and canines through the bite of phlebotomine sandflies, and can present in a variety of ways, such as cutaneous, mucocutaneous, diffuse, and visceral. In Bulgaria there are endemic areas of canine leishmaniasis, with sporadic cases in humans. However, no detailed studies of the animal population and vectors have been performed. Here we describe a few clinical cases of canine visceral leishmaniasis in two districts in western Bulgaria: one endemic and one without previously detected cases in humans or dogs. Diagnosis was confirmed serologically and molecularly using both real time and conventional PCR. Specific anti-leishmanial antibodies were confirmed in three of the cases via ELISA, with 50% of them returning extremely high values. In the majority of the cases DNA fragments were detected in the skin or lymph node aspirate but not in the blood. This paper highlights the need for further studies updating the current knowledge on the epidemiology, diagnosis, and control of visceral leishmaniasis in the reservoir host population.

Detection of Leishmania infantum Antibodies in Stray Dogs from Nonendemic Areas in Bulgaria.

Background: Leishmaniasis is a zoonotic protozoan infection which is endemic in parts of Europe. Dogs are commonly affected by Leishmania infantum and are regarded as the main reservoir for humans' infection. Sporadic human cases are reported annually, mainly from the endemic south part of Bulgaria. However, no recent data on canine leishmaniasis geographical distribution in Bulgaria have been published. The aim of this study was to investigate the current seroprevalence rate of L. infantum in stray dogs from areas where this infection was not previously reported. Results: The estimated overall seroprevalence rate was 8.3% (95% confidence interval [CI]: 2.6-14.0) with no significant difference between the two examined districts [χ2 (1, N = 90) = 0.32, p = 0.69]. In Sofia, the seropositivity was 7.2% (95% CI: 0.9-13.5) and in Sofia (stolitsa) 11.0% (95% CI: 0-23.0). No association between sex and serological status [χ2 (1, N = 90) = 1.83, p = 0.27] and age and seropositivity [χ2 (2, N = 90) = 1.98, p = 0.52] was detected. High levels of antibodies (fourfold increase from the assay's cut-off) were observed in half of the positive dogs.

Pathologic Evaluation of Influenza A H5N8 Infection Outbreaks in Mule Ducks in Bulgaria.

This article outlines pathomorphologic findings of a study involving commercial mule ducks with confirmed influenza A H5N8 infections after a series of outbreaks in Bulgaria. Examinations were carried out after performing necropsy on dead birds from three different age groups (up to 15, 20 to 30, and 40+ days of age) fattened on different farms. Among birds of all ages, gross lesions were present as lesions affecting the heart. Histologically, the myocardium exhibited severe intermyofibrillar edema, moderate to massive hemorrhages, and degenerative changes. All lesions resulted in single or multiple and small to massive myocardial infarctions. Other affected organs included the brain, lungs, liver, spleen, and pancreas. Nonpurulent lymphocytic encephalitis was found postmortem in ducks that had shown prior clinical nervous signs. Among ducks of all ages, a viral antigen in the cardiomyocytes and the epithelium of air capillaries was found through immunohistochemical detection methods. The results of the present study allowed us to conclude that the highly pathogenic avian influenza A H5N8 viral infection may manifest itself as a systemic illness in commercial mule ducks with septicemic lesions, resulting in high morbidity and mortality rates of up to 100%. Pathomorphologic lesions were somewhat different from those previously reported in wild waterfowl.

Evaluación patológica de brotes de infección por influenza A H5N8 en patos mula en Bulgaria. Este artículo describe los hallazgos patomorfológicos de un estudio que involucró patos mula comerciales con infecciones confirmadas de influenza A H5N8 después de una serie de brotes en Bulgaria. Los exámenes se llevaron a cabo después de realizar la necropsia en aves muertas de tres grupos de edad diferentes (hasta 15 días, de 20 a 30 días y más de 40 días de edad) engordadas en diferentes granjas. Entre las aves de todas las edades, las lesiones macroscópicas estaban presentes como lesiones afectando el corazón. Histológicamente, el miocardio exhibió edema intermyofibrillar severo, hemorragias moderadas a masivas y cambios degenerativos. Todas las lesiones resultaron en infartos de miocardio simples o múltiples y de pequeños a masivos. Otros órganos afectados incluyeron el cerebro, los pulmones, el hígado, el bazo y el páncreas. Se encontró encefalitis linfocítica no supurativa se encontró post mortem en patos que habían mostrado signos nerviosos clínicos previos. Entre los patos de todas las edades, se encontró un antígeno viral en los cardiomiocitos y el epitelio de los capilares aéreos a través de métodos de detección inmunohistoquímica. Los resultados del presente estudio nos permitieron concluir que la infección viral altamente patógena de la influenza aviar H5N8 puede manifestarse como una enfermedad sistémica en patos mulos comerciales con lesiones septicémicas, lo que resulta en altas tasas de morbilidad y mortalidad de hasta el 100%. Las lesiones patomorfológicas fueron algo diferentes de las reportadas previamente en aves acuáticas silvestres.

Pathological Changes in Natural Infection of Pheasants with Highly Pathogenic Avian Influenza A (H5N8) in Bulgaria.

INTRODUCTION: The study of histopathological changes caused by influenza A (H5N8) viral infection in bird species is essential for the understanding of their role in the spread of this highly infectious virus. However, there are few such studies under natural conditions in minor gallinaceous species. This article describes the pathomorphological findings in Colchis pheasants infected naturally with H5N8 during an epizootic outbreak in Bulgaria. MATERIAL AND METHODS: Samples of internal organs of 10 carcasses were collected for histopathological and immunohistochemical evaluation, virus isolation and identification, and nucleic acid detection. RESULTS: Consistent macroscopic findings were lesions affecting the intestine, heart, lung, and pancreas. Congestion and mononuclear infiltrate were common findings in the small intestine, as were necrosis and lymphoid clusters in the lamina propria of the caeca. Congestion with small focal necrosis and gliosis with multifocal nonpurulent encephalitis were observed in the brain. Myocardial interstitial oedema and degenerative necrobiotic processes were also detected. Immunohistological analysis confirmed systemic infection and revealed influenza virus nucleoprotein in all analysed organs. CONCLUSION: Variable necrosis was observed in the brain, liver, trachea, heart, small intestine, and caeca. Viral antigen was commonly found in the brain, heart, lung and trachea. Contact with migrating waterfowls was suspected as a reason for the outbreak.