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Background: The humoral immune response against Anopheles salivary glands proteins in the vertebrate host can reflect the intensity of exposure to Anopheles bites and the risk of Plasmodium infection. In Colombia, the identification of exposure biomarkers is necessary due to the several Anopheles species circulating. The purpose of this study was to evaluate risk of malaria infection by measuring antibody responses against salivary glands extracts from An. (Nys.) albimanus and An. (Nys.) darlingi and also against the gSG6-P1 peptide of An. gambiae in people residing in a malaria endemic area in the Colombian Pacific coast. Methods: We eluted dried blood spots samples to measure the IgG antibodies against salivary gland extracts of An. (Nys.) albimanus strains STECLA (STE) and Cartagena (CTG) and An. (Nys.) darlingi and the gSG6-P1 peptide by ELISA in uninfected people and microscopic and submicroscopic Plasmodium carriers from the Colombia Pacific Coast. A multiple linear mixed regression model, Spearman correlation, and Mann-Whitney U-test were used to analyze IgG data. Results: Significant differences in specific IgG levels were detected between infected and uninfected groups for salivary glands extracts from An. (Nys.) albimanus and for gSG6-P1, also IgG response to CTG and gSG6-P1 peptide were positively associated with the IgG response to P. falciparum in the mixed model. Conclusion: The CTG and STE An. (Nys.) albimanus salivary glands extracts are a potential source of new Anopheles salivary biomarkers to identify exposure to the main malaria vector and to calculate risk of disease in the Colombian Pacific coast. Also, the gSG6-P1 peptide has the potential to quantify human exposure to the subgenus Anopheles vectors in the same area.

Additional file 1. Additional table.

Background The humoral immune response against Anopheles salivary glands proteins in the vertebrate host can reflect the intensity of exposure to Anopheles bites and the risk of Plasmodium infection. In Colombia, the identification of exposure biomarkers is necessary due to the several Anopheles species circulating. The purpose of this study was to evaluate human exposure to Anopheles bite by measuring antibody responses against salivary glands extracts from An. albimanus and An. darlingi and also against the gSG6-P1 peptide of An. gambiae in asymptomatic P. falciparum infections in the Colombian Pacific coast.Methods We eluted dried blood spots samples to measure the IgG antibodies against salivary gland extracts of An. albimanus and An. darlingi and the gSG6-P1 peptide by ELISA in uninfected people and microscopic and submicroscopic Plasmodium carriers from the Colombia Pacific Coast. A multiple linear mixed regression model, Spearman correlation, and Mann-Whitney U-test were used to analyze IgG data.Results Significant differences in specific IgG levels were detected between infected and uninfected groups for salivary glands extracts from An. albimanus and for gSG6-P1, also IgG response to CTG and gSG6-P1 peptide were positively associated with the IgG response to P. falciparum in the mixed model.Conclusion The CTG and STE An. albimanus salivary glands extracts are a potential source of new Anopheles salivary biomarkers to identify exposure to the main malaria vector in the Colombian Pacific coast. Also, the gSG6-P1 peptide has the potential to quantify human exposure to the subgenus Anopheles vectors in the same area.

Background The humoral immune response against Anopheles salivary glands proteins in the vertebrate host can reflect the intensity of exposure to Anopheles bites and the risk of Plasmodium infection. In Colombia, the identification of exposure biomarkers is necessary due to the several Anopheles species circulating. The purpose of this study was to evaluate risk of malaria infection by measuring antibody responses against salivary glands extracts from Anopheles (Nyssorhynchus) albimanus and Anopheles (Nys.) darlingi and also against the gSG6-P1 peptide of Anopheles gambiae in people residing in a malaria endemic area in the Colombian Pacific coast. Methods Dried blood spots samples were eluted to measure the IgG antibodies against salivary gland extracts of An. albimanus strains STECLA (STE) and Cartagena (CTG) and An. darlingi and the gSG6-P1 peptide by ELISA in uninfected people and microscopic and submicroscopic Plasmodium carriers from the Colombia Pacific Coast. A multiple linear mixed regression model, Spearman correlation, and Mann–Whitney U-test were used to analyse IgG data. Results Significant differences in specific IgG levels were detected between infected and uninfected groups for salivary glands extracts from An. albimanus and for gSG6-P1, also IgG response to CTG and gSG6-P1 peptide were positively associated with the IgG response to Plasmodium falciparum in the mixed model. Conclusion The CTG and STE An. albimanus salivary glands extracts are a potential source of new Anopheles salivary biomarkers to identify exposure to the main malaria vector and to calculate risk of disease in the Colombian Pacific coast. Also, the gSG6-P1 peptide has the potential to quantify human exposure to the subgenus Anopheles vectors in the same area.

