Bovine leptospirosis: effects on reproduction and an approach to research in Colombia

Leptospirosis is the most widespread zoonosis worldwide, causing severe effects on beef and dairy cattle farming and other livestock. Colombia geographical location in the tropical zone, high biodiversity, and climatic conditions promote Leptospira growth and prevalence. This review article presents state-of-the-art knowledge about the effects of leptospirosis on bovine reproduction and a critical analysis of the research carried out in Colombia. The analysis of the information allows us to infer a sustained increase in prevalence over the last decade in the densest livestock production areas and a high serovar diversity of circulating pathogenic Leptospira. Given the zoonotic nature of leptospirosis, an inter-institutional effort is required to implement prevention, control, and monitoring programs under one-health concept.

Seroprevalence of antibodies to Chlamydia abortus and risk factors in cattle from Villavicencio, Colombia

Chlamydia abortus is a Gram-negative obligate intracellular bacterium, responsible for abortions and reproductive problems. The disease has a high zoonotic potential and causes great economic losses in ruminant farmers. A cross-sectional study was carried out with 514 cattle from 24 farms of Villavicencio, Colombia. The blood samples were collected from each individual animal and analyzed by Indirect Elisa for immunoglobulin G (IgG) in blood serum (Idexx Chlamydiosis total Ab test). A serum was considered positive when the optical density (OD) of the sample was ≥30% of that of the positive control serum. Data on potential risk factors associated with the disease were collected through a questionnaire in each farm and analyzed. The individual and herd prevalence was estimated. A risk factors analysis was performed through univariate and multivariable using the software SPSS version 20. The animal level seroprevalence was found to be 47.1% and the herd 91.6%. The prevalence in cattle aged 0-1, 1-3 and >4 years was 23.8%; 31.4% and 51.4% respectively. The risk factors associated with the prevalence of disease were female sex (OR = 2.102 CI: 1.066-4.144), age older than 4 years (OR = 2.707 CI: 1.667-4.394), presence of canines on the farm (OR = 2.556 CI: 1.560-4.189) and retention of placenta (OR = 2.678 CI: 1.670-4.295). A high prevalence was identified, suggesting natural infection where the pathogen could be transmitted to humans at the animal-human interface.

Seasonal variation and natural infection of Lutzomyia antunesi (Diptera: Psychodidae: Phlebotominae), an endemic species in the Orinoquia region of Colombia

Lutzomyia antunesi has been commonly reported in outbreaks of cutaneous leishmaniasis (CL) in the Orinoquia region of Colombia. The bionomics of this species were studied in the municipality of Villavicencio (Meta, Colombia). Sandflies were captured over the course of one week per month for one year in intradomiciliary, peridomiciliary and extradomiciliary housing areas. The captures were performed from 06:00 pm-06:00 am using CDC light traps and the females were processed for polymerase chain reaction (PCR) to detect Leishmania spp. A total of 22,097 specimens and 19 species were captured of which Lu. antunesi (89%) and Lutzomyia walkeri (5%) were the most abundant. Other species recognised as anthropophilic (Lutzomyia panamensis, Lutzomyia gomezi, Lutzomyia flaviscutellata and Lutzomyia fairtigi) were present in very low abundance (< 2%). Natural infection with Leishmania spp was detected using PCR in Lu. antunesi, Lu. panamensis and Lu. flavicutellata, showing infection rates of 1%, 4.8% and 7.5%, respectively. The present paper provides information on various ecological aspects of Lu. antunesi. An analysis of seasonality shows that this species increases in abundance in the hottest months (December, January and February), directly correlating with the maximum temperature and inversely correlating with precipitation. The natural infection rate is associated with the peaks of highest abundance.

Seasonal variation and natural infection of Lutzomyia antunesi (Diptera: Psychodidae: Phlebotominae), an endemic species in the Orinoquia region of Colombia

Lutzomyia antunesi has been commonly reported in outbreaks of cutaneous leishmaniasis (CL) in the Orinoquia region of Colombia. The bionomics of this species were studied in the municipality of Villavicencio (Meta, Colombia). Sandflies were captured over the course of one week per month for one year in intradomiciliary, peridomiciliary and extradomiciliary housing areas. The captures were performed from 06:00 pm-06:00 am using CDC light traps and the females were processed for polymerase chain reaction (PCR) to detect Leishmania spp. A total of 22,097 specimens and 19 species were captured of which Lu. antunesi (89%) and Lutzomyia walkeri (5%) were the most abundant. Other species recognised as anthropophilic (Lutzomyia panamensis, Lutzomyia gomezi, Lutzomyia flaviscutellata and Lutzomyia fairtigi) were present in very low abundance (< 2%). Natural infection with Leishmania spp was detected using PCR in Lu. antunesi, Lu. panamensis and Lu. flavicutellata, showing infection rates of 1%, 4.8% and 7.5%, respectively. The present paper provides information on various ecological aspects of Lu. antunesi. An analysis of seasonality shows that this species increases in abundance in the hottest months (December, January and February), directly correlating with the maximum temperature and inversely correlating with precipitation. The natural infection rate is associated with the peaks of highest abundance.