Because chronic viral hepatitis is often a "silent infection," it is difficult to know who is infected. Avoiding unsafe sex and exposure to blood are good preventive measures. Prior to availability of testing, transfusion of blood or blood products was a common mode of transmission of both hepatitis B and C. Today, with sensitive and specific testing of blood donors, the risk is dramatically reduced to nearly zero. Using condoms for intercourse or oral sex on a man also protects you against other sexually transmitted diseases. However, the best protection is receiving a vaccine. Safe and effective vaccines are available for HAV and HBV, including a new combination vaccine (Twinrix Hepatitis A Inactivated & Hepatitis B), but a vaccine for HCV is considered years away because the virus mutates, or changes, so easily. Sexual transmission of hepatitis C rarely occurs, but risk of this mode of transmission may be increased by sexual activity if during an episode of active genital herpes, cervicitis, or menstruation. Prevalence of hepatitis C is higher in men who have sex with men, and in persons with multiple sexual partners. Latex condoms have never been clinically tested, but may provide a barrier against transmission. Another, unproven but suspected mode of transmission for hepatitis is tattooing. About 10 percent of Americans, mainly men but an increasing number of women, are tattooed. Be certain that disposable equipment and sterile technique is used is you decide to get a tattoo.
Two kinds of protection are available for HAV. Both are injected.
Immune globulin is a preparation of antibodies given shortly before or immediately after possible exposure to HAV. You might opt for an immune globulin injection if you were taking a trip to a country where HAV is prevalent (Africa, Asia, Central and South America or Greenland), or if a member of your household were diagnosed with the infection. Immune globulin offers protection for two to three months if given within two weeks of exposure.
Two HAV vaccines are available (marketed under the names HAVRIX and VAQTA) for people two years of age and older. The vaccine is recommended for those at higher risk of the infection or those who are more likely to become seriously ill if they do get HAV (people with chronic liver disease or hemophilia). You will have to get two vaccinations, with the second one coming six to 12 months after the first.
Two doses of the vaccine produce protective antibodies in more than 94 percent of persons within one month, the CDC notes. The vaccine provides protection possibly for 20 years or more.
Hepatitis B, or HBV, is a highly contagious virus. Researchers estimate it is 100 times easier to get than HIV. The primary way people become infected is through contact with blood or body fluids of an infected person. For example, you can become infected by having sex or sharing needles with an infected person. In many developing countries the most common means of infection is mothers passing the virus to their infants during childbirth.
HBV is not spread through food, water or casual contact. Although the virus is found in saliva, kissing is not considered a high risk. The greatest risk of infection from sexual contact is vaginal and anal sex, and having multiple partners increases that risk. Oral sex also can transmit the virus but not as efficiently as vaginal or anal sex.
As with HCV, any procedure or activity that puts you in direct contact with another person's blood puts you at risk for HBV. Many people were infected through blood transfusions before HBV was screened in blood donors. Today, however, infection from transfusion is very rare. It is possible to get HBV from sharing razors, toothbrushes, pierced earrings and nail clippers but the risk is low. Injection drug users get HBV (and HCV) when sharing used syringes and needles because traces of a user's blood often remains inside the equipment. Tattooing and, possibly, body piercing, can spread the virus if needles are reused without sterilization.
Because of the prevalence of HBV, prevention through vaccination is recommended for all babies at birth and all children ages 11 to 18 years old who have not been vaccinated. Adults who put themselves at risk also should be vaccinated.
The HBV vaccine prevents both infection and the complications related to the infection. It is given in a series of three injections. After receiving all three injections, 90 percent of adults and 95 percent of children are protected against HBV infection, states the National Immunization Program. The injections cause only mild soreness in the arm. Side effects other than fever and headache are rare.
Some news reports have raised questions about the safety of HBV vaccines and suggested that the vaccine might be related to certain children's illnesses, such as multiple sclerosis and diabetes. Although government studies have found no increased incidence in these conditions in people who are immunized with the vaccine, U.S. Congressional hearings have been held to investigate the issue. Health officials from the U.S. Centers for Disease Control and Prevention (CDC), which sets guidelines on vaccines, recently testified to Congress that the HBV vaccine is one of the safest ever developed and there is no valid evidence linking it to any safety concerns, particularly diabetes, multiple sclerosis and sudden infant death syndrome.
Another product approved by the U.S. Food and Drug Administration for the prevention of Hepatitis B is hepatitis B immune globin (HBIG). The product is prepared from blood plasma that contains antibodies against surface antigen (anti-HBs) and is used for post-exposure prophylaxis in children and adults. It's also effective in preventing perinatal HBV infection among infants born to Hepatitis B-positive mothers.
