Antibody Seroprevalence to Spotted Fever Group Rickettsiae in Miraflores, Colombia: A Cross-Sectional Study in Humans and Dogs.

Tick-borne disease burdens are increasing globally, impacting mostly rural and vulnerable communities. Among the most important emerging tick-borne pathogens are the Rickettsia species within the spotted fever group (SFGR) because of their genetic diversity and high lethality rate. Colombia is highly affected by SFGR despite not being reportable diseases; thus, research and clinical management are neglected. Although some departments have demonstrated high seroprevalence rates, in others, such as Boyacá Department, seroprevalence is unknown. Rickettsioses have not been described in Boyacá since 1943, and conversations with local physicians raised suspicions of recent undiagnosed disease compatible with rickettsiosis in some rural areas of the department, warranting epidemiological investigation. Using biobanked human and canine samples from a previous 2021 vector-borne disease study in Miraflores municipality, Boyacá, we had an opportunity to unearth SFGR's exposure in the region. Samples were evaluated using IgG indirect fluorescent assays against SFGR and complemented by survey questionnaires evaluating associated factors. Findings yielded first-time SFGR serological evidence in Boyacá with a 26.5% seroprevalence among dogs and a 20.4% among humans. Human and dog seroprevalences were positively associated, suggesting the presence of domestic transmission. Owning a greater number of domestic animals (prevalence ratio adjusted for all measured factors [aPR], 1.52) and living near crop fields (aPR, 7.77) were associated with an increased likelihood of household seropositivity. Our findings are consistent with the literature in Colombia, uncovering a suspected region where the disease is endemic. Future studies are warranted to continue defining high-risk areas to determine public health intervention plans.

Eco-epidemiological study of seropositivity against Rickettsia and Leptospira agents in rural areas of Urabá, Colombia.

Rickettsioses and leptospirosis are infectious diseases that are often underdiagnosed due to a lack of knowledge about their epidemiology, pathophysiology, diagnosis, management, among others. Objetive: to characterize the seroprevalence and seroincidence of both Rickettsia and Leptospira agents and determine the risk factors for these outcomes in rural areas of Urabá, Antioquia. Methods: a secondary data analysis using information on Rickettsia and Leptospira exposure from a prior prospective study that explored sociocultural and ecological aspects of Rickettsia infection in rural Urabá, Colombia. A multinomial mixed logistic regression model was employed to analyze factors linked to seroprevalent cases of Rickettsia, Leptospira and both, along with descriptive analyses of seroincident cases. Results: the concomitant seroprevalence against Rickettsiaand Leptospira was 9.38% [95%CI 6.08%-13.37%] (56/597). The factors associated with this seroprevalence were age (ORa= 1.02 [95%CI 1.007-1.03]), male gender (ORa= 3.06 [95%CI 1.75-5.37]), fever history (ORa= 1.71 [95%CI 1.06-2.77]) the presence of breeding pigs (ORa= 2.29 [95%CI 1.36-3.88]), peridomicile yucca crops(ORa= 2.5 [95%CI 1.1-5.62]), and deforestation practices(ORa= 1.74 [95%CI 1.06-2.87]). The concomitant seroincidence against Rickettsia and Leptospira was 1.09% (3/274) [95%CI 0.29%-4.05%], three cases were female, with a median age of 31.83 years-old (IQR 8.69-56.99). At the household level, all the seroincident cases had households built partially or totally with soil floors, wooden walls, and zinc roofs. Two seroincident cases described the presence of equines, canines, and domestic chickens in intra or peri-domicile. Finally, two cases were exposed to synanthropic rodents, and one case to tick infestation. Conclusion: there is evidence of seroprevalent and seroincident cases of seropositivity against both Rickettsia and Leptospira in rural areas of Urabá, Colombia. These findings can help improve public health surveillance systems in preventing, detecting, and attending to the different clinical cases caused by these pathogens.

Factors associated with differential seropositivity to Leptospira interrogans and Leptospira kirschneri in a high transmission urban setting for leptospirosis in Brazil.

