In young children, hepatitis A is usually asymptomatic. So a childcare facility (CCF) in Ireland surprised by an outbreak of hepatitis A that infected 7 adults and 5 children, hospitalizing 6 of the adults. By the time the investigation and interventions were over, > 554 contacts had been followed up, and it had all cost > €45,000 ($53,000).
The outbreak was traced to a man with hepatitis A whose child had been unwell for 3 weeks with fever, fatigue, abdominal pain, diarrhea, pale stools, and possible jaundice. The child (and an infected cousin) attended a local CCF but because several other cases seemed to be limited to the family and their friends, no one immediately considered the CCF as a possible source of infection. However, approximately 10 days after the first 2 cases were reported, an outbreak was officially declared.
At the time, 93 children were attending the CCF. All 7 adults were household contacts of children in the CCF. None of the 23-member CCF staff developed symptoms of hepatitis A.
As many as 70% of infections are asymptomatic in children under age 6, the researchers note, but that group is often a source of transmission due to suboptimal hygiene. Transmission is usually fecal-oral and person-to-person. Although the initial source of outbreak was not identified, the subsequent transmission suggested person-to-person spread. The researchers say the distribution of cases suggests that the transmission probably happened in the school, with asymptomatic children infecting their families, highlighting the fact that symptomatic cases of hepatitis A only represent a portion of the cases in an outbreak.
A preschool inspection report that preceded the outbreak highlighted deficiencies in the staff’s handwashing practices. An infection control audit undertaken because of the outbreak found a number of deficits, including lack of foot-operated bins and the use of cloth covers on furnishings rather than waterproof material. Medical expenses, including hospitalization, serology, and vaccine, cost between €43,400 - €47, 400 ($51,000 - $56,000).
The researchers say the delayed notification to public health of the first case probably contributed to the extent of the outbreak. Medical professionals, they note, should be aware that although uncommon, hepatitis A still occurs. Prompt recognition and notification can mitigate the significant morbidity associated with the infection.
O'Connor L, McGovern E, O'Meara M, et al. Epidemiol Infect. 2018;146(6):705-711.