serologies

COVID-19 (coronavirus disease 2019) is a disease caused by a virus called SARS-CoV-2. There are two types of tests for this virus:

• A viral test tells you if you have a current infection. Viral tests can either be rapid tests or laboratory tests:
  • Rapid tests can be done in minutes. They are often antigen tests, which look for specific proteins from the virus. Some rapid tests are self-tests which you can do at home.
  • Laboratory tests can take days to complete and include PCR tests.
• An antibody (serology) test might tell you if you had a past infection.

If you need a COVID-19 test, you can:

• Buy a self-test online or at a store. Make sure that the test you buy has been authorized by the U.S. Food and Drug Administration (FDA).
• Check your state or local health department's website for information on testing in your area.
• Contact your health care provider.

Even if your COVID-19 viral test is negative (the test did not detect the virus), you should still take steps to protect yourself and others.

Centers for Disease Control and Prevention

Bacteria are living things that have only one cell. Under a microscope, they look like balls, rods, or spirals. They are so small that a line of 1,000 could fit across a pencil eraser. Most types of don't make you sick. Many types are helpful. Some of them help to digest food, destroy disease-causing cells, and give the body needed vitamins. Bacteria are also used in making healthy foods like yogurt and cheese.

But infectious bacteria can make you ill. They reproduce quickly in your body. Many give off chemicals called toxins, which can damage tissue and make you sick. Examples of bacteria that cause infections include Streptococcus, Staphylococcus, and E. coli.

Antibiotics are the usual treatment. When you take antibiotics, follow the directions carefully. Each time you take antibiotics, you increase the chances that bacteria in your body will learn to resist them causing antibiotic resistance. Later, you could get or spread an infection that those antibiotics cannot cure.

NIH: National Institute of Allergy and Infectious Diseases

Campylobacter infection is a common foodborne illness. You usually get it from eating contaminated food, especially raw or undercooked poultry. You can also get it from drinking contaminated water or raw milk, or handling infected animal feces (poop).

Some infected people don't have any symptoms. If you do have symptoms, they start two to five days after you are infected. They usually last about one week, and can include:

• Diarrhea (which could be bloody)
• Cramping
• Abdominal pain
• Fever
• Fatigue
• Nausea and vomiting

Health care providers use stool tests to make a diagnosis. Most people get better without treatment. You should drink extra fluids for as long as the diarrhea lasts. People who have a severe infection or a weakened immune system may need to take antibiotics. In rare cases, the infection can cause reactive arthritis or Guillain-Barre syndrome.

To prevent Campylobacter infection, cook poultry thoroughly. Use a separate cutting board and utensils for meats. Make sure to clean them carefully with soap and hot water after you use them.

Centers for Disease Control and Prevention

Chickenpox is an infection caused by the varicella-zoster virus. Most cases are in children under age 15, but older children and adults can get it. It spreads very easily from one person to another.

The classic symptom of chickenpox is an uncomfortable, itchy rash. The rash turns into fluid-filled blisters and eventually into scabs. It usually shows up on the face, chest, and back and then spreads to the rest of the body. Other symptoms include:

• Fever
• Headache
• Tiredness
• Loss of appetite

Chickenpox is usually mild and lasts 5 to 10 days. Calamine lotions and oatmeal baths can help with itching. Acetaminophen can treat the fever. Do not use aspirin for chickenpox; that combination can cause Reye syndrome.

Chickenpox can sometimes cause serious problems. Adults, babies, teenagers, pregnant women, and those with weak immune systems tend to get sicker from it. They may need to take antiviral medicines.

Once you catch chickenpox, the virus usually stays in your body. You probably will not get chickenpox again, but the virus can cause shingles in adults. A chickenpox vaccine can help prevent most cases of chickenpox, or make it less severe if you do get it.

Centers for Disease Control and Prevention

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

Infectious mononucleosis (mono) is a disease caused by viruses.The most common cause is the Epstein-Barr virus (EBV). Mono is contagious, which means it can spread from person to person. It is common among teenagers and young adults, especially college students.

