Background: Intestinal parasitic protozoa represent a serious problem of public health particularly in developing countries. Protozoa such as Blastocystis, Giardia intestinalis, Entamoeba histolytica and Cryptosporidium spp. are associated with diarrheal symptoms. In Colombia, there is little region-specific data on the frequency and circulating genotypes/species of these microorganisms. Therefore, the main objective of our study was to employ molecular detection and genotyping of G. intestinalis and Blastocystis, Cryptosporidium and Entamoeba spp. in samples from different biogeographical regions of Colombia. Methods: We collected 649 human fecal samples from five biogeographical regions of Colombia: the Amazon, Andean, Caribbean, Orinoco and Pacific regions. Blastocystis, G. intestinalis, Cryptosporidium spp. and Entamoeba complex were detected by microscopy and conventional PCR. Molecular genotyping was conducted to identify Blastocystis subtypes (STs) (18s), G. intestinalis assemblages (triose phosphate isomerase and glutamate dehydrogenase) and Cryptosporidium species (18s). Genetic diversity indices were determined using dnasp.5. Results: We detected G. intestinalis in 45.4% (n = 280) of samples, Blastocystis in 54.5% (n = 336) of samples, Cryptosporidium spp. in 7.3% (n = 45) of samples, Entamoeba dispar in 1.5% (n = 9) of samples, and Entamoeba moshkovskii in 0.32% (n = 2) of samples. Blastocystis STs 1–4, 8 and 9 and G. intestinalis assemblages AII, BIII, BIV, D and G were identified. The following Cryptosporidium species were identified: C. hominis, C. parvum, C. bovis, C. andersoni, C. muris, C. ubiquitum and C. felis. The Caribbean region had the highest frequency for each of the microorganisms evaluated (91.9% for G. duodenalis, 97.3% for Blastocystis, 10.8% for Cryptosporidium spp., 13.5% for E. dispar and 2.7% for E. moshkovskii). The Orinoco region had a high frequency of Blastocystis (97.2%) and the Andean region had a high frequency of G. intestinalis (69.4%). High and active transmission was apparent in several regions of the country, implying that mechanisms for prevention and control of intestinal parasitosis in different parts of the country must be improved.

Pseudomonas aeruginosa Sequence Type 235 is a clone that possesses an extraordinary ability to acquire mobile genetic elements and has been associated with the spread of resistance genes, including genes that encode for carbapenemases. Here, we aim to characterize the genetic platforms involved in resistance dissemination in blaKPC-2-positive P. aeruginosa ST235 in Colombia. In a prospective surveillance study of infections in adult patients attended in five ICUs in five distant cities in Colombia, 58 isolates of P. aeruginosa were recovered, of which, 27 (46.6%) were resistant to carbapenems. The molecular analysis showed that 6 (22.2%) and 4 (14.8%) isolates harboured the blaVIM and blaKPC-2 genes, respectively. The four blaKPC-2-positive isolates showed a similar PFGE pulsotype and belonged to ST235. Complete genome sequencing of a representative ST235 isolate shows a unique chromosomal contig of 7097.241 bp with eight different resistance genes identified and five transposons: a Tn6162-like with ant(2″)-Ia, two Tn402-like with ant(3″)-Ia and blaOXA-2 and two Tn4401b with blaKPC-2. All transposons were inserted into the genomic islands. Interestingly, the two Tn4401b copies harbouring blaKPC-2 were adjacently inserted into a new genomic island (PAGI-17) with traces of a replicative transposition process. This double insertion was probably driven by several structural changes within the chromosomal region containing PAGI-17 in the ST235 background. This is the first report of a double Tn4401b chromosomal insertion in P. aeruginosa, just within a new genomic island (PAGI-17). This finding indicates once again the great genomic plasticity of this microorganism.

Cytokines and chemokines are immune response molecules that display diverse functions, such as inflammation and immune regulation. In Plasmodium vivax infections, the uncontrolled production of these molecules is thought to contribute to pathogenesis and has been proposed as a possible predictor for disease complications. The objective of this study was to evaluate the cytokine profile of P. vivax malaria patients with different clinical outcomes to identify possible immune biomarkers for severe P. vivax malaria. The study included patients with non-severe (n = 56), or severe (n = 50) P. vivax malaria and healthy controls (n = 50). Patient plasma concentrations of IL-4, IL-2, CXCL10, IL-1β, TNF-α, CCL2, IL-17A, IL-6, IL-10, IFN-γ, IL-12p70, CXCL8 and active TGF-β1 were determined through flow cytometry. The levels of several cytokines and chemokines, CXCL10, IL-10, IL-6, IL-4, CCL2 and IFN-γ were found to be significantly higher in severe, compared to non-severe P. vivax malaria patients. Severe thrombocytopenia was positively correlated with IL-4, CXCL10, IL-6, IL-10 and IFN-γ levels, renal dysfunction was related to an increase in IL-2, IL-1β, IL-17A and IL-8, and hepatic impairment with CXCL10, MCP-1, IL-6 and IFN-γ. A Lasso regression model suggests that IL-4, IL-10, CCL2 and TGF-β might be developed as biomarkers for severity in P. vivax malaria. Severe P. vivax malaria patients present specific cytokine and chemokine profiles that are different from non-severe patients and that could potentially be developed as biomarkers for disease severity.

