Combining transinfected Wolbachia and a genetic sexing strain to control Aedes albopictus in laboratory-controlled conditions

The global expansion of Aedes albopictus has stimulated the development of
environmental-friendly methods aiming at controlling disease transmission
through the suppression of natural vector populations. Sterile male
release programs are currently being deployed worldwide, and are
challenged by the availability of an efficient sex separation that can be
achieved mechanically at the pupal stage and/or by artificial intelligence
at the adult stage, or through genetic sexing, which allows separating
males and females at an early development stage. In this study, we
combined the genetic sexing strain (GSS) previously established based on
the linkage of dieldrin resistance to the male locus with a Wolbachia
transinfected line. For this, we introduced either the wPip-I or the
wPip-IV strain from Culex pipiens in an
asymbiotic-Wolbachia-free Ae. albopictus line. We then measured
the penetrance of CI and life history traits of both transinfected lines,
selected the wPip-IV line, and combined it with the GSS. Population
suppression experiments demonstrated a 90% reduction in population size
and a 50% decrease in hatching rate. Presented results showed that such a
combination has a high potential in terms of vector control but also
highlighted associated fitness costs, which should be reduced before
large-scale field assay.