Allan Iván Izaguirre González

Integrated One Health studies are essential for assessing the risks of leishmaniasis transmission. In Honduras, the most prevalent clinical presentation of leishmaniasis is the non-ulcerated cutaneous form caused by Leishmania infantum; however, research on its transmission dynamics remains limited. This study aimed to characterize the eco-epidemiology of leishmaniasis and identify potential zoonotic risk factors in the municipality of Ojos de Agua, Department of Comayagua, central Honduras, using a One Health approach. We collected sand flies using CDC light traps placed in intra- and peridomestic settings of households with a history of leishmaniasis. Concurrently, we evaluated domestic dogs and collected blood samples for serological and molecular testing. We also conducted active surveillance among community residents to identify human infections. We collected a total of 644 phlebotomine sand flies, including 186 females. We identified eight sandfly species, with Lutzomyia (Lutzomyia) longipalpis as the predominant species, followed by Pintomyia (Pifanomyia) evansi. Among the 64 engorged females screened, the overall PCR positivity rate for Leishmania spp. was 14.1% (9/64). Blood meal analysis of PCR-positive sand flies identified humans and pigs as blood and meal sources. Additionally, 18.6% (8/43) of domestic dogs were seropositive for Leishmania spp., and 23.3% (10/43) tested positive by PCR. DNA sequencing identified the infecting species as Leishmania infantum. We detected no active human cases during the study period. These findings highlight the value of a One Health approach for improving transmission risk monitoring in newly emerging areas with a history of ulcerative cutaneous leishmaniasis in Honduras.

Dengue is one of the most important arboviral diseases worldwide and is considered a reemerging infectious condition, posing a significant public health challenge, particularly among the pediatric population. The most effective diagnostic method during the acute phase of the illness (0–5 days), when viremia levels are high, is Reverse Transcriptase Polymerase Chain Reaction (RT-PCR). However, some molecular techniques may detect viral RNA for up to seven days, depending on the viral load. The objective of this study was to determine the efficacy of RT-PCR in detecting viral RNA after the fifth day of illness in pediatric patients at Hospital Escuela, Honduras. A total of 101 paired serum samples were analyzed, with positive results within the first five days, and a second sample from the same pediatric patients was obtained on day six or later. Among the referred patients, 76.2% (n=77) were clinically classified as having dengue with warning signs; the predominant serotype was DENV-3 in 90.0% (n=91). The mean Ct (cycle threshold) in samples collected within the first 0–5 days was 29.5, with 43.5% (n=44) showing Ct values between 25.1 and 32.0. Of the samples obtained on the 6th and 7th days, 82.2% (n=81) tested negative for viral RNA regardless of initial viremia; only 18.8% (19/101) tested positive, with a mean Ct of 34.2. These findings indicate that RTPCR had reduced efficacy in detecting dengue virus beyond the fifth day of illness. RT-PCR should be used preferably during the first five days of the disease, highlighting the need to integrate it with serology in later stages. KEY WORDS: Viral load; dengue fever; pediatrics; molecular virus detection; late-stage; diagnosis.

One Health is an integrated, unifying approach that aims to sustainably balance and optimize the health of people, animals and ecosystems. Observing the organizational format of the Group on Earth Observations (GEO) Health Community of Practice, the One Health Research Institute was created by Universidad Tecnológica Centroamericana in April 2024. This letter presents the first year of experience of a center that could represent a model research institution in the Americas region.