Bed bugs are capable of traveling through an entire home, apartment building or hotel for a meal, so if you have an infestation, it's only a matter of time before both you and your partner become that meal. When an infestation begins, one partner may wake up with itchy, swollen bites, while the other may wake up without so much as a tiny red speck. Both partners don't have to experience bites for an infestation to be present.
Just like a journey of a thousand miles starts with a single step, an infestation of a thousand bed bugs starts with a single bug. If you have a brand-new or relatively small infestation, you may be the only food source the bed bugs need. If they've nested on your side of the bed and only have to travel to you for a meal, they could leave your partner alone.
Delayed or No Reaction
You may think you're the only one getting bitten, but your partner may simply have a delayed reaction to the bites, according to Michael F. Potter of the University of Kentucky College of Agriculture. A delayed reaction means that while you wake up with red bumps, your sleeping partner might not develop those bumps until a few days after he's bitten. You could also have a partner who doesn't have any reaction at all to bites and mistakenly thinks he's not getting bitten.
Different Manifestations and Locations
Bed bug bites typically look like small red dots or bumps, but if you're allergic to the bites, you could get welts and big raised, itchy bumps. Your sleeping partner who doesn't share the allergy may get bites so small, they're mistaken for acne, razor burn or a rash. Your partner may also have bites in places you didn't inspect, like the back of the neck or the lower back.
It's possible bed bugs just don't like other members of your family. Bed bugs commonly pick one person as their primary source of nutrition and ignore the other sleepers, according to USA Today. This preference might not have a reason behind it, or your sleeping partner may work with a chemical or use a certain body product that the bed bugs don't like.