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Hepatitis is inflammation of the liver. Inflammation is swelling that happens when tissues of the body are injured or infected. It can damage your liver. This swelling and damage can affect how well your liver functions.

Hepatitis A is a type of viral hepatitis. It causes an acute, or short-term, infection. This means that people usually get better without treatment after a few weeks.

Thanks to a vaccine, hepatitis A is not very common in the United States.

Hepatitis A is caused by the hepatitis A virus. The virus spreads through contact with an infected person's stool. This can happen if you:

• Eat food made by someone who has the virus and did not properly wash their hands after using the bathroom
• Drink contaminated water or eat foods that were rinsed with contaminated water
• Have close personal contact with someone who has hepatitis A. This could be through certain types of sex (like oral-anal sex), taking care of someone who is ill, or using illegal drugs with others.

Although anyone can get hepatitis A, you are at higher risk if you:

• Travel to developing countries
• Have sex with someone who has hepatitis A
• Are a man who has sex with men
• Use illegal drugs
• Are experiencing homelessness
• Live with or care for someone who has hepatitis A
• Live with or care for a child recently adopted from a country where hepatitis A is common

Not everyone with hepatitis A has symptoms. Adults are more likely to have symptoms than children. If you do have symptoms, they usually start 2 to 7 weeks after infection. They can include:

• Dark yellow urine
• Diarrhea
• Fatigue
• Fever
• Gray- or clay-colored stools
• Joint pain
• Loss of appetite
• Nausea and/or vomiting
• Abdominal pain
• Yellowish eyes and skin, called jaundice

The symptoms usually last less than 2 months, although some people can be ill for as long as 6 months.

You are at a higher risk of getting a more severe infection from hepatitis A if you also have HIV, hepatitis B, or hepatitis C.

In rare cases, hepatitis A may lead to liver failure. This is more common in adults over age 50 and in people who have another liver.

To diagnose hepatitis A, your health care provider may use many tools:

• A medical history, which includes asking about your symptoms
• A physical exam
• Blood tests, including tests for viral hepatitis

There is no specific treatment for hepatitis A. The best way to recover is to rest, drink plenty of liquids, and eat healthy foods. Your provider may also suggest medicines to help relieve symptoms. In more severe cases, you may need care in a hospital.

The best way to prevent hepatitis A is to get the hepatitis A vaccine. It is also important to have good hygiene, especially washing your hands thoroughly after you go to the bathroom.

National Institute of Diabetes and Digestive and Kidney Diseases

Hepatitis is inflammation of the liver. Inflammation is swelling that happens when tissues of the body are injured or infected. It can damage your liver. This swelling and damage can affect how well your liver functions.

Hepatitis can be an acute (short-term) infection or a chronic (long-term) infection. Some types of hepatitis cause only acute infections. Other types can cause both acute and chronic infections.

There are different types of hepatitis, with different causes:

• Viral hepatitis is the most common type. It is caused by one of several viruses -- hepatitis viruses A, B, C, D, and E. In the United States, A, B, and C are the most common.
• Alcoholic hepatitis is caused by heavy alcohol use
• Toxic hepatitis can be caused by certain poisons, chemicals, medicines, or supplements
• Autoimmune hepatitis is a chronic type in which your body's immune system attacks your liver. The cause is not known, but genetics and your environment may play a role.

Hepatitis A and hepatitis E usually spread through contact with food or water that was contaminated with an infected person's stool. You can also get hepatitis E by eating undercooked pork, deer, or shellfish.

Hepatitis B, hepatitis C, and hepatitis D spread through contact with the blood of someone who has the disease. Hepatitis B and D may also spread through contact with other body fluids. This can happen in many ways, such as sharing drug needles or having unprotected sex.

The risks are different for the different types of hepatitis. For example, with most of the viral types, your risk is higher if you have unprotected sex. People who drink a lot over long periods of time are at risk for alcoholic hepatitis.

Some people with hepatitis do not have symptoms and do not know they are infected. If you do have symptoms, they may include:

• Fever
• Fatigue
• Loss of appetite
• Nausea and/or vomiting
• Abdominal pain
• Dark urine
• Clay-colored bowel movements
• Joint pain
• Jaundice, yellowing of your skin and eyes

If you have an acute infection, your symptoms can start anywhere between 2 weeks to 6 months after you got infected. If you have a chronic infection, you may not have symptoms until many years later.

