Gecko, a kind of lizard from the family Gekkonidae, residing in tropical regions of the world. Most of the people treat geckos as a kind of pest whilst others consider them harmless and rear them as pets.
Human aversion to the sight of geckos is the result of a number of reasons. They reproduce fast and easy, have long life span (usually years), always lose their tail and thereby create a mess, defecate all over the place, produce annoying chirping sounds, and, in a detrimental context, they possess salmonella which can cause typhoid fever, food poisoning and other illnesses. Geckos of the genus hemidactylus frentus in particular, often roam inside homes rather than wander about and dwell at the outside natural habitat; because of this, these geckos naturally become a nuisance to the householders.
On the contrary, some individuals find geckos visually appealing and take them in as house pets. Leopard geckos are among their favorites because, not only do they look strikingly beautiful, they are insectivorous as well; in a way, they keep your house clean and clear of other insects (they feed on mosquitoes, spiders and other small insects), which is a downside to ridding of geckos.
Since the cons of having geckos around outweigh the pros as mentioned above, it would be best to consider them pests.
There are no solid ways to getting rid of these pesky intruders. If you spray insecticide on them, it will just hold them off for a while before they return. In fact, they are fast enough to smell the chemical and flee before you can manage to spray on them. However, you can attempt the following methods (shared and experienced by many folks) as means of prevention to a certain degree but not as absolute resolutions:
(i) The most humane way is to spray them with water like using a water pistol, for a jet of water will render them immobile and fall from the wall they stuck to. Once they are motionless on the floor, sweep them out with a broom.
(ii) Glue board works too, same way that we use to constrain rats.
(iii) Mothball repels them. Throw lots of mothballs inside the house and in the garden to ward them off. Beware! Your house can smell like a giant cupboard if you overload it with too many mothballs.
(iv) Use a tea bag dipped in and moistened with citronella oil which is used as a traditional insect repellent. Geckos hate its substance and odor like mosquitoes repugning sandalwood.
(v) Seal all the crevices on the walls with glue papers in order to cut off their ingression.
(vi) Mixing bleach or Dettol with water can kill geckos.
(vii) Using a Vaseline-coated tub with cardboards for trapping geckos.
(viii) Lower the temperature in your house via air-conditioning because geckos are only able to adapt themselves to warm temperature.
(ix) Another way is to eliminate their source of food, i.e. other insects. By killing other insects with insecticides, the geckos will gradually leave your house once they run out of food supply.