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Hepatitis B FAQs

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I have cancer. My doctor wants to screen me for hepatitis B before starting immunosuppressive treatment. Why is this?

Treatments commonly used for cancer (e.g., chemotherapy, high-dose steroids) can activate hepatitis B in people who carry the virus. There have been many cases of people who were cured of their cancer who ended up with fatal liver damage as a result of an undiagnosed and untreated hepatitis B infection.

If you have cancer and are about to begin treatment, make sure that you have been vaccinated for hepatitis B and/or have been properly screened by your doctor.

I'm pregnant. Should I be screened for hepatitis B?

All expectant mothers should be screened for hepatitis B since it can be passed to your baby during delivery. If exposed to the virus, your baby's chance of developing a chronic infection is 90 percent.

If you are diagnosed with hepatitis B early in your pregnancy, you may be able to undergo hepatitis B treatment prior to birth. This can drastically reduce your baby's chance of getting the virus (in many cases to zero percent).

Can hepatitis B be spread through sex?

Yes – in the U.S., sexual contact with a person who carries the hepatitis B virus accounts for nearly two thirds of hepatitis B cases.

If I had hepatitis B before can I get it again?

If you successfully cleared a hepatitis B infection in the past, you will never get it again. Your body creates lifelong antibodies that protects you from the virus.

How does the hepatitis B vaccine work?

The hepatitis B vaccine is a series of shots given over six months. The vaccine contains small pieces of the virus, that when introduced slowly to the body, teaches the body to attack and destroy the virus. Unfortunately, the hepatitis B vaccine does not defend against other types of hepatitis (e.g., hepatitis C).

Can I get the hepatitis B virus from the vaccine?

No, you cannot. The vaccine is a copy of a very small part of the hepatitis B virus.

Is the hepatitis B vaccine safe?

The hepatitis B vaccine is considered safe; serious side effects are rare. Mild risks include a slight fever and soreness where the vaccine is given.

NOTE: The vaccine contains yeast and should not be given to people with severe yeast allergies. Speak with your doctor before getting vaccinated.

If I have hepatitis B, can I donate blood or organs?

If you ever tested positive for the hepatitis B virus, it's recommended that you do not donate any organs or bodily fluids, including semen.

I have symptoms. Does this mean I have a chronic infection?

Not necessarily. About 30 percent of adults who have an acute hepatitis B infection have symptoms.

How soon after I get hepatitis B can I expect to see symptoms?

Symptoms generally appear three months after exposure to the virus.

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