Chronic hepatitis can lead to complications such as cirrhosis (scarring of the liver), liver failure, and liver cancer. Early diagnosis and treatment of chronic hepatitis may prevent these complications.

To diagnose hepatitis, your health care provider:

• Will ask about your symptoms and medical history
• Will do a physical exam
• Will likely do blood tests, including tests for viral hepatitis
• Might do imaging tests, such as an ultrasound, CT scan, or MRI
• May need to do a liver biopsy to get a clear diagnosis and check for liver damage

Treatment for hepatitis depends on which type you have and whether it is acute or chronic. Acute viral hepatitis often goes away on its own. To feel better, you may just need to rest and get enough fluids. But in some cases, it may be more serious. You might even need treatment in a hospital.

There are different medicines to treat the different chronic types of hepatitis. Possible other treatments may include surgery and other medical procedures. People who have alcoholic hepatitis need to stop drinking. If your chronic hepatitis leads to liver failure or liver cancer, you may need a liver transplant.

There are different ways to prevent or lower your risk for hepatitis, depending on the type of hepatitis. For example, not drinking too much alcohol can prevent alcoholic hepatitis. There are vaccines to prevent hepatitis A and B. Autoimmune hepatitis cannot be prevented.

NIH: National Institute of Diabetes and Digestive and Kidney Diseases

Your liver is the largest organ inside your body. It helps your body digest food, store energy, and remove poisons. Fatty liver disease is a condition in which fat builds up in your liver. There are two main types:

• Nonalcoholic fatty liver disease (NAFLD)
• Alcoholic fatty liver disease, also called alcoholic steatohepatitis

NAFLD is a type of fatty liver disease that is not related to heavy alcohol use. There are two kinds:

• Simple fatty liver, in which you have fat in your liver but little or no inflammation or liver cell damage. Simple fatty liver typically does not get bad enough to cause liver damage or complications.
• Nonalcoholic steatohepatitis (NASH), in which you have inflammation and liver cell damage, as well as fat in your liver. Inflammation and liver cell damage can cause fibrosis, or scarring, of the liver. NASH may lead to cirrhosis or liver cancer.

Alcoholic fatty liver disease is due to heavy alcohol use. Your liver breaks down most of the alcohol you drink, so it can be removed from your body. But the process of breaking it down can generate harmful substances. These substances can damage liver cells, promote inflammation, and weaken your body's natural defenses. The more alcohol that you drink, the more you damage your liver. Alcoholic fatty liver disease is the earliest stage of alcohol-related liver disease. The next stages are alcoholic hepatitis and cirrhosis.

The cause of nonalcoholic fatty liver disease (NAFLD) is unknown. Researchers do know that it is more common in people who:

• Have type 2 diabetes and prediabetes
• Have obesity
• Are middle aged or older (although children can also get it)
• Are Hispanic, followed by non-Hispanic whites. It is less common in African Americans.
• Have high levels of fats in the blood, such as cholesterol and triglycerides
• Have high blood pressure
• Take certain drugs, such as corticosteroids and some cancer drugs
• Have certain metabolic disorders, including metabolic syndrome
• Have rapid weight loss
• Have certain infections, such as hepatitis C
• Have been exposed to some toxins

NAFLD affects about 25% of people in the world. As the rates of obesity, type 2 diabetes, and high cholesterol are rising in the United States, so is the rate of NAFLD. NAFLD is the most common chronic liver disorder in the United States.

Alcoholic fatty liver disease only happens in people who are heavy drinkers, especially those who have been drinking for a long period of time. The risk is higher for heavy drinkers who are women, have obesity, or have certain genetic mutations.

Both NAFLD and alcoholic fatty liver disease are usually silent diseases with few or no symptoms. If you do have symptoms, you may feel tired or have discomfort in the upper right side of your abdomen.

Because there are often no symptoms, it is not easy to find fatty liver disease. Your doctor may suspect that you have it if you get abnormal results on liver tests that you had for other reasons. To make a diagnosis, your doctor will use:

• Your medical history
• A physical exam
• Various tests, including blood and imaging tests, and sometimes a biopsy

As part of the medical history, your doctor will ask about your alcohol use, to find out whether fat in your liver is a sign of alcoholic fatty liver disease or nonalcoholic fatty liver (NAFLD). He or she will also ask which medicines you take, to try to determine whether a medicine is causing your NAFLD.

