Without a doubt, fruit flies are terrible pests around the world. Female fruit flies lay their eggs inside the ripening fruit, and those eggs will later evolve into adults. Once the eggs hatch, the larvae will be accompanied by bacteria that cause the fruit to rot. Once this happens, you can no longer eat the fruit or sell it at the market.
But can fruit flies make you sick? Fruit flies can somehow make you sick through ingestion of food contaminated or using eating utensils that had contact with bacteria associated with fruit flies. Fortunately, there are no reported deaths caused by fruit flies.
Fruit flies live in overripen, rotten fruits and love to reside in garbage cans, plumbing leaks, and wastewater systems. These smart pests can also follow you as you go home and even enter your house without your knowledge. More questions arising from these are: Do fruit flies carry some organisms that produce infectious diseases? How sick can you be? And how can you get sick? Keep on reading to learn more!
How Can You Identify Fruit Flies?
Scientifically known as “Drosophila melanogaster,” also called vinegar flies, fruit flies are about 1/8 inch long (2 to 4 mm) and are obviously smaller than houseflies. They usually have bright red eyes, a light yellowish-brown to the dark brown cylindrical body, and a long, hairy antenna. Also, their abdomen is usually darker than their thorax.
Aside from decaying fruits and vegetables, you can also find them in dirty tables and kitchen utensils, especially those with food residues and cleaning materials such as sponges and rags. They also love fermenting liquids such as vinegar, fruit juice, wine, and beer, so don’t be surprised to see them in bottles and cans.
Life Cycle of Fruit Flies
First of all, you should understand that fruit flies punch the skin of a fruit, and the female fruit flies lay about 20 eggs inside the fruit. About 24 hours later, these eggs will hatch into larvae. Also called maggots, the larvae are usually 2.5 – 4.5-mm long and carry bacteria that cause the fruit to rot and fall from the tree prematurely.
Once the fruit falls to the ground, the mature larvae will leave the rotting fruit and will move to a colder place, such as under the soil, where it will undergo the pupa stage. During this time, the larvae will stay inside a cocoon for about 6 days until it becomes an adult. After two days, the adult fruit fly is now ready to mate.
Can Fruit Flies Survive in the Winter?
Fruit flies are present in any kind of weather, but they are more active in warmer months. They will not die in the winter, but their reproduction rate will be lower. Researches show that their lifespan decreases once the temperature is 60°F. Consequently, they will stop developing once the temperature is below 53°F.
Do Fruit Flies Bite Human?
Fruit flies love ripening fruits, sugary and fermented liquids, all rotten or decaying matter regardless if they are food or not.
Note, however, that fruit flies don’t feed on blood. In fact, they don’t have biting mouthparts. So technically speaking, they don’t sting nor bite people. Also, they don’t eat animal feces or dead insects.
How Can Fruit Flies Follow You at Home?
As a smart buyer, you will make sure that the fruits are fresh and that there are no fruit flies on them. But once you arrive home, you’ll be shocked seeing that the fruits already had fruit flies on them. So how can that be possible? Well, fruit flies have a sensitive smell and are very attracted to fruits.
Fruit flies are also excellent flyers, which is why they can follow you as you go home. Believe it or not, an adult fruit fly can fly to as far as 9 miles (14.5 kilometers) on a single journey! They beat their light wings about 200 times per second. Amazingly, they can also rotate 90° in less than 50 milliseconds!
How Can Fruit Flies Enter Your House Without Your Knowledge?
Fruit flies can grow from 3 to 4 mm in length. With their very small size, they can easily enter your house without you knowing. All they need are tiny openings such as damaged window screens and small gaps once you open or close the door.
Fruit flies can also pass through kitchen sinks, leaky roofs, floor drains, urinal areas, wall cracks, and even attics. These are also some of their favorite places inside a house to breed.
Interestingly, both males and females are polygamous, which makes them faster to reproduce. So don’t be surprised if you’ll see lots of fruit flies flying inside your house one day, especially in the kitchen.
How Can Fruit Flies Make You Sick?
Fruit flies can only make you sick if any of the following will happen:
- You accidentally ate the rotten fruit where the larvae of fruit fly had left some bacteria.
- Your trash can is always left open, and it has been infested by fruit flies. Then, you ate the fruit that had been infested by the same batch of fruit flies.
- Using kitchenware and utensils that were not properly cleaned, and fruit flies have stayed on them for quite some time.
- Fruit flies can potentially contaminate sterile surfaces, particularly in clinics and hospitals.
What Kind of Diseases Fruit Flies Can Give You?
Unlike house flies, fruit flies don’t bring any life-threatening diseases to humans simply because they are “cleanlier” pests. However, eating fruits that had fruit flies may cause vomiting, diarrhea, stomach upset, and intestinal myiasis. In worst cases, you may suffer from food poisoning and may be hospitalized for a few days.
Likewise, some reports said that the bacteria from fruit flies might carry serious diseases such as listeria, E. coli, and salmonella. But again, no official records prove that this is true. Also, it is very unlikely that a person will intentionally eat rotten fruits or any decaying food.
What Will Happen if You Eat Fruit Fly Eggs?
Whether you accidentally or intentionally eat fruit fly eggs, they will simply die. Fortunately, nothing will happen to you. As mentioned earlier, it is the larvae that carry the bacteria, and not the eggs. However, eating those eggs is very disgusting. This is also why you should be very careful before eating anything.
Why Should You Get Rid of Fruit Flies?
Fruit flies may not cause you serious diseases, but it doesn’t necessarily mean you should not get rid of them. The fact that you can potentially get sick is already a valid reason to eliminate them. Aside from that, these nuisance pests destroy your fruits and can therefore cause waste of your hard-earned money.
Likewise, fruit flies can cause a great loss of profit if you are selling fruits or have a fruit garden. Several incidents in many parts of the world resulted in losses of millions of dollars due to fruit fly infestations. No wonder most pest companies have been investing a lot in improving their products.
How to Control Fruit Flies and Prevent Them From Coming Back?
There are a lot of ways of controlling fruit flies, but so far, the best way is proper sanitation. This includes eliminating the sources of attraction for these pests, such as sealing the garbage cans and hiding your fruits. In some cases, you can make special traps so they won’t be able to enter your house.
You may use some insecticides to kill these insects and totally eradicate their nests. However, this method is quite dangerous, especially if you have small children, the elderly, or people with asthma. Therefore, you would want to consult a professional exterminator before dealing with toxic chemicals inside your home.
In general, fruit flies cannot transmit deadly diseases and therefore are not really dangerous to humans. In fact, they have been beneficial to scientists in terms of genetic research and other complex studies. However, they are still pests, and you should get rid of them as early as possible.
List of Sources
Merchant, M. (2016). Indoor Flies and Their Control. Texas A&M AgriLife Extension.
Jacob, S. B. (2013). Vinegar Flies. PennState Extension.
Fruit Flies. (2021). University of Maryland Extension.
Potter, M. F. (1994). Fruit Flies. University of Kentucky.