Parasites: What are They?

Parasites are organisms that use us or another living thing to benefit themselves. You’re probably aware of parasites like bed bugs and fleas, but do you know how they feed off of humans and where they live? Find out here.

Different types of parasite

There are lots of different parasites and they come in all sorts of shapes and sizes. They can be separated into two groups based on how they use their hosts.

Obligate parasites

Obligate parasites are organisms that can’t complete its life cycle without using a host. That means that if they can’t find a host, they won’t be able to reproduce.

There are lots of obligate parasites in the form of viruses, bacteria and fungi.

Facultative parasite

A facultative parasite doesn’t rely on a host to survive or reproduce, but it still has parasitic behaviors. They are usually microorganisms and vegetation.

Insect parasites

Most of the parasites that affect us are insects. Here are a few of the common ones:

Bed bugs

Bed bugs live in mattresses and cracks in floors and walls, and rely on human blood to reproduce. They can be seen with the naked eye but are quite small.

They will often move through furniture and luggage to find a host, so it’s worth checking luggage after a trip and cleaning second-hand furniture before you use it.


Most commonly found on our pets, fleas feed off the blood of animals. They don’t have wings so can’t fly, but they are very quick. They can live up to 100 days, giving them plenty of time to reproduce.

Another common parasite

Plasmodium is a parasite, but it’s not actually a pest. It’s involved with a very common pest though, and it’s worth noting as it is harmful to humans.


Mosquitos carry the microorganism plasmodium, which causes malaria in humans. It lives inside the cells of the host, making it particularly difficult to treat. It has two hosts over its life – the mosquito, which it infects to find a host, then the human. The plasmodium transfers itself through the female mosquito’s saliva when it is feeding on a host.

There are so many different parasites across the UK, but these are the ones that affect humans the most. If you need a pest controller to come and remove any of these pests from your home, use our online form to get up to 4 quotes from reliable companies.

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Emily Rivers

Emily Rivers is the Customer Experience Manager at Quotatis. She informs customers of the latest developments in a range of products so they can make the best choice for their homes and ensures they get the best out of our service.