Some of us get bitten by mosquitos, more indoors than outdoors. Unless you’re a plumber, you may not be aware that there is a tiny swamp of standing water in the drains of your sink basins and shower stalls. (This S-trap, desaguadero en estilo-S; estilo ese) is designed to retain water as a plug while allowing spillage, locking septic gases below ground, yet still enabling drainage.) This liquid plug is an ideal hatchery, and needs to be screened or blocked to prevent those hatchlings from being deposited, and then biting and breeding indoors. But it’s easy, if you disrupt access to where they’re laying their eggs.
Go to a kitchen store, or maybe a plumbing supply, and get a mesh strainer, as shown above. Or simply cover the drains when not actually draining — with those handy lids that cap off your water garrafa arriving from e-pura or Cristal. For the floor drain in the shower, lids from those clear plastic containers of nuts sold at Costco are of a perfect size. (I’ve entered many articles on mosquito control, which can be searched in the white field at the upper right.)