Shingles (herpes zoster) is an infection that causes a painful rash. It is caused by the varicella-zoster virus (VZV). This is the same virus that causes chickenpox. After you have chickenpox, the virus stays in your body. It may not cause problems for many years. But as you get older, the virus may become active again and cause shingles.

Shingles is not contagious. You cannot get shingles from someone else. But you can catch chickenpox from someone with shingles if you have direct contact with fluid from their shingles rash.

The risk of spreading the virus is low if the shingles rash is kept covered. People with shingles cannot spread the virus before their rash blisters appear or after the rash crusts.

Anyone who has had chickenpox can get shingles. But the risk of shingles goes up as you get older. Shingles is most common in people over age 50.

People with weakened immune systems are at higher risk of getting shingles. This includes those who:

• Have immune system diseases such as HIV
• Have certain cancers
• Take medicines that weaken their immune system, such as steroids and medicines you take after an organ transplant

Your immune system may be weaker when you have an infection or are stressed. This can raise your risk of shingles.

It is rare, but possible, to get shingles more than once.

Early signs of shingles include burning or shooting pain and tingling or itching. It is usually on one side of the body or face. The pain can be mild to severe.

Up to several days later, you will get a rash. It consists of blisters that typically scab over in 7 to 10 days. The rash is usually a single stripe around either the left or the right side of the body. In other cases, the rash is only on one side of the face. In rare cases (usually among people with weakened immune systems), the rash may be more widespread. It might look similar to a chickenpox rash.

Some people may also have other symptoms:

• Fever
• Headache
• Chills
• Upset stomach

Shingles can cause other problems (complications):

• Postherpetic neuralgia (PHN) is the most common complication of shingles. It causes severe pain in the areas where you had the shingles rash. It usually gets better in a few weeks or months. But some people can have pain from PHN for many years, and it can interfere with daily life.
• Vision loss can happen if shingles affects your eye. It may be temporary or permanent.
• Hearing or balance problems are possible if you have shingles within or near your ear. You may also have weakness of the muscles on that side of your face. These problems can be temporary or permanent.

Very rarely, shingles can also lead to pneumonia, brain inflammation (encephalitis), or death.

Usually your health care provider can diagnose shingles by taking your medical history and looking at your rash. In some cases, your provider may scrape off tissue from the rash or swab some fluid from the blisters and send the sample to a lab for testing.

There is no cure for shingles. Antiviral medicines may help to make the attack shorter and less severe. They may also help prevent PHN. The medicines are most effective if you can take them within 3 days after the rash appears. So if you think you might have shingles, contact your provider as soon as possible.

Pain relievers may also help with the pain. A cool washcloth, calamine lotion, and oatmeal baths may help relieve some of the itching.

There is a vaccine, called Shingrix, to help prevent shingles and its complications. The Centers for Disease Control and Prevention recommends that healthy adults 50 years and older get the vaccine. Your provider might also recommend the vaccine if you are over 19 and have a weakened immune system. The vaccine is given in two doses.

If you have shingles, you can help prevent spreading the virus to others by:

• Staying away from:
  • People with weakened immune systems
  • People who have not had chickenpox or the chickenpox vaccine, especially if they are pregnant
  • Premature or low birth weight babies
• Keeping the rash covered
• Not touching or scratching the rash
• Washing your hands often

Centers for Disease Control and Prevention

Your small intestine is the longest part of your digestive system - about twenty feet long! It connects your stomach to your large intestine (or colon) and folds many times to fit inside your abdomen. Your small intestine does most of the digesting of the foods you eat. It has three areas called the duodenum, the ileum, and the jejunum.

Problems with the small intestine can include:

• Bleeding
• Celiac disease
• Crohn's disease
• Infections
• Intestinal cancer
• Intestinal obstruction
• Irritable bowel syndrome
• Ulcers, such as peptic ulcer

Treatment of disorders of the small intestine depends on the cause.

Staphylococcus (staph) is a group of bacteria. There are more than 30 types. A type called Staphylococcus aureus causes most infections.

Staph bacteria can cause many different types of infections, including:

• Skin infections, which are the most common types of staph infections.
• Bacteremia, an infection of the bloodstream. This can lead to sepsis, a very serious immune response to infection.
• Bone infections.
• Endocarditis, an infection of the inner lining of the heart chambers and valves.
• Food poisoning.
• Pneumonia.
• Toxic shock syndrome (TSS), a life-threatening condition caused by toxins from certain types of bacteria.

Some people carry staph bacteria on their skin or in their noses, but they do not get an infection. But if they get a cut or wound, the bacteria can enter the body and cause an infection.

Staph bacteria can spread from person to person. They can also spread on objects, such as towels, clothing, door handles, athletic equipment, and remotes. If you have staph and do not handle food properly when you are preparing it, you can also spread staph to others.

Anyone can develop a staph infection, but certain people are more likely to get one, including those who:

• Have a chronic condition such as diabetes, cancer, vascular disease, eczema, and lung disease
• Have a weakened immune system, such as from HIV, medicines to prevent organ rejection, or chemotherapy
• Had surgery
• Are in the hospital
• Use a catheter, breathing tube, or feeding tube
• Have an implanted device, such as a pacemaker or artificial joint or heart valve
• Have burns, especially if they are deep or cover a large area of the body
• Are on dialysis
• Inject illegal drugs
• Do contact sports, since you may have skin-to-skin contact with others or share equipment

The symptoms of a staph infection depend on the type of infection:

• Skin infections can look like pimples or boils. They may be red, swollen, and painful. Sometimes there is pus or other drainage. They can turn into impetigo, which turns into a crust on the skin, or cellulitis, a swollen, red area of skin that feels hot.
• Bone infections can cause pain, swelling, warmth, and redness in the infected area. You may also have chills and a fever.
• Endocarditis causes some flu-like symptoms: fever, chills, and fatigue. It also causes symptoms such as rapid heartbeat, shortness of breath, and fluid buildup in your arms or legs.
• Food poisoning typically causes nausea and vomiting, diarrhea, and fever. If you lose too many fluids, you may also become dehydrated.
• Pneumonia symptoms include a high fever, chills, and cough that doesn't get better. You may also have chest pain and shortness of breath.
• Toxic shock syndrome (TSS) causes high fever, sudden low blood pressure, vomiting, diarrhea, and confusion. You may have a sunburn-like rash somewhere on your body. TSS can lead to organ failure.

