posted on 2022-08-12, 14:40authored byLetícia Recla, Mark Rheault, Kevin Golovin
Mosquito-borne diseases such as dengue, chikungunya,
and malaria
have long been a health and economic burden in our society. Such illnesses
develop after the pathogen, here arboviruses, are transmitted to humans
by female mosquitoes during blood meals. In the case of dengue and
chikungunya, such pathogens are transmitted to humans by infected Aedes aegypti females. Prior to feeding the insects
rest on vertical surfaces. In this work, a surface roughness threshold
was observed for live Aedes aegypti colonies, and below a root-mean-squared roughness of Sq < 0.124 μm the mosquitoes were physically incapable
of gripping vertical substrates. This roughness threshold was unaffected
by surface wettability or relative humidity. The importance of topographical
feature height was understood using a claw-hooking model considering
friction. Local defects above this threshold allowed claw hooking
to take place, emphasizing the importance of surface uniformity. An
antimosquito coating was developed that reduced surface roughness
below this threshold when it was applied to realistic surfaces such
as wood, brick, wall laminates, and tile. Lowering the surface roughness
below the threshold reduced the number of mosquitoes capable of landing
on the surfaces by 100%: i.e., no mosquitoes were able to adhere to
the treated surfaces. The ability to completely inhibit Aedes aegypti females from landing on surfaces represents
a new vector-borne disease control strategy that does not suffer from
the nontarget toxicity, resistance, or ecosystem disruption associated
with conventional chemical control strategies.