3 Facts You Should Know About Hepatitis A Virus

Hepatitis A infection rates have decreased in the United States and are the lowest they have been in 40 years.

Hepatitis A infection rates have decreased in the United States and are the lowest they have been in 40 years. Reasons include introduction of the vaccine in 1995, with an emphasis placed on immunizing all children, travelers to certain countries, and those at risk for contracting the disease. In fact, hepatitis A rates have declined by 95% since the vaccine became available.1 Check out these 3 facts about hepatitis A virus (HAV).

  • HAV is transmitted through the fecal-oral route

Most infections result from personal contact with an infected household member or sex partner. Also, some cases of HAV can occur from exposure to fecally contaminated food or water. HAV virus can be prevented through good hygiene. Educate patients to wash their hands with soap and water after using the bathroom, changing diapers, and before preparing or eating food. Keep in mind that the virus can be killed by heating to > 185 degrees F for one minute.1However, HAV can still spread from cooked food that is contaminated after cooking.

  • Hepatitis A vaccination is recommended for certain patient populations1

The hepatitis A vaccine is recommended for the following groups:

  • All children at 1 year of age
  • Children and teens 2-18 years of age living in states or communities with high HAV rates
  • Individuals traveling to countries with high or intermediate HAV rates
  • Men who have sex with men
  • Users of illegal injection and noninjection drugs
  • Individuals with occupational risk of infection (working with HAV-infected primates or HAV research lab)
  • People with chronic liver disease
  • Individuals with clotting-factor disorders that are administered clotting-factor concentrates
  • Household members and other caregivers of adopted children arriving from countries with high or intermediate HAV rates

Havrix and Vaqta are 2 single antigen hepatitis A vaccines approved in the United States (See Tables 1 and 2). These are given as a 2 dose series with the second dose administered at least 6 months after the first. These vaccines are inactivated and can be administered with other immunizations. Also, the hepatitis A vaccines can be administered to immunocompromised patients.

Table 1: HAVRIX® Dosing and Schedule Information1

Age

Dose (ELISA units)*

Volume (mL)

Number of doses

Schedule (months)

12 months-18 years

720

0.5

2

0,6-12

>19 years

1,440

1

2

0,6-12

*Enzyme-linked immunosorbent assay units

Table 2: VAQTA® Dosing and Schedule Information1

Age

Dose (units)

Volume (mL)

Number of doses

Schedule (months)

12 months-18 years

25

0.5

2

0,6-18

>19 years

50

1

2

0,6-18

Vaccine adverse effects are rare but may include pain and soreness at the injection site, low-grade fever, headache, and tiredness.2 There is also a combination vaccine, Twinrix, that contains both HAV and hepatitis B virus antigens.

Individuals traveling or working in countries with high or intermediate HAV rates should be vaccinated or receive immune globulin (IG) prior to traveling. The first dose of the hepatitis A vaccine should be administered as soon as travel is considered. Travelers allergic to the vaccine component or who are < 12 months of age should receive a single dose of IG (0.02 mL/kg), which provides short term protection for up to 3 months.1 Individuals traveling for > 2 months should receive IG (0.06 mL/kg). Subsequently, administration must be repeated if the travel period exceeds 5 months.1

  • Postexposure prophylaxis can protect against HAV1

Individuals exposed to HAV who have not been previously vaccinated should be administered a single dose of Havrix or Vaqta or IG (0.02 mL/kg) as soon as possible, within 2 weeks after exposure. The vaccine is recommended over IG for healthy patients 12 months-40 years of age. Additionally, IG is preferred for individuals 41 years and older. Use IG for the following groups:

  • Children less than 12 months of age
  • Immunocompromised patients
  • Individuals with chronic liver disease
  • Patients allergic to the vaccine or a vaccine component.

References

  • Viral hepatitis-hepatitis A information. CDC website. https://www.cdc.gov/hepatitis/HAV/HAVfaq.htm#general. Accessed December 30, 2016.
  • Hepatitis A VIS. CDC website. https://www.cdc.gov/vaccines/hcp/vis/vis-statements/hep-a.html. Accessed December 30, 2016.