You may think that a fly landing on your food is just a minor annoyance, but it could actually be a serious health hazard. Flies are not just annoying insects, they are also carriers of germs and diseases that can make you sick.
Flies have no teeth and can only eat liquid food. They use their mouthparts to spit digestive juices on solid food and turn it into a soup they can drink. “Flies don’t have teeth. They can’t take a bite out of our food, so they have to spit out some enzyme-rich saliva that dissolves the food, allowing them to suck up the resulting soup of regurgitated digestive fluids and partially dissolved food,” explains an article from The Conversation.
But that’s not all. Flies also regurgitate their food into bubbles to dry it out and fit more in their stomachs. They do this by evaporating some water from their food. This means that they are essentially vomiting on your food and then sucking it back up.
Flies can also taste food with their feet and groom themselves to clean their taste sensors. They use receptors on their feet to decide whether they’re on something nutritious. “As soon as they land, they use receptors on their feet to decide whether they’re on something nutritious,” says another article from The Conversation.
But where do flies come from? Flies are often found in rotting animal and plant waste, such as dead animals and faeces. They are commonly known as “filth flies” because of their association with these sources of pathogens and parasites. “They spend far more of their time in rotting animal and plant waste. Among this waste can be a range of pathogens and parasites,” warns the same article.
When flies land on your food, they can transfer these germs and diseases to your food. They transmit pathogens on their feet and body, as well as in their poop and vomit. Some of the diseases they can spread include cholera and typhoid, which can cause diarrhea, vomiting, fever and dehydration.
So how can you protect yourself from these nasty flies? The best way is to prevent them from landing on your food in the first place. You can do this by covering your food with lids or nets, keeping your kitchen clean and disposing of garbage properly. You can also use fly swats or traps to kill or catch them.
If a fly does land on your food, you may be tempted to just brush it off and eat it anyway. But this may not be a good idea. “While there is little doubt that flies can carry bacteria, viruses and parasites from waste to our food, a single touchdown is unlikely to trigger a chain reaction leading to illness for the average healthy person,” says the article from The University of Sydney. However, this may not be true for everyone. If you have a weak immune system or a chronic condition, you may be more susceptible to infections from flies.
Therefore, it is better to be safe than sorry and throw away any food that flies have landed on. You never know what germs they may have brought with them from their previous stops. Remember, flies are not just annoying, they are also dangerous. Don’t let them ruin your appetite or your health.
– Do flies really throw up on your food when they land on it?, The Conversation, November 8, 2021
– Should I throw away food once a fly has landed on it?, The University of Sydney, January 4, 2016
– Curious Kids: Do flies really throw up on your food when they land on it?, Florida International University, November 8, 2021
– Do Flies Throw Up On Our Food?, Seeker, August 23, 2014