Francisco Javier Diaz

Introduction. Monkeypox cases have persisted in Colombia since the 2022 outbreak.Objective. To report the isolation and characterization of a monkeypox virus (MPXV) strain obtained from a Colombian patient during the 2022 outbreak, and to evaluate the antiviral potential of repurposed drugs against this isolate.Materials and methods. Lesion samples were inoculated into Vero-E6 cells. Viral isolation was characterized using virologic and molecular techniques. In addition, indirect immunofluorescence and neutralization assays were performed using convalescent serum. The antiviral activity of heparin, chloroquine, and ciprofloxacin was evaluated using a combined treatment strategy (multiplicity of infection = 2). Results. Cytopathic effect was observed 48 h post-infection. Viral titers reached 1.50 × 10⁶ PFU/ml. Phylogenetic analysis placed the isolate within clade IIb (B.1 lineage). Convalescent serum remained IFI-positive up to 1:160, and a 50% plaque reduction neutralization test of 35.6 was obtained. Chloroquine (50% inhibitory concentration ≈ 51.1 μM; selectivity index ≈ 2.2), heparin (50% inhibitory concentration ≈ 45.6 μg/ml; selectivity index ≈ 2.4), ciprofloxacin (50% inhibitory concentration ≈ 48.9 μM; selectivity index ≈ 3.9), and rifampicin (positive control; 50% inhibitory concentration ≈ 14.3 μM; selectivity index ≈ 19.7) significantly reduced MPXV infection. Molecular docking showed favorable binding of ciprofloxacin (-7.0 kcal/mol) and rifampicin (-7.2 kcal/mol) to the viral polymerase.Discussion. We successfully isolated and characterized an MPXV strain from a Colombian patient, establishing a platform for humoral and antiviral testing. Chloroquine, heparin, and ciprofloxacin showed measurable in vitro activity, supporting their potential for repurposing against this disease.

Introduction Colombia’s tropical climate and low-altitude cities create an ideal environment where mosquito-borne diseases can thrive. During 2013-2014, dengue was the most diagnosed cause of febrile syndrome. However, other viruses like Venezuelan equine encephalitis (VEEV), Mayaro (MAYV), and chikungunya viruses (CHIKV) were also present, and their true prevalence was likely underestimated due to limited surveillance. Methods We conducted a cross-sectional study involving 90 febrile patients from the Urabá region. For each patient, we collected both acute and convalescent serum samples, which were analyzed to detect antibodies against VEEV, CHIKV, and MAYV. Additionally, we attempted virus isolation from the acute-phase serum samples. Results We found that antibodies against VEEV were present in 28.3% of samples, CHIKV antibodies were detected in 5%, and MAYV antibodies in 1.7%. Notably, one patient tested positive for CHIKV even before the first outbreak was recognized in Colombia in 2014. Furthermore, we isolated and fully sequenced VEEV, and our analysis revealed a close phylogenetic relationship with subtype ID Panamanian strains. Conclusion This study highlights the need to consider arboviruses beyond just dengue (DENV), when evaluating febrile illness in Colombia. The detection of VEEV and CHIKV, even before they were officially recognized as significant public health threats in this region, underscores the need for enhanced surveillance and diagnostic capabilities.

: Acute undifferentiated febrile illness (AUFI) is the main cause of medical attention in the tropics worldwide. Malaria, arboviral diseases, and leptospirosis are the most important etiologies. These are highly endemic in the Urabá antioqueño, Colombia, being the main causes of fever in several municipalities in this region. However, up-to-date data regarding the infecting species and serotypes are lacking. Thus, we characterized the etiology of AUFI, focusing on malaria, arboviruses, and leptospirosis in this region and the circulating infecting species. An active surveillance was conducted between January and April 2022, and July and October 2023 in two local hospitals in the Urabá antioqueño. Febrile patients were enrolled voluntarily. Malaria, arboviral diseases, and leptospirosis were screened through direct, serological, molecular, and rapid diagnostic methods. Amplicons obtained for dengue virus (DENV) and Leptospira spp. were analyzed through phylogenetic analysis. A total of 184 febrile patients were enrolled. A confirmed etiology was detected in 43.4% of patients from Apartadó and 61.2% from Turbo. Malaria was the most frequent cause in both municipalities, which was caused mainly by Plasmodium falciparum in Apartadó and Plasmodium vivax in Turbo. Dengue virus serotype 1 genotype V, DENV genotype Asian-American, and DENV genotype Cosmopolitan were identified, as well as pathogenic Leptospira species closely related to Leptospira santarosai and Leptospira noguchii. The present study confirms the importance of malaria, dengue fever, and leptospirosis in the Urabá antioqueño. Plasmodium falciparum and P. vivax were identified, as well as two DENV serotypes and three DENV genotypes and two different Leptospira species.