Background: Leptospirosis is a zoonosis caused by pathogenic species of bacteria belonging to the genus Leptospira. Most studies infer the epidemiological patterns of a single serogroup or aggregate all serogroups to estimate overall seropositivity, thus not exploring the risks of exposure to distinct serogroups. The present study aims to delineate the demographic, socioeconomic and environmental factors associated with seropositivity of Leptospira serogroup Icterohaemorraghiae and serogroup Cynopteri in an urban high transmission setting for leptospirosis in Brazil. Methods/Principal Findings: We performed a cross-sectional serological study in five urban informal communities in the city of Salvador, Brazil. During the years 2018, 2020 2021, we recruited 2.808 residents and collected blood samples for serological analysis using microagglutination assays. We used a mixed-effect multinomial logistic regression model to identify risk factors associated with seropositivity for each serogroup. Seropositivity to Cynopteri increased with age in years (OR 1.03; 95% CI 1.01-1.06) and was higher in those living in houses with unplaster walls (exposed brick) (OR 1.68; 95% CI 1.09-2.59) and where cats were present near the household (OR 2.00; 95% CI 1.03-3.88). Seropositivity to Icterohaemorrhagiae also increased with age in years (OR 1.02; 95% CI 1.01-1.03) but was higher in males (OR 1.51; 95% CI 1.09-2.10), in those with work-related exposures (OR 1.71; 95% CI 1.10-2.66) or who had contact with sewage (OR 1.42; 95% CI 1.00-2.03). Spatial analysis showed differences in distribution of seropositivity to serogroups Icterohaemorrhagiae and Cynopteri within the five districts where study communities were situated. Conclusions/Significance: Our data suggests distinct epidemiological patterns associated with serogroups Icterohaemorrhagiae and Cynopteri within the high-risk urban environment for leptospirosis and with differences of spatial niches. Future studies must identify the different pathogenic serogroups circulating in low-income areas, and further evaluate the potential role of cats in the transmission of the serogroup Cynopteri in urban settings.

Knowledge, Attitudes, and Practices (KAP) About Antibiotic Use in Hemodialysis Patients with Chronic Kidney Disease and Their Household Contacts, Medellín-Colombia.

Purpose: The lack of knowledge and the excessive and inappropriate use of antibiotics are some of the causes of bacterial resistance. Hemodialysis patients have a high consumption of antibiotics and are constantly cared by their household contacts. This population circulates between hospital and community and are a model to study knowledge regarding bacterial resistance and antibiotic use in these settings. This study describes the knowledge, attitudes and practices (KAP) about antibiotic use and bacterial resistance in hemodialysis patients and their household contacts in Medellín-Colombia. Patients and Methods: A cross-sectional descriptive study was conducted on hemodialysis patients from a renal unit associated with a hospital in Medellín-Colombia, and their household contacts between May 2019 and March 2020. A KAP instrument was applied to participants during home visits. The KAP regarding antibiotic use were characterized, and a content analysis of open questions was made. Results: A total of 35 hemodialysis patients and 95 of their household contacts were included. Of participants, 83.1% (108/130) did not correctly identify the situations in which antibiotics should be used. Likewise, a gap in knowledge about antibacterial resistance was evidenced thanks to the emerging categories in content analysis. Regarding attitudes, 36.9% (48/130) of the participants discontinued antibiotic treatment when they felt better. Additionally, 43.8% (57/130) agree to keep antibiotics in their home. Finally, it was found that it is usual for pharmacists and family members to recommend or sell antibiotics without prescription; likewise, pharmacies were the most popular place to acquire these medications. Conclusion: This study identified gaps in KAP regarding the use of antibiotics and bacterial resistance in hemodialysis patients and their household contacts. This allows focusing education strategies in this regard, in order to increase awareness about the correct use of antibiotics and the consequences of bacterial resistance and to improve prevention actions in this vulnerable population.

Leptospira Infection in Rural Areas of Urabá Region, Colombia: A Prospective Study.

