Vector surveillance in high-rise buildings is important to predict and monitor the presence of vectors regarding their abundance and distribution. In this study, the infestation profile of Aedes aegypti and Aedes albopictus species in different environmental settings were investigated. Methods: Four high-rise apartments in four different localities were selected for ovitrap surveillance. Fifty ovitraps were placed in semi indoor and outdoor settings. Results: A total of 507 (42.8%) from ovitraps showed the presence of the Aedes species larvae. Out of these, 170 (33.5%) of the positive ovitraps were those placed in semi indoor and 337 (66.5%) in outdoor. Of the total 16,613 Aedes larvae found, 4,130 (24.9%) were from semi indoor, and 12,483 (75.1%) from outdoor. In terms of distribution, Ae. albopictus was predominantly found in outdoor environments (POI=87.5%; MLT=36.45 larvae). Ae. aegypti was also found in outdoor environments (POI=14.89%; MLT=8.26 larvae). There was a significant difference in POI for both Ae. aegypti and Ae. albopictus in the two different environments but no significant difference was observed in MLT, indicating that the density of the Aedes species in both environments was well distributed. Conclusion: In this study, the patterns of Aedes habitat in high-rise apartments were observed. This study has shown an invasion and adaptation of Aedes mosquitoes into the ecosystems of high-rise buildings. It can be concluded that housing designs and the condition of the surrounding environment affects the infestation profile and the distribution of Aedes mosquitoes.
Parasitic diseases represent one of the causes for significant global economic, environmental and public health impacts. The efficacy of currently available anti-parasitic drugs has been threatened by the emergence of single drug- or multidrug-resistant parasite populations, vector threats and high cost of drug development. Therefore, the discovery of more potent anti-parasitic drugs coming from medicinal plants such as Quercus infectoria is seen as a major approach to tackle the problem. A systematic review was conducted to assess the efficacy of Q. infectoria in treating parasitic diseases both in vitro and in vivo due to the lack of such reviews on the anti-parasitic activities of this plant. This review consisted of intensive searches from three databases including PubMed, Science Direct and Scopus. Articles were selected throughout the years, limited to English language and fully documented. A total of 454 potential articles were identified, but only four articles were accepted to be evaluated based on inclusion and exclusion criteria. Although there were insufficient pieces of evidence to account for the efficacy of Q. infectoria against the parasites, this plant appears to have anti-leishmanial, anti-blastocystis and anti-amoebic activities. More studies in vitro and in vivo are warranted to further validate the anti-parasitic efficacy of Q. infectoria.
Deforestation precipitates spillover of enzootic, vector-borne viruses into humans, but specific mechanisms for this effect have rarely been investigated. Expansion of oil palm cultivation is a major driver of deforestation. Here, we demonstrate that mosquito abundance decreased over ten stepwise distances from interior forest into conterminous palm plantations in Borneo. Diversity in interior plantation narrowed to one species, Aedes albopictus, a potential bridge vector for spillover of multiple viruses. A. albopictus was equally abundant across all distances in forests, forest-plantation edge, and plantations, while A. niveus, a known vector of sylvatic dengue virus, was found only in forests. A. albopictus collections were significantly female-biased in plantation but not in edge or forest. Our data reveal that the likelihood of encountering any mosquito is greater in interior forest and edge than plantation, while the likelihood of encountering A. albopictus is equivalent across the gradient sampled from interior plantation to interior forest.
Accurate identification of mosquitoes is crucial for the management and control of vector species. Although Singapore is a tropical country with high mosquito diversity, there are no identification keys specific to its mosquito fauna. An illustrated identification key to the genera of the adult female mosquitoes of Singapore is presented. Twenty genera are characterized and two genera found in Malaysia, Culiseta and Topomyia, are also included. The key will aid non-taxonomically trained operational officers in adult mosquito identification. The key to the genera provides the first crucial step in the process to species identification.
We explored and constructed haplotype network for simian malaria species: Plasmodium knowlesi, P. cynomolgi and P. inui aiming to understand the transmission dynamics between mosquitoes, humans and macaques. Mosquitoes were collected from villages in an area where zoonotic malaria is prevalent. PCR analysis confirmed Anopheles balabacensis as the main vector for macaque parasites, moreover nearly 60% of the mosquitoes harboured more than one Plasmodium species. Fragments of the A-type small subunit ribosomal RNA (SS rRNA) amplified from salivary gland sporozoites, and equivalent sequences obtained from GenBank were used to construct haplotype networks. The patterns were consistent with the presence of geographically distinct populations for P. inui and P. cynomolgi, and with three discrete P. knowlesi populations. This study provides a preliminary snapshot of the structure of these populations, that was insufficient to answer our aim. Thus, collection of parasites from their various hosts and over time, associated with a systematic analysis of a set of genetical loci is strongly advocated in order to obtain a clear picture of the parasite population and the flow between different hosts. This is important to devise measures that will minimise the risk of transmission to humans, because zoonotic malaria impedes malaria elimination.
