Do Fruit Flies Carry Disease?

Instructor: Stephanie Gorski

Steph has a PhD in Entomology and teaches college biology and ecology.

In this lesson, we'll learn a little about the habits of fruit flies and how to control them. We'll also discuss the ways in which fruit flies can be harmful - and the ways in which they cannot!

Eating Fruit flies

Have you ever eaten a bug? Sure you have! Insects are so pervasive that it's impossible to eliminate them entirely from our food. (And we probably wouldn't want to, since most of them won't hurt you and we'd have to dramatically increase our pesticide use to get anywhere close to that goal.) It's been estimated that you will accidentally consume about a pound of insects and insect parts over the course of your life.

One insect you have probably seen around your food is the fruit fly (a kind of fly, or Diptera). The common word 'fruit fly' refers to two different types of fly: Drosophilidae and Tephritidae. These flies are especially common in late summer or fall, but can occur any time of year.

Drosophila melanogaster, also known as the common fruit fly
Drosophila melanogaster, the common fruit fly

Fruit flies lay their eggs on ripened fruits or vegetables, as well as compost piles, dirty drains, and garbage disposals. The eggs are tiny, about ½ mm in length for Drosophilidae and about 1 mm for Tephritidae. Depending on the species, a female fruit fly can lay 500 eggs in her lifetime. It seems pretty likely that you may have eaten a fruit fly at some point in your life. So, will it hurt you?

Disease Vectors

Fruit flies don't sting or bite, so they can't do a lot to hurt you.

A disease vector is an organism that transmits diseases to humans. Some of the most famous disease vectors include mosquitoes, which transmit many diseases including malaria, and fleas, which transmit bubonic plague. Most disease vectors, you'll notice, are organisms that bite humans or otherwise interact with our blood. Fruit flies don't. So you'll be relieved, but not surprised, to learn that fruit flies don't transmit any known pathogens to humans.

Introducing Bacteria

Fruit flies can, however, carry bacteria - or create tiny wounds in fruit that allow bacteria to take hold. Adult female fruit flies create these little wounds in fruit with their ovipositor, or egg-laying organ, and then lay eggs inside the holes. These holes can serve as a place for bacteria and other microorganisms to gain a foothold in the fruit.

A recent paper suggested that a Tephritid fly, the Mediterranean fruit fly (Ceratitis capitata), could carry and transmit the disease-causing bacteria E. coli. So it is possible that fruit flies could transmit dangerous bacteria to your food.

To unlock this lesson you must be a Member.
Create your account

Register to view this lesson

Are you a student or a teacher?

Unlock Your Education

See for yourself why 30 million people use

Become a member and start learning now.
Become a Member  Back
What teachers are saying about
Try it risk-free for 30 days

Earning College Credit

Did you know… We have over 160 college courses that prepare you to earn credit by exam that is accepted by over 1,500 colleges and universities. You can test out of the first two years of college and save thousands off your degree. Anyone can earn credit-by-exam regardless of age or education level.

To learn more, visit our Earning Credit Page

Transferring credit to the school of your choice

Not sure what college you want to attend yet? has thousands of articles about every imaginable degree, area of study and career path that can help you find the school that's right for you.

Create an account to start this course today
Try it risk-free for 30 days!
Create An Account