During the physical exam, your doctor will examine your body and check your weight and height. Your doctor will look for signs of fatty liver disease, such as:

• An enlarged liver
• Signs of cirrhosis, such as jaundice, a condition that causes your skin and whites of your eyes to turn yellow

You will likely have blood tests, including liver function tests and blood count tests. In some cases you may also have imaging tests, like those that check for fat in the liver and the stiffness of your liver. Liver stiffness can mean fibrosis, which is scarring of the liver. In some cases you may also need a liver biopsy to confirm the diagnosis, and to check how bad the liver damage is.

Doctors recommend weight loss for nonalcoholic fatty liver. Weight loss can reduce fat in the liver, inflammation, and fibrosis. If your doctor thinks that a certain medicine is the cause of your NAFLD, you should stop taking that medicine. But check with your doctor before stopping the medicine. You may need to get off the medicine gradually, and you might need to switch to another medicine instead.

There are no medicines that have been approved to treat NAFLD. Studies are investigating whether a certain diabetes medicine or Vitamin E can help, but more studies are needed.

The most important part of treating alcohol-related fatty liver disease is to stop drinking alcohol. If you need help doing that, you may want to see a therapist or participate in an alcohol recovery program. There are also medicines that can help, either by reducing your cravings or making you feel sick if you drink alcohol.

Both alcoholic fatty liver disease and one type of nonalcoholic fatty liver disease (nonalcoholic steatohepatitis) can lead to cirrhosis. Doctors can treat the health problems caused by cirrhosis with medicines, operations, and other medical procedures. If the cirrhosis leads to liver failure, you may need a liver transplant.

If you have any of the types of fatty liver disease, there are some lifestyle changes that can help:

• Eat a healthy diet, limiting salt and sugar, plus eating lots of fruits, vegetables, and whole grains
• Get vaccinations for hepatitis A and B, the flu and pneumococcal disease. If you get hepatitis A or B along with fatty liver, it is more likely to lead to liver failure. People with chronic liver disease are more likely to get infections, so the other two vaccinations are also important.
• Get regular exercise, which can help you lose weight and reduce fat in the liver
• Talk with your doctor before using dietary supplements, such as vitamins, or any complementary or alternative medicines or medical practices. Some herbal remedies can damage your liver.

Hepatitis is inflammation of the liver. Inflammation is swelling that happens when tissues of the body are injured or infected. It can damage your liver. This swelling and damage can affect how well your liver functions.

Hepatitis B is a type of viral hepatitis. It can cause an acute (short-term) or chronic (long-term) infection. People with an acute infection usually get better on their own without treatment. Some people with chronic hepatitis B will need treatment.

Thanks to a vaccine, hepatitis B is not very common in the United States. It is more common in certain parts of the world, such as sub-Saharan Africa and parts of Asia.

Hepatitis B is caused by the hepatitis B virus. The virus spreads through contact with blood, semen, or other body fluids from a person who has the virus.

Anyone can get hepatitis B, but the risk is higher in:

• Infants born to mothers who have hepatitis B
• People who inject drugs or share needles, syringes, and other types of drug equipment
• Sex partners of people with hepatitis B, especially if they are not using latex or polyurethane condoms during sex
• Men who have sex with men
• People who live with someone who has hepatitis B, especially if they use the same razor, toothbrush, or nail clippers
• Health care and public-safety workers who are exposed to blood on the job
• Hemodialysis patients
• People who have lived in or traveled often to parts of the world where hepatitis B is common
• Have diabetes, hepatitis C, or HIV

Often, people with hepatitis B don't have symptoms. Adults and children over 5 are more likely to have symptoms than younger children.

Some people with acute hepatitis B have symptoms 2 to 5 months after infection. These symptoms can include:

• Dark yellow urine
• Diarrhea
• Fatigue
• Fever
• Gray- or clay-colored stools
• Joint pain
• Loss of appetite
• Nausea and/or vomiting
• Abdominal pain
• Yellowish eyes and skin, called jaundice

If you have chronic hepatitis B, you may not have symptoms until complications develop. This could be decades after you were infected. For this reason, hepatitis B screening is important, even if you have no symptoms. Screening means that you are tested for a disease even though you don't have symptoms. If you are at high risk, your health care provider may suggest screening.