Host genetics is an influencing factor in the manifestation of infectious diseases. In this study, the association of mild malaria with 28 variants in 16 genes previously reported in other populations and/or close to ancestry-informative markers (AIMs) selected was evaluated in an admixed 736 Colombian population sample. Additionally, the effect of genetic ancestry on phenotype expression was explored. For this purpose, the ancestral genetic composition of Turbo and El Bagre was determined. A higher Native American ancestry trend was found in the population with lower malaria susceptibility [odds ratio (OR) = 0.416, 95% confidence interval (95% CI) = 0.234-0.740, P = 0.003]. Three AIMs presented significant associations with the disease phenotype (MID1752, MID921, and MID1586). The first two were associated with greater malaria susceptibility (D/D, OR = 2.23, 95% CI = 1.06-4.69, P = 0.032 and I/D-I/I, OR = 2.14, 95% CI = 1.18-3.87, P = 0.011, respectively), and the latter has a protective effect on the appearance of malaria (I/I, OR = 0.18, 95% CI = 0.08-0.40, P < 0.0001). After adjustment by age, sex, municipality, and genetic ancestry, genotype association analysis showed evidence of association with malaria susceptibility for variants in or near IL1B, TLR9, TREM1, IL10RA, and CD3G genes: rs1143629-IL1B (G/A-A/A, OR = 0.41, 95% CI = 0.21-0.78, P = 0.0051), rs352139-TLR9 (T/T, OR = 0.28, 95% CI = 0.11-0.72, P = 0.0053), rs352140-TLR9 (C/C, OR = 0.41, 95% CI = 0.20-0.87, P = 0.019), rs2234237-TREM1 (T/A-A/A, OR = 0.43, 95% CI = 0.23-0.79, P = 0.0056), rs4252246-IL10RA (C/A-A/A, OR = 2.11, 95% CI = 1.18-3.75, P = 0.01), and rs1561966-CD3G (A/A, OR = 0.20, 95% CI = 0.06-0.69, P = 0.0058). The results showed the participation of genes involved in immunological processes and suggested an effect of ancestral genetic composition over the traits analyzed. Compared to the paisa population (Antioquia), Turbo and El Bagre showed a strong decrease in European ancestry and an increase in African and Native American ancestries. Also, a novel association of two single nucleotide polymorphisms with malaria susceptibility was identified in this study.

Introduction: In Colombia, the published studies for the treatment of uncomplicated Plasmodium falciparum malaria with Artemether-Lumefantrine are scarce. The aim of the study was to evaluate the therapeutic efficacy and safety profile of this combination. Methods: A clinical trial was performed in adults with uncomplicated P. falciparum malaria using the 28‐day World Health Organization validated protocol. Patients received supervised antimalarial treatment and the primary efficacy endpoint was the clinical and parasitological response. Safety was assessed through adverse events surveillance and plasmatic levels of antimalarial drugs were measured. Results: 88 patients were included. Adequate clinical and parasitological response rate of 100% on day 28 was achieved in 84 patients, diagnosed by thick blood smear examination. There were four parasitological therapeutic failures (5%) detected by polymerase chain reaction. Discusion: Therapeutic efficacy similar to previous studies was established with a slight increase in therapeutic failure. The serum levels of the antimalarials were adequate and the few cases of therapeutic failure were not related. Conclusion: Treatment of uncomplicated P. falciparum malaria with Artemeter-Lumefantrine was effective and safe in the study population. All patients reached adequate plasma concentrations of the drugs; therapeutic failures were not associated with low blood levels of the drug clinical trial. COL0007524

Insect saliva induces significant antibody responses associated with the intensity of exposure to bites and the risk of disease in humans. Several salivary biomarkers have been characterized to determine exposure intensity to Old World Anopheles mosquito species. However, new tools are needed to quantify the intensity of human exposure to Anopheles bites and understand the risk of malaria in low-transmission areas in the Americas. To address this need, we conducted proteomic and bioinformatic analyses of immunogenic candidate proteins present in the saliva of uninfected Anopheles albimanus from two separate colonies&mdash, one originating from Central America (STECLA strain) and one originating from South America (Cartagena strain). A ~65 kDa band was identified by IgG antibodies in serum samples from healthy volunteers living in a malaria endemic area in Colombia, and a total of five peptides were designed from the sequences of two immunogenic candidate proteins that were shared by both strains. ELISA-based testing of human IgG antibody levels against the peptides revealed that the transferrin-derived peptides, TRANS-P1, TRANS-P2 and a salivary peroxidase peptide (PEROX-P3) were able to distinguish between malaria-infected and uninfected groups. Interestingly, IgG antibody levels against PEROX-P3 were significantly lower in people that have never experienced malaria, suggesting that it may be a good marker for mosquito bite exposure in na&iuml, ve populations such as travelers and deployed military personnel. In addition, the strength of the differences in the IgG levels against the peptides varied according to location, suggesting that the peptides may able to detect differences in intensities of bite exposure according to the mosquito population density. Thus, the An. albimanus salivary peptides TRANS-P1, TRANS-P2, and PEROX-P3 are promising biomarkers that could be exploited in a quantitative immunoassay for determination of human-vector contact and calculation of disease risk.

