How Safe is Your Food?

Inconsistent reporting of foodborne illnesses among states leaves large portions of the country vulnerable to the spread of potentially deadly outbreaks before health officials can identify their causes and recall contaminated foods.

Since 2006, salmonella outbreaks from products such as eggs, cantaloupe and turkey burgers have sickened at least 6,000 people, resulting in more than 700 hospitalizations and 11 deaths, according to the U.S. Centers for Disease Control and Prevention. (Related story: Salmonella Outbreak Traced to Cantaloupes)

A News21 analysis of salmonella reporting practices found that differences across the country put residents of the worst-performing states at risk and undermine national outbreak surveillance by placing disproportionate responsibility on smaller states.

California, Texas, Florida and Illinois make up more than 30 percent of the U.S. population, but they contribute 15 percent to national salmonella outbreak surveillance. Meanwhile, Massachusetts and Missouri comprise 4 percent of the population and contribute nearly 9 percent to surveillance.

Disease reporting relies on highly variable state requirements. States like Colorado and Alabama that allow up to a week to submit a report for many illnesses, including salmonella and E. coli, may take longer to learn about an outbreak than states with more stringent requirements.

Outbreak Tests States

In the summer of 2008, one of the biggest and most widespread outbreaks in American history tested surveillance measures in 43 states and exposed weaknesses in the nation’s ability to identify and respond to outbreaks.

When it was over, salmonella-tainted jalapeno and serrano peppers had left two men dead in Texas, and around the country put 308 people in hospitals and made at least 1,500 others across the country sick enough to seek medical attention.

In large outbreaks, underperforming states prevent efficient responses and rely on the surveillance of other states. The same is true in smaller outbreaks; some of these elude surveillance entirely.

“There are multistate outbreaks out there that we don’t recognize and we don’t know about,” said Dr. Tim Jones, state epidemiologist for the Tennessee Department of Health.

National outbreak surveillance depends on the collaboration of 2,800 state and local health departments subject to at least 50 different reporting requirements.

In some states, reports from doctors and hospitals go directly to the state health department, which handles large-scale outbreak surveillance. Reporting in bigger states is often more fragmented, with reports going to largely independent local health departments, which then report to the state.

For salmonella, E. coli and other bacterial illnesses, requirements for reporting can also include the submission of what is called an isolate to the state health department, which can be tested to identify outbreaks.

In the same way miners extract metal from certain rocks, laboratories can extract a salmonella isolate from a patient’s stool sample.

Genetic Fingerprints

On May 22, 2008, the New Mexico Department of Health performed high-tech testing on isolates from four salmonella victims and identified the same genetic “fingerprint” on each of them: they were part of the same outbreak.

The New Mexico state laboratory uploaded the test results to a national database known as PulseNet. The next day, health officials in Texas and Colorado used the database to match fingerprints of local cases with those in New Mexico, proving they were associated with the outbreak.

Though PulseNet can identify local outbreaks, the network specializes in discovering widespread outbreaks associated with “industrial contamination events,” where the food is infected in the supply chain before reaching grocery stores and restaurants, said Dr. Ian Williams, chief of the CDC’s outbreak response and prevention branch.

These outbreaks often result in a handful of reported cases in multiple states. Without PulseNet connecting the dots, epidemiologists have few leads to investigate the source of illness.

“PulseNet is the engine that finds [multistate] outbreaks,” Williams said, “and my group is the engine that investigates the outbreaks.”

Though the CDC coordinates investigations when these multistate outbreaks occur, it can only “provide guidelines and recommendations” as a non-regulatory agency, Williams said. Without a federal standard, each state has a unique set of disease-reporting requirements and practices.

For diseases that require reporting to the health department, the urgency and speed of response are at the discretion of each state.

In eight states, health departments must be notified immediately about cases of E. coli O157, which can cause kidney failure and death from eating contaminated foods, including raw milk, meats and vegetables. Seven states allow a week, the longest timeframe in the country, to submit the same report.

The breakdown between stringent and lax reporting requirements among states holds true for most illnesses, provided that requirements exist at all. CDC recommends reporting for 20 foodborne illnesses, but fewer than half of the states require reporting for all of them.

Though every state requires reporting for salmonella, 12 states and Washington, D.C., do not require the submission of isolates to the state public health laboratory.

As the most populous state without the requirement, Texas received the third fewest isolates for its cases in the country before the 2008 hot pepper outbreak. Its contributions to national surveillance through PulseNet would be proportional for a state with 8 million fewer people.

By June 2, 2008, Texas reported the most cases of the hot pepper outbreak in the country. The Texas Department of State Health Services acknowledged the need to increase surveillance.

“We sent out a letter to all the clinical labs in the state and we asked them to please submit all salmonella isolates to the state lab,” said Dr. Linda Gaul, the foodborne epidemiologist for the Texas Department of State Health Services.

