There’s two main types of termites: drywood termites, and subterranean termites.
Subterranean are true terrordome level termites, and can rabidly chew a structure to bits and need to be treated immediately. They can even chew through concrete if motivated enough. You will spot them usually in dark places in the attic, crawlspaces, floor joists, and they turn wood into muddy tubes. Thankfully they are relatively rare. But I have seen them in homes in the area.
Drywood are the ones everyone thinks when they think “termites”. They look like a longer, more clearly segmented ant. But you probably wont’ see them like that. What you will see are wings around windows and sinks , flying ones around sinks, little holes in the wall, and frass (termite poop) that looks like small round pieces of dirt.
Just because you’re seeing frass doesn’t mean they are alive. We have a lot of old homes here, and it’s really impossible to remove all the frass. You’ll need a pro to be for sure if they are active or not, but sometimes you can cover one of the holes in the wall for a while (say a minute or two ) then uncover it and look in the hole with a flashlight. Sometimes a termite will showup to figure out why the ventilation hole got plugged.
Drywood termites work slow and it takes years for them to threaten the structure. Usually, if you see a swarm, that is because they have already been present for a few years and the colony is large enough to produce a noticeable swarm. Don’t worry, this doesn’t mean your house is going to collapse.
Prevention options are limited and not entirely effective. In ground baits / traps / poison that surround the property are pretty good for subterranean but drywood can get past it. In wall pest spray also is pretty ineffective as they can and will find their way into the attic space first usually, and the in wall systems are usually a single thin line close to the bottom plate.
Spot treatments and “organics” are also pretty much a waste of time and money, with no guarantee that that is the only colony and that all the poison reached all the termites.
The best method for treatment is tenting with enough poison over a suitable time period to penetrate behind every wall and into every structural member. Even with that, once the tent is removed and the gas clears, you can technically have a brand new colony of termites move in next week as the poison does not linger.
This also means that most annual termite warranties you renew is probably a bad idea, as statistically by the time you pay that $300-$400 a year, even if you got drywood termites the next week after tenting it would be likely 3-4 years until they were actually able to be detected.
“Ok so I will make sure to buy a block home so I won’t have this problem!” you say.
Problem with that is that only the outside walls are concrete block. The furrier strips that the drywall attaches to the block is wood. The interior walls are framed with wood. Your cabinets are likely wood or wood composite. The trusses, beams, and planking that makes up the majority of your roof is also wood. So there’s plenty of food for these beasts. But again, unless it’s subterannean termites, drywood termites take quite a while to cause significant damage so don’t stress too much.
So what active things can you do to prevent termites?
Keep bushes and trees trimmed back away from the home. Do not have mulch close to or against the home. You can’t completely seal the attic to the outside as you need eave vents for ventilation and mold prevention, but close / seal any gaping openings to make bug entrance a little more difficult. Barrier sprays also aren’t entirely useless for general pest control. Termites are also attracted to light, so probably turn those off overnight. As a side benefit this will also knock down other bugs invading the insade of your home.