BackgroundJapanese encephalitis has become a public health threat in Indonesia. Three genotypes have been recorded in Indonesia, i.e. genotype II (GII), genotype III (GIII) and genotype IV (GIV). Genotype I (GI) and genotype V (GV) have never been reported in Indonesia.ResultsA Japanese encephalitis virus (JEV) belonging to the genotype I-a (GI-a) has been isolated for the first time from a Culex gelidus mosquito in the Province of Jambi, Indonesia. This virus is related to a 1983 isolate from Thailand whereas the infected Cx. gelidus mosquito belonged to a Chinese haplotype.ConclusionsSurveillance of JEV and mosquito dissemination is recommended.

Forests are ecosystems that can support the existence of malaria vectors. The discovery of vector species in the forest environment will increase malaria transmission in the forest and its surroundings. The provinces of South Sumatra, Central Java, Central Sulawesi, and Papua are some of the provinces in Indonesia that still have forest ecosystems. The aim of the study was to know the diversity of Anopheles species and risk of malaria transmission in forest ecosystems in the provinces of South Sumatra, Central Java, Central Sulawesi, and Papua The sampling of mosquitoes was carried out by using the method of human landing collection, animal bited trap, around cattle collection, resting morning and light trap. Larva surveys are carried out in mosquito breeding place. Detection of plasmodium was done by Polymerase Chain Reaction (PCR) while blood feed analysis was carried out with a blood feed test using the Enzyme-linked immunosorbent assay (ELISA) method. Malaria vector species found in forest ecosystems in Central Java are Anopheles maculatus, Anopheles aconitus, Anopheles vagus, Anopheles balabacensis, and Anopheles subpictus. Malaria vector species in the forest ecosystem in South Sumatra are Anopheles nigerimus and Anopheles maculatus. Anopheles malaria vectors in forest environments in Central Sulawesi are Anopheles flavirostris, Anopheles barbirostris, Anopheles ludlowae, and Anopheles vagus. Anopheles malaria vectors in forest ecosystems in Papua are Anopheles farauti, Anopheles koliensis, Anopheles punctulatus, and Anopheles brancofti. Forest presence is at risk of malaria transmission in the provinces of Central Java, South Sumatra, South Sulawesi and Papua Abstrak Hutan merupakan ekosistem yang dapat mendukung keberadaan vektor malaria. Ditemukannya spesies vektor di lingkungan hutan akan meningkatkan penularan malaria di hutan dan sekitarnya. Provinsi Sumatera Selatan, Jawa Tengah, Sulawesi Tengah, dan Papua merupakan beberapa Provinsi di Indonesia yang masih memiliki ekosistem hutan. Tujuan penelitian adalah mengetahui keanekaragaman spesies Anopheles dan risiko penularan malaria pada ekosistem hutan di Provinsi Sumatera Selatan, Jawa Tengah, Sulawesi Tengah, dan Papua. Pengambilan sampel nyamuk dilakukan dengan menggunakan metode human landing collection, animal bited trap, around cattle collection, resting morning dan light trap. Deteksi plasmodium dilakukan dengan Polymerase Chain Reaction (PCR) sedangan analisa pakan darah dilakukan dengan uji pakan darah metode Enzyme- linked immunosorbent assay (ELISA). Survei jentik dilakukan di tempat-tempat perkembangbiakan nyamuk. Spesies vektor malaria yang ditemukan di ekosistem hutan di Jawa Tengah adalah Anopheles maculatus, Anopheles aconitus, Anopheles vagus, Anopheles balabacensis, dan Anopheles subpictus. Spesies vektor malaria di ekosistem hutan di Sumatera Selatan adalah Anopheles nigerimus dan An. maculatus. Anopheles vektor malaria di lingkungan hutan di Sulawesi Tengah adalah Anopheles flavirostris, Anopheles barbirostris, Anopheles ludlowae dan An. vagus. Anopheles vektor malaria pada ekosistem hutan di Papua adalah Anopheles farauti, Anopheles koliensis, Anopheles punctulatus, dan Anopheles brancofti. Keberadaan hutan berisiko terjadinya penularan malaria di Provinsi Jawa Tengah, Sumatera Selatan, Sulawesi Selatan, dan Papua.

