Aedes albopictus
In addition, some "Wolbachia" strains are able to directly reduce viral replication inside the insect. For dengue they include wAllbB and wMelPop with "Aedes aegypti", wMel with "Aedes albopictus". and "Aedes aegypti". A trial in an Australian city with 187,000 inhabitants plagued by dengue had no cases in four years, following introduction of mosquitoes infected with "Wolbachia". Earlier trials in much smaller areas had been carried out, but the effect in a larger area had not been tested. There did not appear to be any environmental ill-effects. The cost was A$15 per inhabitant, but it was hoped that it could be reduced to US$1 in poorer countries. The "strongest evidence yet" to support the "Wolbachia" technique was found in its first randomized controlled trial, conducted between 2016 and 2020 in Yogyakarta, an Indonesian city of about 400,000 inhabitants. In August 2020, the trial's Indonesian lead scientist Adi Utarini announced that the trial showed a 77% reduction in dengue cases compared to the control areas.