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Since Aedes albopictus was discovered in 2011 in the San Gabriel Valley it has become widespread despite the "harsh" environmental conditions and intense efforts to control or eliminate it. Species introduced into a new area may survive, thrive, or disappear depending on whether its new environment is suitable. The San Gabriel Valley Mosquito and Vector Control District expended considerable resources from 2011 to 2015 to eradicate this invasive species or, at a minimum, control and manage its spread. Despite the intense effort, the distribution of Ae. albopictus steadily expanded. Over those 5 years this increase shifted from a geometric to exponential pattern. What enabled Ae. albopictus to survive initially, become established, and then expand their distribution when ecological conditions in southern California were considered hostile for this invasive species? This study explores several biological characteristics including skip oviposition, installment egg hatching, and variable larval development that may have helped Ae. albopictus flourish in its new environment.

In southern California, ocular infections caused by Onchocerca lupi were diagnosed in 3 dogs (1 in 2006, 2 in 2012). The infectious agent was confirmed through morphologic analysis of fixed parasites in tissues and by PCR and sequencing of amplicons derived from 2 mitochondrially encoded genes and 1 nuclear-encoded gene. A nested PCR based on the sequence of the cytochrome oxidase subunit 1 gene of the parasite was developed and used to screen Simulium black flies collected from southern California for O. lupi DNA. Six (2.8%; 95% CI 0.6%-5.0%) of 213 black flies contained O. lupi DNA. Partial mitochondrial16S rRNA gene sequences from the infected flies matched sequences derived from black fly larvae cytotaxonomically identified as Simulium tribulatum. These data implicate S. tribulatum flies as a putative vector for O. lupi in southern California.