A maggot is the larva of a fly (order Diptera); it is applied in particular to the larvae of Brachycera flies, such as houseflies, cheese flies, and blowflies, rather than larvae of the Nematocera, such as mosquitoes and crane flies.

As with fleas and ticks, maggots can be a threat to household pets and livestock, especially sheep. Flies reproduce rapidly in the summer months, and maggots can come in large numbers, creating a maggot infestation and a high risk of myiasis (a maggot infestation of living tissue) in sheep and other animals. Humans are not immune to the feeding habits of maggots and can also contract myiasis. Interaction between humans and maggots usually occurs near garbage cans, dead animals, rotten food and other breeding grounds for maggots.

When maggots turn into adult flies and start the life cycle over, numbers will grow exponentially if unchecked, but disease, natural predators and parasites keep the population under control. Sealing garbage and using a garbage disposal or freezing rotting leftovers until waste collection day helps prevent infestation. Introducing an environmental control, such as Hister beetles, can also help reduce maggot populations.

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