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Scabies causes intense itching. What you should know about what it looks and feels like - and how to treat scabies.
1. Scabies
Scabies causes an intense itch. Tiny mites, called Sarcoptes scabies var. hominis, crawl and burrow in skin. Some people see little red bumps, others may develop welts from an allergic-style reaction to these mites. Some just itch.
These mites are found worldwide. Some areas have high rates. It's thought 300 million people have scabies worldwide. In some communities, it is rare, less than 1%; in other communities, there are more infections, reaching over 10%, especially among children.
2. What is scabies like?
Scabies is all about itching. Some wake up in the middle night with scratch marks and cuts from where they scratched themselves in their sleep. Itching is most intense at night. It is most common in under arms, elbows, wrists, fingers and on breasts, buttocks, genitals. It usually does not affect the face.
Some have small pimply raised bumps. Some have welts. Some have scaly rashes. Some have no visible rash, just itching. Scratching can lead to skin infections with bacteria. Burrows can be identified, especially between fingers, as well as in skin folds in joints.
3. How did I get scabies?
Close - and usually prolonged - skin contact, especially in crowded conditions, can transmit scabies. A handshake can usually not spread infection. Instead infections usually occur in children playing in daycare, those in nursing homes, crowded living conditions, or prisons. Caregivers, such as in hospital settings, may be infected. Even a massage could spread the mites.
Households can be contaminated - bedding, towels and clothing - can transmit the mite to others. Usually this happens only when someone has a very severe infection.
Infections in adults are usually spread through sexual partners.
4. When does the itching start after I've been exposed?
Those who have had scabies before may develop itching within a day or two. Those who have not had scabies may not have symptoms for 4 to 6 weeks. They are still infectious during this time. These people just haven't developed an allergic response yet.
5. How do I treat scabies?
Scabies is treatable. Talk to your healthcare provider for scabies medications. Some medications are creams. They need to be spread all over, but read the directions, creams generally are not applied to the face or mucus membranes (i.e. in genital area). These creams are generally left on for a certain time and then washed off. Other infections are treated by pills. All good treatments kill the scabies mites; some kill the eggs as well.
It's important to wear clean clothes and use clean bedding. Avoid touching anyone else initially after treatment to avoid being reinfected. Be careful of medications that are intended for animals. Do not use veterinary medications on yourself or another person.
6. How is scabies diagnosed?
Scabies is often recognized on sight. Itching, rash, and burrow markings, especially between fingers, often are enough to diagnose the disease. The infection can also be diagnosed by seeing mites or mite eggs from a skin scraping sample under the microscope. Sometimes mites cannot be found, but the infection is still there.
7. It seems like scabies mites live forever, do they?
Nope. Scabies live on our skin for 1-2 months and multiply. But off our skin they don't live for more than a day or two. They will die if washed in hot water at 50 C (122 F) for 10 minutes. Others who don't have access to washing machines simply store items in trash bags tied and maybe placed out in the sun for a couple of days.
8. What is Norwegian or crusted scabies?
People who have weakened immune systems may have Norwegian scabies (crusted scabies) which is more severe. Standard scabies may involve 12-20 mites; crusted scabies may have over a thousands mites. This creates a crusted look, especially over patients' knuckles - even face, scalp. These patients very contagious including through household (or hospital) bedding, towels, furniture, clothing. This occurs largely in people who have HIV or leukemia or other immune disorders.
9. When will the itching stop?
Different medications and whether they come as a pill or a cream - work differently. Some may result briefly in more itching as the mites die. In general, if new rashes or burrows appear or itching continues 2-4 weeks after treatment, please see your doctor.
Many treatments work within 1 or 2 days. Talk to your doctor about how long the itching should last and whether there are treatments your doctor can provide to reduce the itching more quickly. Scabies can also be resistant to some treatments. The diagnosis may also be incorrect. You should talk to your healthcare provider if scabies treatments don't work. It might not be scabies,
10. Should I tell people I have scabies?
You should tell anyone who may be infected - and who might even reinfect you. You should tell sexual partners about the infection, who should be treated. Anyone in your household should be treated as well, especially if they have prolonged skin contact. Norwegian Scabies is very infectious.
11. Did I get scabies from my dog?
Human and pet scabies are different. Your dog (and very rarely your cat) can have a type of scabies mite infestation we usually call mange. These mites may jump on to you and itch for a bit, but they won't persist on you and will go away. It's a good idea to take your dog to the vet to be treated for your dog's sake and so you won't itch at all either.