Alejandra Pinto

Dr. Alejandra Pinto


Research Focus & Metrics

Academic Career Length

6Years (2021-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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4 November 2021 in Pathogens
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APAlejandra Pinto
Alejandra Pinto
OAOsman Archaga
Osman Archaga
ÁMÁngel Fernando Mejía
Ángel Fernando Mejía
LELenin Arturo Escober
Lenin Arturo Escober
JHJessica Henríquez
Jessica Henríquez
Gustavo FontechaGustavo Fontecha
Gustavo Fontecha
The countries of Central America and the island of Hispaniola have set the goal of eliminating malaria in less than a decade. Although efforts to reduce the malaria burden in the region have been successful, there has been an alarming increase in cases in the Nicaraguan Moskitia since 2014. The continuous decrease in cases between 2000 and 2014, followed by a rapid expansion from 2015 to the present, has generated a potential bottleneck effect in the populations of Plasmodium spp. Consequently, this study aimed to evaluate the genetic diversity of P. falciparum and the decrease in allelic richness in this population. The polymorphic regions of the pfmsp-1 and pfmsp-2 genes of patients with falciparum malaria from Honduras and Nicaragua were analyzed using nested PCR and sequencing. Most of the samples were classified into the K1 allelic subfamily of the pfmsp-1 gene and into the 3D7 subfamily of the pfmsp-2 gene. Despite the low genetic diversity found, more than half of the samples presented a polyclonal K1/RO33 haplotype. No sequence polymorphisms were found within each allelic subfamily. This study describes a notable decrease in the genetic diversity of P. falciparum in the Moskitia region after a bottleneck phenomenon. These results will be useful for future epidemiological investigations and the monitoring of malaria transmission in Central America.

11 May 2022 in Diagnostics
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Gustavo FontechaGustavo Fontecha
Gustavo Fontecha
Denis EscobarDenis Escobar
Denis Escobar
BRYAN ORTIZBRYAN ORTIZ
BRYAN ORTIZ
APAlejandra Pinto
Alejandra Pinto
DSDelmy Serrano
Delmy Serrano
HVHugo O. Valdivia,
Hugo O. Valdivia,
The diagnosis of malaria in Honduras is based mainly on microscopic observation of the parasite in thick smears or the detection of parasite antigens through rapid diagnostic tests when microscopy is not available. The specific treatment of the disease depends exclusively on the positive result of one of these tests. Given the low sensitivity of conventional methods, new diagnostic approaches are needed. This study evaluates the in-field performance of a device (Gazelle™) based on the detection of hemozoin. This was a double-blind study evaluating symptomatic individuals with suspected malaria in the department of Gracias a Dios, Honduras, using blood samples collected from 2021 to 2022. The diagnostic performance of Gazelle™ was compared with microscopy and nested 18ssr PCR as references. The sensitivity and specificity of Gazelle™ were 59.7% and 98.6%, respectively, while microscopy had a sensitivity of 64.9% and a specificity of 100%. The kappa index between microscopy and Gazelle™ was 0.9216 using microscopy as a reference. Both methods show similar effectiveness and predictive values. No statistical differences were observed between the results of the Gazelle™ compared to light microscopy (p = 0.6831). The turnaround time was shorter for Gazelle™ than for microscopy, but the cost per sample was slightly higher for Gazelle™. Gazelle™ showed more false-negative cases when infections were caused by Plasmodium falciparum compared to P. vivax. Conclusions: The sensitivity and specificity of Gazelle™ are comparable to microscopy. The simplicity and ease of use of the Gazelle™, the ability to run on batteries, and the immediacy of its results make it a valuable tool for malaria detection in the field. However, further development is required to differentiate Plasmodium species, especially in those regions requiring differentiated treatment.

27 June 2024 in Pathogens
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SBSharon Banegas
Sharon Banegas
Denis EscobarDenis Escobar
Denis Escobar
APAlejandra Pinto
Alejandra Pinto
MMMarcela Moncada
Marcela Moncada
GMGabriela Matamoros
Gabriela Matamoros
Gustavo FontechaGustavo Fontecha
Gustavo Fontecha
Background: Efforts on a global scale for combating malaria have achieved substantial progress over the past twenty years. Two Central American nations have accomplished their goal of eliminating malaria: El Salvador and Belize. Honduras has decreased the incidence of malaria and now reports fewer than 4000 malaria cases annually, aspiring to reach elimination by 2030. To accomplish this goal, it is essential to assess the existing strategies employed for malaria control and to address the task of incorporating novel intervention strategies to identify asymptomatic reservoirs. Methods: A survey for detecting asymptomatic cases was carried out in the community of Kaukira, in Gracias a Dios, Honduras, focusing on malaria transmission during 2023. Asymptomatic community members were recruited as participants, malaria screening was performed through a rapid diagnostic test in situ, and a blood sample was collected on filter paper. Highly sensitive molecular assays based on photo-induced electron transfer PCR (PET-PCR) were performed to detect the two species of Plasmodium circulating in Honduras: Plasmodium vivax and Plasmodium falciparum. In addition, the identification of the parasite species was verified by amplifying three genetic markers (Pvmsp3α, Pvmsp3ß, and Pfmsp1). Results: A total of 138 participants were recruited, mostly adult women. All individuals tested negative on the rapid diagnostic test. Positive results for malaria were detected by PET-PCR in 17 samples (12.3%). Most samples (12 out of 17) were amplified with a Ct value between 37 and 42, indicating very low parasitemias. Out of the 17 samples, 16 of them also showed amplification in the species assays. There were nine cases of P. falciparum infections and seven cases of P. vivax infections that were further confirmed by nested PCR (nPCR) of Pvmsp3 and Pfmsp1. Parasitemias ranged from 100 p/μL to less than 0.25 p/μL. One sample showed mixed infection. Conclusions: The existence of asymptomatic malaria reservoirs in Honduras can contribute to disease transmission and pose a challenge that may hinder elimination efforts, requiring public health authorities to modify surveillance strategies to identify the disease and treat this population accordingly.

