Whole-Genome Sequence of Rickettsia parkeri Strain Atlantic Rainforest, Isolated from a Colombian Tick.

Rickettsia parkeri is classified as a member of the alphaproteobacterial microorganisms, genus Rickettsia Here, we report the complete genome sequence of Rickettsia parkeri strain Atlantic Rainforest, which was isolated from an Amblyomma ovale tick collected in the municipality of Necoclí, Colombia.

Wild and domestic animals likely involved in rickettsial endemic zones of Northwestern Colombia.

Between 2006 and 2008, three outbreaks of human rickettsiosis occurred in Northwestern Colombia (municipalities of Necoclí, Los Córdobas and Turbo), with case fatality rates between 27% and 54%. The aim of this study was to determine previous exposure of wild and domestic animals to spotted fever group (SFG) rickettsiae through serological tests, to detect rickettsial evidence in their ectoparasites, and to analyze their possible role in the epidemiology of rickettsial diseases in this zone of the country. A cross-sectional association study was performed from 2010 to 2011. Blood and ectoparasite samples were collected from domestic animals and small mammals. A statistically significant association (p<0.05) between seropositive animals and the study zones was observed. A total of 2937 ticks, 672 fleas and 74 lice were collected and tested in pools by PCR. The minimum infection rate (MIR) of the positive pools was 5% in ticks, 4% in fleas, and 0% in lice. Phylogenetic analyses showed circulation of three 4.Rickettsia species: R. felis in fleas, and R. bellii and Rickettsia sp. strain Atlantic rainforest, both in Amblyomma ovale ticks. In conclusion, this study demonstrated the occurrence of SFG rickettsiae in domestic, synanthropic and wild animals, and suggests the use of equines and canines as good sentinels of infection, in the study zone. We speculate that a transmission cycle exist involving rodents in the areas where these outbreaks have occurred. Tomes' spiny rats (Proechimys semispinosus) and common opossums (Didelphis marsupialis) could be good candidates as amplifier hosts for SFG rickettsiae in enzootic/endemic zones.

Human prevalence of the spotted fever group (SFG) rickettsiae in endemic zones of Northwestern Colombia.

In February 2006, an outbreak of human rickettsiosis occurred in the municipality of Necoclí Colombia, with 35% of lethality. This episode was, followed by two more, one in the municipality of Los Cordobas in 2007 with a 54% of lethality and the other one in the municipality of Turbo in 2008 with 27% of lethality. The aim of this study was to perform serological tests in healthy persons to determine the seroprevalence of antibodies against spotted fever group (SFG) rickettsiae and develop a survey to study some infection risk-related factors. A cross-sectional study was performed in 2011 and 2012. A blood sample and survey of associated factors was performed in healthy persons. A prevalence of 32%-41% was found in healthy people. From the multivariate analysis, we found that people living more than 16 years in these sites had a 79% higher risk of being seropositive and a 46% higher risk when they reported having birds in their houses if the variable of having a horse was included in the model. In conclusion, this study shows endemicity of at least one spotted fever group Rickettsia in the study zone.

Phylogenetic Relationship of Necoclí Virus to Other South American Hantaviruses (Bunyaviridae: Hantavirus).

The results of a previous study suggested that Cherrie's cane rat (Zygodontomys cherriei) is the principal host of Necoclí virus (family Bunyaviridae, genus Hantavirus) in Colombia. Bayesian analyses of complete nucleocapsid protein gene sequences and complete glycoprotein precursor gene sequences in this study confirmed that Necoclí virus is phylogenetically closely related to Maporal virus, which is principally associated with the delicate pygmy rice rat (Oligoryzomys delicatus) in western Venezuela. In pairwise comparisons, nonidentities between the complete amino acid sequence of the nucleocapsid protein of Necoclí virus and the complete amino acid sequences of the nucleocapsid proteins of other hantaviruses were ≥8.7%. Likewise, nonidentities between the complete amino acid sequence of the glycoprotein precursor of Necoclí virus and the complete amino acid sequences of the glycoprotein precursors of other hantaviruses were ≥11.7%. Collectively, the unique association of Necoclí virus with Z. cherriei in Colombia, results of the Bayesian analyses of complete nucleocapsid protein gene sequences and complete glycoprotein precursor gene sequences, and results of the pairwise comparisons of amino acid sequences strongly support the notion that Necoclí virus represents a novel species in the genus Hantavirus. Further work is needed to determine whether Calabazo virus (a hantavirus associated with Z. brevicauda cherriei in Panama) and Necoclí virus are conspecific.

