In August 2015, the Texas Department of State Health Services received requests from 2 separate local health departments for postexposure prophylaxis recommendations for contacts of 2 nurses with confirmed HAV infection. In both nurses, symptomatic infections developed within days of each other; both nurses worked for the same pediatric home healthcare agency. The nurses did not have shared exposures other than 1 patient and had not been vaccinated for hepatitis A.

The shared patient was a 7-year-old who underwent multiorgan (liver, small bowel, and pancreas) transplantation because of megacystis microcolon intestinal hypoperistalsis syndrome, a rare congenital condition characterized by a largely dilated nonobstructed urinary bladder (megacystis), very small colon (microcolon), and decreased or absent intestinal movements (intestinal peristalsis). The transplantation occurred in December 2014.

This patient’s posttransplant course was complicated by intraabdominal abscesses, acute liver rejection, Epstein-Barr virus enteritis, cytomegalovirus infection, and lymphoproliferative disorder. The patient was discharged to home in March 2015 with an alanine aminotransferase (ALT) level of 49 IU/L (referemce 0–50 IU/L). By the following month, ALT had increased to 324 IU/L, and by June 2015, to 515 IU/L. During the time of ALT increase, the patient, who had a colostomy and ileostomy, also had increased stoma output. Because of worsening clinical symptoms, a liver biopsy was conducted on June 19, 2015; results showed features of moderate acute cellular rejection, as well as diffuse, lobular acute and chronic inflammation. On June 30, a repeat liver biopsy was performed because of persistent ALT elevation despite increased treatment for rejection.

The multi–visceral organ recipient had received 2 doses of hepatitis A vaccine, as part of routine childhood vaccinations, and was IgG HAV positive in 2013, indicating prior immunity against HAV, although the patient was immune suppressed after transplantation. Because of the other clinical conditions that could have explained the ALT elevation and gastrointestinal symptoms, HAV infection was initially not considered. When subsequent testing prompted by the infections in the recipient’s caregivers revealed the multi–visceral organ recipient was positive for HAV RNA, a laboratory and epidemiologic investigation focused on whether infection was due to recent fecal–oral transmission or from solid-organ transplantation. Available transplant-related specimens were tested to rule out transmission through transplantation.

The isolation of genetically identical HAV RNA sequences from the multi–visceral organ recipient and the organ donor indicates HAV infection was transmitted through organ transplantation, even though the index patient had earlier evidence of immunity. The 3 HCWs associated with this investigation most likely were infected by the traditional fecal–oral route. The infectious period of the multi–visceral organ recipient is also among the longest documented in a person infected with HAV, typically an acute disease (9).

Diagnosis in the multi–visceral organ recipient probably was delayed due to deferred testing because of concurrent conditions that provided alternative explanations for the recipient’s clinical presentation and history of prior HAV immunity. The patient had history of vaccination but immune suppression probably blunted antibody response. Symptomatic persons typically show elevated ALT levels that coincide with onset of clinical illness. The infected organ recipient had elevated ALT shortly after liver transplantation, but it coincided with other viral infections (Epstein-Barr virus and cytomegalovirus) and was later assumed to be related to possible acute liver rejection.

The process that results in prolonged courses of HAV infection is unknown (10). In contrast to hepatitis B and C viruses, HAV is not typically associated with a prolonged infectious carrier state (11). Nonetheless, this case report, and scant longitudinal studies in the literature, demonstrate the potential for ongoing transmission. In published longitudinal studies, HAV viremia persisted for median periods of 22–42 days in immunocompetent persons and 256–490 days in immunocompromised persons (11,12). Similar findings have been published of persistent viral shedding in feces with median days of detection after symptom onset of 81–127 days (11). The level and length of HAV infection and fecal shedding make the carrier a potential continuing infectious source of the virus, which occurred in this case.

Because the primary transmission of HAV is fecal–oral, it is not surprising that diarrhea or fecal incontinence leads to the spread of infection (13). Nosocomial outbreaks are uncommon because hygienic practices are generally adhered to more consistently when the patient is symptomatic enough to be hospitalized (14). The use of contact precautions is recommended for HCWs caring for patients with HAV who are diapered or incontinent (15). Because HCWs do not have increased prevalence of HAV infection and because nosocomial outbreaks of HAV are rare, hepatitis A vaccination is not mandatory for HCWs in the United States (16,17). In this case, the multi–visceral organ recipient’s ileostomy and colostomy output had increased, but it was difficult to determine whether these increases represented symptoms of HAV infection because her stoma output was typically described as a continuous liquid, even before hepatitis developed. Also, the home health nurses were spending 12 hours per shift inside the patient’s home, where they ate meals and shared space with the patient’s family, and thus were considered household contacts, which increased their risk for infection. Previous studies have shown that length of contact with an infected patient increases the attack rate of HCWs, and postexposure prophylaxis is recommended for household contacts of infected patients (14,16). The parents of the organ recipient were tested for HAV infection before the patient was determined to be the source. The mother’s test results indicated immunity to HAV, and the father was not HAV immune but received hepatitis vaccination at testing. Once the infection was detected, contact precautions were instituted during subsequent hospitalizations, the local health department recommended the patient’s home health nurses be fully vaccinated against HAV, and no further transmissions to HCWs were detected during the subsequent 8 months of continued viral shedding in the patient’s feces.

Transmission of HAV after blood transfusion has been established previously but has not been reported through organ transplantation (5). Organ procurement organizations typically complete a medical history questionnaire focusing on prior vaccinations, infections, and exposures to screen donors and recipients for multiple types of infection (18). Because of the acute nature of HAV infection, pretransplant testing is not routinely done, although hepatitis A vaccination of transplantation candidates is recommended (16). The multi–visceral organ recipient was vaccinated, but studies have shown loss of immunity to HAV after transplantation because of immunosuppression (19,20). The heart and kidney transplant recipients had evidence of immunity and probably were protected through previous vaccination. It is unknown whether the differences in immunosuppression and types of organs transplanted in the heart and kidney recipients were also factors in preventing HAV infection after transplantation in these persons.

In 2006, the Advisory Committee on Immunization Practices recommended routine hepatitis A vaccination for all children beginning at 12–23 months of age (16). Both inactivated whole-virus vaccines available in the United States are well tolerated and effective, showing serologic levels of protection for at least 17 years (21,22). In 2014, however, 2-dose vaccination coverage among children 19–35 months of age in the United States was only 57.5%, the lowest vaccine coverage for a complete vaccine series among the routine childhood vaccines (23). The 8-year-old organ donor in this report most likely was not vaccinated against HAV, and transmission to the recipient and HCWs could have been prevented had vaccination occurred.

Rapid communication between public health officials, physicians, transplant centers, and organ procurement organizations made locating and testing the other organ recipients in this investigation possible. Because of the low US incidence of HAV infection and typically brief self-limiting course of disease, an HAV-unvaccinated organ donor is unlikely to be acutely infected at death and transmit HAV to a patient. The acute nature of HAV infection, low population HAV infection rate, and low rate of HAV infection–associated hospitalization make universal vaccination of HCWs and pretransplant testing for patients impractical. Vaccination against hepatitis A of the organ donor at 12–23 months of age, as recommended by the Advisory Committee on Immunization Practices, most likely would have prevented infection of the multi–visceral organ recipient and exposed HCWs.