METHODOLOGY/PRINCIPAL FINDINGS: We used 13 nuclear microsatellite loci (on 911 individuals) and mitochondrial COI sequences to gain a better understanding of the historical and contemporary movements of Ae. albopictus in the Indo-Pacific region and to characterize its population structure. Approximate Bayesian computation (ABC) was employed to test competing historical routes of invasion of Ae. albopictus within the Southeast (SE) Asian/Australasian region. Our ABC results show that Ae. albopictus was most likely introduced to New Guinea via mainland Southeast Asia, before colonizing the Solomon Islands via either Papua New Guinea or SE Asia. The analysis also supported that the recent incursion into northern Australia's Torres Strait Islands was seeded chiefly from Indonesia. For the first time documented in this invasive species, we provide evidence of a recently colonized population (the Torres Strait Islands) that has undergone rapid temporal changes in its genetic makeup, which could be the result of genetic drift or represent a secondary invasion from an unknown source.
CONCLUSIONS/SIGNIFICANCE: There appears to be high spatial genetic structure and high gene flow between some geographically distant populations. The species' genetic structure in the region tends to favour a dispersal pattern driven mostly by human movements. Importantly, this study provides a more widespread sampling distribution of the species' native range, revealing more spatial population structure than previously shown. Additionally, we present the most probable invasion history of this species in the Australasian region using ABC analysis.
METHODS: This observational research used a spatiotemporal approach. We obtained CRS and rubella surveillance data from Dr. Sardjito Hospital, Provincial, and District Health Offices in Yogyakarta, Indonesia during January-April 2019. The home addresses of rubella and CRS cases were geocoded using the Global Positioning System. Average of the nearest neighbour and space-time permutation analyses were conducted to discover the spatiotemporal patterns and clusters of rubella and CRS cases.
RESULTS: The peak of rubella cases occurred in 2017 (IR: 22.3 per 100,000 population). Twelve confirmed cases of CRS were found in the 2016-2018 period (IR: 0.05 per 1,000 live births). The occurrence of CRS in Yogyakarta was detected 6-8 months after the increase and peak of rubella cases. The spatiotemporal analysis showed that rubella cases were mostly clustered, while CRS cases were distributed in a dispersed pattern. Rubella cases were found within a buffer zone of 2.5 km from any CRS case.
CONCLUSIONS: Rubella cases were spatiotemporally associated with the occurrence of CRS in Yogyakarta. We recommend strengthening the surveillance system of CRS and rubella cases in order to contain any further spreading of the disease.
METHODS: All enterovirus cases in Taiwan over almost ten years from three main databases, including national notifiable diseases surveillance, sentinel physician surveillance and laboratory surveillance programs from July 1, 1999 to December 31, 2008 were analyzed. The Pearson's correlation coefficient was applied for measuring the consistency of the trends in the cases between different surveillance systems. Cross correlation analysis in a time series model was applied for examining the capability to predict severe enterovirus infections. Poisson temporal, spatial and space-time scan statistics were used for identifying the most likely clusters of severe enterovirus outbreaks. The directional distribution method with two standard deviations of ellipse was applied to measure the size and the movement of the epidemic.
RESULTS: The secular trend showed that the number of severe EV cases peaked in 2008, and the number of mild EV cases was significantly correlated with that of severe ones occurring in the same week [r = 0.553, p spatio-temporal clusters in June 2008, the mild cases had begun to rise since May 2008, and the outbreak spread from south to north.
CONCLUSIONS: Local public health professionals can monitor the temporal and spatial trends plus spatio-temporal clusters and isolation rate of EV-71 in mild and severe EV cases in a community when virus transmission is high, to provide early warning signals and to prevent subsequent severe epidemics.
METHODOLOGY/PRINCIPAL FINDINGS: We conducted a one year longitudinal study of P. knowlesi vectors in three sites within an endemic area of Sabah, Malaysia. All mosquitoes were captured using human landing catch. Anopheles mosquitoes were dissected to determine, oocyst, sporozoites and parous rate. Anopheles balabacensis is confirmed as the primary vector of. P. knowlesi (using nested PCR) in Sabah for the first time. Vector densities were significantly higher and more seasonally variable in the village than forest or small scale farming site. However An. balabacensis survival and P. knowlesi infection rates were highest in forest and small scale farm sites. Anopheles balabacensis mostly bites humans outdoors in the early evening between 1800 to 2000 hrs.
CONCLUSIONS/SIGNIFICANCE: This study indicates transmission is unlikely to be prevented by bednets. This combined with its high vectorial capacity poses a threat to malaria elimination programmes within the region.