Written by: A O’Neill, Licensed Pest Management Professional

What are bed bugs?

The common bed bug (Cimex lectularius) belongs to the Cimicidae family of blood-sucking insects and is responsible for the increase in infestations worldwide. 

These nocturnal pests truly are the stuff of nightmares as they prefer to feed solely on human blood, but if a human is unavailable, they will feed on the blood of other warm-blooded animals, including your pets. 

Bed bugs are ectoparasites, which means they don’t live on their host’s body. Once they’ve fed on you, they immediately crawl back to their harborage areas to digest their meal, mate, and the female will then lay her eggs.

The harborage areas are usually close to where you sleep, like the mattress, box spring, bed frame, and headboard.

adult bed bug with nymphs and shed skins
Reddish-brown adult bed bug in harborage area with nymphs, shed skins, and fecal spots

Bed bugs are resilient pests that have adapted to live wherever humans are and can cause a great deal of sleeplessness and emotional discomfort when you know you have them.

They are usually night-time feeders but will feed during the day if they are especially hungry.

Knowing what these pests are is all well and good, but it’s also just as important to know how bed bugs are spread and the main causes of them so you can avoid an infestation in your home, which we go into detail further down.

Are bed bugs visible to the human eye?

Although these bugs are small, they are visible if you see one or are looking for them. 

However, there are a lot of bugs that look similar to bed bugs and it’s not uncommon for people to mistake them for other insects, especially fleas.

I’ve been to lots of homes where the resident thinks they have a particular pest and it’s turned out to be bed bugs.  This is also a common occurrence reported throughout the pest control industry.

84% of pest control professionals were contacted about a pest, of which 71% thought they had fleas but it actually turned out to be bed bugs.[1] 

For that reason alone, it’s important to know what these critters look like so the infestation doesn’t get a chance to grow any bigger, and also so the cost of treatment doesn’t get any more expensive than it needs to be. 

The following gives you an idea of what bed bugs look like:

  • Bed bugs are flat (when unfed), oval-shaped, brownish-colored insects.
  • Despite having wing pads, they cannot fly, nor can they jump. They can only crawl.
  • Similar in shape and length to an apple pip with protruding eyes, six legs, and two antennae.
  • The adult grows to 5-7mm (3/16 inch) in length and when feeding its body swells up and lengthens up to 10mm (⅜ inch). It also becomes a darker brown/reddish color.
  • Baby bed bugs (nymphs) grow from 1mm – 4.5mm, and are semi-translucent, so are easily missed when looking for their hiding spots.

    When taking a blood meal, their abdomens become red in color, making them easier to see, as can be seen in the picture of a nymph feeding below.  As they mature they grow darker in color like the adults.
Almost translucent baby bed bug (nymph) feeding on human and abdomen red from blood meal
Credit: CDC/ Harvard University, http://phil.cdc.gov/phil, Public Domain, https://commons.wikimedia.org/w/index.php?curid=2119194

We have a whole page of pictures showing you EXACTLY what bed bugs look like throughout their lifecycle from eggs to adults, infestations, and the signs they leave behind.

As bed bugs are not seasonal pests, you’ll be able to see and find them all year round as they do not hibernate.  You might notice more bites (not everyone reacts to the bites) in the summer months though as they’re more active and reproduce more in warmer temperatures. 

On the other hand, if your home is kept between 70-80°F (21-26°C) and they have frequent access to a host, then they will continue to lay eggs and will not have to enter diapause, which is a dormant-like state allowing them to survive without frequent blood meals.

How big are bed bug eggs?

Bed bug eggs are tiny and it’s also important to know what they look like as the female will lay hundreds during her lifetime. 

She ensures they are well hidden in dark places like the bed frame, box spring, corners of the mattress, and on the seams, as well as in other upholstered furniture so they can hatch undisturbed adding to the growing infestation.   

  • Bed bug eggs are the size of a speck of dust – 1mm and are a pearly-white color.
  • Once hatched the nymphs grow up to 5mm in length and shed their skins 5 times before reaching adulthood as long as they are able to feed. They resemble the adults themselves, but are lighter in color and become darker as they mature.
Image of bed bug eggs close up hidden on cardboard
Cluster of bed bug eggs hidden on cardboard. Image credit: Dr. Harold Harlan/AFPMB (CC)

The body shape of both the adults and nymphs enables these parasites to crawl into very narrow crevices and find hiding spots when they are not feeding, this makes it harder to find where the eggs are.

Bed bugs can cause a great deal of stress and significantly impact your quality of life, because of this it’s vital you know what they look like and what their eggs look like so you can check and treat your home as soon as you see any evidence of them.

Where do bed bugs come from originally?

Bed bugs originally lived in caves and fed on the blood of the bats that lived in them.  But when humans started living in the same caves the bugs adapted to feed on human blood. These blood-suckers have lived alongside people for thousands of years. 

Their history of being a household pest has also been traced all the way back to ancient Egypt where archaeologists found fossilized bed bugs during an excavation. 

As civilization grew, so did infestations and before long these parasitic pests had spread throughout Europe and Asia. 

They were first recorded in England around 1583 and were soon aboard ships bound for America by explorers.

By the 18th Century, the common bed bug was prolific throughout North America where they thrived up to the 1950s when their numbers drastically reduced and they were no longer a common pest. 

