Hepatitis A: Increasingly Rare but Entirely Possible

Hepatitis A is a viral infection that’s transmitted via the fecal-oral route and causes an acute hepatitis. It is highly infectious and most likely to occur in injection drug abusers or men who have sex with men. However, it can also be transmitted through contaminated water and food, under conditions of poor sanitation, and in crowded living conditions. In the United States, public health officials see community outbreaks from time time—usually associated with childcare centers. Conversely, hepatitis A infection is endemic in Africa, Asia, Central and South America, and Eastern Europe.

Many health care providers do not understand fecal-oral contamination. They think, “This doesn't happen here. We wash our hands and practice good hygiene.”

While fecal-oral contamination often occurs in places where sanitation is poor, it can occur in less likely locations if:

• water is treated insufficiently
• fecal matter sits in the open
• gardeners work in contaminated soil or compost
• microscopic quantities of fecal matter transfer from a person who has just changed a baby’s diaper or petted an animal
• flies visit a toilet or laundry basket and then land on food
• people swim in community swimming pools
• sex transfers minute quantities of feces

Hepatitis A is generally mild and self-limiting, but it has the potential to cause morbidity and mortality, especially when it occurs among susceptible older adults. Children—among whom approximately 90% have been infected by age 10 years if they live in areas with poor sanitation and living conditions—usually don’t develop symptoms, while adults who contract hepatitis A later in life usually do. Simply put, increasing age is associated with a greater likelihood of symptomatic hepatitis.

Patients who contract symptomatic hepatitis A often lose their appetite and energy and may experience vomiting, fever, abdominal pain, and, in some cases, jaundice. Patients may report a dark, amber-colored urine or light-colored feces. Many people confuse hepatitis A’s symptoms with those of influenza and do not seek care. Should this disease appear in its fulminant form, it is considered life-threatening.

Outbreaks and Endemic Incidence

American public health officials see temporary increases in hepatitis A infections and outbreaks approximately every 10 to 15 years. Between those times, they estimate that approximately 21,000 Americans contract hepatitis A annually. Hepatitis A is vaccine-preventable, and the CDC first recommended routine vaccination for children in the mid-1990s. Since then, the CDC’s recommendations have grown to include additional groups of Americans. Baseline rates of hepatitis A have decreased significantly.

Increases in cases of hepatitis A in 2012 and 2013 indicate that this virus may be mutating. Most cases of hepatitis A have been traced to travel outside the United States. However, a significant number of cases seem to be related to contaminated food. Clinician should note that imports of fresh and frozen fruits, vegetables, and shellfish from countries that have endemic hepatitis A have increased the risk of hepatitis A transmission. A 2016 outbreak in the United States was traced back to frozen strawberries imported from Egypt. Similarly, the state of Hawaii experienced an outbreak that was eventually traced to raw scallops originating in the Philippines.

Patients who develop hepatitis A pursuant to a restaurant visit generally develop symptoms between 2 and 6 weeks after exposure. This makes it particularly difficult to identify others who may have dined at the same establishment or purchased food at the same vendor. Should patients present with hepatitis A symptoms, retail health clinicians should confirm the diagnosis with serologic (serum) testing unless the patient is a household contact of a confirmed case. Blood work will reveal an elevated ALT/AST in many cases. They must also be prepared to treat symptoms.

Treatment

Supportive care is appropriate. Most patients present with an acute syndrome and may need antiemetics for nausea and vomiting. They should force fluids or be hospitalized if the dehydration is severe. During the acute stage of this illness, patients should rest and engage in activity only as they feel well enough to do so. They should stay home from work, especially if they work in the food or hospitality industries. Clinicians should advise patients to rest their livers by avoiding alcoholic beverages and taking acetaminophen only when absolutely necessary and never exceeding recommended doses. Clinicians should consider hospitalizing the rare patient with fulminant hepatitis. Most cases will resolve on their own over a period of weeks to 6 months.

Having hepatitis A as a child confers lifelong immunity. Patients who develop hepatitis A later in life also develop immunity to future infection. However, they may be at risk for hepatitis B, and retail health care clinicians should recommend patients be vaccinated for hepatitis B. The patients’ contacts can receive post-exposure prophylaxis consisting of the first dose of the hepatitis A vaccine or immune globulin. Patients and their contacts should also be reminded of good hygiene, particularly handwashing and food preparation.

Hepatitis A is a reportable disease in the United States so that public health officials can attempt to find the source of exposure.

Public health officials hope to eradicate hepatitis A in the United States. The best way to do this is to promote vaccination, especially among adults who aged out of pediatric vaccinations before 1996.

Recommended Reading

Viral hepatitis; Hepatitis A. CDC website. cdc.gov/hepatitis/HAV/index.htm. Accessed April 30, 2017.

Murphy TV, Denniston MM, Hill HA, et al. Progress toward eliminating hepatitis a disease in the United States. MMWR Suppl. 2016;65(1):29-41.