By simply asking, Texas received “twice as many isolates” for the rest of the outbreak, Gaul said. Over the next two months, the lab tested more than 1,200 isolates. In all of 2007, the state performed 1,835 of these tests.

By June 20, 2008, the number of cases reported in Texas doubled as a result of improved surveillance, according to CDC. Of 552 people sickened across the country, 264 were in Texas.

To begin the outbreak investigation process, epidemiologists interview victims about what they ate in the week before they got sick.

“It’s very difficult to [find the cause of an outbreak] from a single case,” said Dr. David Acheson, former associate commissioner for foods in the U.S. Food and Drug Administration. “Because you’ve got one person’s memory and they say, ‘Well, I usually buy my tomatoes at Safeway,’ but unbeknownst to them, that week they stopped at a Food Lion.”

Clusters of Clues

Localized groups of related illnesses called clusters offer epidemiologists clues. By interviewing victims of clusters, investigators may learn whether they all ate at the same restaurant or bought a certain food from the same grocery store.

Clusters are difficult to investigate when too much time passes between the illness and the interview. A survey conducted by the Council for State and Territorial Epidemiologists, an organization of public health epidemiologists, found that “delayed notification from reporting sources was the most common barrier to investigation of foodborne…illness outbreaks.”

“If I line up six people and say, ‘Tell me what you ate a month ago,’ we’re going to have trouble figuring that out,” said the CDC’s Williams.

The time between getting sick, seeing a doctor, reporting the illness and testing isolates allowed two weeks to pass for more than half of the illnesses before they were identified as part of the hot pepper outbreak. From there, the speed of response and success of the investigation depend on a state’s health department.

“Minnesota is often the first out of the gate with the answer and that, in my opinion, is driven heavily by the fact that they move things through really quickly,” said Acheson. “If there were a barometer of how quick to do it, they’d be…the poster child.”

On June 23, 2008, the Minnesota Department of Health identified its first case of the hot pepper outbreak, which proved to be part of a cluster. Fifteen days later it had “unequivocally implicated jalapenos,” according to a congressional testimony by Dr. Kirk Smith, state epidemiologist in Minnesota.

Texas reported the same results earlier that week – more than a month after its first cases in late May – taking more than twice the time to reach the same conclusion.

On July 9, 2008 with evidence mounting, the CDC issued a nationwide alert advising consumers to avoid jalapeno and serrano peppers, following indications that tomatoes played a role early in the outbreak.

The News21 analysis found that Texas experienced significant underreporting of salmonella isolates before the hot pepper outbreak, handicapping its ability to identify clusters and respond to outbreaks.

With nearly 8 percent of the country’s population, Texas provided 5 percent of the nation’s salmonella surveillance through PulseNet between 2001 and 2007.

Over that same time, Texas reported the fourth fewest salmonella outbreaks per 100,000 people, suggesting outbreaks went unidentified or unreported more frequently in Texas than in 46 other states.

These underreporting practices characterized Texas’ salmonella surveillance before the hot pepper outbreak. As it spent the first weeks of the investigation relying on data from insufficient reporting, the outbreak continued to spread.

When it was over, the outbreak had sickened 1500 people in 43 states,  Washington, D.C., and Canada, hospitalizing 308 and resulting in two deaths.

Since the outbreak, Texas has continued to request that all isolates be submitted to the state lab and increased its contribution to national outbreak surveillance to a level more proportional to population.

Stricter Reporting

State health officials are discussing how to include mandatory isolate submission for salmonella in Texas’ disease reporting requirements, Gaul said.

If the requirement is added, Florida would replace Texas as the most populous state without mandatory isolate submission for salmonella.

Since 1998, the Florida Department of Health has received isolates for less than 20 percent of its cases, the lowest percentage in the country and less than half that of Nebraska – the state with the second lowest submission rate. Florida’s contribution to national salmonella outbreak surveillance accounts for less than a third of its population.

With a large population, disproportionately low participation in national outbreak surveillance and no isolate submission requirement, Florida’s salmonella surveillance mirrors Texas before the hot pepper outbreak. While Texas was able to improve its surveillance by asking for isolates, budget constraints limit Florida’s surveillance capacity, said Richard Hopkins, the state epidemiologist for the Florida Department of Health.

“If somehow, by some magic, Florida hospitals started sending the other 80 percent [of isolates] to the state public health lab, they wouldn’t have the capacity to do the [testing] that they do,” said Hopkins.

Funding issues are not limited to Florida, with health departments hurting across the country, said the CDC’s Williams. Without sufficient funding, departments have fewer resources to test isolates, conduct interviews and undertake investigations.

Foodborne outbreaks are more likely to go undetected in states lacking those surveillance and response mechanisms. While most of them will be small, localized clusters of illness, some with the scope of the hot pepper outbreak will also slip through the cracks, said Tennessee’s Jones.

“It’s just Russian roulette, waiting for enough bad things to line up,” he said, “And it’ll happen again.”

Comments are closed.