I love when people who have clearly not had bedbugs link the Mark Rober video as if its the gold standard for eliminating bedbugs. There's good bits in there, but he doesn't tell the whole story and makes it seem like they're easy to get rid of, which is actual misinformation.
The methods discussed in that video only work if you catch them from day one or as preventative measures to not get them in the first place. Bedbug females can hold onto the materials they need to reproduce for weeks before they actually start laying eggs. Furthermore, bedbugs release a stress pheromone when their environment is upset that alerts other bedbugs in the area that they should run and hide. Once this happens, you are SOL as you just made your situation far, far, worse.
DE, steam, and heat are only viable as control methods, not elimination methods. Methods that kill on contact will only make the situation worse as you need to allow bedbugs to return to their hoarding to spread the exterminant around. That's why professionals use residual sprays to deal with them, not on-contact killers.
DE can and should be used alongside a professionally applied treatment, but you should never use it with the expectation that it alone will completely eliminate them. Bedbug nymphs are very similar to cockroaches in that they can squeeze into surfaces slightly larger than the human hair. If you see any bedbug regardless of life cycle stage, especially during the day, odds are you already have an infestation and should treat it as such.
I highly recommend working with a pest control company that uses Apprehend. Its a state of the art fungal insecticide that leaves a residual that survives for a minimum of three months after being sprayed and kills bedbugs within 24-48 hours of making contact with it. You can buy it online, but most people aren't going to go the lengths necessary to learn how to properly spray it or how to treat for bedbugs longterm, which is what you need to do.
Also, for those using DE: Rockwell makes an insecticide called Cimexa. Its 10x more effective than DE and can be used on baseboards, crevices, and other nook and crannies in your house or apartment. You can also mix it with water and it will leave a residual spray that is good for 30 days after treatment.
Bedbugs in each life cycle can live up to 18 months without a blood meal, but they require a full blood meal to molt to their next life cycle stage. When treating for them, you want to seal anything you suspect of being contaminated in an air-tight container and not disturb it for at least 18 months, otherwise you risk reintroducing them to your living situation and starting everything all over again. Anything you want to be able to use immediately, you can seal in an air-tight container with a Nuvan strip for a minimum of a day or heat treat it using a specialized heat treatment enclosure if the item in question is not heat sensitive.
If you suspect you have them, check your mattress (especially in seams or tufts) and box spring first and be on the lookout for obvious blood stains or black pepper like markings on your sheets. Those are obvious indicators of a possible bedbug infestation and are the first things an exterminator will look for other than moltings or live bugs.
In order of preference bedbugs prefer living in:
- wood
- fabrics
- metal/plastic
Wooden furniture in particular is extremely susceptible to them. Once they establish a foothold, its usually better to throw the furniture out then attempt to salvage it. Bedbugs can and will live in anything if it means not being exposed or otherwise easily detected. This includes electronics like TVs, computers, laptops, remote controls, amongst other common household items.
If you think you have them, most extermination companies will do a free consult if you call them or visit their website to setup an appointment.
Source: I lived in an infested apartment complex for three years before being able to move elsewhere. Obviously, I didn't know this before moving in or I would have looked elsewhere.
P.S. Most governments do not recognize bedbugs as anything more than a nuisance because they do not spread disease. In the US at least, we nearly had them eradicated in the late 80s before the EPA made the decision to ban heavy chemicals to treat them without offering any viable alternative. Private companies do not receive subsidies to treat them and due to their pervasive nature, once an infestation happens in a neighborhood or shared living arrangement, they spread very easily and make for very valuable repeat business. The best thing most people can do is educate themselves on the signs and proper response scenarios when they are detected. You want to approach them rationally. The natural response is to trigger a fight or flight scenario where you either go crazy trying to treat them yourself or you throw out all your furniture. Both approaches are wrong, and both approaches cause far more damage than good.