Mono can be caused by many different viruses. But it is most often caused by the Epstein-Barr virus (EBV). EBV is found all over the world. Most people get an EBV infection at some point in their lives, but only some of them will get the symptoms of mono. EBV infections often happen during childhood or when someone is a young adult. EBV infections in children usually do not cause symptoms. And when they do, it's hard to tell the difference between the symptoms of mono and the symptoms of other common childhood illnesses such as the flu. Teens and young adults who get EBV are more likely to have symptoms that are typical of mono.

EBV and the other viruses that cause mono are usually spread through body fluids, especially saliva (spit). This means that you can get it through kissing. That's why mono is sometimes called "the kissing disease." But you can also get these viruses if you share food, drinks, forks, spoons, or lip balm with someone who has mono. Other less common ways of getting an infection are through blood transfusions, organ transplants, and blood and semen during sexual contact.

The symptoms of mono usually start four to six weeks after you get the infection. But they may start sooner in young children. The symptoms often develop slowly, and they may not all happen at the same time. They can include:

• Extreme fatigue
• Fever
• Sore throat
• Head and body aches
• Swollen lymph glands in your neck and armpits
• Rash
• Swollen liver, spleen, or both (these are less common symptoms)

Most people get better in two to four weeks. However, some people may feel fatigued for several more weeks. Occasionally, the symptoms can last for six months or longer.

Your healthcare provider may diagnose mono based on your symptoms and a physical exam. The exam will include checking to see if your lymph nodes, tonsils, liver, or spleen are swollen. In some cases, your provider might also order a mono test to confirm the diagnosis.

• Drinking plenty of fluids to avoid dehydration.
• Getting lots of rest.
• Taking over-the-counter medications for pain and fever. But don't give aspirin to children or teens because it may cause Reye syndrome. This syndrome is a rare, serious illness that can affect the brain and liver.

If you have severe symptoms, your provider may suggest additional treatment based on which organs in your body are affected by the mono.

Antibiotics don't treat viral infections, so they do not help with mono. Some people do get bacterial infections such as strep throat along with mono. In that case, you probably need antibiotics to treat the bacterial infection. But you should not take penicillin antibiotics like ampicillin or amoxicillin. Those antibiotics can cause a rash in people who have mono.

Mono can cause an enlarged spleen, which could rupture and cause a medical emergency. To try to protect the spleen, providers recommend avoiding intense exercise and contact sports until you fully recover (about a month).

There is no vaccine to protect against mono. To lower your chance of getting or spreading mono:

• Don't share food, drinks, forks, spoons, or lip balm with anyone, especially if you or the other person has mono.
• Don't kiss someone if you or the other person has mono.
• Wash your hands often with soap and water.

Centers for Disease Control and Prevention

Measles is an infectious disease caused by a virus. It spreads easily from person to person. It causes a blotchy red rash. The rash often starts on the head and moves down the body. Other symptoms include:

• Fever
• Cough
• Runny nose
• Conjunctivitis (pink eye)
• Feeling achy and run down
• Tiny white spots inside the mouth

Sometimes measles can lead to serious problems. There is no treatment for measles, but the measles-mumps-rubella (MMR) vaccine can prevent it.

"German measles", also known as rubella, is a completely different illness.

Centers for Disease Control and Prevention

Mumps is an illness caused by the mumps virus. It starts with:

• Fever
• Headache
• Muscle aches
• Tiredness
• Loss of appetite

After that, the salivary glands under the ears or jaw become swollen and tender. The swelling can be on one or both sides of the face. Symptoms last 7 to 10 days. Serious complications are rare.

You can catch mumps by being with another person who has it. There is no treatment for mumps, but the measles-mumps-rubella (MMR) vaccine can prevent it.

Before the routine vaccination program in the United States, mumps was a common illness in infants, children and young adults. Now it is a rare disease in the U.S.

Centers for Disease Control and Prevention

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 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 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 scrap 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