Ants aren't thought to carry disease, but as you never know where they have been, you don't really want them marching through your home.
Read more on ants and how to go about tackling an ant problem.
Ants – Order Hymenoptera
Ants, wasps and bees are all part of the same order – Hymenoptera. All have a common denominator of a narrow waist although this is not quite as obvious in bees.
There are many types of ants. Mostly seen in a domestic environment is the Common Black Ant, Garden Ant. Other ants that can be found indoors are The Ghost Ant, Pharaoh’s Ant, Argentine Ant. These ants have a more complicated life cycle so treatment and surveys have to be thorough to eradicate the problem.
A new colony will begin with a newly mated female digging a hole in earth/sand then laying a small number of eggs. After 3-4 weeks these hatch to produce legless grubs which the female feeds from secretions from her salivary glands. When these grubs are large enough after about 3 weeks they pupate for 2 weeks then adult ants emerge , and these will be workers whose sole role will be to keep the nest clear from debris including, pupa cases, guard duties and foraying for food. They will eat small insects, nectar, seeds and the sugary solutions from green and black fly which ants milk from the flies and in return they are protected from other predatory insects. During the Spring and Summer nests grow as the queen (fertile females) ability to lay eggs increases. Some of the later generations will be fertile males and female eggs. These will eventually hatch and emerge from the nest on warm humid days. Males and female winged ants will emerge at about the same time of day, usually in the afternoon from many, many nests. The males and females mate and the males will die as their purpose has been completed. The newly emerged and mated females will then chew off his wings and will burrow underground to start a new nest.
This can take the form of sprays, poisoned baits and dusts. Professionally applied insecticides will be stronger than DIY bought sprays etc. whose active life will be shorter than professionally sourced and supplied products.
If you have an ant problem, I am happy to provide advice to help prevent ants entering properties and deter activity in kitchen areas and other rooms.