Public health officials have suspected for weeks that a hepatitis A outbreak among 19 workers on a San Marino movie set might be linked to lettuce that came from a prominent Northern California grower.
But a contractor for the San Benito County company, Pride of San Juan, said this week that it had never been notified of the outbreak, let alone investigated as a possible source of tainted produce.
For The Record
Los Angeles Times Thursday February 16, 2006 Home Edition Main News Part A Page 2 National Desk 3 inches; 111 words Type of Material: Correction
Hepatitis A -- An article in Friday's California section about a hepatitis A outbreak among workers at a San Marino movie set did not fully describe the reasoning behind health officials' decision not to trace possibly contaminated lettuce to the farm on which it was grown. State officials said that there was little likelihood of determining for certain whether there was a link between the lettuce and the outbreak, in part because so much time had elapsed between when the infections occurred and when they were reported. In addition, the state found no evidence that lettuce was an ongoing or widespread source of hepatitis A in Los Angeles County or elsewhere.
"This is news to us," said Karl Kolb, the contractor who handles food safety issues for the company. "No one has talked about this at all."
State and Los Angeles County health officials acknowledge that they halted their inquiry after finding no evidence of contamination by the caterer or distributor. A full-scale "trace-back" to the grower was not worthwhile, they said, because it would not have explained the vast majority of the more than 300 hepatitis A cases seen throughout the county in recent months.
Investigating the source of a food believed to be contaminated is common practice in major outbreaks, public health experts say. The state in the past has pursued extensive inquiries examining every point on the supply chain -- servers, distributors, transporters and growers -- to determine how a product may have become tainted.
Health officials still do not know when or how the mixed baby greens served Oct. 3 on the Huntington Botanical Gardens set of the movie "The Good German," starring George Clooney and Cate Blanchett, may have become contaminated. In fact, they are at a loss to explain the overall surge in hepatitis A cases countywide last fall.
On the set, the salad was served by Silver Grill Catering of North Hollywood, which said it had purchased the sealed, pre-washed lettuce through a distributor, Soleil Produce of Los Angeles. Invoices show that Soleil purchased the sealed bags from Pride of San Juan, based in San Juan Bautista, near San Jose.
Pride of San Juan describes itself as a gourmet produce supplier. It produces the brand "Emeril's Gourmet Produce" in association with renowned chef Emeril Lagasse. The company's website says it is "committed to food safety and our customers. The possibility of product contamination ... [is] something we at Pride of San Juan work at every day to avoid."
Pride of San Juan officials said the company had never been linked to a food-borne illness.
"It is beyond my belief that we could have been the source," said Howard Holt, who heads Pride of San Juan's processing plant operations.
By mid-November, the county health department had identified the lettuce mix as a probable culprit in the movie-set outbreak and asked state health authorities for a formal trace-back to the farm that grew it, documents show.
In December, the state quietly suggested discontinuing the probe, and the county agreed. Officials later explained that they could not link lettuce to other hepatitis A illnesses countywide.
"We did not have a unifying hypothesis for all Los Angeles County cases, so going to the source of the production of lettuce [served on the movie set] would not have been a fruitful ... endeavor," said Dr. Laurene Mascola, director of the county's acute communicable disease control unit.
The county briefly looked into the possibility that red lettuce from a different grower or jerked chicken might have been implicated in the Silver Grill outbreak but determined that was unlikely.
After years of declining numbers, the county saw a significant jump in hepatitis A cases starting in August. The county had been averaging nine cases a month, but from Aug. 1 to Dec. 31, the average spiked to 71, peaking in November with 115.
Hepatitis A is a liver disease caused by a virus. It is usually spread through oral contact with fecal matter and can be spread by person-to-person contact or by ingesting tainted food or water.
About 7,500 people in the United States fell ill with the disease in 2003, the latest year for which figures are available. Although most recover with medical attention, the virus kills about 100 each year nationally. A vaccine is available for the disease.
No one has died as a result of any of the county's recent infections, health officials said.
Public health experts said the question of whether to do a trace-back on contaminated food depended on the strength of the evidence linking a product to an outbreak.
"Someone needs to decide whether there's going to be enough value gained in doing so," said Dr. Eric Frykman, health officer for San Bernardino County. "I don't know where anyone's cutoff is."
Ongoing illness would be one impetus for considering a full trace-back, he said.
But such investigations are time-consuming and often lead to inconclusive results, said George Chang, a UC Berkeley professor of food microbiology.
"It's only once in a long time that you really catch someone with a smoking gun," Chang said. "Most of the time, the investigations end in dead-ends."