Efectos de la terapia de reemplazo hormonal sobre la función sexual de mujeres con menopausia natural o quirúrgica / Effects of hormone replacement therapy on sexual function of women with natural menopause or surgical

Objetivo: Determinar los efectos de la terapia de reemplazo hormonal sobre la función sexual de mujeres con menopausia natural o quirúrgica, en la consulta de ginecología del Hospital “Dr. Pedro García Clara”; Municipio Lagunillas, Estado Zulia. Métodos: Investigación de tipo comparativa y aplicada, con diseño no experimental, contemporáneo y de campo, que incluyó una muestra de 80 pacientes con diagnóstico de menopausia, dividida en dos grupos de acuerdo a la toma o no de la terapia de reemplazo hormonal y a su vez en dos subgrupos de acuerdo al tipo de menopausia; las cuales fueron evaluadas mediante el índice de función sexual. Resultados: Se encontraron diferencias significativas (P< 0,05) a favor de la terapia de reemplazo hormonal en menopáusicas naturales e histerectomizadas en cuanto al deseo, frecuencia de la excitación, satisfacción y dolor posterior a la penetración; además de encontrarse diferencias altamente significativas en cuanto a la lubricación y a la frecuencia del orgasmo (P< 0,001). Asimismo se determinó una alta prevalencia de disfunción sexual (63,75 %) representando la ausencia de la terapia de reemplazo hormonal un riesgo significativo para disfunción sexual (OR (IC95 %)= 11,94 (3,953-36,081); P= 0,000), mientras que el tipo de menopausia no (OR (IC95 %)= 0,897 (0,360-2,234); P= 0,179). Conclusión: La puntuación total alcanzada en ambos grupos mostró diferencias significativas entre ellos, por lo cual se concluye que la terapia de reemplazo hormonal mostró ser beneficiosa para la función sexual femenina, sin repercusión aparente de la remoción o no del útero.

Objective: To determine the effects of hormone replacement therapy on sexual function in women with natural or surgical menopause at the outpatient clinic of gynecology of the Hospital “Dr. Pedro Garcia Clara”; Municipio Lagunillas, Estado Zulia. Methods: Comparative and applied type research with non-experimental, contemporary and field design, which included a sample of 80 patients diagnosed with menopause, divided into two groups according to whether or not taking hormone replacement therapy and into two subgroups according to type of menopause; measured by the female sexual function index. Results: It’s found significant differences (P <0.05) in favor of hormone replacement therapy in natural menopausal and hysterectomy in terms of desire, frequency of arousal, satisfaction and pain after penetration, in addition to being highly significant differences in terms of lubrication and orgasm frequency (P< 0.001). It also determined a high prevalence of sexual dysfunction (63.75 %) representing the absence of hormone replacement therapy a significant risk for sexual dysfunction (OR (95 %) = 11.94 (3.953 to 36.081), P = 0.000), while not the type of menopause (OR (95 %) = 0.897 (0.360 to 2.234), P = 0.179). Conclusion: The total score achieved in both groups showed significant differences between them, it was concluded that hormone replacement therapy showed to be beneficial for female sexual function, without apparent impact of the removal of the uterus or not.

Infection of Amblyomma ovale by Rickettsia sp. strain Atlantic rainforest, Colombia.

Our goal was to understand rickettsial spotted fevers' circulation in areas of previous outbreaks reported from 2006 to 2008 in Colombia. We herein present molecular identification and isolation of Rickettsia sp. Atlantic rainforest strain from Amblyomma ovale ticks, a strain shown to be pathogenic to humans. Infected ticks were found on dogs and a rodent in Antioquia and Córdoba Provinces. This is the first report of this rickettsia outside Brazil, which expands its known range considerably.

