Background/Objectives: Oreganum vulgare essential oil (OEO) is safe, effective, multifunctional, and widely used. This study aimed to evaluate OEO’s chemical composition and antimicrobial activity in vitro against S. aureus and E. coli. Methods: The composition of OEO was determined by gas chromatography–mass spectrometry (GC-MS). Results: Compounds included monoterpenes with known antimicrobial activity, such as 2-menthen-1-ol (36.33%), linalyl acetate (9.26%), terpinene-4-ol (9.01%), 4-thujanol (6.33%), menthen (5.81%), sabinene (5.18%), and carvacrol methyl ether (5.14%). Conclusions: OEO had a strong antimicrobial activity with a minimum inhibitory concentration (MIC) of 1.90 mg/mL for S. aureus and 0.49 mg/mL for E. coli after 18 h incubation. The minimum bactericidal concentration (MBC) was 7.9 mg/mL against S. aureus and 0.99 mg/mL against E. coli. Thus, OEO could be used as a natural antimicrobial against S. aureus and E. coli infections.

Introducción. La resistencia de Plasmodium falciparum a diferentes fármacos antipalúdicos es un obstáculo para eliminar la enfermedad. El genotipo resistente de P. falciparum a la artemisinina puede evaluarse examinando los polimorfismos en el dominio de la hélice del gen Pfk13. La Organización Mundial de la Salud recomienda utilizar estas mutaciones como marcadores moleculares para detectar la resistencia a la artemisinina en países donde la malaria por P. falciparum es endémica.Objetivo. Identificar mutaciones relacionadas con la resistencia a artemisinina presentes en el dominio de la hélice del gen k13 de P. falciparum.Materiales y métodos. Mediante la detección pasiva de casos, se recolectaron 51 muestras positivas por microscopía para Plasmodium, provenientes de seis comunidades del distrito de Río Santiago en Condorcanqui, Amazonas. Se realizó la confirmación molecular de la especie mediante PCR en tiempo real y el dominio de la hélice del gen Pfk13 se amplificó y secuenció por electroforesis capilar. Las secuencias obtenidas se compararon con la cepa de referencia 3D7 de fenotipo silvestre.Resultados. Se confirmó un total de 51 muestras positivas para P. falciparum, provenientes de las comunidades de Ayambis, Chapiza, Palometa, Muchinguis, Alianza Progreso y Caterpiza. Después del alineamiento de las secuencias de ADN, se determinó que las muestras no presentaron mutaciones asociadas con resistencia en el gen K13. Discusión. Los resultados obtenidos son coherentes con estudios similares realizados en otros países de Sudamérica, incluyendo Perú. Estos datos proporcionan una línea base para la vigilancia molecular de resistencia a artemisinina en la región Amazonas y refuerzan la eficacia de la terapia combinada con artemisinina en esta área.

Background: The COVID-19 pandemic was associated with reported disruptions to healthcare delivery and malaria control activities in remote, malaria-endemic indigenous communities with limited access to healthcare. Remote indigenous communities in the Peruvian Amazon may have been especially vulnerable due to interruptions in malaria surveillance, diagnosis, and treatment. We investigated the impact of the COVID-19 pandemic on malaria burden, healthcare access, and community perceptions in hard-to-reach indigenous communities in the Amazonas region of Peru. In malaria-endemic regions, these lessons are particularly important because future health emergencies may similarly affect surveillance, diagnosis, prevention, and treatment activities, potentially reversing gains achieved through malaria control programs. Methods: A convergent parallel mixed-methods study was conducted in 2021 and 2022 across four indigenous communities in the Río Santiago district, Amazonas region, Peru. Quantitative data were collected through cross-sectional malaria surveys, and qualitative data were obtained through semi- structured interviews with inhabitants, community health workers, and local health personnel. Malaria infections were detected by microscopy and confirmed by PCR. Factors associated with the occurrence of malaria infection were studied based on a generalized estimating equation (GEE) approach applied to clustered binary outcome data and accounting for repeated observations within participants across study years. Qualitative data were analyzed thematically, and both components were integrated using the Pillar Integration Process framework. Results: A total of 514 participants were included. PCR-based malaria prevalence was 17.6% in 2021 and 26.09% in 2022. P. falciparum prevalence was particularly high in the Alianza Progreso community (2021: 24.19%, 2022: 16.16%) compared to the other studied communities. Previous malaria infection and chills were associated with PCR-confirmed malaria infection. Qualitative findings indicated that COVID-19-related disruptions affected malaria control activities by interrupting diagnosis and treatment availability, reducing community follow-up, and prioritizing COVID-19 response activities over malaria control. Participants also described fear of COVID-19, temporary migration to farm areas, and reliance on herbal medicine during the pandemic. Conclusions: The COVID-19 pandemic may have contributed to exacerbated pre-existing challenges to malaria control in remote indigenous communities in the Peruvian Amazon. Strengthening malaria surveillance, ensuring continuity of diagnosis and treatment, and improving healthcare access in geographically isolated communities will be critical to supporting malaria elimination efforts in Peru. Author summary: The COVID-19 pandemic disrupted essential health services worldwide, with potentially greater consequences for remote malaria-endemic communities with limited healthcare access. Indigenous populations in the Peruvian Amazon faced additional challenges due to interruptions in malaria surveillance, diagnosis, treatment, and control activities. We assessed the impact of the COVID-19 pandemic on malaria burden and healthcare access in four remote indigenous communities in the Amazonas region of Peru by combining malaria screening with interviews involving community members, community health workers, and healthcare personnel. Our findings showed persistent malaria transmission during the pandemic period, particularly in communities affected by Plasmodium falciparum . Participants reported reduced access to malaria diagnosis and treatment, fewer community follow-up activities, fear of attending health facilities, and changes in healthcare-seeking behaviors. These findings highlight how health emergencies can intensify existing barriers in geographically isolated populations and threaten malaria elimination efforts. Strengthening resilient health systems and ensuring continuity of essential malaria services during future crises will be critical to protect vulnerable communities in the Amazon region.