In rare cases, acute hepatitis B can cause liver failure.

Chronic hepatitis B can develop into a serious disease that causes long-term health problems such as cirrhosis (scarring of the liver), liver cancer, and liver failure.

If you have ever had hepatitis B, the virus may become active again, or reactivated, later in life. This could start to damage the liver and cause symptoms.

To diagnose hepatitis B, your health care provider may use many tools to make a diagnosis:

• A medical history, which includes asking about your symptoms
• A physical exam
• Blood tests, including tests for viral hepatitis

If you have acute hepatitis B, you probably don't need treatment. Some people with chronic hepatitis B don't need treatment. But if you have a chronic infection and blood tests show that hepatitis B could be damaging your liver, you may need to take antiviral medicines.

The best way to prevent hepatitis B is to get the hepatitis B vaccine.

You can also reduce your chance of hepatitis B infection by:

• Not sharing drug needles or other drug materials
• Wearing gloves if you have to touch another person's blood or open sores
• Making sure your tattoo artist or body piercer uses sterile tools
• Not sharing personal items, such as toothbrushes, razors, or nail clippers
• Using a latex condom during sex. If your or your partner is allergic to latex, you can use polyurethane condoms.

If you think you have been in contact with the hepatitis B virus, see your health care provider right away. Your provider may give you a dose of the hepatitis B vaccine to prevent infection. In some cases, your provider may also give you a medicine called hepatitis B immune globulin (HBIG). You need to get the vaccine and the HBIG (if needed) as soon as possible after coming into contact with the virus. It is best if you can get them within 24 hours.

National Institute of Diabetes and Digestive and Kidney Diseases

Your liver is the largest organ inside your body. It helps your body digest food, store energy, and remove poisons.

There are many kinds of liver diseases:

• Diseases caused by viruses, such as hepatitis A, hepatitis B, and hepatitis C
• Diseases caused by drugs, poisons, or too much alcohol. Examples include fatty liver disease and cirrhosis.
• Liver cancer
• Inherited diseases, such as hemochromatosis and Wilson disease

Symptoms of liver disease can vary, but they often include swelling of the abdomen and legs, bruising easily, changes in the color of your stool and urine, and jaundice, or yellowing of the skin and eyes. Sometimes there are no symptoms. Tests such as imaging tests and liver function tests can check for liver damage and help to diagnose liver diseases.

Aplastic anemia is a rare but serious blood disorder. If you have it, your bone marrow doesn't make enough new blood cells. It happens when there is damage to stem cells inside your bone marrow. There are different types of aplastic anemia, including Fanconi anemia.

The causes of aplastic anemia can include:

• Autoimmune disorders, which are the most common cause
• Certain inherited gene changes, such as the one that can cause Fanconi anemia
• Toxic substances, such as pesticides, arsenic, and benzene
• Radiation therapy and chemotherapy for cancer
• Certain medicines
• Viral infections such as hepatitis, Epstein-Barr virus, or HIV
• Pregnancy

In many people, the cause is unknown. This is called idiopathic aplastic anemia.

Aplastic anemia can develop suddenly or slowly. It can be mild or severe. The symptoms of aplastic anemia can include:

• Fatigue
• Weakness
• Dizziness
• Shortness of breath
• Easy bruising or bleeding

Aplastic anemia can cause other problems, including frequent infections and bleeding. It raises your risk of developing a serious blood disorder.

If not treated, aplastic anemia can also lead to heart problems such as an arrhythmia (a problem with the rate or rhythm of your heartbeat), an enlarged heart, or heart failure.

To find out if you have aplastic anemia, your doctor will:

• Take your medical and your family medical histories
• Do a physical exam
• Order tests, such as tests to check if you have low numbers of cells in your bone marrow and blood

If you have aplastic anemia, your doctor will create a treatment plan for you. The plan will be based on how severe the anemia is and what is causing it. Treatments can include:

• Blood transfusions
• Blood and marrow stem cell transplants
• Medicines to suppress your immune system

Because of the risk of blood disorders, your doctor will monitor your condition and screen you for blood disorders regularly.

NIH: National Heart, Lung, and Blood Institute

Vaccines are injections (shots), liquids, pills, or nasal sprays that you take to teach the immune system to recognize and defend against harmful germs. The germs could be viruses or bacteria.