Efecto de la terapia hormonal combinada (drospirenona / 17 β -estradiol) sobre el peso corporal en posmenopáusicas

Objetivo: Comparar los efectos de la terapia hormonal combinada (drospirenona /17 β-estradiol) versus un placebo sobre el peso corporal u otras variables antropométricas en pacientes posmenopáusicas asistidas en la consulta ginecológica del Hospital “Dr. Manuel Noriega Trigo”, Estado Zulia, Venezuela. Métodos: Estudio cuasi-experimental, de casos y controles, aleatorio, a simple ciego, en el cual participaron 120 mujeres posmenopáusicas, divididas en dos grupos para recibir una dosis diaria durante 6 meses de una terapia hormonal combinada (grupo A; drospirenona 2 mg/ 17 β-estradiol 1 mg) o un placebo (grupo B). Se evaluaron tanto el peso corporal como el índice de masa corporal, circunferencia abdominal e índice de cintura cadera, antes y al final del tratamiento. Resultados: Se evidenció que en el grupo que recibió la terapia hormonal hubo una reducción de alrededor de 3 kg en la media del peso corporal luego de 6 meses de tratamiento (79,80±9,35 vs. 76,33±8,36; P< 0,001); asimismo, una reducción significativa en el índice de masa corporal (30,12±2,02 vs. 28,72±1,79; P< 0,001), circunferencia abdominal (120,10±14,73 vs. 110,10±14,00; P< 0,001) y en el índice cintura cadera (0,87±0,04 vs. 0,84±0,07; P< 0,05). En el grupo que recibió un placebo no hubo modificaciones significativas en estas variables. Conclusiones: La terapia hormonal con drospirenona /17 β-estradiol se asoció con una reducción significativa del peso corporal, índice de masa corporal, circunferencia abdominal e índice cintura cadera luego de 6 meses de tratamiento en posmenopáusicas; con pocos o leves efectos adversos.

Objective: To compare the effects of combined hormonal therapy (drospirenone/17 β-estradiol) versus a placebo on body weight and other anthropometric variables in postmenopausal women assisted in the gynecology consultation at the Hospital “Dr. Manuel Noriega Trigo”, in Zulia state, Venezuela. Methods: A quasi-experimental, case control, randomized, single blind study, which involved 120 postmenopausal women, divided into two groups to receive a daily dose for 6 months of combined hormone therapy (group A; drospirenone 2 mg/ 17 β-estradiol) or placebo (group B). We evaluated body weight, body mass index, waist circumference and waist-hip ratio, before and at the end of treatment. Results: We showed that in the group receiving hormonal therapy with drospirenone / 17 β-estradiol was a reduction of about 3 kg in mean body weight after 6 months of treatment (79,80 ± 9,35 vs. 76,33 ± 8,36; P <0,001); and a significant reduction in body mass index (30,12 ± 02,02 vs. 28,72 ± 1,79; P <0,001), abdominal circumference (120,10 ± 14,73 vs. 110,10 ± 14,00; P <0,001) and waist hip (0,87 ± 0,04 vs. 0,84 ± 0,07; P <0;05). In the group receiving a placebo had no significant changes in these variables. Conclusions: Hormonal therapy with drospirenone / 17 β-estradiol was associated with a significant reduction in body weight, body mass index, waist circumference and waist-hip ratio after 6 months of treatment in postmenopausal women, with few or mild side effects.

Caso probable de fiebre manchada ( Rickettsia felis) transmitida por pulgas / Probable case of flea-borne spotted fever ( Rickettsia felis )

Rickettsia felis es el agente etiológico de la fiebre manchada transmitida por pulgas, cuyo principal vector y reservorio es Ctenocephalides felis . Típicamente, la enfermedad se presenta como fiebre aguda asociada a cefalea, astenia, exantema máculo-papular generalizado y, en algunos casos, con escara de inoculación. En los últimos años, R. felis ha venido adquiriendo un papel importante en la etiología del síndrome febril agudo, calificándola como una enfermedad emergente y subdiagnosticada. La inmunofluorescencia indirecta es actualmente el método diagnóstico de referencia. Sin embargo, esta técnica presenta limitaciones relacionadas con la reacción cruzada que existe entre las diferentes especies del género Rickettsia . En el presente reporte se describe el caso de un paciente de 16 años con síndrome febril agudo secundario a infección probable por R. felis .

Rickettsia felis is the etiologic agent of flea-borne spotted fever, with Ctenocephalides felis as its main vector and reservoir. Typically, the disease presents as acute fever associated with headache, asthenia, generalized maculo-papular rash, and in some cases, an inoculation eschar. In recent years, R. felis has acquired an important role in the etiology of the acute febrile syndrome; it is indeed an emerging infectious disease, albeit underdiagnosed. Indirect immunofluorescence assay (IFA) is currently the reference diagnostic method. However, this technique has limitations related to the cross reactivity among different species of rickettsiae. Herein, we describe a case of a 16 year-old patient with an acute febrile syndrome secondary to probable infection with R. felis.

