Diversity of Anopheles species and zoonotic malaria vector of the Buton Utara Wildlife Sanctuary, Southeast Sulawesi, Indonesia.

BACKGROUND: The recent deforestation for agricultural, mining, and human re-settlement has significantly reduced the habitat of many non-human primates (NHPs) in Indonesia and intensifies interaction between the NHPs and humans and thus opening the possibility of pathogen spill-over. The emergence of zoonotic malaria, such as Plasmodium knowlesi, poses an immense threat to the current malaria control and elimination that aims for the global elimination of malaria by 2030. As malaria in humans and NHPs is transmitted by the female Anopheles mosquito, malaria vector control is very important to mitigate the spill-over of the malaria parasite to humans. The present study aims to explore the Anopheles species diversity in human settlements adjacent to the wildlife sanctuary forest in Buton Utara Regency, Southeast Sulawesi, Indonesia, and identify the species that potentially transmit the pathogen from monkey to human in the area. METHODS: Mosquito surveillance was conducted using larval and adult collection, and the collected mosquitoes were identified morphologically and molecularly using the barcoding markers, cytochrome oxidase subunit I (COI), and internal transcribed species 2 (ITS2) genes. Plasmodium sporozoite carriage was conducted on mosquitoes collected through human landing catch (HLC) and human-baited double net trap (HDNT). RESULTS: The results revealed several Anopheles species, such as Anopheles flavirostris (16.6%), Anopheles sulawesi (3.3%), Anopheles maculatus (3.3%), Anopheles koliensis (1.2%), and Anopheles vagus (0.4%). Molecular analysis of the sporozoite carriage using the primate-specific malaria primers identified An. sulawesi, a member of the Leucosphyrus group, carrying Plasmodium inui sporozoite. CONCLUSIONS: This study indicates that the transmission of zoonotic malaria in the area is possible and alerts to the need for mitigation efforts through a locally-tailored vector control intervention and NHPs habitat conservation.

A zoonotic human infection with simian malaria, Plasmodium knowlesi, in Central Kalimantan, Indonesia.

BACKGROUND: The Indonesian archipelago is endemic for malaria. Although Plasmodium falciparum and P. vivax are the most common causes for malaria cases, P. malariae and P. ovale are also present in certain regions. Zoonotic case of malaria had just became the attention of public health communities after the Serawak study in 2004. However, zoonotic case in Indonesia is still under reported; only one published report of knowlesi malaria in South Kalimantan in 2010. CASE PRESENTATION: A case of Plasmodium knowlesi infection in a worker from a charcoal mining company in Central Kalimantan, Indonesia was described. The worker suffered from fever following his visit to a lowland forest being cut and converted into a new mining location. CONCLUSION: This study confirmed a zoonotic infection using polymerase chain reaction amplification and Sanger sequencing of plasmodial DNA encoding the mitochondrial cytochrome c oxidase subunit I (mtCOI).

Flanged males have higher reproductive success in a completely wild orangutan population.

Male orangutans (Pongo spp.) exhibit bimaturism, an alternative reproductive tactic, with flanged and unflanged males displaying two distinct morphological and behavioral phenotypes. Flanged males are larger than unflanged males and display secondary sexual characteristics which unflanged males lack. The evolutionary explanation for alternative reproductive tactics in orangutans remains unclear because orangutan paternity studies to date have been from sites with ex-captive orangutans, provisioning via feeding stations and veterinary care, or that lack data on the identity of mothers. Here we demonstrate, using the first long-term paternity data from a site free of these limitations, that alternative reproductive tactics in orangutans are condition-dependent, not frequency-dependent. We found higher reproductive success by flanged males than by unflanged males, a pattern consistent with other Bornean orangutan (Pongo pygmaeus) paternity studies. Previous paternity studies disagree on the degree of male reproductive skew, but we found low reproductive skew among flanged males. We compare our findings and previous paternity studies from both Bornean and Sumatran orangutans (Pongo abelii) to understand why these differences exist, examining the possible roles of species differences, ecology, and human intervention. Additionally, we use long-term behavioral data to demonstrate that while flanged males can displace unflanged males in association with females, flanged males are unable to keep other males from associating with a female, and thus they are unable to completely mate guard females. Our results demonstrate that alternative reproductive tactics in Bornean orangutans are condition-dependent, supporting the understanding that the flanged male morph is indicative of good condition. Despite intense male-male competition and direct sexual coercion by males, female mate choice is effective in determining reproductive outcomes in this population of wild orangutans.

The potential for zoonotic malaria transmission in five areas of Indonesia inhabited by non-human primates.

