Increases in foodborne illnesses from salmonella and escherichia coli during 2006 could be due to outbreaks in previously unaffected food such as peanut butter and spinach, according to the findings of a new report.
The Centers for Disease Control and Prevention (CDC) findings, which reverse the progress made in 2003 and 2004, will concern food processors already forced to implement stringent food safety procedures.
Food-related illnesses can prove costly for food manufacturers in terms of recalls and loss of brand trust. Nationwide outbreaks however can be disastrous, especially when fatalities occur.
The increase, which takes the illness rates back to the levels experienced during data collections from 1996 to 1998 - the main comparative period of the report - is not fully understood by the scientists.
Dr. Julie Gerberding, CDC director said recent outbreaks demonstrated that too many people were falling sick from foodborne illnesses.
"For instance, the outbreaks involving tomatoes, lettuce and spinach underscore the need to more effectively prevent contamination of produce," she said.
Gerberding also said during a press confrerence on the findings that while the hamburger, for instance was "safer than it has ever been", more needed to be done to prevent pathogen cross-contamination that can lead to large outbreaks.
The findings are from 2006 data reported to the CDC as part of the agency's Foodborne Diseases Active Surveillance Network (also known as FoodNet). FoodNet collects data from 10 US states regarding diseases caused by enteric pathogens transmitted commonly through food.
FoodNet quantifies and monitors the incidence of these infections by conducting active, population-based surveillance for laboratory-confirmed illnesses, following a victim's visit to a hospital of clinic.
Data collected from the 10 states, which have a combined population of 45 million and make up around 15 per cent of the nation, gives a snapshot of the level food related illness across the US.
The CDC identified 17,252 laboratory-confirmed cases of food poisoning in 2006, including 6,655 cases of Salmonella and 590 cases of E.coli O157.
The report also found that vibrio infections, which often relate to the consumption of raw shellfish like oysters, have increased 78 per cent to 154 cases in 2006 - the highest level since FoodNet began conducting surveillance in 1996.
However, Camplylobacter, Listeria, Shigella and Yersinia show a sustained decline in incidence compared to 1996-1998, although the CDC said that most of the present decrease was due to falls experienced between 1999 and 2002.
Gerberding said that the CDC would further co-operate with its FoodNet partners, including the United States Department of Agriculture (USDA), the Food and Drug Administration (FDA) and state surveillance sites, to improve service levels.
"We're also working to strengthen our ability to quickly detect and identify foodborne illnesses. We know the faster we can detect an outbreak, the faster we can take actions that will help protect people."
The possible causes of the rise to previous figures, suggested by the CDC follow a serious of foodborne outbreaks in the US recently.
This year ConAgra was forced to recall Peter Pan and Great Value branded peanut butter products linked to a contaminated plant in Georgia.
The products are linked to a salmonella outbreak that sickened at least 425 people in 44 states.
Meanwhile an outbreak of E. coli in September last year was traced back to packaged cut spinach originating from California. The outbreak killed three people and sickened more than 200 people across the US.
The outbreak has since been traced back to a 50-acre spinach plot. The contaminated strain has been found in a nearby stream and in cattle feces and in wild pigs, officials said.
During November to December last year lettuce contaminated with E. coli was blamed for infecting at least 48 Taco Bell customers in five states.