Combination vaccine. There is also a combined hepatitis A and B vaccine (Twinrix) that is approved for those over age 18 years. This vaccine product contains trace amounts of thimerosal, neomycin, formalin, and yeast protein.3
TABLE
Recommended dosages and schedules of hepatitis A vaccines
| Vaccine | Age group | Dose | Volume | # Doses | Schedule |
|---|---|---|---|---|---|
| Havrix | 2–18 years | 720 ELU | 0.5 mL | 2 | 0, 6–12 mos |
| 19 years and older | 1440 ELU | 1.0 mL | 2 | 0, 6–12 mos | |
| Vaqta | 2–18 years | 25 U | 0.5 mL | 2 | 0, 6–18 mos |
| 19 years and older | 50 U | 1.0 mL | 2 | 0, 6–12 mos | |
| ELU, enzyme-linked immunosorbent assay (ELISA) units; U=units | |||||
FIGURE 3
Endemicity patterns of hepatitis A virus infection worldwide
This map generalizes currently available data, and patterns might vary within countries. Source: CDC.
Public health measures
Hepatitis A virus infection is reportable in every state. Prompt reporting by physicians is important, especially if the infected person is a food handler; serious, widespread, common-source outbreaks can be prevented by such actions. The role of the public health department is to verify cases, investigate outbreaks, institute outbreak control measures and make recommendations regarding routine vaccination. Some local public health departments may offer postexposure IG prophylaxis.
Use of immune globulin. Outbreak control measures will vary with the circumstances. Immune globulin for children and staff has proven effective in limiting outbreaks at daycare centers and should also be considered for parents of children at day care centers with a documented outbreak. A daycare center outbreak is defined as 1 or more cases in children or staff at a center or in 2 or more households of center attendees. Immune globulin is usually not effective in common source outbreaks, such as the recent Pennsylvania case, because the 2-week time period for protection has usually passed before the source of the outbreak is discovered.
Costs of Hepatitis A
While deaths from HAV are not common— approximately 100 per year—the individual and community morbidity caused by the virus can be considerable. Infection leads to hospitalization in 11% to 22% of cases and large economic losses with adults suffering 27 days of lost work and each case totaling over $2000 of direct and indirect costs.2 Local public health departments can also expend considerable resources trying to control outbreaks of this disease.
Indications for vaccination. The Centers for Disease Control and Prevention recommends routine vaccination for children who live in communities, counties, or states with HAV rates equal to or greater than 20/100,000, and it recommends considering routine vaccination when rates are equal to or greater than 10/100,000.
Following through. To lower community morbidity from HAV, be aware of the incidence and epidemiology of HAV in your community, suspect and accurately diagnose HAV illness using serological confirmation, promptly report all HAV cases to the local or state public health department, vaccinate patients who are in high-risk groups, offer prompt post-exposure prophylaxis to household and sexual contacts of those with acute HAV infection, and adhere to local recommendations regarding routine vaccination of children.
Correspondence
1825 E. Roosevelt, Phoenix, AZ 85006. E-mail: dougcampos@mail.maricopa.gov.