Treating your laundry, furniture, rugs and car

How does scabies spread?

scabiesmiteseggsfeces"Scabies is highly contagious, and person to person spread occurs via direct contact with the skin. Transfer from clothes and bedding occurs rarely and only if contaminated by infested people immediately beforehand."1

What does that mean to you? It means the greatest risk you face is reinfecting yourself by contacting clothes and sheets and towels you recently wore. Others will only catch it from you by extended skin contact or wearing or using cloth items you recently used.

Credit: the above photo is a microscopic picture of one scabies mite (lower left), eggs and feces (poop) under the skin.
Image from: www.nlm.nih.gov

Clothing, sheets and towels

Here is the key thing to know: dry, high heat kills the mites and their eggs. But make sure the laundry is completely dry, because you are literally drying out the mites and their eggs to kill them.

In a study, dry heat over 122 degrees F (50 degrees C) for over 10 minutes killed the mites and their eggs2. Dryers get to 150 degrees on high heat. The last 10 minutes of a drying cycle is usually a cool down period, so I don't count that as high heat. That's why I say "at least 30 minutes" on high heat. That will mean 20 minutes on high heat and 10 minutes of cool down. You can even remove laundry after the first 20 minutes.

You can test your dryer using a meat thermometer. Run some dry laundry on high heat and then put the temperature probe in to see if it gets over 122 degrees F (40 degrees C). One guy I corresponded with discovered his dryer wasn't getting hot enough. He probabaly could have just opened the back and cleaned out the lint to get it running better, but chose to buy a new dryer. Regardless, it's good to know if your dryer is killing the mites and eggs.

Don't wash your laundry first. If you do you will have to completely dry your laundry and then run it on high heat for another 30 minutes. It's best to put dry (dirty) laundry in the dryer first. After that you can wash it if you want to, but you don't have to.

Just throw blankets, bed pad, towels, quilts and pillows in the dryer before reusing them. It would be crazy to be washing and drying those large things every day! Don't work any harder than you have to. Save your time and energy for doing the treatment program.

In general, any mites or eggs on your clothing or sheets will die in 2 days. So if you simply leave clothes, towels and sheets in a drawer or on a shelf they will "self-decontaminate". There is no need to put things in bags. Mites can live longer than 2 days in low temperatures and high humidity, so to be on the safe side, leave unused clothing alone for 4 to 7 days. But if you do wear or use something, be sure to treat it in the dryer before you wear or use them again.

So it makes sense to select a few days' or a weeks' worth of clothes, sheets, etc to wear and use while doing the scabies treatment and put the rest aside until you are cured. No need to be laundering huge piles of stuff if you don't have to.

NOTE: how to treat furniture with permethrin spray, where to get it, and DIY recipes follow after this table.

5 Cures for Scabies

Sulfur lotion or cream

Pro: cheap, available in 2 days, has been used 2000 years

Con: mild skin irritation, mild sulfur odor

Cost: $15-25

Permethrin cream or lotion

Pro: cheap if you have insurance or mix it up yourself, USA doctors will actually prescribe it

Con: expensive with no insurance, mild skin irritation, you're not supposed to make your own (you have to decide)

Cost: $20 for DIY
$80 for prescription/dose

Benzyl Benzoate lotion

Pro: comes premixed, has been used for many years

Con: can sting when initially applied, has to be ordered from overseas and takes 10 days to arrive

Cost: $7/large bottle, but $35 for shipping

Eurax cream or lotion

Pro: very soothing, softens skin, kills itching, great for children or as an extra medicine

Con: not as powerful as other treatments, has to be ordered from overseas and takes 10 days to arrive

Cost: varies a lot

Around $15 from overseas, but around $400 in USA!

Ivermectin (oral - pill or paste)

Pro: almost no side effects, can use WITH the other treatments, has been used safely by millions of people

Con: pills hard to get in USA, horse paste is meant for mammals/animals only (you have to decide)

Cost: pills $30/dose,
horse paste $1/dose

 

Rugs and furniture

Rugs and furniture are not infective with normal scabies. They rarely carry any scabies mites or eggs. You don't have to treat rugs or curtains or counters.

Rugs and furniture are only infective in cases of crusted scabies. Look at the example photos below of crusted scabies. It is very rare and you probably don't have it. If you do have what look like crusted scabies, go to a hospital to be treated.

In normal case of scabies one usually has 5 to 20 live mites. I know it feels like more than that, but all that itching is due to the allergic reaction from the mite's by products, not from the actual, live mites. Your immune system actually kills of most of the new mites that hatch. Those surviving mites "want" to stay on you because they'll die if they are off you a couple days. Your body is like a boat in the ocean. The mites only leave to transfer to another ship (some other human body).

With crusted scabies the person has thousands of live mites. They literally ooze or drip mites all over and can the source of repeating scabies epidemics. Usually it is diabetics or others with severely impaired immune systems who develop crusted scabies.

crustedscabiesphotos

You don't need to treat furniture, rugs or your bed with insecticides, but you can vacuum cloth furniture and rugs if it makes you feel calmer. Also you can make a 1/2% solution of permethrin and water and spray cloth furniture and car seats if it makes you feel better. I did that because I was truly paranoid. See the next section for instructions.