The objective of this study was to analyze the eco-epidemiological aspects of Leptospira seroprevalence and seroincidence and its associated factors in two municipalities of northwest Colombia. A prospective study was performed in rural areas of Urabá, Antioquia, Colombia. The study enrolled 597 people between November 2015 and January 2016, of which 274 were followed up 1 year later. Serologic testing was performed by a microscopic agglutination. The outcomes were seroprevalent and seroincident cases, and the primary exposure was an outdoor occupation. A binary and mixed-effect multinomial logistic regression model was used to estimate factors associated with seroprevalent or seroincident cases of Leptospira infection. The overall Leptospira seroprevalence was 27.81% (95% confidence interval: 23.62-32.49), and the overall cumulative seroincidence for Leptospira was 14.60% (95% confidence interval: 10.33-20.23). Multivariable analysis showed that factors associated with L. interrogans serogroups seropositivity were outdoor occupation, male gender, older age, the presence of dirt floor in the household, and the presence of piglets and opossums. It also showed that factors associated with other Leptospira species serogroups were the presence of pit latrines and of turkeys. In addition, the multivariable model of seroincident cases of L. interrogans serogroups evidenced outdoor occupations, the presence of rats, and corn cultivation as risk factors. Likewise, the multivariable model for seroincident cases of other Leptospira species showed that the presence of hunting canines and cassava cultivation were risk factors. We found specific factors associated with the transmission of Leptospira serogroups contribute to the understanding of the epidemiology of Leptospira infection in rural areas of Urabá, Colombia.

Epidemiology of Rickettsial Infection in the Municipality of Uramita, Colombia.

This study aimed to analyze epidemiological indicators related to seroprevalent and seroincident cases of spotted fever group rickettsiae (SFGR) and to identify housing conditions related to tick infestation. A prospective study (2016-2018) was conducted to examine rickettsial seropositivity in humans, domestic animals, and wild mammals in the municipality of Uramita, Antioquia, Colombia, where a previous Rickettsia rickettsii outbreak was reported from 2014 to 2015. The seroprevalence and its associated factors were estimated at baseline, and the seroincidence and its risk factors for humans were estimated 20 months later. A cross-sectional analysis was performed to evaluate the housing conditions linked to tick infestation. The SFGR seroprevalence was 26.70% (95% confidence interval [CI], 20.79-31.37), and the factors associated with SFGR seropositivity were male sex (adjusted prevalence ratio [PRa], 1.67; 95% CI, 1.19-2.32), age (evaluated in 5-year increments) (PRa, 1.05; 95% CI, 1.01-1.09), and household proximity (PRascattered vs. very near=3.87; 95% CI, 1.12-8.66). The overall seroincidence was 7.40% (95% CI, 4.71-11.06), and the factors associated with SFGR seroincident cases were the presence of wild animals (adjusted relative risk [RRa], 2.46; 95% CI, 1.06-4.72) and the presence of trees in the peri-domiciliary area (RRa, 0.47; 95% CI, 0.23-0.94). The prevalence of house tick infestation was 27.81% (95% CI, 21.93-34.80), and the factors associated with infestation were dirt floors (PRa, 5.88; 95% CI, 2.28-10.31), fiber cement roofs (PRa, 1.76; 95% CI, 1.07-2.83), and the presence of canines in peri-domiciliary or intra-domiciliary areas (PRa, 5.05; 95% CI, 3.31-7.19). Seropositivity rates for canines and opossums were 35.62% (26/73) and 100% (6/6), respectively. Identification of these factors will help to implement efficient surveillance programs in Colombia.

Fatal Rickettsia rickettsii infection in a child, Northwestern Colombia, 2017.

This report describes a new lethal case of Rickettsia rickettsii infection in a child from Northwestern Colombia, after ten years of the last outbreaks in the same region. Colombian public-health authorities should consider to include this severe rickettsiosis in the compulsory-reporting diseases, with the aim of knowing its burden in the country.