Hepatitis B Vaccine Safe : Part 2

by Food and Drug Administration (FDA)

(Page 2 of 2)

Reaching Those at Risk

Most of the 2.5 million people in the United States who have received the vaccine are health-care workers. Because this group is the most easily reached of all those at high risk, health-care workers are the target of several programs to improve vaccination rates.

"Better awareness, that's the key," says Jim Paturas. He says SmithKline Beecham's program of free inoculations to emergency medical technicians and paramedics in several major cities has been a boon to the health community. "We've been able to use this as an educational vehicle to let EMTs and paramedics know they really are at high risk," he says.

In addition to the importance of vaccination, Paturas stresses that health-care workers must follow standard precautions for infectious disease every day, such as wearing gloves and other protective gear. "You need to consider how to best protect yourself," he says.

As to the cost of the vaccine as a possible deterrent to some, Paturas says, "What's $130? Well to some people that's a lot of money when they are either not being paid because they're volunteers or in some cases not being paid all that well."

A solution to the cost problem for health-care workers may come from an Occupational Safety and Health Administration proposal requiring employers to pay for the vaccine. Paturas says this proposal is a good start, but only a start. For example, because many emergency medical technicians are volunteers, it's not clear-cut who their employer is. Paturas adds that even among paid emergency workers, the employer may not be able to subsidize a vaccination program. Many emergency workers are employees of a local government, and cities like New York, for example, with close to 2,500 health-care employees, may not be able to shoulder the financial burden, he says. Paturas adds that more discussion needs to center around what kind of financial support the federal government will provide.

Mothers and Babies

The risk of a mother infected with hepatitis B passing the virus to her child when giving birth is greater than 70 percent. But quick action can prevent chronic infection with the virus between 85 and 95 percent of the time. First, the baby must receive an injection of immune globulin (antibodies made from human plasma) within 12 hours of birth. Second, at the same time, or as soon as possible thereafter, the baby needs to get the hepatitis B vaccine.

Because of the vaccine's effectiveness in exposed newborns, the Public Health Service's Immunization Practices Advisory Committee recently reemphasized the need for universal screening of all pregnant women for hepatitis B early in the pregnancy and treatment for all infants born to infected mothers.

For the first time, the committee also recommended vaccinating all infants from high-risk groups, especially

• Alaskan Natives
• Pacific Island groups
• immigrants and refugees from parts of the world where hepatitis B is very common, including China and Southeast Asia.

However, 30 percent of people who contract hepatitis B have no known risk factors. In addition, when someone is at risk not because of ethnic background but because of lifestyle, particularly IV drug abuse, it is almost too late to think about vaccination, according to CDC's Alter. "We have to start thinking about changing [the current] strategy to one perhaps where we have universal immunization of infants and adolescents so that protection from infection can be attained before high-risk behaviors begin," she says.

Without this change in strategy, the incidence of hepatitis B is likely to remain unchanged in the United States, Hoofnagle writes in his New England Journal of Medicine editorial. He adds that, "Members of the risk groups that are most likely to become infected are most unlikely to be identified early and reached by a vaccination program."

Other Hepatitis Types

While hepatitis B is the most serious form of hepatitis, there are several other forms of viral hepatitis.

Hepatitis A

Hepatitis A infections usually result from poor hygiene and poor sanitation. Because hepatitis A virus is excreted in feces, infected individuals can spread it by contaminating food or water. Anyone responsible for children in diapers is also at risk of getting and spreading the virus if hands aren't thoroughly washed after each diaper change.

The average incubation period of hepatitis A is 28 days. Symptoms include fever, nausea, lack of appetite, abdominal discomfort, dark urine, and jaundice. However, most infected children don't exhibit any symptoms at all, and those that do rarely have jaundice.

Hepatitis A infections can be prevented in individuals exposed to the virus by administering immune globulin — antibodies made from human plasma. A single dose of immune globulin given within two weeks of exposure will prevent 80 to 90 percent of infections, according to CDC. Treatment with immune globulin before exposure is recommended only for U.S. citizens traveling to developing countries.

In 1988, half the reported cases of hepatitis in this country were hepatitis A.

Non-A, Non-B Hepatitis Viruses

Hepatitis C is only one of possibly several viruses, some still unidentified, that formerly were grouped together under the name non-A, non-B hepatitis. Hepatitis C infects approximately 150,000 Americans every year, according to CDC. Blood transfusions, traditionally considered a major source of hepatitis C infection, only account for between 8 and 11 percent of all cases, according to CDC. Up to 40 percent of cases are associated with IV drug abuse, and between 4 and 8 percent are in health-care workers. However, in about 40 percent of the cases, the source of the infection is unknown. It is still unclear whether hepatitis C can be transmitted sexually.

Symptoms of hepatitis C are the same as for other forms of hepatitis. Like those infected with hepatitis B, people with hepatitis C infections can become chronic carriers and may develop cirrhosis and probably liver cancer, says Stephen Feinstone, M.D., chief of FDA's laboratory of hepatitis research. He adds that chronic infections seem to be even more common with hepatitis C than hepatitis B.

There is no treatment or vaccine for hepatitis C. A test that can be used to screen donated blood for an antibody to the hepatitis C virus has been developed, but it is still being evaluated by FDA.

Another form of non-A, non-B hepatitis (hepatitis E) has also been identified. It is transmitted enterically — from fecal contamination — like hepatitis A. It has occurred in epidemics or sporadically in parts of Asia, North and West Africa, and Mexico.

Delta Hepatitis

Delta hepatitis, also known as hepatitis D, is another virulent form of liver infection. The hepatitis D virus is defective and cannot exist by itself. Therefore, only people with active hepatitis B infections can contract hepatitis D. It is transmitted by the same routes as hepatitis B, and it most commonly affects IV drug abusers and people with hemophilia.

About the Author

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