6 February 2025 in ZooKeys
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Journal Article
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MHMauricio Hernandez
Mauricio Hernandez
MMMauricio Michel
Mauricio Michel
JGJoel Saamir García
Joel Saamir García
GDGeisy Dueñas
Geisy Dueñas
MMMarcela Moncada
Marcela Moncada
Gustavo FontechaGustavo Fontecha
Gustavo Fontecha
Bark beetles are among the primary drivers of tree mortality in coniferous forests worldwide. Individuals belonging to the order Coleoptera were identified across different forest areas in Honduras. Descriptive statistics were used to calculate the number of families, subfamilies, genera, and species collected per department. Moreover, the barcoding approach was used by amplifying and sequencing the mitochondrial COI gene. The intraspecific genetic diversity of Ips apache was also analyzed. 1,131 individuals were examined and 27 genera were identified. Most of the specimens were identified as belonging to the genus Ips, accounting for 53.2% of the total. Xyleborus accounted for 16.5% and Temnoscheila accounted for 10%. Fewer than four individuals were found for fifteen genera. 68% of the specimens were identified to the species level, and all the specimens were identified to the genus level. Ips, Temnoscheila, Xyleborus, Hypothenemus, and Pityophthorus exhibited the most extensive geographic distribution among the sampled sites. At the genus level, Olancho, El Paraíso, and Copán displayed the highest diversity. This study also marks the first report of the genera Xylomeira and Stephanopachys in Honduran pine forests. Within I. apache, evidence of intraspecific genetic diversity was observed, although no population structure was detected. While this research provides an updated inventory of beetle species associated with Honduran coniferous forests, further taxonomic surveys and ecological studies are essential to better understand the spread and impact of bark beetles in pine ecosystems.

Verified
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Gustavo FontechaGustavo Fontecha
Gustavo Fontecha
Denis EscobarDenis Escobar
Denis Escobar
BRYAN ORTIZBRYAN ORTIZ
BRYAN ORTIZ
APAlejandra Pinto
Alejandra Pinto
The elimination of malaria requires strengthening diagnosis and offering adequate and timely treatment. Imported cases of falciparum malaria represent a major challenge for pre-elimination areas, such as Central America, where chloroquine and primaquine continue to be used as first-line treatment. The pfs47 gene has been previously described as a precise molecular marker to track the geographic origin of the parasite. The aim of this study was to design a simple and low-cost technique using the polymorphic region of pfs47 to assess the geographic origin of P. falciparum strains. A PCR-RFLP technique was developed and evaluated using the MseI enzyme that proved capable of discriminating, with reasonable precision, the geographical origin of the parasites. This method could be used by national surveillance laboratories and malaria elimination programs in countries such as Honduras and Nicaragua in cases of malaria where an origin outside the Central American isthmus is suspected.

Verified
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AMAshley Melissa
Ashley Melissa
KJKevin Gabriel Euceda Jiménez
Kevin Gabriel Euceda Jiménez
APAlejandra Pinto
Alejandra Pinto
HVHugo O. Valdivia,
Hugo O. Valdivia,
LCLesly Chaver
Lesly Chaver
Gustavo FontechaGustavo Fontecha
Gustavo Fontecha
As Honduras approaches malaria elimination, imported infections pose a growing challenge to disease surveillance and control. In this study, we analyzed 14 molecular markers—six from Plasmodium falciparum and eight from P. vivax—in samples from local and migrant subjects to assess their utility in differentiating local versus imported infections. All P. falciparum isolates carried the wild-type pfcrt haplotype associated with chloroquine susceptibility. However, polymorphisms in pfmdr1, pfama1, pfglurp, and pfs47 revealed distinct genotypes in migrant versus local samples, suggesting external origins. For P. vivax, three novel pvcsp VK210 haplotypes and the first detection of a VK247 variant in Honduras were identified in migrants. Additional novel haplotypes were found in pvmsp1, pvmsp3α, pvmsp3β, pvs47, and pvs48/45. Several of these markers—particularly pfmdr1, pfs47, pvs47, and pvs48/45—proved informative for inferring geographic origin. This study demonstrates the value of molecular surveillance in low-transmission settings, supporting public health efforts by identifying potentially imported cases.