Also I wanted to feel safer and be considerate of others, so I picked a chair to sit in when I watched TV or used my computer and put either a towel or a blanket over it. After I sat there, I tossed the blanket in the dryer for 30 minutes. Lots of people sat in my La-Z-Boy chair and no one ever caught scabies from me.

Car seats (and my cloth office chair)

Car seats are furniture in your car. They are unlikely to have any mites or eggs.

You can purchase a permethrin spray intended specifically for clothing. Click here to buy premixed Sawyer 1/2% permethrin spray at Amazon (or click on the Sawyer picture link to the right). You can also mix it up from concentrate (see recipe below).

It's simple to use. You just spray it on the cloth until it is visibly wet. After spraying, I let it air dry before using the car or chair. Do this in the garage or the shade because sunlight degrades permethrin. It didn't stain or discolor my car seats, but test it on an inconspicuous area if you want to be sure.

Remember, permethrin is very toxic to cats, fish and bees when it is wet. Once it is dry it is safe. But keep your cats away while you are spraying it around and until it dries.

I mixed up my own spray solution by purchasing permethrin concentrate and adding water to dilute it to .5% (one-half percent) to spray on cloth furniture. I used both 10% and 36.8% concentrates. The 36.8% permethrin contains petroleum distilates (something like mineral spirits), so you will need to let things air dry outside for around 16 hours to disipate the slight mineral spirits smell. I didn't notice any smell, but some folks are more sensitive. The 10% permethrin I bought contained no petroleum distillates so there is no mineral spirits" smell at all.

You can look on the label to see if it says "Contains petroleum distillates". To me, the "petroleum distillates" smells like mineral spirits, which can irritate skin. That's why you have to let it dry…to evaporate that out and not have it get on your skin or your pet's skin. Some folks are bothered by the smell, so open windows or do it outdoors. Petroleum distillates can really irritate one's skin, but once it has dried it's fine.

Obviously the no petroleum type is better for anything that might contact your skin.

Recipes for 1/2% permethrin spray

To make 1 gallon (or 4 liters) of .5% solution.

Using 36.8% permethrin concentrate
(Note: it may say "Permethrin SFR" on the bottle).

1 gallon water + 2 ounces 36.8% permethrin = 130 ounces of .51% concentration
COST $.85 per ounce x 2 = $1.70

Metric
4 liters water + 20 ml 36.8% permethrin = 4 liters of .5% permethrin

Using 10% permethrin concentrate

1 gallon water + 6.75 oz 10% Permethrin = 124.75 oz at .5% concentration
COST $.75 per ounce x 6.75 = $5.06

Metric
4 liters water + 200 ml 10% permethrin = 4.2 liters at .5% concentration

Obviously 36.8% permethrin is more economical, but it does contains petroleum products (something like mineral spirits) so you don't want to apply this stuff directly to your skin. It costs 3 times as much if you use 10% permethrin concentrate, but it contains no petroleum distillates. Before you order AND when you get the permethrin concentrate, look at the label…if it contains petroleum distillates it should say so on the label.

advancesinparasitologycover1Detailed information

"Transmission of scabies mites between hosts is largely via direct skin contact, while there is conflicting evidence regarding the role of fomites. [Note: "fomites" are objects and materials such as clothes, utensils or furniture]

Early human experimentation indicated that fomites were not likely to contribute significantly to transmission, with only two cases of scabies recorded in volunteers from 63 experiments involving exposure to the bedding or clothing of infected patients (Mellanby, 1941). However, it was noted that blankets were considered by some at the time as the chief means of transmission, particularly in the Army (Mellanby, 1941). Further human experimentation resulted in only four cases of scabies from 272 volunteers who got into warm beds recently vacated by infested patients (Mellanby, 1944).

Scabies mites have greatest survival away from a host in conditions of low temperature and high relative humidity, Mites have been shown to remain infective after up to 36 hours away from the host at 22- 24°C [72-75°F] and 40-80% relative humidity, with the time taken for subsequent penetration into the skin as a function of the time off the host (Arlian et al., 1984a, Arlian et al., 1989). Female tritonymphs [note: tritonymphs are mature adults that can lay eggs — this takes about 14 days after hatching] have been reported to survive as long as 19 days at 10°C [50°F] and 97% relative humidity (Arlian et al., 1989). This survival coupled with the recovery of live mites from the homes of scabies cases (Arlian et al., 1988) indicates that fomites may have a role in transmission.

It is likely that direct skin contact is the most important mode of transmission in cases of ordinary scabies, while fomites may also play a role in transmission from crusted scabies cases, in which extremely high numbers of mites are present (Section 5.2.2)."

from Advances in Parasitology, Volume 79, page 342, 2012

References

1 Walker GJA, Johnstone PW. Interventions for treating scabies. Cochrane Database Syst Rev 2000;(3): CD000320. (doi:.) doi: 10.1002/14651858.CD000320.

2. CDC Center for Disease Control — Scabies Frequently Asked Questions (FAQs)

SleepingCat250x250

This is pre-mixed 1/2% permethrin spray