Rickettsiosis transmitidas por garrapatas en las Américas: avances clínicos y epidemiológicos, y retos en el diagnóstico / Tick-borne rickettsioses in the Americas: clinical and epidemiological advances, and diagnostic challenges

Las rickettsiosis son entidades clínicas de tipo zoonótico, causadas por bacterias intracelulares estrictas de los géneros Rickettsia y Orientia, pertenecientes a la familia Rickettsiaceae. Su ecología está determinada por factores ambientales y la presencia de vectores específicos que condicionan el establecimiento y la epidemiología en diferentes regiones del mundo. En las Américas, durante el siglo XX, únicamente eran reconocidas tres de estas enfermedades: la fiebre manchada de las Montañas Rocosas, el tifus epidémico y el tifus endémico, Sin embargo, a partir del año 2000 se han descrito mas de 10 especies diferentes previamente desconocidas en este continente, tanto en artrópodos como en casos clínicos, hecho que permite clasificarlas como entidades clínicas emergentes y reemergentes. Dadas las manifestaciones clínicas de las enfermedades causadas por rickettsias, siendo la gran mayoría inespecíficas y, por lo mismo, compartidas con otras enfermedades infecciosas, especialmente virales y bacterianas, han sido enmarcadas entre los diagnósticos diferenciales del síndrome febril agudo, tanto en áreas urbanas como tropicales. En la actualidad, se cuenta con métodos diagnósticos directos e indirectos, que son útiles en la identificación del agente infeccioso, en este caso, causante de rickettsiosis.

Rickettsioses are a group of zoonotic diseases caused by strict intracellular bacteria of the genus Rickettsia and Orientia which belong to the Rickettsiaceae family. Their ecology is influenced by environmental factors and the presence of specific vectors that determine the establishment and epidemiology in different world regions. In America, during the 20 th century, only three of these diseases were recognized: Rocky Mountain spotted fever, epidemic typhus and endemic typhus. However, since 2000, more than 10 different species that had previously been unknown in this continent have been described, both in arthropods and in clinical cases, fact that classifies them as emerging and re-emerging diseases. Given the clinical manifestations of the diseases caused by rickettsias, being the majority unspecific and, therefore, shared with other infectious diseases, especially viral and bacterial, they have been framed within the differential diagnoses of acute febrile syndrome in urban and tropical areas. Nowadays, there are direct and indirect diagnostic methods, which are useful in the definition of the infectious agent, in this case, the cause of rickettsioses.

Molecular detection of Rickettsia felis in different flea species from Caldas, Colombia.

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.

Flea-borne rickettsioses in the north of Caldas province, 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.

Leucemia mieloide aguda durante el embarazo: reporte de un caso / Acute myeloid leukemia during pregnancy: case report

Se trata de primigesta de 18 años, etnia wayuu, con amenorrea de 30,5 semanas, quien acude en condiciones clínicas de cuidado por presentar disnea acentuada desde hace una semana. El examen físico demostraba palidez cutánea marcada, hiperplasia gingival, soplo holosistólico grado I, taquisfigmia, murmullo vesicular abolido en ambas bases pulmonares con crepitantes bilaterales, abdomen globoso, útero grávido, AU: 27 cm, feto cefálico activo, tacto sin modificaciones. Presenta anemia, marcada leucocitosis, hipoproteinemia, elevación de LDH, y patrón de consolidación bibasal en radiografía pulmonar. Ingresa con diagnóstico de embarazo simple pretérmino, neumonía bilateral, enfermedad linfoproliferativa, y sepsis (?); durante su evolución presenta alteración en el perfil biofísico fetal y hemodinámico, practicándose cesárea segmentaria debido a oligoamnios y sufrimiento fetal agudo. Se obtiene neonato pretérmino, el cual ingresa por prematuridad, sepsis neonatal y enfermedad de membrana hialina. Frotis de sangre periférica revela leucopenia con predominio de monocitos, trombocitopenia, anisocitosis, hipocromia, y macroplaquetas; mientras que el aspirado de médula ósea presentaba 80 % de infiltración de mieloblastos y alteraciones en la citometría de flujo. Recibe quimioterapia según protocolo BMS y manejo médico de las complicaciones presentadas, fallece durante el puerperio tardío.

