Mosquito repellents reduce human-vector contact of vector-borne diseases. We compared the repellent activity of 10 undiluted essential oils (anise, basil, bergamot, coriander, patchouli, peppermint, petitgrain, rosemary, sage and vetiver) against A. aegypti, A. dirus and C. quinquefasciatus using the arm-in-cage method. Petitgrain oil was the most effective against A. aegypti (270 min). Peppermint oil was the most effective against A. dirus (180 min). Interestingly, all single oils had attributes of repellency against C. quinquefasciatus (ranged, 120–360 min). Moreover, we integrated their binary combinations of highly effective essential oils against A. aegypti and A. dirus to potentially increase the protection time. A 1:1 combination of petitgrain/basil, petitgrain/coriander, basil/coriander and basil/sage reduced the median complete-protection time of 150 min for A. aegypti; a combination of sage and patchouli oils prolonged the median complete-protection time of 270 min for A. dirus. Combining essential oils effect protection time from these two mosquito species.

Mosquito-borne diseases, particularly dengue transmitted by Aedes aegypti, remain a major public health challenge, underscoring the urgent need for safe and effective plant-based repellents. We developed and evaluated a new lotion containing 15% w/w of a blend of citronella, patchouli, and sage essential oils, focusing on both skin safety and repellent efficacy. Skin compatibility was confirmed in 16 volunteers via patch testing at 30 min, 48 h, and 96 h post-application, with no irritation or allergic reactions observed. Repellent activity was assessed using the WHO-recommended Arm-in-Cage (AIC) method. The lotion achieved a mean complete protection time (CPT) of 103.13 ± 5.46 min and maintained > 90% protection over 3 h, with repellency rates of 100.0%, 99.41%, 94.19%, and 91.01% at 0, 1, 2, and 3 h, respectively. Across all volunteers, the mean repellency was 96.17 ± 0.81%, while biting rates remained below 14% at 3 h. These findings indicate that the essential-oil blend provides safe, sustained, and effective protection, supporting its potential as a natural alternative to synthetic repellents for personal protection against Ae. aegypti.

Objective: To disseminate the portable sequencer MinION in developing countries for the main purpose of battling infectious diseases, we found a consortium called Global Research Alliance in Infectious Diseases (GRAID). By holding and inviting researchers both from developed and developing countries, we aim to train the participants with MinION’s operations and foster a collaboration in infectious diseases researches. As a real-life example in which resources are limited, we describe here a result from a training course, a metagenomics analysis from two blood samples collected from a routine cattle surveillance in Kulan Progo District, Yogyakarta Province, Indonesia in 2019. Results: One of the samples was successfully sequenced with enough sequencing yield for further analysis. After depleting the reads mapped to host DNA, the remaining reads were shown to map to Theileria orientalis using BLAST and OneCodex. Although the reads were also mapped to Clostridium botulinum, those were found to be artifacts derived from the cow genome. An effort to construct a consensus sequence was successful using a reference-based approach with Pomoxis. Hence, we concluded that the asymptomatic cow might be infected with T. orientalis and showed the usefulness of sequencing technology, specifically the MinION platform, in a developing country.