BACKGROUND: Indonesia is home to many species of non-human primates (NHPs). Deforestation, which is still ongoing in Indonesia, has substantially reduced the habitat of NHPs in the republic. This has led to an intensification of interactions between NHPs and humans, which opens up the possibility of pathogen spillover. The aim of the present study was to determine the prevalence of malarial parasite infections in NHPs in five provinces of Indonesia in 2022. Species of the genus Anopheles that can potentially transmit malarial pathogens to humans were also investigated. METHODS: An epidemiological survey was conducted by capturing NHPs in traps installed in several localities in the five provinces, including in the surroundings of a wildlife sanctuary. Blood samples were drawn aseptically after the NHPs had been anesthetized; the animals were released after examination. Blood smears were prepared on glass slides, and dried blood spot tests on filter paper. Infections with Plasmodium spp. were determined morphologically from the blood smears, which were stained with Giemsa solution, and molecularly through polymerase chain reaction and DNA sequencing using rplU oligonucleotides. The NHPs were identified to species level by using the mitochondrial cytochrome c oxidase subunit I gene and the internal transcribed spacer 2 gene as barcoding DNA markers. Mosquito surveillance included the collection of larvae from breeding sites and that of adults through the human landing catch (HLC) method together with light traps. RESULTS: Analysis of the DNA extracted from the dried blood spot tests of the 110 captured NHPs revealed that 50% were positive for Plasmodium, namely Plasmodium cynomolgi, Plasmodium coatneyi, Plasmodium inui, Plasmodium knowlesi and Plasmodium sp. Prevalence determined by microscopic examination of the blood smears was 42%. Species of the primate genus Macaca and family Hylobatidae were identified by molecular analysis. The most common mosquito breeding sites were ditches, puddles and natural ponds. Some of the Anopheles letifer captured through HLC carried sporozoites of malaria parasites that can cause the disease in primates. CONCLUSIONS: The prevalence of malaria in the NHPs was high. Anopheles letifer, a potential vector of zoonotic malaria, was identified following its collection in Central Kalimantan by the HLC method. In sum, the potential for the transmission of zoonotic malaria in several regions of Indonesia is immense.

Significant increase in anti-SARS-CoV-2 antibodies after administration of heterologous mRNA-based vaccine booster in individuals receiving two doses of inactivated COVID-19 vaccine: A single-center study in healthcare workers in Jakarta, Indonesia.

BACKGROUND: Vaccine plays an important role in breaking SARS-CoV-2 transmission and accelerating the path to pandemic recovery. Currently, there is still limited data on heterologous COVID-19 booster vaccination efficacy and effectiveness in Indonesia. METHODS: Antibody response was retrospectively analyzed from 156 serum collected from healthcare workers that have received mRNA-1273 vaccine as the booster against SARS-CoV-2. These individuals had previously received the full two doses of inactivated anti-SARS-CoV-2 vaccine. Serological analysis was performed to measure total antibody, as well as IgA and IgG antibodies specific to spike (S) protein using ECLIA and ELISA methods. RESULTS: A significant increase in total, IgA, and IgG antibody titers was reported in vaccine receiving a third heterologous booster dose of mRNA-based COVID-19 vaccine following two doses of inactivated type. CONCLUSION: The third heterologous booster dose of vaccine may be beneficial to individuals with or without previous history of SARS-CoV-2 infection.

Prevalence and epidemiological characteristics of COVID-19 after one year of pandemic in Jakarta and neighbouring areas, Indonesia: A single center study.

We determined the prevalence and epidemiological characteristics of COVID-19 in Jakarta and neighboring areas, Indonesia from March 2020 to February 2021, based on nasopharyngeal/oropharyngeal (NP/OP) swab specimens that were tested at the Eijkman Institute for Molecular Biology, Jakarta. NP/OP swab specimens were collected from COVID-19 suspects or individuals in contact tracing programs from primary healthcare centers (PHC) and hospitals. The specimens were screened for the SARS-CoV-2 by qRT-PCR. Demography data and clinical symptoms were collected using national standardized laboratory form. Of 64,364 specimens, 10,130 (15.7%) were confirmed positive for SARS-CoV-2, with the peak prevalence of infection in March 2020 (26.3%) follow by in January 2021 (23.9%) and February 2021 (21.8%). We found that the positivity rate of the specimens from Jakarta, West Java, and Banten was 16.3%, 13.3%, and 16.8%, respectively. Positivity rate was higher in specimens from hospitals (16.9%) than PHC (9.4%). Of the positive specimens, 29.6% were from individuals aged >60 years old, followed by individuals aged 41-60 years old (24.2%). Among symptomatic cases of SARS-CoV-2, the most common symptoms were cough, fever, and a combination of both cough & fever. In conclusion, this study illustrates the prevalence and epidemiological characteristics from one COVID-19 diagnostic center in Jakarta and neighbouring areas in Indonesia.