Once imported, it is likely that the disease could become established because of the presence of local potential tick Trichostatin A vectors [5, 41]. In order to prevent this pathogen from spreading into the USA, a screening

test with high sensitivity and specificity is needed prior to the animal importation. In this respect, the 17 DNA samples from A. americanum harboring DNA from Ehrlichia species that are enzootic to the USA were found to be negative in LAMP. Considering that the detection limits of the PCR assay used for the detection of Ehrlichia species in A. americanum were 10 copies per reaction [42], which is comparable to those of LAMP assays, these samples were LAMP-negative not because the DNA concentrations were below the detection levels but probably because there were no cross find more reactions due to sequence mismatches or deletions in the targeted regions. Conclusions The LAMP assays developed in this study allow rapid, sensitive, and specific detection of E. ruminantium. Although LAMP reactions were inhibited in the presence of extracts from blood and ticks, the diagnostic sensitivity of LAMP was higher than that of conventional PCR, when tested with field-collected ticks. Since LAMP requires minimal time and equipment to perform, this technique can potentially

be used in resource-poor settings where heartwater is endemic. The PS-341 order lack of cross-reactivity with closely related Ehrlichia species enhances its utility for active screening in areas under threat of the introduction of the disease. Methods Rickettsial bacteria E. ruminantium isolates used in this study were: Ball 3, Burkina Faso, Crystal Springs, Gardel, attenuated Gardel, Ifé Nigeria, Kerr Seringe, Kiswani, Kwanyanga, Lutale, Pokoase 471, Sankat 430, Montelukast Sodium São Tomé, Senegal, attenuated Senegal, Um Banein,

Welgevonden, and Zeerust. Attenuated isolates of Gardel and Senegal were obtained by serial passages in mammalian cells as previously described [43]. All were cultured in bovine aorta endothelial (BAE) cells as described previously [44] and subjected to DNA extraction. Cultures of closely related rickettsia, including E. canis, E. chaffeensis, A. centrale, A. marginale, and A. phagocytophilum, were also used for LAMP specificity testing. Field samples From July 2008 to January 2009, adult A. variegatum ticks were collected from indigenous cattle in seven districts in Uganda: Amuria, Butaleja, Dokolo, Kaberamaido, Pallisa, Soroti, and Tororo. Ticks were pooled and stored in sealed plastic bags containing silica gel until DNA extraction. Twenty ticks from each site were randomly selected, and a total of 140 (96 males and 44 females) samples were used in the present study. From July 2008 to May 2009, blood samples were collected from clinically healthy cattle or goats in four different sites in sub-Saharan countries.