Concurrent Infections with Vector-Borne Pathogens Associated with Fatal Hemolytic Anemia in a Cattle Herd in Switzerland

Abstract

Bovine anaplasmosis is a vector-borne disease that results in substantial economic losses in other parts of the world but so far not in northern Europe. In August 2002, a fatal disease outbreak was reported in a large dairy herd in the Swiss canton of Grisons. Diseased animals experienced fever, anorexia, agalactia, and depression. Anemia, ectoparasite infestation, and, occasionally, hemoglobinuria were observed. To determine the roles of vector-borne pathogens and to characterize the disease, blood samples were collected from all 286 animals: 50% of the cows were anemic. Upon microscopic examination of red blood cells, Anaplasma marginale inclusion bodies were found in 47% of the cows. The infection was confirmed serologically and by molecular methods. Interestingly, we also found evidence of infections with Anaplasma phagocytophilum, large Babesia and Theileria spp., and Mycoplasma wenyonii. The last two species had not previously been described in Switzerland. Anemia was significantly associated with the presence of the infectious agents detected, with the exception of A. phagocytophilum. Remarkably, concurrent infections with up to five infectious vector-borne agents were detected in 90% of the ill animals tested by PCR. We concluded that A. marginale was the major cause of the hemolytic anemia, while coinfections with other agents exacerbated the disease. This was the first severe disease outbreak associated with concurrent infections with vector-borne pathogens in alpine Switzerland; it was presumably curtailed by culling of the entire herd. It remains to be seen whether similar disease outbreaks will have to be anticipated in northern Europe in the future.

Prevalence of Hemoplasma Infection among Cattle in the Western Part of Japan

“…The hemoplasma-infected cattle in the present study did not exhibit clinical signs such as anemia attributable to hemoplasmosis, though hemoplasma infections in cattle were first recognized in Swiss dairy cows with hemolytic anemia [3]. In our study, no significant association was found between the infection status and anemic syndromes.…”

“…Although M. wenyonii has been shown to exhibit worldwide geographical distribution, 'C. M. haemobos' has been solely reported from Switzerland, China, Germany and Japan [2,3,8,9]. Both hemoplasma species are causative of infectious anemia in cattle to some extent and have been demonstrated in Hokkaido and Tohoku regions of this country.…”

Molecular and serological evidence of Anaplasma phagocytophilum infection of farm animals in the Black Sea Region of Turkey

“…The rate of infection has been reported to be variable between countries and it may vary considerably even between neighbouring farms (Stuen et al, 2002). The prevalence of infection with A. phagocytophilum worldwide has been reported to range from 0.51% to 80% de la Fuente et al, 2005b;Amusategui et al, 2006) in sheep and from 3.07% to 26% in cattle (Hofmann-Lehmann et al, 2004;Magnarelli et al, 2004;de la Fuente et al, 2005b;Amusategui et al, 2006).…”

Molecular detection and occurrence of 'Candidatus Mycoplasma haemobos' in dairy cattle of Southern Brazil

“…'Candidatus Mycoplasma haemobos' has been reported using molecular methods such as polymerase chain reaction (PCR) and sequencing techniques in cattle from Switzerland, Germany, China, and Japan (HOFMANN-LEHMANN et al, 2004;TAGAWA et al, 2008;SU et al, 2010;HOELZLE et al, 2011). However, to the author's knowledge, no molecular detection has been reported to date in the Americas.…”