By Cat Holmes
University of Georgia
Cook those green onions. That’s the word from the U.S. Food and
Drug Administration and food safety experts following recent
hepatitis A virus outbreaks in Georgia, Tennessee, North
Carolina and Pennsylvania that have been associated with raw or
undercooked green onions.
With Americans eating more produce than ever, it’s important to
wash it thoroughly and cook it whenever possible.
“There has been a tremendous increase in fresh produce
consumption,” said Michael Doyle, director of the University of
Georgia Center for Food Safety and an international authority
on foodborne bacterial pathogens. “It’s doubled in the last 20
years.”
More people eating more fresh produce, however, has resulted in
more cases of illnesses linked to contaminated produce.
In the case of the recent hepatitis A virus outbreak in
Tennessee, the green onions were traced to Mexico. But Doyle
cautions against singling out Mexican produce.
“You don’t want to condemn all produce from Mexico,” he
said. “There are major U.S. growers with production farms in
Mexico and these operations are very controlled. Produce from
these fields is as safe as any grown in the United States.”
Where it comes from
Hepatitis A virus, like Norovirus, is always the result of
contamination by infected humans.
“The only reservoir of HAV is humans,” Doyle said. “The virus
is found in the stools of infected humans. Feces from carriers
of HAV can contaminate food and water.”
When large HAV outbreaks occur, it’s usually caused by a
restaurant food handler with poor hygienic practices, Doyle
said, or polluted water contaminating foods.
This highlights the importance of practicing good hygiene and
good food-handling practices: Wash your hands, and cook your
food.
Get cooking
The easiest way to avoid potential HAV exposure in green onions
is to cook them.
“Cooking is the best way to minimize the risk of HAV
infection,” Doyle said. “Washing won’t eliminate foodborne
pathogens, but it can bring the level down so that it doesn’t
cause problems. People who are severely immune-compromised
should only eat cooked produce.”
Freshly prepared salsa and green salads are often made with
green onions. When you are eating out at restaurants, the FDA
recommends that you specifically request that raw or lightly
cooked green onions not be added to your food.
Since contamination is typically on the surface, Doyle also
suggests peeling fruits and vegetables such as bananas, apples,
carrots when possible. In the case of iceberg lettuce or
cabbage, remove the outer two layers of leaves.
About hepatitis A
Hepatitis A infection takes an average of about a month to
appear, which means the symptoms can develop weeks after
exposure.
According to the Centers for Disease Control and Prevention,
adults are more likely to have symptoms than children.
Symptoms usually occur abruptly. They may include fever,
tiredness, loss of appetite, nausea, abdominal discomfort, dark
urine and jaundice (yellowing of the skin and eyes). Symptoms
usually last less than two months. A few people, though, are
ill for as long as six months. There is no chronic infection
with HAV.
Vaccines are available for long-term prevention of hepatitis A.
They’re not recommended for children 2 years old or younger.
According to the CDC Web site, the HAV vaccine was more widely
used in the late 1990s and the number of cases reached historic
lows.
Cat Holmes is a news editor for the University of Georgia
College of Agricultural and Environmental Sciences.
