Head lice are (arguably) the most common parasite you'll encounter in the US. The US Centers for Disease Control (CDC) says anywhere from 6 to 12 million children are affected annually, and kids aged 3 to 11 are the most common victims. The good news is that head lice aren't known to spread diseases.

Head lice live on human scalps only. You cannot get them or spread them via pets. An adult louse is about the size of a sesame seed, and it can be gray, tan or nearly black. We share them through head-to-head contact, by sharing clothing and hats and making contact with bedding, furniture or automobile interiors.

To tackle an infestation, you should:

• Treat infected family members with over-the-counter products, and follow the directions closely
• Use a nitcomb thoroughly and frequently on the entire family for a few weeks
• Wash all clothing and bedding in hot water and dry them on high heat
• Vacuum all furniture and carpets well

If you have items that cannot be washed but are possibly infested, like a sports helmet, place them in a plastic bag outdoors for two weeks. Adult lice must feast on your blood daily to survive, but the eggs (called "nits") can survive for ten days more before hatching.

Short hair is easier to manage during a lice situation, and a quick "buzz cut" can be beneficial. Hair dye will also kill head lice and repel them, so if you love your long hair, this is an ideal time to color it.

Body lice are distinct from pubic lice. We'll cover them shortly.

Body lice are specialists. They live on human skin and can spread diseases, per CDC. They're not very common in the US yet, but you might pick them up while traveling overseas or by sleeping in an infested bed at a hotel, hostel or Airbnb.

The first symptom of a body lice infestation is itchy, rashy skin. You should see a doctor for treatment. Overall, the cure is similar to that of head lice. Use the prescription or over-the-counter products thoughtfully, wash your clothing and bedding in hot water and dry them on high heat, and vacuum your furniture thoroughly. See your physician again if you can't get rid of the rash. It might be something else, like scabies.

Pubic lice, or "crabs," are specialists, too. They like the coarse hairs of your pubic areas, but they can also get cozy in your armpits, beard and eyebrows. They look like tiny crabs, thus the nickname.

If you suspect pubic lice, see a doctor or visit a clinic. They'll provide you with treatments and directions for use.

Public lice are usually spread through sexual contact. After a diagnosis, clean your home well, wash all the bedding and clothes in hot water and dry them on high heat, and complete your course of treatment. Avoid intercourse for a few weeks.

Now, let's move on to bed bugs.

CDC says, "Bed bugs (Cimex lectularius) are small, flat, parasitic insects that feed solely on [human and animal blood] and while they sleep. [They're] reddish-brown in color, wingless, range from 1mm to 7mm... and can live several months without a blood meal."

Historically, bed bugs were a problem in developing countries, but they've spread rapidly in parts of the US, Canada, the UK and Europe. Bed bugs are found in five-star hotels and resorts, and the cleanliness of the living conditions does not determine their presence.

The easiest way to identify a bed bug infestation is by the tell-tale bite marks on your neck, arms, face, hands or other body parts. However, these bite marks may take 14 days to develop, so look for other clues.

You're looking for:

• Presence of bed bugs in the sheets or seams of a mattress
• The presence of their exoskeletons in your bedding
• Rusty–colored blood spots on your bedding
• And a sweet, musty odor in your bed

Insecticides commonly treat bed bug infestations. It's not enough to wash your bedding. If you suspect that you have an infestation, contact a professional pest company or cleanup crew. Then visit your physician for topical creams to soothe your skin.

The good news is that, unlike our caveman ancestors, all these parasites can be managed. You cannot control the fact that you picked up a parasite, but you can control the outbreak and eliminate them. Clean well, buy and use the right products, and seek professional help.

Still, there are plenty of living conditions that may make it challenging to tackle parasites. And sometimes, our most cherished family members have difficulty managing parasites like lice and bed bugs. Seniors living alone, for example, might struggle to keep up with the cleaning and product regimen, particularly if they have ambulatory issues (trouble walking) or dementia. They'll need extra help during this time.

And when a group of humans must spend a lot of time together, like in a group home, senior care facility, or daycare facility, it can be tough to control lice without professional intervention.

Should you discover someone you care about is in this situation, be proactive! Talk to management and volunteer to contact professional help on their behalf. And, for lack of a better phrase, make a stink about it. All of these parasites are manageable. Suppose you don't see a response from the facility and significant improvements within days. In that case, you can move your family member elsewhere and contact your local health board and other governing organizations.