Major U.S. E.coli Outbreaks Decline, Salmonella Up
European scientists are scrambling to find the source of the E.coli outbreak in Germany that has infected more than 2,400 people and killed 23 of them.
The German outbreak is caused by the rare strain of Shiga toxin-producing E.coli known as STEC O104:H4. It appears to be the deadliest outbreak of E.coli ever seen, with a third of patients developing the severe complication called hemolytic uremic syndrome (HUS), which frequently leads to kidney failure and can result in death.
Public health officials in the United States focus on the deadly Shiga toxin-producing E.coli infection known as O157:H7, which is best known for causing the 1993 outbreak that killed four people who ate tainted hamburgers from Jack in the Box.
The incidence of that infection fell by roughly half between 1997 and 2010, according to Vital Signs, an annual food safety report that summarizes data from the Centers for Disease Control and Prevention’s Foodborne Diseases Active Surveillance Network (FoodNet).
The report attributed the drop to improved slaughter methods, testing, better inspections and other efforts. Meat is often cooked, offering another layer of protection.
CDC estimates that one in six people in the United States gets sick from eating contaminated food each year. Foodborne illness is blamed for about 3,000 deaths annually.
While incidence of U.S. O157:H7 infections fell in 2010, there was a nearly 58 percent rise in other Shiga-toxin producing E.coli infections, which scientists refer to as STEC non-O157. Officials began monitoring those infections in 2000.
The bacteria responsible for Germany’s outbreak falls into that category. So far, the only reported cases in the United States are people who traveled to areas affected by the German outbreak.
The rise in other Shiga-toxin producing E.coli infections appears to be mostly due to an increase in testing and reporting, said Christopher Braden, director of the CDC’s division of foodborne, waterborne and environmental diseases.
“We’re making progress and that’s good. On the other hand, we’re really not at a point where we have the necessary regulatory and diagnostic infrastructure to deal with the type of outbreak that we’re seeing in Europe,” said J. Glenn Morris, director of the Emerging Pathogens Institute at the University of Florida.
CDC Director Thomas Frieden told reporters he was concerned about budget cuts at “state and local public health departments, which may undermine our ability to both detect and respond to outbreaks.”
“Pathogens are good at changing and emerging in unexpected ways … We don’t expect the outbreak in Germany to jump from Germany to the U.S. However, a similar strain or type of outbreak could occur,” Braden said.
Salmonella infection is the most common U.S. foodborne illness, and the United States has made no progress reducing outbreaks over the last 15 years.
Salmonella infections in 2010 were virtually unchanged from 1996 to 1998, when surveillance began, but were up 10 percent from the period from 2006 to 2008, the report said.
Last year, a U.S. salmonella outbreak resulted in the recall of nearly half a billion eggs. Salmonella is also linked to contaminated meats, produce and processed foods. In 2010, it caused nearly 2,300 hospitalizations and 29 deaths.
While the Vital Signs report was mixed, Morris said the reduction in O157:H7 infections showed that “if industry really pays attention, and there is a regulatory structure to focus attention on it, we can do something about it.”
(Editing by Mohammad Zargham)