Studies profiling community and zonal malaria entomological risk indices are required to identify high risk areas where targeted control resources are most needed or likely to have the greatest impact on reducing risk of malaria infection. This study presents a first report on malaria vector risk indices in two vegetation zones within Adamawa state, Nigeria. Endophilic mosquitoes were collected for one year in selected communities in the Guinea and Sudan savanna zones within the State. Plasmodium falciparum Sporozoite and human blood meal ELISA assays were carried out on the female Anopheles mosquitoes collected. Sibling species composition of the An. gambiae complex were determined using PCR assays. Mean numbers of mosquitoes in the Guinea savanna communities were significantly (t = 7.73, DF = 11, p < 0.001) higher than the Sudan. Man-biting rates (F = 2.76, p = 0.13) of Anopheles mosquitoes were higher in the Guinea but not significantly different from Sudan savanna. Sporozoite rates of mosquitoes within the Guinea savanna were 2.7 times higher than the Sudan. The predominant Anopheles coluzzii species encountered in the state had higher overall human blood indices (0.63) and sporozoite rates (6.9%) compared to An. gambiae (0.39, 1.9%) and An. arabiensis (0.58, 2.3%) respectively. Overall annual human blood indices (0.59) of mosquitoes in Adamawa were lower compared to reports from other States. Prevalence and higher transmission risks indices of endophilic An. coluzzii mosquitoes reveal the need for LLIN and management of relatively permanent An. coluzzii breeding sites in the State. Widespread cattle rearing lifestyle and lower human blood indices of mosquitoes in the study area suggest the need to investigate cattle blood indices of the mosquitoes in the state. Higher entomological risk indices in the Guinea Savanna zone provide baseline information for prioritization of malaria vector control supplies within the State.
A study was carried out from July 2001 until January 2003 in the Kinabatangan area of Sabah, part of Borneo island, where malaria used to be mesoendemic. Vector surveys determined that Plasmodium falciparum was the predominant species and Anopheles balabacensis the primary vector. Malaria cases have dropped drastically over the years but P. falciparum is still predominant. In the present study, Anopheles donaldi was the predominant species and was positive for sporozoites. Although An. balabacensis was present, none were infective. An. donaldi bite more outdoors than indoors and have a peak biting time from 18:00 to 19:00 h when most people are still out of their homes. An integrated malaria control programme along with area development has helped in the control of malaria and its vector.
Leptospirosis is an endemic disease in Malaysia and recently has received increasing attention mainly due to several recent incidents that have resulted in human mortality which have alarmed health professionals in Malaysia. The increasing incidence of leptospirosis in forested regions is associated with the bacteria infecting small wild mammals other than rats. Infection in wildlife could result in the introduction of new serovars to humans and domesticated animals. More research on leptospirosis and the screening of wildlife and humans near wildlife habitats is required to have a better understanding of the involvement of wildlife in the disease.
Total Variance (TV) and Generalized Variance (GV) are commonly used as a measure multivariate dispersion. However, these two statistics has some drawbacks. This paper proposes a new measure of multivariate dispersion, named Vectorial Variance (VV) an inner product for set of operators defined on a Hilbert-Smith space. Since, the exact sampling distribution of VV is difficult to find, therefore the asymptotic sampling distribution is obtained.
[Jumlah Varians dan Varians Teritlak kebiasaannya digunakan sebagai ukuran dispersi multivariate. Namun begitu, kedua-dua statistik ini mempunyai beberapa kelemahan. Dalam tulisan ini akan dicadankgan satu ukuran dispersi multivariate yang baru, dikenali sebagai varians bervektor (VV) yang merupakan suatu hasil darab terkedalam bagi set pengoperasi yang tertakrif ke atas suatu ruang Hilbert-Smith. Oleh kerana taburan pensampilan tepat dari statistik vv tersebut sangat sukar untuk ditentukan, maka taburan pensampilan asimtot telah diperolehi].
There has been progress towards malaria elimination in the last decade. In response, WHO launched the Global Technical Strategy (GTS), in which vector surveillance and control play important roles. Country experiences in the Eliminating Malaria Case Study Series were reviewed to identify success factors on the road to elimination using a cross-case study analytic approach.