Objective: The objective is to compare the clinical, virological, and immunological characteristics of people living with HIV‐1 who were treated with first‐line integrase inhibitors (INSTIs) versus those treated with other antiretrovirals. Methods: This is a descriptive observational, retrospective, two‐center study. We selected individuals who began antiretroviral therapy (ART) within the first year of diagnosis and who had received at least 1 year of treatment. Their therapy consisted of two nucleoside/nucleotide reverse transcriptase inhibitors, along with a third medication (INSTI, nonnucleoside reverse transcriptase inhibitor (NNRTI), or protease inhibitor). The primary comparison was between individuals who initiated ART containing INSTIs and those who initiated ART containing NNRTIs or protease inhibitors. We evaluated clinical outcomes, residual viral load, circulating proviral DNA, inflammation, and cardiovascular risk markers, T cell count and phenotype, and the frequency of HIV‐specific T cells. Results: Individuals who received INSTI‐based regimens started treatment at a more advanced disease stage and had a significantly shorter ART duration at study inclusion than individuals who did not receive INSTI‐based ART. Individuals receiving INSTIs achieved CD4 ⁺ T cell counts at levels comparable to those within the non‐INSTI group, as well as similar levels of virological, immunological, and cardiovascular markers. Nonetheless, those in the INSTI‐based group had higher CD8 ⁺ T cell counts and lower CD4/CD8 ratios, as well as lower high‐density lipoprotein levels. Conclusions: INSTI‐based regimens offer benefits to Colombian people living with HIV‐1, who are starting ART, including improved and faster virological and CD4 ⁺ T cell reconstitution. This occurs despite treatment initiation for advanced disease.

Background: Morbillivirus canis is the etiological agent of a highly contagious disease that affects diverse domestic and wild animals. Vaccination is considered the most suitable strategy for controlling CDV dissemination, transmission, and distemper disease. However, the emergence of new CDV strains has led to the need to update the current vaccine strategies employed to prevent CDV infection in domestic and wild animals. Currently, there is a lack of effective alternatives for wild animals. Diverse computational tools, especially peptide-based therapies, enable the development of new universal vaccines. Objective: The aim of this study was to evaluate the safety and humoral and cellular immune response of a new generation of vaccines based on CDV peptides as single-peptide mixtures or multiepitope CDV polypeptides in mice. Methods: Twenty-four BALB/c mice were subjected to a three-dose regimen for 28 days. Seroconversion was evaluated via ELISA, and cellular immune responses were evaluated via flow cytometry through activation-induced markers (AIMs). Results: Compared with the placebo, the peptide mixture and multiepitope CDV polypeptide were safe, and seroconversion was statistically significant in the multiepitope CDV polypeptide and commercial vaccine (CV) groups. The numbers of antigen-specific CD4+CD134+ and IFN-γ+ T cells, CD8+ T cells and TNF-α- and IL-6-producing cells were greater in the mice immunized with the multiepitope CDV polypeptide than in the control mice. Conclusion: This combined approach represents a potential step forward in developing new immunization candidates or enhancing current commercial vaccines to control CDV disease in domestic dogs and wild animals.

