Leptospirosis represents a public health problem in Colombia. However, the underreporting of the disease is an unfortunate reality, with a clear trend towards a decrease in cases since 2019, when the guidelines for its confirmatory diagnosis changed with the requirement of two paired samples. The purpose of this review is to highlight the importance of leptospirosis. While the access to rapid diagnosis is available at practically all levels of care for dengue and malaria, leptospirosis—a doubly neglected disease—deserves recognition as a serious public health problem in Colombia. In this manner, it is proposed that molecular tests are a viable diagnostic alternative that can improve the targeted treatment of the patient and the timeliness of data and case reporting to SIVIGILA, and reduce the underreporting of the disease. Taking advantage of the strengthened technological infrastructure derived from the SARS-CoV-2 pandemic for molecular diagnosis in Colombia, with a network of 227 laboratories distributed throughout the national territory, with an installed capacity for PCR testing, it is proposed that molecular diagnosis can be used as an alternative for early diagnosis. This would allow case confirmation through the public health network in Colombia, and, together with the microagglutination (MAT) technique, the epidemiological surveillance of this disease in this country would be strengthened.

: 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.