Naslov
Extremely high Leptospira carriage rate influenced by climate conditions

Autori
Štritof Majetić, Zrinka ; Habuš, Josipa ; Mojčec Perko, Vesna ; Vucelja, Marko ; Margaletić, Josip ; Starešina, Vilim ; Milas, Zoran ; Perharić, Matko ; Turk, Nenad

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Skup
2nd ELS meeting on leptospirosis and other rodent borne haemorrhagic fevers

Mjesto i datum
Amsterdam, Nizozemska, 16.04.2015

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
leptospiroza ; glodavci ; kliconoštvo ; klima
(leptospira ; rodents ; carriage rate ; climate)

Sažetak
Leptospirosis is classified as a typical disease of the natural foci, meaning that leptospires are maintained in nature by a large variety of animal hosts with rodents as the most important reservoirs. It is well known that a combination of various climatic, hydrologic and edaphic factors have a major impact on incidence of leptospirosis in humans and animals. However, the exact mechanisms and the contribution of individual factors are not fully understood. In order to dissect the impact of various factors, we undertook a systematic study of mouse like rodents in a limited area known as endemic focus of leptospirosis. Investigated site, Lipovljani area, is located in the close proximity of river Sava and has been systematically investigated for the last four years. Average relative abundance of rodents was calculated based on the number of animals trapped in trap snaps positioned along transect lines. Rodents were aseptically dissected and kidney tissue from each animal was cultured in Korthoff's medium and sampled for DNA extraction. Average relative abundance for the period from 2011 to 2013 ranged from 0.1 % to 16.5% with renal carriage rates ranging from 8% to 28%. However, in September 2014, during the regular annual survey, an extremely high relative abundance of rodent population (55.5%) as well as Leptospira isolation rate of 55.1% (38/69) were detected. Due to relatively high percentage of contaminated kidney cultures, additional PCR testing was performed on kidneys of related animals and additional 11 positive animals were detected. In total, extremely high carriage rate of 71% (49/69) was determined. To our knowledge, this is the highest rodent infection rate ever recorded in Europe. According to percentile ranges and classification ratings, climate conditions in 2014 in the whole Croatia, including Lipovljani area, have been described as extremely warm and extremely humid with precipitation amounts higher than average in the last 30 years. High precipitation amounts and saturation of soil with water as a consequence, resulted in severe flooding in some parts of Croatia, especially in surroundings of big rivers. Climate specificities in 2014 that were recorded throughout the year obviously had a major influence on relative abundance of rodents by increasing food availability and lowering mortality during winter period. High abundance of rodents inevitably resulted in more direct and indirect contacts between animals, which, together with prolonged survival of Leptospira in environment due to favorable climate conditions, increased possibility of infection within rodent population. We can conclude that extremely high Leptospira carriage rate recorded in this study was a consequence of climate conditions affecting many important ecological factors that synergistically lead to increase in Leptospira carriage rate in reservoirs.

Izvorni jezik
Engleski

Znanstvena područja
Javno zdravstvo i zdravstvena zaštita, Veterinarska medicina

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