Some types of vaccines contain germs that cause disease. But the germs have been killed or weakened enough that they won't make your child sick. Some vaccines only contain a part of a germ. Other types of vaccines include instructions for your cells to make a protein of the germ.

These different vaccine types all spark an immune response, which helps the body fight off the germs. Your child's immune system will also remember the germ and attack it if that germ ever invades again. This protection against a certain disease is called immunity.

Babies are born with immune systems that can fight most germs, but there are some serious diseases they can't handle. That's why they need vaccines to strengthen their immune system.

These diseases once killed or harmed many infants, children, and adults. But now with vaccines, your child can get immunity from these diseases without having to get sick. And for a few vaccines, getting vaccinated can actually give you a better immune response than getting the disease would.

Vaccinating your child also protects others. Normally, germs can travel quickly through a community and make a lot of people sick. If enough people get sick, it can lead to an outbreak. But when enough people are vaccinated against a certain disease, it's harder for that disease to spread to others. The entire community is less likely to get the disease. This is called "community immunity."

Community immunity is especially important for the people who can't get certain vaccines. For example, they may not be able to get a vaccine because they have weakened immune systems. Others may be allergic to certain vaccine ingredients. And newborn babies are too young to get some vaccines. Community immunity can help to protect them all.

Vaccines are safe. They must go through extensive safety testing and evaluation before they are approved in the United States.

Some people worry that childhood vaccines could cause autism spectrum disorder (ASD). But many scientific studies have looked at this and have found no link between vaccines and autism.

No, vaccines do not overload the immune system. Every day, a healthy child's immune system successfully fights off thousands of germs. When your child gets vaccines, they are getting weakened or dead germs. So even if they get several vaccines in one day, they are being exposed to a tiny amount of germs compared to what they encounter every day in their environment.

Your child will get vaccines during well-child visits. They will be given according to the vaccine schedule. This schedule lists which vaccines are recommended for children. It includes who should get the vaccines, how many doses they need, and at what age they should get them. In the United States, the Centers for Disease Control and Prevention (CDC) publishes the vaccine schedule.

Following the vaccine schedule allows your child to get protection from the diseases at exactly the right time. It gives their body the chance to build up immunity before being exposed to these very serious diseases.

Cirrhosis is scarring of the liver. Scar tissue forms because of injury or long-term disease. Scar tissue cannot do what healthy liver tissue does - make protein, help fight infections, clean the blood, help digest food and store energy. Cirrhosis can lead to :

• Easy bruising or bleeding, or nosebleeds
• Swelling of the abdomen or legs
• Extra sensitivity to medicines
• High blood pressure in the vein entering the liver
• Enlarged veins called varices in the esophagus and stomach. Varices can bleed suddenly.
• Kidney failure
• Jaundice
• Severe itching
• Gallstones

A small number of people with cirrhosis get liver cancer.

Your doctor will diagnose cirrhosis with blood tests, imaging tests, or a biopsy.

Cirrhosis has many causes. In the United States, the most common causes are chronic alcoholism and hepatitis. Nothing will make the scar tissue disappear, but treating the cause can keep it from getting worse. If too much scar tissue forms, you may need to consider a liver transplant.

NIH: National Institute of Diabetes and Digestive and Kidney Diseases

Each year, around 48 million people in the United States get sick from contaminated food. Common causes include bacteria and viruses. Less often, the cause may be a parasite or a harmful chemical, such as a high amount of pesticides. Symptoms of foodborne illness depend on the cause. They can be mild or serious. They usually include:

• Upset stomach
• Abdominal cramps
• Nausea and vomiting
• Diarrhea
• Fever
• Dehydration

Most foodborne illnesses are acute. This means that they happen suddenly and last a short time.

It takes several steps to get food from the farm or fishery to your dining table. Contamination can happen during any of these steps. For example, it can happen to:

• Raw meat during slaughter
• Fruits and vegetables when they are growing or when they are processed
• Refrigerated foods when they are left on a loading dock in warm weather

But it can also happen in your kitchen if you leave food out for more than 2 hours at room temperature. Handling food safely can help prevent foodborne illnesses.

