Qualitative risk assessment for the endemisation of Dirofilaria repens in the state of Brandenburg (Germany) based on temperature-dependent vector competence

Climate change with an increase in average temperature may be responsible for propagation of temperature-dependent vectors and/or vector-associated pathogens in regions that were previously not endemic. The analysis of climate data of Brandenburg state (Germany) had showed that the extrinsic development of Dirofilaria repens, the causative agent of canine subcutaneous dirofilariosis, was possible from the years 2001 to 2012. This finding, associated to the movement of infected dogs and their relocation from endemic European areas to Germany makes possible a rapid endemization of the infection and highlight the risk for human health, being D. repens a frequent cause of zoonotic infections

Climate suitability for the transmission of Dirofilaria immitis and D. repens in Germany

Recently concerns are increasing that dirofilarial nematodes may spread from endemic areas in southern, eastern and central Europe to countries in northern regions of Europe. The increasing number of autochthonous cases of canine Dirofilaria repens infections in Germany indicates that worms of this genus may invade new areas, and climate change may be a key factor in this scenario. Thus analysis of long term development of regional temperature is a pivotal factor in risk analysis related to transmission of these worms. Such information is important for suggestions of counteracting strategies, such as definition of periods of increased transmission risk and, consequently, time slots most suited for preventative measures. In this study, mean daily temperature data from 34 geographical clustered weather stations representing all parts of Germany were analyzed. It is concluded that the increasing trend for average daily temperatures observed in the period from 1984 to 2013 has led to climatic conditions that allow the completion of dirofilarial life cycles in large parts of Germany between May and October. Autochthonous infection with D. repens is already established in some regions and targeted diagnosis and medical prophylaxis is advisable for dogs assumedly exposed during risk of transmission periods. It appears likely that global warming will support further spread of D. repens. Furthermore for the population of dogs the spread of the more pathogenic species D. immitis in hitherto non-endemic Germany is a potential risk if mean temperatures rise to a level suitable for parasite development in the abundant vector mosquitoes during the warmer seasons

Prevalence of and risk factors for feline hyperthyroidism in South Africa

Poster presented at the University of Pretoria, Faculty of Veterinary Science Faculty Day, August 25, 2016, Pretoria, South Africa.Feline hyperthyroidism is a disease of middle-aged to older cats that has shown a marked increase in worldwide incidence within the last three decades as well as a marked geographic variation in prevalence. The exact pathogenesis of the disease still remains obscure and despite a plethora of epidemiological studies, clear risk factors have not been identified. The purpose of this study was to determine the prevalence of feline hyperthyroidism in South Africa and to identify potential risk factors. Serum total thyroxine (tT4) and thyroid stimulating hormone (cTSH) were measured in 302 cats aged 9 years and older that were presented at various veterinary clinics. In a few cats, serum free thyroxine (fT4) was also measured. At the time of blood sampling a questionnaire was completed regarding vaccination history, internal and external parasite control, diet and environment. The prevalence of hyperthyroidism (tT4> 50nmol/L or tT4 between 30-50 nmol/L with cTSH 50pmol/L) within this population was 7.0% with no significant difference in prevalence between healthy (5.1%) and sick (8.2%) cats. Cats ≥ 12years of age (OR= 4.3, p= 0.02) and cats with canned food in their diet (OR= 2.1, p= 0.1) were more likely to be diagnosed with hyperthyroidism. No significant relationship between vaccinations, parasite control or indoor environment and hyperthyroidism was observed. Hyperthyroid cats were more likely to present with weight loss (OR= 3.2, p= 0.01) and with a heart rate ≥ 200bpm (OR= 5, p= 0.01) than cats without the disease.The prevalence of feline hyperthyroidism in South Africa appears to be similar to that in cats in Japan and Portugal but less than that in cats in the UK and Germany. Risk factors for hyperthyroidism, previously found in other studies, specifically older age and eating canned food was present in this study population.ab201