Why?  DDT – a powerful insect killer that was used to exterminate cockroaches and other bugs.  DDT was sprayed in homes and it was so successful in killing bed bugs that they were all but eliminated.  Malathion was also another product that was successful in killing them. 

Why did bed bugs make a successful comeback?

There are several reasons for their resurgence since the 1990s.  One reason was the banned use of DDT because of its effects on wildlife. 

Other products have since come onto the market which bed bugs have grown resistant to. 

But another major factor for their come-back and how they are spread is through human activity, which is now the main cause of bed bugs, and this is covered next.

How do you get bed bugs in the first place?

As you know, bed bugs have lived alongside humans for thousands of years, and in more modern times they likely got their name from them living in your bed and biting and feeding when you’re asleep.

People often assume you only get bed bugs if your home is dirty.  This is untrue as bed bugs do not come from filth, they are not attracted to dirt or grim like other pests. 

If this were the case, then bed bugs would not be found in the most luxurious 5-star hotels.  These pests are primarily attracted to humans and feed on our blood as their food source.

Having said that, if you have lots of clutter in your home, then this gives them extra places to hide and breed, but it is not why you got bed bugs initially.

How do bed bugs spread so easily?

When people discover they have these pests, the question I and other pest technicians most often asked is ‘how did I get bed bugs?’  Well, there are lots of ways they get into your home, and three of the main causes are as follows:  

1. Travel

The most common way to get bed bugs is by staying in hotels, resorts, and similar types of overnight accommodation.   

The pest control industry reports that hotels are in the top three places where bed bugs are found, after single-family homes and condos/apartments.[2]

Your hotel can be spotlessly clean but it doesn’t mean it won’t have them. So, check your hotel room for bed bugs and carry out an inspection every time you stay in any overnight accommodation.

Bed bugs will crawl into your suitcases and bags and hide in your dirty clothes hitchhiking a ride back home with you where you’ll soon have your problem.

After all, it only takes one single pregnant female to start an infestation.

In fact, these pests can be found wherever humans are, such as on public transport, in retail stores, movie theatres, office buildings, schools, and so on.

2. Secondhand furniture

This is another common way that bed bugs get into your home as they love to hide in the seams of mattresses, box springs, and upholstered furniture like couches. They also can be found hiding in wooden furniture.

You might be surprised to know that you can even find them hiding in the spine of a book, so the next time you buy a second-hand book give it a check as you just never know.

Furthermore, if you buy any used furniture examine it for common signs of bed bugs which are black smears and blood spots, bed bug casings, and of course, live bed bugs.

Don’t isolate an infested item of furniture, as this won’t get rid of them because they can survive for months without a blood meal.

All this will do is spread them to other areas of your home, which is the last thing you want as it makes killing them so much harder once they start to spread.

Also, bed bug infestations can often be found in (furnished) rental properties as the property is not always thoroughly inspected for pests before being rented to new tenants.

This might be something to discuss with your landlord as a precaution before moving in.

3. Neighbors, guests, and friends

Maybe your neighbor in the apartment next door has bed bugs and they are finding their way into your home.

Try and find out if this is how you got bed bugs in the first place as this will impact whether you can get rid of them yourself.

For example, if your neighbor in the apartment next door has an infestation and the bugs are somehow finding their way into your apartment, it will not matter how many times you treat your home because they will continue to spread from their property until their infestation is treated.

A pest control company will be able to identify if this is the case.

Or, perhaps you had a guest or friend who has them stay or visit your home. This is another easy way that bed bugs are brought in because they can crawl out of the visitor’s (overnight) bag and then find their way onto your bed or furniture.

If you happen to be waking up with red marks or welts on areas of your body not covered when in bed then it might possibly be from bed bug bites.

People often don’t realize they have these bugs until they discover they are being bitten, so a thorough check of your bed area for signs will tell you if you’ve got them.

Other Ways Bed Bugs Are Spread

There are of course many other places from where you can bring bed bugs into your home, some of which you might find surprising, such as:

  • A friend or relative’s home
  • Place of work
  • Nursing homes
  • Schools, colleges, and universities
  • Cinema
  • Library
  • Federal buildings
  • Daycare homes and centers
  • Places of worship
  • Any form of public transport

Protecting your home from bed bugs

There are precautions to take that decrease the chances of taking bed bugs home with you, like keeping your purse on your lap and not on the ground in public areas, and putting all luggage in the bathtub in the hotel room while you carry out an inspection.

Other preventative measures can be taken, like installing mattress and box spring encasements which work by stopping the bed bugs already on your bed from escaping and biting you.

They also prevent any new bed bugs from infesting your bed.

An additional option is to install interceptor traps under each leg of furniture. You can monitor these on a regular basis to see if there are bed bugs in your home.

Now you know what bed bugs are and the many ways they can get into your home, it’s important to look out for any signs of them and keep these pests away.

If you find you’ve got bed bugs, I cannot stress how important it is that they are dealt with straight away as they can be incredibly hard to eradicate.

It’s always best to have a pest control company deal with them, but if you want to do your own pest control, then read how to permanently get rid of bed bugs but try and find out how you got them to start with so you don’t bring them back into your home.

[1] https://www.pestworld.org/news-hub/press-releases/pest-control-professionals-see-summer-spike-in-bed-bug-calls/ 

[2] https://www.pestworld.org/all-things-bed-bugs/bed-bug-facts-statistics/

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