Several methods exist to collect and assess the abundance of dengue vector mosquitoes, i.e., morning adult collection, pupal collection, ovitraps, human landing, and larval collection. Several of these methods are officially implemented to monitor mosquito density and make decisions on treatments for dengue control. This monitoring is also constrained by the need to conduct this assessment on a “one point/one day” process, meaning that once the threshold of 100 households is reached, the assessment is made, and the collectors teams move to another place, thus preventing the use of long-term sampling methods. This diversity of methods might be a source of variability and lack of statistical significance. There is also a lack of published data regarding the efficacy of these methods. Furthermore, the Stegomyia indices are shown to be not reliable for assessing the risk of dengue outbreaks. A mosquito survey was, thus, conducted in 39 locations corresponding to 15 dengue endemic provinces in Indonesia by using the different adult and larval collection methods recommended nationwide. A total of 44,675 mosquitoes were collected. The single larva method was the most efficient. Out of a total of 89 dengue-positive pools, the most frequently encountered virus was DENV2, which made up half of the positive samples, followed by DENV3 and DENV1, respectively. Factor analysis of mixed data showed that no correlation could be found between any methods and the presence of dengue virus in mosquitoes. Moreover, no correlation could be found between any methods and the incidence of dengue. There was no consistency in the efficacy of a given method from one site to another. There was no correlation between any of the parameters considered, i.e., method, incidence of dengue, location, and the presence of dengue virus in mosquitoes.

Currently, dengue has became a major public health problem in Indonesia. Aedes aegypti is confirmed as the main dengue vector. The organophosphate and phyretroid have been used in vector control program for more than 3 decades. Insecticide resistance evidences and mechanisms are essential to find the current status of insecticide susceptibility of dengue vectors. In this study, we analyzed the molecular principles of resistance to phyrethroid and organophosphate insecticides on mosquitoes collected from Palu, Central Sulawesi, and Belu and Ende, East Nusa Tenggara. Single-step polymerase chain reaction (PCR) method was conducted to detect amino acid mutations in paratype voltage-gated sodium channel (VGSC) gene and Achetylcoline esterase-1 (AChE) gene of Ae. Aegypti mosquitoes. The result showed that V1016G mutations of VGSC gene were detected from the wild-caught Ae. Aegypti mosquito from Palu, Belu and Ende. In contrast, G119 wild type allele of AChE gene was found from all Ae. Aegypti of all study sites. These evidences suggest that Ae. aegypti from Palu, Belu and Ende have developed multiple resistance towards phyrethroid insecticides. Based on prior susceptibility test, Ae. aegypti from all study sites were possibly developing resistance to organophosphate in other mechanisms. New strategies are needed, especially insecticide rotation in this area to achieve efficient vector control.

Chikungunya is repeatedly affecting Indonesia through successive outbreaks. The Asian genotype has been present in Asia since the late 1950s while the ECSA-IOL (East/Central/South Africa - Indian Ocean Lineage) genotype invaded Asia in 2005. In order to determine the extension of the circulation of the chikungunya virus (CHIKV) in Indonesia, mosquitoes were collected in 28 different sites from 12 Indonesian provinces in 2016-2017. The E1 subunit of the CHIKV envelope gene was sequenced while mosquitoes were genotyped using the mitochondrial cox1 (cytochrome C oxidase subunit 1) gene to determine whether a specific population was involved in the vectoring of CHIKV. A total of 37 CHIKV samples were found in 28 Aedes aegypti, 8 Aedes albopictus and 1 Aedes butleri out of 15,362 samples collected and tested. These viruses, like all Indonesian CHIKV since 2000, belonged to a genotype we propose to call the Asian-Pacific genotype. It also comprises the Yap isolates and viruses having emerged in Polynesia, the Caribbean and South America. They differ from the CHIKV of the Asian genotype found earlier in Indonesia indicating a replacement. These results raise the question of the mechanisms behind this fast and massive replacement.