While you may think a vacuumed floor and sanitised surfaces constitute a perfectly clean bedroom, think again.
There's a reason why cleaning is considered a chore - it can be boring, tedious, shudder-inducing and even a little soul-destroying (let's face it, the kitchen is clean for all of five minutes). While it's somewhat tolerable with a banging playlist and the prospect of a congratulatory gin, it's a necessary evil most adults begrudgingly endure.
Because of this, it can be easy to skip or 'overlook' certain areas - "I'll do it tomorrow", you lie, looking at that limescale on your glass shower.
But one area you really shouldn't be skipping is in your bedroom - it's even where you lay your head at night.
How can you sleep knowing that the pillowcase you washed a month ago is now crawling with bacteria?
Speaking to The Sun, a spokesperson for Online Bedrooms, a British furniture manufacturer, said spots like pillowcases and curtains are "silent killers" as they're often overlooked during the weekly spring-clean.
Pillowcases in particular are prone to bacteria, even if they appear to be clean.
"Even though they might look fresh and clean, they are hiding a range of nasty bacteria that could lead to enhanced allergies, unpleasant odours and skin issues," the spokesperson said.
"It's no secret that germs live all over our houses. However, there are lots of hidden spots that we may not ever think about during our cleaning rituals."
According to the experts, pillowcases can harbour more bacteria than a toilet seat in just one week. Think about it - you're resting your head on the slip for hours each night. Your hair in particular is likely slick with a delightful residue of styling products, dead skin cells and bodily oils, while the face can often be contaminated with residual makeup, oily skincare, sweat or the dirt and grime of the day (please for the love of God, wash your face).
Plus, if you're a drooler (guilty), you're probably going to have some saliva sullying those supposedly clean pillowslips.
On the positive side, this bacteria is likely nothing to worry about from a health-and-safety standpoint: "Luckily, the organisms found on pillowcases are largely harmless and are simply a build-up of skin cells, sweat and saliva," the spokesperson added.
To keep your pillowcases clean and pristine, experts recommend washing your bedding once a week.
The pillow isn't the only place that is secretly a breeding ground for bacteria. Mattresses can be magnets for grime, but when you bust out the hoover, they are frequently overlooked or ignored.
The older the mattress is, the more gross it's becoming, the spokesperson said. No one wants an unwanted visitor when they're trying to sleep, whether it be a pet, bug (or a drunk flatmate who accidentally mistakes your room for the bathroom), but an old and unclean mattress may mean there's a party of yeast and mould raging beneath you.
"As well as microbes, skin cells and food particles that are transferred to our mattresses from our bodies, a factor in making mattresses such a germ spot is gravity," they explained.
Any areas in close proximity to the bed, such as the bedside table or lampshade, can also be hotspots for dust and dirt - so make sure you're giving your room (that means all of it!) a wipe-down and vacuum weekly.