Most people with foodborne illness get better on their own. It is important to replace lost fluids and electrolytes to prevent dehydration. If your health care provider can diagnose the specific cause, you may get medicines such as antibiotics to treat it. For more serious illness, you may need treatment at a hospital.

NIH: National Institute of Diabetes and Digestive and Kidney Diseases

Hepatitis is inflammation of the liver. Inflammation is swelling that happens when tissues of the body are injured or infected. Inflammation can damage organs.

There are different types of hepatitis. One type, hepatitis C, is caused by the hepatitis C virus (HCV). Hepatitis C can range from a mild illness lasting a few weeks to a serious, lifelong illness.

Hepatitis C can be acute or chronic:

• Acute hepatitis C is a short-term infection. The symptoms can last up to 6 months. Sometimes your body is able to fight off the infection and the virus goes away. But for most people, an acute infection leads to chronic infection.
• Chronic hepatitis C is a long-lasting infection. If it is not treated, it can last for a lifetime and cause serious health problems, including liver damage, cirrhosis (scarring of the liver), liver cancer, and even death.

Hepatitis C spreads through contact with the blood of someone who has HCV. This contact may be through:

• Sharing drug needles or other drug materials with someone who has HCV. In the United States, this is the most common way that people get hepatitis C.
• Getting an accidental stick with a needle that was used on someone who has HCV. This can happen in health care settings.
• Being tattooed or pierced with tools or inks that were not sterilized after being used on someone who has HCV
• Having contact with the blood or open sores of someone who has HCV
• Sharing personal care items that may have come in contact with another person's blood, such as razors or toothbrushes
• Being born to a mother with HCV
• Having unprotected sex with someone who has HCV

Before 1992, hepatitis C was also commonly spread through blood transfusions and organ transplants. Since then, there has been routine testing of the U.S. blood supply for HCV. It is now very rare for someone to get HCV this way.

You are more likely to get hepatitis C if you:

• Have injected drugs
• Had a blood transfusion or organ transplant before July 1992
• Have hemophilia and received clotting factor before 1987
• Have been on kidney dialysis
• Have been in contact with blood or infected needles at work
• Have had tattoos or body piercings
• Have worked or lived in a prison
• Were born to a mother with hepatitis C
• Have HIV
• Have had more than one sex partner in the last 6 months
• Have had a sexually transmitted disease
• Are a man who has had sex with men (MSM)

If you are at high risk for hepatitis C, your health care provider will likely recommend that you get tested for it.

Most people with hepatitis C have no symptoms. Some people with acute hepatitis C do have symptoms within 1 to 3 months after they are exposed to the virus. These symptoms may include:

• Dark yellow urine
• Fatigue
• Fever
• Gray- or clay-colored stools
• Joint pain
• Loss of appetite
• Nausea and/or vomiting
• Pain in your abdomen (belly)
• Jaundice (yellowish eyes and skin)

If you have chronic hepatitis C, you probably will not have symptoms until it causes complications. This can happen decades after you were infected. For this reason, hepatitis C screening is important, even if you have no symptoms.

Without treatment, hepatitis C may lead to cirrhosis, liver failure, and liver cancer. Early diagnosis and treatment of hepatitis C can prevent these complications.

Providers diagnose hepatitis C based on your medical history, a physical exam, and blood tests.

If you do have hepatitis C, you may need additional tests to check for liver damage. These tests may include other blood tests, an ultrasound of the liver, and a liver biopsy.

Treatment for hepatitis C is with antiviral medicines. They can cure the disease in most cases.

If you have acute hepatitis C, your provider may wait to see if your infection becomes chronic before starting treatment.

If your hepatitis C causes cirrhosis, you should see a doctor who specializes in liver diseases. Treatments for health problems related to cirrhosis include medicines, surgery, and other medical procedures. If your hepatitis C leads to liver failure or liver cancer, you may need a liver transplant.

There is no vaccine for hepatitis C. But you can help protect yourself from hepatitis C infection by:

• Not sharing drug needles or other drug materials.
• Wearing gloves if you have to touch another person's blood or open sores.
• Making sure your tattoo artist or body piercer uses sterile tools and unopened ink.
• Not sharing personal items such toothbrushes, razors, or nail clippers.
• Using a latex condom during sex. If your or your partner is allergic to latex, you can use polyurethane condoms.

NIH: National Institute of Diabetes and Digestive and Kidney Diseases