Plasmodium vivax has high morbidity, it is the Plasmodium species with the greatest worldwide distribution, and its ability to trigger severe symptoms is currently recognized. The present study aims to compare the clinical and epidemiological characteristics of patients with P. vivax malaria, with and without complication criteria, in an endemic area for malaria transmission in northwest Colombia. A descriptive cross-sectional study was carried out between 2017 and 2019, patients with P.vivax severe malaria (n = 50), non-severe malaria (n = 56) and healthy controls (n = 50) were included. Sociodemographic, clinical, hematological, and biochemical characteristics were analyzed. Clinical follow-up was carried out in a group of patients with severe malaria. The statistical analysis was carried out in GraphPad Prism; the Chi-square test analyzed categorical variables, comparisons of variables for the three groups were carried out by the Kruskal-Wallis test and comparison between two groups by the Mann-Whitney test. A multiple correspondence analysis described the relationship between variables, which was carried out through the R software. One hundred fifty-six individuals were linked to the study, 76 women and 80 men, between 3 and 71 years old. For 50% of the patients, it was their first malaria episode; 42% of the patients classified with severe malaria required hospitalization, compared to 7.1% of the patients with non-severe malaria. Parasitaemia was similar in both clinical groups; however, 10% of severe patients presented high parasitemia, between 20,000-135,000. The most frequent clinical characteristics in patients with severe malaria were severe thrombocytopenia in 54%, hypoglycemia in 48%, and liver and kidney failure in 30%. Biochemical and hematological parameters returned to normal in 90% of the patients with severe malaria on the third day after starting treatment. Thrombocytopenia, hypoglycemia, and liver and kidney dysfunctions were the most frequent P. vivax malaria complications in this study. Hemoglobin concentration and parasite count were not related to the clinical condition of patients. Thrombocytopenia was the most frequent finding in patients with malaria, and its severity presented an inverse relationship with the number of previous malaria episodes.

Malaria remains a worldwide public health concern and, in Colombia, despite the efforts to stop malaria transmission, the incidence of cases has increased over the last few years. In this context, it is necessary to evaluate vector diversity, infection rates, and spatial distribution, to better understand disease transmission dynamics. This information may contribute to the planning and development of vector control strategies. A total of 778 Anopheles mosquitoes were collected in fifteen localities of Córdoba from August 2015 to October 2016. Six species were identified and overall, Anopheles albimanus was the most widespread and abundant species (83%). Other species of the Nyssorhynchus subgenus were collected, including Anopheles triannulatus (13%), Anopheles nuneztovari (1%), Anopheles argyritarsis (< 1%) and two species belonging to the Anopheles subgenus: Anopheles pseudopunctipennis (3%) and Anopheles neomaculipalpus (< 1%). Four species were found naturally infected with two Plasmodium species: Anopheles nuneztovari was detected naturally infected with Plasmodium falciparum and Anopheles pseudopunctipennis with Plasmodium vivax, whereas An. albimanus and An. triannulatus were found infected with both parasite species and confirmed by nested PCR. In general, the obtained results were contrasting with previous studies in terms of the most abundant and widespread collected species, and regarding infection rates, which were higher than those previously reported. A positive relationship between mosquito local abundance at the locality level and human infection at the municipality level was found. Mosquito local abundance and the number of houses with mosquitoes in each village are factors explaining malaria human cases in these villages. The obtained results suggest that other factors related to the apparent variation in malaria eco-epidemiology in northern Colombia, must be identified, to provide health authorities with better decision tools aiming to design control and prevention strategies.

Este artículo se centra en las concepciones, actitudes y prácticas de los pobladores de cuatro veredas en Tierralta y Valencia (Córdoba, Colombia), que han padecido o conocen la leishmaniasis cutánea. Se implementó una metodología mixta que combinó un diseño cualitativo con entrevistas y grupos focales (n=45), y un diseño epidemiológico en el que se aplicó la prueba de Montenegro (n=251), se relevaron casos sospechosos de leishmaniasis cutánea en humanos (n=5) y se realizaron encuestas epidemiológicas (n=409). Entre los resultados se encontró que hay un desconocimiento del vector y, aunque identificaron la Lutzomyia (Alú), no la correlacionaron con la leishmaniasis cutánea. Por otra parte los tratamientos tradicionales caseros son los más usados, lo que provoca el aumento del subregistro de casos. Respecto al personal de salud, se encontraron fallas en el diagnóstico y el tratamiento, lo que refuerza la adherencia a tratamientos caseros. Este escenario nos insta a reflexionar acerca de los retos del sistema de salud respecto a las intervenciones del personal de salud en las comunidades asentadas en zonas endémicas.