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The unprecedented global efforts for malaria elimination in the past decade have resulted in altered vectorial systems, vector behaviors, and bionomics. These changes combined with increasingly evident heterogeneities in malaria transmission require innovative vector control strategies in addition to the established practices of long-lasting insecticidal nets and indoor residual spraying. Integrated vector management will require focal and tailored vector control to achieve malaria elimination. This switch of emphasis from universal coverage to universal coverage plus additional interventions will be reliant on improved entomological monitoring and evaluation. In 2010, the National Institutes for Allergies and Infectious Diseases (NIAID) established a network of malaria research centers termed ICEMRs (International Centers for Excellence in Malaria Research) expressly to develop this evidence base in diverse malaria endemic settings. In this article, we contrast the differing ecology and transmission settings across the ICEMR study locations. In South America, Africa, and Asia, vector biologists are already dealing with many of the issues of pushing to elimination such as highly focal transmission, proportionate increase in the importance of outdoor and crepuscular biting, vector species complexity, and "sub patent" vector transmission., (© The American Society of Tropical Medicine and Hygiene.)

Dengue is the most prevalent arthropod-borne virus, with at least 40% of the world's population at risk of infection each year. In Australia, dengue is not endemic, but viremic travelers trigger outbreaks involving hundreds of cases. We compared the susceptibility of Aedes aegypti mosquitoes from two geographically isolated populations to two strains of dengue virus serotype 2. We found, interestingly, that mosquitoes from a city with no history of dengue were more susceptible to virus than mosquitoes from an outbreak-prone region, particularly with respect to one dengue strain. These findings suggest recent evolution of population-based differences in vector competence or different historical origins. Future genomic comparisons of these populations could reveal the genetic basis of vector competence and the relative role of selection and stochastic processes in shaping their differences. Lastly, we show the novel finding of a correlation between midgut dengue titer and titer in tissues colonized after dissemination.

Genomic DNA probes were made for two recently identified members of the Anopheles punctulatus complex; Anopheles sp. near punctulatus from Papua New Guinea and Anopheles farauti No. 7 from the Solomon Islands. The probes are species-specific and with the use of 32P labeling sensitive enough so that a squash blot of only a small segment of the mosquito is required for identification. The 119-basepair (bp) probe for An. sp. near punctulatus and the 1,106-bp probe for An. farauti No. 7 have been sequenced in full and the probes have been tested on field collected specimens. These probes now make it possible to distinguish An. sp. near punctulatus and An. farauti No. 7 from the other eight members of the An. punctulatus complex. A pan-species probe was also made from the 18S ribosomal DNA that binds to DNA from all members of the complex. These three probes complete the set required for distinguishing all known members of the An. punctulatus complex by DNA hybridization.

A method has been developed to identify the members of the Anopheles punctulatus complex using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Members of the An. punctulatus complex are the most important vectors of malaria in the southwest Pacific and consist of 10 cryptic species, An. farauti no. 1-7, An. punctulatus, An. sp. near punctulatus, and An. koliensis. For each species, PCR amplification of the ribosomal DNA internal transcribed spacer produced a 750-basepair product. Digestion with Msp I and electrophoresis on a 3.0% agarose gel results in banding patterns unique to each species. Isolates of the same species from different locations gave an identical pattern. The technique is sensitive enough so that a PCR-RFLP can be generated from as little as a single mosquito leg, allowing the rest of the mosquito to be used for other important epidemiologic analyses such as determining host feeding source, and for parasite detection.

Genomic DNA probes were made for five members of the Anopheles punctulatus complex of mosquitoes found in Papua New Guinea. Specific DNA probes were developed for An. punctulatus, An. koliensis, and three sibling species, An. farauti No. 4, An. farauti No. 5, and An. farauti No. 6, by differentially screening total genomic DNA libraries of individual species and sibling species with homologous DNA against heterologous DNA labeled with 32P. Probes ranged from 273 to 630 bp. Identification of species can be made from squash or dot blots using only a segment of the mosquito (i.e, head, thorax, abdomen, or even legs), allowing for concurrent analysis of the remainder of the mosquito for other epidemiologic characteristics.