The essential oils from Lippia alba (Miller) N.E Brown (Verbenaceae Family) collected in different regions of Colombia were obtained by microwave-assisted hydrodistillation. Their chemical compositions were determined by GC and GC/MS. Two chemotypes were distinguished, characterized by carvone and citral as main constituents. Antifungal activity of the essential oils was determined following the standard microdilution protocols AFST-EUCAST for C. krusei and C. parasilopsis, and CLSI-M38A for Aspergillus fumigatus and A. flavus. The essential oils obtained from both L. alba chemotypes showed antifungal activity.

Background European (E) variants of HPV 16 are evenly distributed among world regions, meanwhile Non-European variants such as European-Asian (EAs), Asian American (AA) and African (Af) are mostly confined to Eastern Asia, The Americas and African regions respectively. Several studies have shown that genetic variation of HPV 16 is associated with the risk of cervical cancer, which also seems to be dependent on the population. This relationship between ethnicity and variants have led to the suggestion that there is co-evolution of variants with humankind. Our aim was to evaluate the relationship between the individual ancestry proportion and infection with HPV 16 variants in cervical cancer. Methods We examined the association between ancestry and HPV 16 variants in samples of 82 cervical cancer cases from different regions of Colombia. Individual ancestry proportions (European, African and Native American) were estimated by genotyping 106 ancestry informative markers. Variants were identified by PCR amplification of the E6 gene, followed by reverse line blot hybridization (RLB) with variants specific probes. Results Overall European (E) and Asian American (AA) variants frequency was 66.5% and 33.5% respectively. Similar distribution was observed in cases with higher proportions of European or African ancestry. A higher Native American ancestry was significantly associated with higher frequency of E variants (median ancestry > 23.6%, Age and place of birth adjusted OR: 3.55, 95% CI: 1.26–10.03, p = 0.01). Even further, an inverse geographic correlation between Native American ancestry and frequency of infections with AA variants was observed (ρ = −0.825, p = 0.008). Regions with higher proportion of Native American ancestry had a lower frequency of AA variants of HPV 16. Conclusions This study suggests replacement of AA variants by E variants of human papillomavirus 16 in cervical cancer cases with high Native American ancestry.

Introduccion El desarrollo de todos los casos de cancer cervical esta asociado a la infeccion por el Virus del Papiloma Humano (VPH). Aunque la mayoria de las mujeres infectadas son capaces de aclarar la infeccion, algunas desarrollan cancer, sugiriendo que existen co-factores relacionados con la neoplasia cervical. El antigeno leucocitario humano (HLA) clase I media la presentacion de los antigenos del VPH al sistema inmune y de esta forma puede proteger o predisponer a la neoplasia cervical. Previos estudios han sugerido una asociacion entre ciertos alelos de HLA con cancer cervical, pero los resultados no son consistentes. En Colombia no se han desarrollado estudios que evaluen esta asociacion. Objetivo Determinar la asociacion entre ciertos alelos de HLA-I y cancer cervical en la poblacion de Antioquia. Materiales y metodos Estudio de casos y controles. Se incluyeron 143 casos de cancer cervical y 127 controles emparejados por grupos de edad y lugar de nacimiento. La tipificacion de HLA-A y B a nivel de grupo de alelos se hizo mediante PCR seguido por un ensayo de hibridacion con sondas utilizando el kit de INNOLiPA HLA. Para evaluar la distribucion de las frecuencias alelicas, genotipicas y haplotipicas entre casos y controles se utilizo una prueba de x 2 o test exacto de Fisher. El equilibrio de Hardy-Weinberg se calculo con el software Genepop y la estimacion de los haplotipos con el software Arlequin. Las razones de odds y sus intervalos de confianza del 95% se estimaron con el paquete estadistico SPSS V20. Resultados El alelo HLA-A * 33 se asocio con riesgo para cancer cervical (OR = 4,84; IC95% 1,18–19,86) mientras que el HLA- B * 18 se asocio con proteccion (OR = 0,27; IC95% 0,07–1,01) al ajustar los modelos por lugar de nacimiento, edad y estatus de VPH. Conclusiones En la poblacion antioquena se observo mayor riesgo de cancer cervical asociado al alelo HLA-A * 33 y una disminucion de este riesgo asociado al alelo HLA-B * 18. Ambas asociaciones fueron estadisticamente significativas.