Some problems related to insects (and other arthropods)
Although insects and other arthropods are tiny they are also countless. In the event of an environmental imbalance, following disturbances or poor management, populations of some arthropod species can outbreak and generate problems, often complex, requiring the intervention of experts.
Pest species of crops, foodstuffs, ...
Some species of arthropods can be crop pests. Although this problem is as old as agriculture (locust invasions), increased international trade and cropping conditions far from natural ecosystems increase the risks of new pests appearing or of resistance to conventional control methods.
In addition to agricultural production in the field or stored products, some arthropods can affect the solidity of constructions (termites) or the quality of food production or processing (contamination) or industrial production (dysfunctions).
Direct or indirect harm and disease vector
Arthropods can be vectors of pathogens responsible for diseases in humans, pets or stock animals: tsetse fly and sleeping sickness, anopheles and malaria, tiger mosquitoes and Chikungunya, ticks and Lyme disease, ...
Some species do not necessarily transmit diseases but are a direct source of harm to humans and animals through their repeated bites: mosquitoes, horseflies, bedbugs, etc. and sometimes even indirectly: allergies linked to dust mites.
Dangerous poisonous species
Poisonous arthropods can be dangerous to humans: stings, bites, itching; this dangerousness is increased by the risk of reaction to the venom in allergic subjects, in particular in the case of wasp or bee stings.
These species are globally rare in the world and there are currently no dangerous species in Réunion. This situation must be preserved by good management of imports and enhanced vigilance against the introduction of poisonous exotic species: discovery of an exotic scorpion and diagnosis of a very probable case of Recluse (spider) bite in recent years in Reunion).
Invasive alien species
Finally, invasive alien arthropods can be seriously harmful to ecosystems and native species, especially in island environments, and are at the origin of many known cases of biodiversity loss and even extinction of endemic species.
The impact of invasive species on native species results from direct action, through predation or parasitism, competition for food resources and habitats, but also indirectly by the existence of a shared natural enemy or the vector of diseases.