About Hepatitis A Food Poisoning

Hepatitis A is the only common vaccine-preventable foodborne disease in the United States (Fiore, 2004).  It is one of five human hepatitis viruses that primarily infect the human liver and cause human illness.  Unlike hepatitis B and C, hepatitis A doesn’t develop into chronic hepatitis or cirrhosis, which are both potentially fatal conditions; however, infection with the hepatitis A virus (HAV) can still lead to acute liver failure and death.

Hepatitis A is much more common in countries with underdeveloped sanitation systems. This includes most of the world: an increased transmission rate is seen in all countries other than the United States, Canada, Japan, Australia, New Zealand, and the countries of Western Europe. Nevertheless, it continues to occur in the United States; approximately one-third of the population has been previously infected with HAV (Fiore, 2004; Centers for Disease Control and Prevention [CDC], 2009a). Each year, approximately 30,000 to 50,000 cases of hepatitis A occur in the United States. Historically, acute hepatitis A rates have varied cyclically, with nationwide increases every 10 to 15 years. The national rate of HAV infections has declined steadily since the last peak in 1995. Although the national incidence (1.0 case per 100,000 population) of hepatitis A was the lowest ever recorded in 2007, it is estimated that 25,000 new infections occurred that year after asymptomatic infection and underreporting were taken into account. Although the rates of HAV infection have declined over the years, rates are twice as high among American Indians/Alaskan Natives (AIAN) and Hispanics compared to non-Hispanic Whites in the United States (Rawls & Vega, 2005). Rates among AIAN have decreased dramatically, though, coincident with the implementation of routine hepatitis A vaccination of AIAN children, both in urban and rural communities (Bialek et al., 2004).


In 2007, a total of 2,979 acute symptomatic cases of hepatitis A were reported (CDC, 2009b). Among the 1,047 cases with available information regarding foodborne or waterborne exposure, 6.5% were found to be foodborne or waterborne related, about one-third the proportion reported at the last peak in 2003. However, 2500 cases remained without known risk factors.

Estimates of the annual direct and indirect costs of hepatitis A in the United States have ranged from $300 million to $488.8 million in 1997 dollars (CDC, 2007). In a Spokane, Washington study, the combined direct and indirect costs for each case of hepatitis A from all sources ranged from $2892 to $3837 (Bownds et al., 2003). In an Ohio study, the estimated cost per case of foodborne illness due to HAV in 2007 was $10,000, including medical and drug costs, deaths, and quality of life (Scharff et al., 2009). Nationwide, adults who become ill miss an average of 27 work days per illness and 11 to 22 percent of those infected are hospitalized (CDC, 2009c). These are avoidable illnesses, since 21st Century medicine and the advent of hepatitis A vaccine have rendered hepatitis A infections totally preventable.

How is Hepatitis A transmitted?

Hepatitis A is a communicable (or contagious) disease that spreads from person to person. It is transmitted by the “fecal – oral route,” generally from person-to-person, or via contaminated food or water. Food-related outbreaks are usually associated with contamination of food during preparation by an HAV-infected food handler (CDC, 2009c). The food handler is generally not ill: the peak time of infectivity (that is, when the most virus is present in the stool of an infectious individual) occurs during the 2 weeks before illness begins. Fresh produce contaminated during cultivation, harvesting, processing, and distribution has also been a source of hepatitis A (Fiore, 2004). In 1997, frozen strawberries were determined to be the source of a hepatitis A outbreak in five states (Hutin, et al., 1999), and in 2003, fresh green onions were identified as the source of a hepatitis A outbreak traced to consumption of food at a Pennsylvania restaurant (Wheeler, et al., 2005). Other produce, such as blueberries and lettuce, has been associated with hepatitis A outbreaks in the U.S. as well as other developed countries (Butot et al., 2008; Calder et al., 2003).

HAV is relatively stable and can survive for several hours on fingertips and hands and up to two months on dry surfaces, but can be inactivated by heating to 185°F (85°C) or higher for one minute or disinfecting surfaces with a 1:100 dilution of sodium hypochlorite (household bleach) in tap water (Advisory Committee on Immunization Practices [ACIP], 2006; CDC, 2009c; Todd et al., 2009). However, HAV can still be spread from cooked food if it is contaminated after cooking.

Although ingestion of contaminated food is a common means of spread for hepatitis A, it may also be spread by household contact among families or roommates, sexual contact, by the ingestion of contaminated water or shellfish (like oysters), and by direct inoculation from persons sharing illicit drugs. Children often have asymptomatic or unrecognized infections and can pass the virus through ordinary play, unknown to their parents, who may later become infected from contact with their children.