Primigravida 18 years, ethnicity Wayuu, with 30.5 weeks of amenorrhea, who went into clinical conditions of care for presenting accentuated dyspnea since a week ago. Physical examination showed marked skin pallor, gingival hyperplasia, holosystolic blow, palpitations, vesicular murmur abolished in lung’s bases with bilateral crackles. Abdomen with graves uterus, height 27cm, and cephalic active fetus; vaginal touch unchanged. Presents anemia, marked leukocytosis, hypoproteinaemia, elevated LDH, and pattern of consolidation at lung’s radiographers. She is admitting with diagnosed of preterm pregnancy, bilateral pneumonia, lymphoproliferative disease, and sepsis (?); during its evolution presents impaired fetal biophysical profile and hemodynamic, practised caesarean operation due to oligoamnios and acute fetal distress. Obtained preterm infant, who was admitted because of prematurity, neonatal sepsis and hyaline membrane disease. Peripheral blood smear reveals predominantly monocytes leukopenia, thrombocytopenia, anisocitosis, hipocromia and macroplaquets. While the bone marrow aspirate showed 80 % of infiltration mieloblasts cells and alterations in the cytometry of flow. Receives chemotherapy by protocol BMS and medical management of complications presented, dies during the late puerperium.

[Probable case of flea-borne spotted fever (Rickettsia felis)]. / Caso probable de fiebre manchada (Rickettsia felis) transmitida por pulgas.

Rickettsia felis is the etiologic agent of flea-borne spotted fever, with Ctenocephalides felis as its main vector and reservoir. Typically, the disease presents as acute fever associated with headache, asthenia, generalized maculo-papular rash, and in some cases, an inoculation eschar. In recent years, R. felis has acquired an important role in the etiology of the acute febrile syndrome; it is indeed an emerging infectious disease, albeit underdiagnosed. Indirect immunofluorescence assay (IFA) is currently the reference diagnostic method. However, this technique has limitations related to the cross reactivity among different species of rickettsiae. Herein, we describe a case of a 16 year-old patient with an acute febrile syndrome secondary to probable infection with R. felis.

[Tick-borne rickettsioses in the Americas: clinical and epidemiological advances, and diagnostic challenges]. / Rickettsiosis transmitidas por garrapatas en las Américas: avances clínicos y epidemiológicos, y retos en el diagnóstico.

Rickettsioses are a group of zoonotic diseases caused by strict intracellular bacteria of the genus Rickettsia and Orientia which belong to the Rickettsiaceae family. Their ecology is influenced by environmental factors and the presence of specific vectors that determine the establishment and epidemiology in different world regions. In America, during the 20 th century, only three of these diseases were recognized: Rocky Mountain spotted fever, epidemic typhus and endemic typhus. However, since 2000, more than 10 different species that had previously been unknown in this continent have been described, both in arthropods and in clinical cases, fact that classifies them as emerging and re-emerging diseases. Given the clinical manifestations of the diseases caused by rickettsias, being the majority unspecific and, therefore, shared with other infectious diseases, especially viral and bacterial, they have been framed within the differential diagnoses of acute febrile syndrome in urban and tropical areas. Nowadays, there are direct and indirect diagnostic methods, which are useful in the definition of the infectious agent, in this case, the cause of rickettsioses.

Respuesta sexual en mujeres posmenopáusicas / Sexual response in postmenopausal women

Comparar la respuesta sexual en mujeres posmenopáusicas según el tipo de menopausia presentada. Se estudiaron 120 pacientes divididas en dos grupos pareados, las cuales fueron valoradas mediante un cuestionario de 46 ítems a través de una escala de Lickert, validado mediante el juicio de expertos y el coeficiente Alfa-Cronbach (0.94). Maternidad Dr. Armando Castillo Plaza, Maracaibo. Durante la excitación, sus indicadores en las menopáusicas naturales se ubicaron en las categorías alta o moderada; mientras que en las histerectomizadas en moderada o baja. En el orgasmo, los indicadores analizados se encontraron en iguales categorías, salvo el indicador tipos de estimulación que resultó alto en las que presentaron menopausia natural y bajo en las quirúrgicas. Por su parte, en las fases de meseta y resolución los indicadores se mostraron en categorías similares. Existen diferencias significativas en las fases de excitación y orgasmo entre ambos grupos, reflejando en las mujeres que tuvieron una menopausia natural bienestar sexual, vida placentera y salud