Your health care provider will do a physical exam and ask about your symptoms. Often, providers can tell if you have a staph skin infection by looking at it. To check for other types of staph infections, providers may do a culture, with a skin scraping, tissue sample, stool sample, or throat or nasal swabs. There may be other tests, such as imaging tests, depending on the type of infection.

Treatment for staph infections is antibiotics. Depending on the type of infection, the antibiotics might be a cream, ointment, medicines (to swallow), or intravenous (IV) medicine. If you have an infected wound, your provider might drain it. Sometimes you may need surgery for bone infections.

Some staph infections, such as MRSA (methicillin-resistant Staphylococcus aureus), are resistant to many antibiotics. There are still certain antibiotics that can treat these infections.

Certain steps can help to prevent staph infections:

• Use good hygiene, including washing your hands often.
• Don't share towels, sheets, or clothing with someone who has a staph infection.
• It's best not to share athletic equipment. If you do need to share, make sure that it is properly cleaned and dried before you use it.
• Practice food safety, including not preparing food for others when you have a staph infection.
• If you have a cut or wound, keep it covered.

Stem cells are cells with the potential to develop into many different types of cells in the body. They serve as a repair system for the body. There are two main types of stem cells: embryonic stem cells and adult stem cells.

Stem cells are different from other cells in the body in three ways:

• They can divide and renew themselves over a long time
• They are unspecialized, so they cannot do specific functions in the body
• They have the potential to become specialized cells, such as muscle cells, blood cells, and brain cells

Doctors and scientists are excited about stem cells because they could help in many different areas of health and medical research. Studying stem cells may help explain how serious conditions such as birth defects and cancer come about. Stem cells may one day be used to make cells and tissues for therapy of many diseases. Examples include Parkinson's disease, Alzheimer's disease, spinal cord injury, heart disease, diabetes, and arthritis.

NIH: National Institutes of Health

Stress is how your brain and body respond to a challenge or demand. When you are stressed, your body releases certain hormones. Hormones are chemicals that travel in your bloodstream and control how different parts of your body work. The hormones that are released when you are stressed make you alert and ready to act. They can raise your blood pressure, heart rate, and blood glucose (blood sugar) levels. This response is sometimes called a "fight or flight" response.

Everyone gets stressed from time to time. There are different types of stress. It can be short-term or long-term. It can be caused by something that happens once or something that keeps happening.

Not all stress is bad. In fact, it can help you survive in a dangerous situation. For example, one kind of stress is the jolt you may feel when a car pulls out in front of you while you are driving. This jolt of hormones helps you quickly hit the brakes to avoid an accident. A little short-term stress can sometimes be helpful. For example, the stress of having a deadline for school or your job may push you to get your work done on time. Once you finish it, that stress goes away.

But stress that lasts a long time can harm your health.

Long-term stress, or chronic stress, lasts for weeks, months, or longer. As you go about your life, your body is acting as if you're being threatened.

Causes of long-term stress include:

• Routine stress from the demands of work, school, family needs, money problems, and other daily pressures that don't stop.
• Stress from sudden, difficult changes in your life, such as divorce, illness, losing your job, or other unhappy life events that often have a long impact.
• Traumatic stress, which may happen when you're in danger of serious harm or death. Examples include being in a bad accident, a war, a flood, earthquake, or other frightening event. This type of stress can cause a long-lasting problem called post-traumatic stress disorder (PTSD).

People respond to stress in different ways. If you're stressed for a long time you may notice that you are:

• Getting sick more often than usual because stress weakens your body's ability to fight germs
• Having stomach problems or trouble digesting food
• Having trouble sleeping
• Having headaches
• Feeling sad, angry, or easily upset

When stress keeps going, your body acts as if you're always in danger. That's a lot of strain that may play a part in developing serious health problems, including:

• Depression
• Anxiety
• Heart disease
• High blood pressure
• Diabetes

It's possible to get used to the symptoms of stress and not even realize there's a problem. So when there's a lot of stress in your life, it's important to pay attention to how it affects you so you can do something about it.

Simple things that improve your mental health may be helpful in managing long-term stress, such as:

• Get regular exercise. A 30-minute daily walk can help you feel better and help keep your immune system strong, so you don't get sick.
• Try relaxing activities. You could look for an app or wellness program that uses breathing, meditation, or muscle relaxation exercises.
• Get enough sleep every night.
• Avoid too much caffeine.
• Decide what you need to do now and what can wait. And focus on what you got done each day, not on what you weren't able to do.
• Ask your family or friends for support.

Get help if you're having severe symptoms for 2 weeks or more, including:

• Trouble sleeping
• Changes in your eating that cause unwanted changes in your weight
• Troubles getting out of bed because of your mood
• Difficulty focusing your thoughts
• Losing interest in things you usually enjoy
• Not being able to do your usual daily activities

Always get help right away if stress is causing you to:

• Have thoughts of suicide
• Feel you can't cope
• Use drugs or alcohol more often than usual

Your health care provider may refer you to a mental health professional such as a psychologist or social worker.

NIH: National Institute of Mental Health