Abstract. Rickettsioses caused by Rickettsia felis are an emergent global threat. Historically, the northern region of the province of Caldas in Colombia has reported murine typhus cases, and recently, serological studies confirmed high seroprevalence for both R. felis and R. typhi. In the present study, fleas from seven municipalities were collected from dogs, cats, and mice. DNA was extracted and amplified by polymerase chain reaction (PCR) to identify gltA, ompB, and 17kD genes. Positive samples were sequenced to identify the species of Rickettsia. Of 1,341 fleas, Ctenocephalides felis was the most prevalent (76.7%). Positive PCR results in the three genes were evidenced in C. felis (minimum infection rates; 5.3%), C. canis (9.2%), and Pulex irritans (10.0%). Basic Local Alignment Search Tool (BLAST) analyses of sequences showed high identity values ( 98%) with R. felis, and all were highly related by phylogenetic analyses. This work shows the first detection of R. felis in fleas collected from animals in Colombia.

Rickettsia typhi and R. felis are the etiological agents of murine typhus and flea-borne spotted fever, respectively. Both are emerging acute febrile zoonotic diseases for which fleas are vectors; they also have similar clinical characteristics and global distribution. In 2005, we identified the circulation of murine typhus in 6 towns within the mountainous coffee-growing area north of Caldas, Colombia. We now report the specific seroprevalence against R. typhi and R. felis, and associated risk factors in 7 towns of this province. The combined seroprevalence against the 2 flea-borne rickettsioses is the highest yet reported in the literature: 71.7% (17.8% for R. felis, 25.2% for R. typhi, and 28.7% for both). We also report a prospective analysis of 26 patients with a febrile illness compatible with rickettsioses, including murine typhus; 9 of these patients had a rickettsiosis. This supports our sero-epidemiological results and highlights the diagnostic complexity of febrile syndromes in this region.

Background: Bacteria from the genus Rickettsia are causative agents of arthropod-borne zoonotic diseases including spotted fevers as well as epidemic and endemic typhus. Different species of Fleas could act as reservoir and vectors of two pathogenic Rickettsia species, R. typhi and R. felis. A considerable number of cases of flea-borne typhus have been reported in Caldas State from the past years and recently we have confirmed 46% and 50% of seroprevalence for R. typhi and R. felis, respectively and two clinical infections with the latter. Until now, there are no reports of vectors of these Rickettsia species in this region. The aim of this work was identify by molecular techniques Rickettsia species in fleas collected in seven municipalities from Caldas State, Colombia.Methods: A total of 1341 fleas were collected from dogs, cats, rats and mice, between 2010 and 2011 from seven municipalities in the north region of Caldas State. All specimens were identified by taxonomy keys and conserved in ethanol for processing. Pools of these fleas were constituted by origin, host and flea species, and submitted to DNA extraction with a commercial kit. All samples were initially screened for gltA gene by PCR with the primers CS-78/CS-323 and positive samples were further analysed for ompB and htrA (17 kD) genes with the pair of primers 120-M59/120-807 and 17kD1/17kD2, respectively.Results: From the 1341 fleas collected, Ctenocephalides felis were the most common species in six Municipalities (76.7%). Other species obtained were C. canis, Pulex irritans and Xenopsylla cheopis. Neira was the municipality with the highest proportion of fleas with 395 specimens (29.5%). From these samples, 182 pools were constituted and from these, 124 were positive for gltA (68%), 104 for ompB (57%), 91 for htrA and 79 for the three genes (43%). Conclusion:These results confirm the high circulation of bacteria from the genus Rickettsia in fleas collected principally in dogs and cats from municipalities with confirmed clinical cases of Fleaborne Rickettsiosis. PCR products are in process of sequencing for further species identification.

Gastroparesis is a disorder characterized by symptoms and evidence of delayed gastric emptying (GE) in the absence of mechanical obstruction. Scintigraphy has been considered a "gold standard" for measuring Gastric Emptying Time (GET) and retention percentage of radio-labeled food, after four hours of ingestion. To obtain the images, it is recommended, worldwide, the use of the Tougas diet (255kcal) as a standard meal. The objective of this study was to compare the GET and the percentage of retention in the time of 4 h, obtained by scintigraphy using the Tougas diet (255 kcal) and the proposed diet (319 kcal). Thirty patients, both genders, aged 23 to 76 years,  were selected, they presenting clinical symptoms suggestive of gastroparesis. These parameters were measured for the same patient, but in different days. The results showed that the diet fat content used to obtain EG of solid foods by scintigraphy did not influence the retention percentage results after 4 hours of ingestion of the radiolabeled food. However, the time of two hours is an important parameter to be observed in the result of this examination. In addition, the data suggest that the proposed diet may be more efficient for the classification of the severity of EG delay in patients with clinical signs suggestive of gastroparesis.