San Diego and Santa Cruz Counties are currently experiencing outbreaks of hepatitis A infection. Public health officials have also identified cases due to the same strain of hepatitis A virus (HAV) in other California jurisdictions, as well as Arizona and Utah. CDPH may identify additional outbreak jurisdictions in California.
CDPH determined transmission occurs person-to-person; no commercial product is identified as being contaminated. Current information indicates all homeless populations and persons using injection or non-injection illicit drugs are considered at risk of outbreaks if exposed to HAV.
Public health departments face difficulties in providing access to vaccination efforts to the homeless and illicit drug use populations; such persons receive episodic health care in emergency departments. Offering vaccination in this setting is crucial to improving the vaccination opportunities of at-risk persons.
In response this outbreak, CDPH recommends:
- Hospitals, particularly hospital emergency departments, should work with their local health departments to offer hepatitis A vaccines to all patients who are homeless, users of injection or non-injection illicit drugs, infected with hepatitis B or hepatitis C, or have other liver disease, e.g., alcoholic cirrhosis*.
- Screening for serological immunity prior to vaccination is not necessary; however, previous doses of the vaccine may be recorded in the California Immunization Registry (CAIR2) or your local immunization registry.
- Use standing orders/order sets to ensure vaccination of the at-risk population.
- Record vaccine doses administered in CAIR2 or your local immunization registry.
- Ensure all vaccines are stored and handled appropriately. †
- Hospitals must contact the local health department immediately during business hours (or 24/7 in San Diego) to report suspected hepatitis A infection in patients who are homeless and/or use injection or non-injection illicit drugs, while the patient is still in the facility, as this may be the only opportunity for public health to interview the patient. Hospitals should not test asymptomatic persons for hepatitis A infection.
- Hospitals should promptly report all confirmed HAV cases to the local health department and save the blood (serum and EDTA or citrate plasma) from hepatitis A serological testing.
- Hospitals in outbreak jurisdictions should:
- Offer the hepatitis A vaccine to health care personnel who have frequent close contact with patients who are homeless and/or use injection or non-injection illicit drugs.
- Ensure appropriate cleaning of restrooms frequented by persons who are homeless and/or use injection or non-injection illicit drugs. Environmental cleaning methods similar to those used for norovirus should be implemented.
Additional Information about the Vaccine
- The first dose of single-antigen hepatitis A vaccine appears to provide protection to more people than the first dose of the combined hepatitis A/hepatitis B (Twinrix®) vaccine (see Table 3, product insert). This apparent advantage disappears when the respective series are completed.
- Providers should consider short-term risks of exposure to HAV, the likelihood of follow-up to complete multi-dose immunization and the need for protection from hepatitis B when selecting vaccines for those at risk. Immunization against HAV with existing vaccine supplies should not be delayed to obtain a different formulation of vaccine.
- CDPH recommends hepatitis B vaccine for injection drug users who are not known to be immune. A complete vaccination series is needed for full protection.
- Persons who have been exposed to HAV in the prior 2 weeks who are not known to be immune should also receive hepatitis A vaccine and/or immune globulin.
- An emergency department, clinic or network pharmacy may provide hepatitis A vaccine to Medi-Cal patients (Fee-for-Service or Managed Care) without prior authorization.
- Hepatitis A vaccine for adults is reimbursable when billed with CPT-4 code 90632. When using code 90632, document medical necessity in the Remarks field (Box 80)/Additional Claim Information field (Box 19). In this situation, relevant conditions indicating medical necessity are:
- User of illicit injectable or non-injectable "street" drugs
- Chronic liver disease
- Residing in a high-risk community (in the current situation a homeless patient’s medical necessity would be residing in a high-risk community)
*HAV vaccine is routinely recommended for adults who:
- Want to be protected from hepatitis A
- Are traveling to countries that have high or intermediate levels of hepatitis A transmission (i.e., all except the U.S., Canada, Japan, Australia, New Zealand, and Western Europe).
- Are male and have sex with other males
- Use street drugs (injection and non-injection)
- Have a diagnosis of chronic liver disease, including hepatitis B and C
- Have a diagnosis of a clotting-factor disorder, such as hemophilia
- Anticipate close personal contact with an international adoptee from a country of high or intermediate endemicity during the first 60 days after the adoptee’s arrival in the United States.
- Are employed in a research laboratory requiring work with hepatitis A virus or hepatitis A-infected primates.
†Vaccine Storage and Handling Information
- Hepatitis A vaccine should be maintained at refrigerator temperature between 36°F and 46°F (2°C and 8°C). Manufacturer package inserts contain additional information.
- Monitor vaccine temperatures twice daily, paying close attention to CURRENT temperature (unit’s temperature now), as well as MIN/MAX temperatures (the coldest and warmest temperatures in the refrigerator since the last reading/thermometer reset).
- Vaccine exposure to temperatures outside the manufacturer’s recommended range may result in vaccine damage and loss of potency.
- Liquid vaccines that contain an aluminum adjuvant, such as hepatitis A vaccine, can permanently lose potency when exposed to a single freezing temperature event (0°C [32°F] or colder), regardless of exposure time. Therefore, immediate action must be taken to prevent further use of vaccine that has been exposed to an out of range temperature until a determination of vaccine viability has been provided by the vaccine manufacturer.
- The Advisory Committee on Immunization Practices’ General Recommendations on Immunization state, "Vaccine exposed to inappropriate temperatures that is inadvertently administered should generally be repeated."
- For complete information on best practices and recommendations for vaccine storage, please refer to Centers for Disease Control and Prevention’s (CDC) Vaccine Storage and Handling Recommendations and Guidelines and Vaccine Storage and Handling Toolkit.
If you have any questions about hepatitis A infection or vaccine, please contact Kathleen Harriman at: (510) 620-3767, or by email at: Kathleen.Harriman@cdph.ca.gov. Thank you for your efforts to protect Californians from hepatitis A infection.
Original signed by Jean Iacino