8/17/2023 0 Comments Hepatitis a transmission sexually![]() A combined hepatitis A and hepatitis B vaccine (Twinrix) has been developed and licensed for use as a 3-dose series for adults aged ≥18 years at risk for HAV or HBV infections. Anti-HAV persistence of >20 years was demonstrated among immunocompetent adults vaccinated with a 2-dose hepatitis A schedule as adults ( 1303, 1305). A study of Alaska Natives demonstrated that seropositivity for hepatitis A persists for >20 years after completing 2-dose vaccination at age 12–21 months ( 1302). These vaccines are available for eligible children and adolescents aged 40 years ( 1302– 1304). Two monovalent vaccines (Havrix and Vaqta are approved by FDA for persons aged ≥12 months (Table 3). Hepatitis A vaccines are prepared from formalin-inactivated, cell-culture–derived HAV. Vaccination is the most effective means of preventing HAV transmission among persons at risk for infection (e.g., MSM, injecting drug users, and persons with chronic liver disease) who did not receive hepatitis A vaccination during childhood. Medications that might cause liver damage or are metabolized by the liver should be used with caution among persons with HAV infection. Hospitalization might be necessary for patients who become dehydrated because of nausea and vomiting and is crucial for patients with signs or symptoms of acute liver failure. Patients with acute HAV infection usually require only supportive care, with no restrictions in diet or activity. Although usually not sensitive enough to detect the low level of protective antibody after vaccination, anti-HAV tests also might be positive after hepatitis A vaccination. A positive test for total anti-HAV indicates immunity to HAV infection but does not differentiate current from previous HAV infection. Presence of IgM antibody to HAV is diagnostic of acute HAV infection. Diagnostic Considerationsĭiagnosis of HAV infection cannot be made on a clinical basis alone but requires serologic testing. Other infection sources identified in the United States include MSM persons who use injecting drugs sexual and household contacts those experiencing homelessness international travelers those with children attending a nursery, childcare, or preschool and persons working in such settings ( 13, 372). Among cases with a risk factor identified, a recognized foodborne or waterborne outbreak was the most commonly identified risk (49.6%). In the United States, of the hepatitis A cases accompanied by risk information, a particular risk was identified among only 23.8% ( 13, 372). Transmission by saliva has not been demonstrated. Although viremia occurs early during infection and can persist for weeks after symptom onset, bloodborne transmission of HAV is uncommon ( 1299). Transmission of HAV during sexual activity probably results from fecal-oral contact. HAV infection is primarily transmitted by the fecal-oral route, by either person-to-person contact or through consumption of contaminated food or water ( 1298). Antibody produced in response to HAV infection persists for life and confers protection against reinfection ( 1297). The risk for symptomatic infection is directly related to age, with approximately 70% of adults having symptoms compatible with acute viral hepatitis and the majority of children having either asymptomatic or unrecognized infection. Acute liver failure from hepatitis A is rare (overall case-fatality rate: 0.5%). However, approximately 10% of patients experience a relapse of symptoms during the 6 months after acute illness. HAV infection produces a self-limited disease that does not result in chronic infection or chronic liver disease. HAV replicates in the liver and is shed in high concentrations in feces from 2–3 weeks before to 1 week after the onset of clinical illness. HAV infection has an incubation period of approximately 28 days (range: 15–50 days) ( 1296).
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |