In fight against outbreaks, green onions present layered resistance

Penn Live ^ | 11/14/2003 | DAN LEWERENZ

[lelio]

HARRISBURG, Pa. (AP) — While investigators work to pinpoint the cause of a western Pennsylvania hepatitis A outbreak that has killed three people and sickened more than 490, some food safety experts say green onions are particularly hard to keep clean.

Luke LaBorde, assistant professor of food science at Penn State University, said Friday that the way green onions are grown and eaten, even the structure of the onion itself, can make them particularly likely to transmit diseases like hepatitis A.

A study by the U.S. Food and Drug Administration found that green onions were more likely to be contaminated with Shigella bacteria than many other vegetables. Shigella, like hepatitis A, is most often transmitted when contaminated fecal matter comes into contact with food and is eaten.

FDA spokeswoman Kimberly Rawlings said she didn't know of any studies that showed green onions were more likely to carry hepatitis A than other produce.

Green onions stay low to the ground, LaBorde said, with the bulb below the ground and the shoots sticking up. If human or animal waste is used as fertilizer, or if contaminated water is used to irrigate the field, the virus can easily work its way down into the plant.

And once the plant is contaminated, it's almost impossible to clean because of the onion's many layers, said Dr. Ronnie Martin, chair of family medicine at Nova Southeastern University College of Osteopathic Medicine in Fort Lauderdale, Fla.

"If I contaminated a large field of green onions, and it got down inside the top of that growing onion, I would almost have to slice down each one of those layers and wash the whole thing inside and out," Martin said.

Martin said the virus can be killed by thoroughly cooking food, but green onions often are eaten raw or only lightly cooked.

But other than cooking or washing food, little can be done to fight contamination, LaBorde said.

"A lot of people are working on ways to decontaminate food, but it's so tough," LaBorde said. "There are so many nooks and crannies. It's like looking in the Grand Canyon for a person. There's too many places for them to hide."

The hepatitis A outbreak in Beaver County is thought to be the nation's largest on record. The Chi-Chi's restaurant at the Beaver Valley Mall in Monaca has been shut down, and the restaurant chain removed green onions from kitchens at all its 100 locations, said Bill Zavertnik, chief operating officer of the Louisville, Ky.-based company.

In September, about 280 people in Georgia and Tennessee were sickened by contaminated green onions, including 210 people who ate at restaurants in the Atlanta area.

[lelio]

Dang, I like in the Red Zone of WA. Woo hoo, 48 out of 100k Klickitat county! 73 in Yakima! Just try and top those numbers.

I didn't know there was a Chi-Chi's up here. Most Mexican restaurants around here are small mom and pops. In fact, we just got an Olive Garden. Odd that we don't have that many chain restaurants when Seattle gave the world Starbucks.

[EggsAckley]

Wow! That map is truly disturbing.

[FITZ]

I live in a red zone --- I'm not even that afraid of Hepatitis A because I've probably had it. Most of the time you don't die --- maybe it's dose dependent too, if you just get exposed to the virus a little at a time, you would just build up immunity I think.

[EggsAckley]

More on Chi Chi's here.

[FITZ]

I think it's probably more dangerous to those living in the white zones who have no immunity to this disease. As more and more of Mexico moves up into those areas, people will be exposed to more diseases they have no resistance to -- but luckily there is a vaccine for Hepatitis A.

[Joe Hadenuf]

We live in Texas & we eat out & cook Tex-Mex regularly. There is/was a Chi-Chi's here but the only one we have ever eaten in, is in Seattle.

Last time we were in Texas, we were eating at some Mexican restaurant outside Dallas.

My wife looked up at the lighting overhead, she jumped out of the booth and pointed at the ceiling. We could clearly see a silhouetted rat walking across the plastic lighting panel on the ceiling.

None of the people working their could speak English, except the cashier, who spoke very little English.

GAG! We left and one of the people behind the counter acted pissed off. I pulled out my bic lighter, lit it, stuck it in his face and pointed at the damn floor.

[DumpsterDiver]

ping

[The Duke]

"Geen onions" = scapegoats de-jour!

[cmsgop]

when contaminated fecal matter........

Ewwwwwwwwww!

[Ditter]

>>>>>none of the people working there could speak English>>>>>>
Hey you found the real deal. Ever been to Mexico? I don't understand the part about the lighter? Were you threatning to burn the place down?

[Willie Green]

As more and more of Mexico moves up into those areas, people will be exposed to more diseases they have no resistance to -- but luckily there is a vaccine for Hepatitis A.

There's no doubt that illegal immigrants bypass health officials and spread infectious disease.

But don't forget, it was only 1997 when 236 people in Michigan ALSO contracted Hepatitis A from Mexican NAFTA strawberries that were sold improperly to the school lunch program. (source)

I'm interested in knowing where Chi-Chi's gets their green onions.

[Ditter]

Did you hurry back to California where everything is perfect?

BTW I doubt if that is the first time you have eaten at a restaurant that had rats, just the first time you saw one.

[FITZ]

California has more red counties --- >20 hepatitis A cases a year than Texas where there are actually some white < 5 cases a year counties --- some white counties where there are no people though.

[FITZ]

It's likely ---thanks to NAFTA that the green onions came from Mexico --- this is from another Hepatitis A outbreak in Ohio:


http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11262211&dopt=Abstract

An outbreak of hepatitis A associated with green onions.

Dentinger CM, Bower WA, Nainan OV, Cotter SM, Myers G, Dubusky LM, Fowler S, Salehi ED, Bell BP.

Hepatitis Branch, Centers for Disease Control and Prevention, 1600 Clifton Road, MS G-37, Atlanta, GA 30333, USA. cgd1@cdc.gov

Forty-three cases of serologically confirmed hepatitis A occurred among individuals who ate at restaurant A in Ohio in 1998. Serum samples from all restaurant A employees who worked during the exposure period were negative for IgM antibodies to hepatitis A virus (HAV). A matched case-control study determined that foods containing green onions, which were eaten by 38 (95%) of 40 case patients compared with 30 (50%) of 60 control subjects, were associated with illness (matched odds ratio, 12.7; 95% confidence interval, 2.6-60.8). Genetic sequences of viral isolates from 14 case patients were identical to each other and to those of viral isolates from 3 patients with cases of hepatitis A acquired in Mexico. Although the implicated green onions, which could have come from one of 2 Mexican farms or from a Californian farm, were widely distributed, no additional green onion-associated cases were detected. More sensitive methods are needed to detect foodborne hepatitis A. A better understanding of how HAV might contaminate raw produce would aid in developing prevention strategies.

[tgslTakoma]

Isn't Chi Chi's a Mexican restaurant? I can't think of once single Mexican dish that calls for green onions. It must have been used as garnish.

Salsa? I use green onions in mine. But I wash them first.

[null and void]

Yes, Chi Chi's is a chain mexican restaurant. I actually thought they went out of business several years ago.

They may not survive the publicity from this outbreak.

[sarcasm]

TRANSMISSION

• HAV is found in the stool (feces) of persons with hepatitis A. 
• HAV is usually spread from person to person by putting something in the mouth (even though it may look clean) that has been contaminated with the stool of a person with hepatitis A. 

[Atlas Sneezed]

Here's the link to that map for those who want more detailed info:

http://www.cdc.gov/ncidod/diseases/hepatitis/a/vax/index.htm

[Atlas Sneezed]

hepatitis A, is most often transmitted when contaminated fecal matter comes into contact with food and is eaten.

---

I'm not even that crazy about UNcontaminated fecal matter in my food.

[4.1O dana super trac pak]

I would assume a TB map would look about the same.