Mosquito bites itch because some of the bug's saliva is injected into our skin. The saliva has anticoagulants that stop our blood from clotting, enabling the mosquito to feed freely. But these anticoagulants are foreign to the body, so our immune system releases histamines to counter them. This is when we feel itchy and uncomfortable because the histamines cause some blood vessels to expand and become leaky, helping white blood cells to get rid of the foreign anticoagulants.
However you look at it, this process is the same for all mosquito bites. But why do some people suspect that night bites are much harder to deal with? To put it simply, why do mosquito bites itch more at night? Is there a difference that we should know about?
There are simple reasons behind all that itching
The explanations for this phenomenon are simple. You see, it’s not that the bites are more irritating at night. It’s just that we do things at night that make the bites seem more irritating.
Get it? Don’t worry if you don’t because to understand this further, we’ve gathered the three major reasons that explain why mosquito bites tend to feel itchier during nighttime.
A lot of mosquitoes are more active at night
The answer is in the numbers. That’s right. The discomfort you’re feeling is not due to the bite’s intensity but to the sheer number of bites that you have – because most mosquitoes do more hunting at night.
Mosquitoes have an internal biological clock that tells them when it’s time to sleep and when it’s time to wake up, just like we humans do. According to a 1970s study published on the Journal of Experimental Biology, these insects have a group of nerve cells in their small nervous system that keeps track of time. These cells host a genetic “domino effect”. Once the first gene inside a nerve cell “turns on”, it causes a chain reaction for all the genes to turn on too, changing the behavior of the nerve cells and eventually the entire insect too.
This small process leads mosquitoes to have different levels of activity during an entire day. So some of them hunt when the sun is out while many prefer the cover of darkness. And for common house mosquitoes, the ones that mostly populate our homes, they are typically active at the night. That’s why it’s very likely that you’ll get more bites from them after the sun sets.
The heat from your blanket makes bites itch more
Another reason that might explain why bites feel itchier is your bed. Some theorize that when we sleep, thick covers and comforters heat up our bodies and increase our blood flow.
So when a mosquito bites your leg, for example, the anticoagulants in the mosquito’s saliva is re-distributed by the increased blood flow. This forces our body to produce more histamine, and it makes the bite seem more irritating that it usually is.
You just ‘think’ it’s itchier
Lastly, we have the simplest reason of all a mind-over-body situation.
Nighttime isn’t a popular time to be productive, so most of us use it to rest. This is when we’re not busy thinking about more important things. And since we’re not distracted by work and hobbies, simple discomforts like bug bites can drive us crazy.
The most typical scenario is when you’re asleep. When you’re dozing off, your mind is preoccupied by something else. But when you wake up abruptly because of a mosquito bite, your mind can sometimes think too much about the irritant and how you need to go back to sleep. This can feel overwhelming, and it leads you to think more about the bite and how much it itches.
So the next time you ask yourself; why do mosquito bites itch more at night? Think about these explanations. If there has to be something special about the bites that happen during the night, it’s got to be that we do different things during night time, compared to what happens during the day. And that’s why we think the bites between these times feel different.