To compare the sexual response in postmenopausal women according with the menopause type showed. One thousand twenty patients were studied, divided into two matched groups, which were assessed through a questionnaire comprising 46 items through a Lickert´s scale, validated by expert opinion and the Cronbach alpha coefficient (0.94). “Dr. Armando Castillo Plaza” Maternity Center, Maracaibo. During the arousal phase, all indicators were located in the high or moderate category in natural menopausal, while in the hysterectomized women were moderate or low. In the orgasm phase, analyzed indicators were in same categories, although stimulation type in natural menopausal women was high and low in the hysterectomized. Meanwhile, in plateau and resolution phases, the indicators were showed in similar categories. There are significant differences in arousal and orgasm phases between the two groups reflecting in the natural menopausal sexual wellness, pleasant life and health

Outbreak of Rocky Mountain spotted fever in Córdoba, Colombia.

Rocky Mountain spotted fever (RMSF) is a tick-borne disease caused by the obligate intracellular bacterium Rickettsia rickettsii. Although RMSF was first reported in Colombia in 1937, it remains a neglected disease. Herein, we describe the investigation of a large cluster of cases of spotted fever rickettsiosis in a new area of Colombia.

Outbreak of Rocky Mountain spotted fever in Córdoba, Colombia

Rocky Mountain spotted fever (RMSF) is a tick-borne disease caused by the obligate intracellular bacterium Rickettsia rickettsii. Although RMSF was first reported in Colombia in 1937, it remains a neglected disease. Herein, we describe the investigation of a large cluster of cases of spotted fever rickettsiosis in a new area of Colombia.

Patogénesis de las infecciones producidas por rickettsias en las Américas / Pathogenesis of infections caused by rickettsiae in the Americas

Colombia fue el segundo país en reportar rickettsiosis en Latino América (en el año de 1.937); el primero fue Brasil. Estos primeros casos reportados correspondieron a un brote de fiebre de las Montañas Rocosas que ocurrió en la localidad de Tobia, Cundinamarca (1). Además, hasta mediados de los años 40 del siglo pasado, el tifo epidémico (causado por R. prowazekii) era endémico en muchas ciudades de Colombia, incluyendo Bogotá.

A survey of antibodies against Rickettsia rickettsii and Ehrlichia chafeensis in domestic animals from a rural area of Colombia.

In a rural area of Colombia endemic for Rocky Mountain spotted fever, we performed indirect immunofluorescent antibody assays for Rickettsia spp. and Ehrlichia spp. using sera from randomly sampled dogs and horses to test the use of domestic animals as possible sentinels. Antibodies against Ehrlichia spp. were detected in 8 dogs (31.8%). Antibody titers against Rickettsia rickettsii antigen were positive in 4 dogs (18.2%) and 26 horses (16.3%). These values, albeit not directly comparable, are lower than those previously reported for humans in this region. A systemic approach to understanding dynamics of transmission is needed before implementing the use of domestic animals for disease surveillance activities.

Geographic variation in risk factors for SFG rickettsial and leptospiral exposure in Colombia.

In order to characterize the patterns of human exposure to spotted fever group (SFG) rickettsial and leptospiral infection, IgG surveys were conducted on 642 residents of ten different areas of the rural district of Necoclí, Colombia. Areas were selected based on forest cover and human settlement pattern, and individual risk factors were elucidated through multivariate logistic models, controlling for variance clustering within communities. Overall, prevalence of high antibody titers indicating previous exposure to SFG rickettsia and leptospira was 29.2% and 35.6%, respectively, and both were most prevalent in the same peri-urban neighborhood. Forest cover .10% demonstrated the strongest independent association with leptospiral exposure, followed by homes with outdoor storage sheds. Isolated rural housing was the only variable independently associated with SFG rickettsia exposure. Community-level variables significantly modified the effects of individual risk factors. For both pathogens the eldest quartile was less exposed in periurban areas although there was no age effect overall for either. Females living in population settlements were more exposed to SFG rickettsiae but there was no sex association in isolated rural houses. Similarly, in sites with forest cover .10%, individuals working at home had higher leptospira seroprevalence, but place of work was not a risk factor in areas of forest cover ,10%. These data suggest that the patterns of maintenance and/or exposure to leptospira and rickettsia vary across different human created landscapes and settlement patterns. While contrasting risk factors may reflect the unique transmission cycles of each pathogen, the observed patterns of geographic variation suggest that both diseases may respond similarly larger scale human-ecological dynamics.