Introduction: Acute undifferentiated febrile illnesses (AUFIs) impose a large burden in the tropics. Understanding of AUFI’s epidemiology is limited. Insufficient diagnostic capacity hinders the detection of outbreaks. The lack of interconnection in healthcare systems hinders timely response. We describe a protocol to study the epidemiology and aetiologies of AUFI and pathogen discovery in strategic areas of Latin America (LA).Methods and analysis: Global Infectious Diseases Network investigators comprising institutions in Colombia, Dominican Republic, México, Perú and the USA, developed a common cohort study protocol. The primary objective is to determine the aetiologies of AUFI at healthcare facilities in high-risk areas. Data collection and laboratory testing for viral, bacterial and parasitic agents are performed in rural and urban healthcare facilities and partner laboratories. Centralised laboratory and data management cores deploy diagnostic tests and data management tools. Subjects >6 years with fever for Leptospiraspp, andRickettsiaspp. Serum is used for viral cultures and next-generation sequencing for pathogen discovery. Analysis includes variable distributions, risk factors and regression models. Laboratory results are shared with health authorities and network members.Ethics and dissemination: The protocol was approved by local ethics committees and health authorities. The results will be published in peer-reviewed journals. All study results are shared with local and regional health authorities.

Bovine leukemia virus (BLV) is a retrovirus that primarily infects dairy cows. Although few studies have also used the tax gene, phylogenetic studies of BLV use mostly the env gene. The aim of this work was to establish the circulating genotypes of BLV in specialized dairy cattle from Antioquia, Colombia. Twenty blood samples from Holstein Friesian cows were collected, and their DNA was isolated. A PCR was performed for a partial region of the env and tax genes. A phylogenetic analysis was carried out using the maximum likelihood and Bayesian methods for both genes. Nineteen sequences were identified as genotype 1 by env and tax genes. Only one sequence was clustered with genotype 3 and had the highest proportion of different nucleotide sites compared to other strains. Four amino acid substitutions in the 134 amino acid residue fragment of the Env protein were identified in the Colombian sequences, and three new amino acid substitutions were reported in the 296 amino acid residue fragment of the Tax protein. R43K (Z finger), A185T (Activation domain), and L105F changes were identified in the genotype 3 sample. This genotype has been reported in the United States, Japan, Korea, and Mexico, but so far, not in Colombia. The country has a high rate of imported live animals, semen, and embryos, especially from the United States. Although it is necessary to evaluate samples from other regions of the country, the current results indicate the presence of two BLV genotypes in specialized dairy herds.

The human immunodeficiency virus type 1 (HIV-1) reservoir, composed of cells harboring the latent, integrated virus, is not eliminated by antiretroviral therapy. It therefore represents a significant barrier to curing the infection. The biology of HIV-1 reservoirs, the mechanisms of their persistence, and effective strategies for their eradication are not entirely understood. Here, we review the molecular mechanisms by which HIV-1 reservoirs develop, the cells and compartments where the latent virus resides, and advancements in curative therapeutic strategies. We first introduce statistics and relevant data on HIV-1 infection, aspects of pathogenesis, the role of antiretroviral therapy, and the general features of the latent HIV reservoir. Then, the article is built on three main pillars: The molecular mechanisms related to latency, the different strategies for targeting the reservoir to obtain a cure, and the current progress in immunotherapy to counteract said reservoirs. Graphical Abstract

Introduction: It has been shown that the transmission of SARS-CoV-2 occurs mainly by air, and the risk of infection is greater in closed spaces.Objective: To describe the epidemiology, virology and molecular characterization of a COVID-19 outbreak at a closed vaccination point during the third wave of SARS-CoV-2 in Colombia.Materials and methods: Diagnostic tests, interviews, sampling, cell cultures and viral sequencing were carried out, the latter being molecular characterization and lineage identification.Results: Seven workers were positive for SARS-CoV-2; among these, 3 samples were analyzed, plus an additional sample belonging to the mother of the presumed indexcase; all samples were identified with lineage B.1.625, with a maximum of 2 nucleotides difference between them.Conclusions: Variant B.1.625 was identified as the cause of the COVID-19 outbreak, and a co-worker was also identified as the index case. Unexpectedly, attending a vaccination day became a risk factor for acquiring the infection.

Entre finales de 2019 y mediados de 2022, la pandemia de COVID-19 ha causado más de 600 millones de casos confirmados y al menos 6,5 millones de muertes, constituyendo la emergencia de salud pública más importante de las últimas décadas. En paralelo con el transcurso de la pandemia, ha tenido lugar una carrera sin precedentes por la obtención de vacunas eficaces para el control de la rápida dispersión del virus. Cuatro meses después del anuncio de la emergencia del SARS-CoV-2, agente de la pandemia, ya habían 115 “vacunas candidatas”, cinco de ellas en fase de ensayos clínicos.