No vaccine is available to prevent hepatitis C (HCV). To avoid the disease, you must control risk factors. Currently, the most common ways of getting HCV are injecting or snorting illegal drugs with shared equipment, tattooing or body piercing with unsterilized instruments, and using an infected person's toothbrush or razor. It has been difficult to prove that HCV can be transmitted sexually or what the risk of sexual transmission is. Epidemiologic studies suggest that approximately 5 percent of HCV cases in monogamous relationships, and 15 percent of HCV cases in people with multiple sex partners or history of sexually transmitted disease may be due to sexual transmission.
It is not spread by casual contact, such as hugging or kissing, nor by sharing eating utensils or coughing.
The risk of an HCV-infected mother to transmit the virus to her infant is approximately 6%. Risk increases in mothers who are HIV-positive. There is no evidence that breast-feeding spreads HCV.
Immunotherapy: Several drugs are currently being evaluated that boost the body's immune system to fight disease. Thymalfasin (Zadaxin), for example, is a synthetic version of a peptide (a small protein) originating from the thymus gland (which produces immune factors called T-cells). It is showing some promise for patients infected with hepatitis B and C and is in late-stage development for cancer and viral hepatitis worldwide.
Protease Inhibitors: Researchers are developing several different types of drugs (inhibitors) that block the hepatitis C enzymes (proteases, polymerase, helicase) used by the virus for reproduction. Several of these inhibitors are being evaluated in basic laboratory experiments. The first protease inhibitor used for only a few days in patients with genotype 1 infection proved effective in lowering HCV RNA. However, subsequent studies indicated that it was less effective against other genotypes, while animal studies found cardiovascular-related side effects. The drug, in its initial formulation, was removed from further investigation in clinical trials. Nonetheless, the prospects are exciting for development of new therapies over the next several years.
Vaccines: Vaccines against the hepatitis A and hepatitis B viruses are already available, however, another candidate, called Hepagene, is presently under investigation for treating, as well as preventing, hepatitis B. Researchers are attempting to develop vaccines to prevent hepatitis C infection, and a viable product is likely several years away.
Lesbians and Hepatitis
At the present time, there is no evidence to show women who have sex with other women have a higher incident of hepatitis A, B or C than women in general. However, this issue has not been adequately studied, and any woman who has risk factors for hepatitis or who is engaged in a sexual relationship with another woman with risk factors should consider vaccination.
"Prevention of Hepatitis A through active or passive immunization: recommendations of the Advisory Committee on Immunization Practices (ACIP)." Centers for Disease Control and Prevention. MMWR 1999; 48 (No. RR-12). pp. 1-38.
"Protect Your Baby With Hepatitis B Shots." Centers for Disease Control and Prevention. Updated June 2001. http://www.cdc.gov. Accessed Jan. 2002.
"Consumers Advised That Recent Hepatitis A Outbreaks Have Been Associated With Green Onions." FDA Talk Paper. Nov. 15, 2003. http://www.fda.gov. Accessed Nov. 2003.
GlaxoSmithKline. GlaxoSmithKline's TWINRIXr, first combination Hepatitis A & B vaccine, approved by FDA. May 14, 2001. http://www.gsk.com. Accessed Jan. 2002.
National Center for Infectious Diseases. Viral Hepatitis Resource Center. Reviewed Oct. 2003. http://www.cdc.gov. Accessed Nov. 2003.
"Hepatitis B" National Immunization Program, Centers for Disease Control and Prevention. Modified Feb. 2003. http://www.cdc.gov. Accessed Nov. 2003.
"Viral Hepatitis: A to E and Beyond." National Institute of Diabetes and Digestive and Kidney Disorders. May 2003. http://www.niddk.nih.gov. Accessed Nov. 2003.
"Hepatitis C" American Medical Association. Last updated May 2003. http://www.ama-assn.org. Accessed Nov. 2003.
Stephenson, Joan. "Vaccines Pose No Diabetes, Bowel Disease Risk." Journal of the American Medical Association. Nov. 8, 2000. Vol. 284, No. 18. pp. 2307-8.
Testimony of Harold S. Margolis, M.D., chief, Hepatitis Branch, Division of Viral and Rickettsial Diseases, National Center for Infectious Diseases, Centers for Disease Control and Prevention. Before the U.S. House of Representatives Committee on Government Reform, Subcommittee on Criminal Justice, Drug Policy and Human Resources. Modified March 2000. http://www.cdc.gov. Accessed Jan. 2002.
Hepatitis Foundation International. Copyright 2002. http://www.hepfi.org. Accessed Nov. 2003.
Veritas Medicine: Hepatitis C. http://www.veritasmedicine.com. Accessed Nov. 2003.
Keywords: hepatitis, hepatitis a, hepatitis b, hepatitis c, condoms, vaccine, vaccines, hbv vaccine, immune globulin, oral sex, anal sex, tattooing, body piercing, vaccination, children, multiple sclerosis, sexually transmitted disease, lesbians
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|Publication:||NWHRC Health Center - Hepatitis|
|Date:||Dec 16, 2005|
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