In South America, the arboviruses that are most noted are those that lead to dengue, Zika, and chikungunya. Nevertheless, there are additional arboviruses that trigger outbreaks, yet do not receive adequate attention, including Oropouche virus (OROV), Mayaro virus (MAYV), Saint Louis Encephalitis virus, Madariaga virus (MADV), and Rocío virus (ROCV). A rapid review was conducted using the databases PubMed, LILACS, Scopus, and Google Scholar. This analysis focused on studies that outline the clinical signs and diagnostic methods of neglected arboviruses impacting human populations in South America. A total of 38 studies met the inclusion criteria. Most reports focused on OROV and MAYV, whereas only a few studies described MADV and ROCV. Brazil accounted for the largest proportion of studies, followed by Peru. Across the reviewed literature, these arboviruses were associated with a broad clinical spectrum, ranging from non-specific febrile illness to severe neurological disease and congenital complications. Diagnostic approaches included serological assays, viral isolation or neutralization tests, and molecular methods such as RT-PCR. The increasing spread of these under-reported arboviruses in South America requires strengthening monitoring systems, optimizing access to specific diagnostics, and training healthcare personnel to identify these infections early and manage them appropriately.

BackgroundMalaria continues to pose a significant public health burden in Peru, where persistent limitations in diagnostic capacity remain a major concern. We evaluated a simplified molecular method combining boiling and Spin (B&S) for DNA extraction with and loop-mediated isothermal amplification with malachite green (MG-LAMP) for detection of Plasmodium sp.MethodsIn laboratory conditions, 50 positive (P. falciparum or P. vivax) and 50 negative samples confirmed by real-time PCR from inhabitants of the Río Santiago district, Amazonas, Peru, were tested with the B&S-MG-LAMP test. Subsequently, we screened 252 residents from malaria endemic communities of this area during 2024 as a field evaluation. Standard diagnostic performance indices, including sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) and the area under the ROC curve (AUC), were calculated using real-time PCR as the reference standard.ResultsB&S-MG-LAMP detected up to one Plasmodium sp parasite/μL (compared to 2.5 p/μL with real- time PCR). In the laboratory evaluation, it attained 100% sensitivity, specificity and a perfect agreement with PCR (kappa = 1) and an excellent diagnostic performance (ROC curve: AUC = 1.0). In the field evaluation, it attained a sensitivity of 100% and specificity of 99.15% for Plasmodium spp. and P. vivax, showing an excellent agreement with real-time PCR (Kappa = 0.92) and a high diagnostic accuracy (ROC curve: AUC = 99%). No positive cases of P. falciparum were detected in the evaluated samples, so no evaluation could be performed for this species.ConclusionsThe B&S-MG-LAMP test demonstrated an excellent diagnostic performance for malaria detection in this population. Our results support its potential as a deployable diagnostic alternative in areas with limited access to traditional laboratory infrastructure.