The CDC Reports That Salmonella Is Still A Major Problem

Salmonella food infections continue despite success reducing disease caused by other pathogens, the Centers for Disease Control and Prevention reports.

Salmonella should be targeted because while infection rates have not declined significantly in more than a decade, they are one of the most common, the CDC reports in its latest Vital Signs.

Contaminated food causes approximately 1,000 reported disease outbreaks and an estimated 48 million illnesses, 128,000 hospitalizations, and 3,000 deaths annually in the U.S. Salmonella causes 1 million foodborne infections annually, incurring an estimated $365 million in direct medical costs. Salmonella infections in 2010 increased 10% from 2006-2008.

The same prevention measures that reduced Escherichia coli infections to less than 1 case per 100,000 need to be applied more broadly to reduce Salmonella and other infections, the CDC reports. These measures include:

–cleaner slaughter methods, microbial testing, and better inspections in ground beef processing plants;

–cooking meat thoroughly, and increased awareness in restaurants and homes of the risk of undercooked ground beef;

–vigorously detecting and investigating outbreaks; and

–recalling contaminated food. 234 beef recalls have occurred since the Shiga toxin-producing Escherichia coli (STEC) O157 was declared an adulterant in ground beef in 1994

New national health objectives target a 25% reduction in Salmonella infections by 2020 and 25%-50% reductions for five other infections and hemolytic uremic syndrome. These targets could prevent an estimated 4.6 million illnesses, 68,000 hospitalizations, and 1,470 deaths, and save $421 million in direct medical costs associated with Salmonella infection alone.

But, the U.S. still faces threats from E. coli, Dennis G. Maki, MD, a Master of the American College of Physicians, tells NPR that it’s likely the U.S. will see an E. coli outbreak involving travelers returning from Europe. The European outbreak is hospitalizing about a third of its victims, which he called extraordinary.

Food safety practices are described at the CDC, the Food Safety Working Group, at FoodSafety.gov, and at the Partnership for Food Safety Education.

Detailed findings from Vital Signs

The Foodborne Diseases Active Surveillance Network (FoodNet) follows about 15% of the U.S. population for laboratory-confirmed infections with nine common foodborne pathogens. Overall and pathogen-specific changes in incidence were estimated from 1996-1998 to 2010 and from 2006-2008 to 2010.

A total of 19,089 infections, 4,247 hospitalizations, and 68 deaths were reported from FoodNet sites in 2010. Salmonella was the most common infection reported (17.6 illnesses per 100,000 persons) and was associated with the largest number of hospitalizations (2,290) and deaths (29). No significant change Salmonella infections has occurred since the start of surveillance during the period of 1996-1998.

(STEC) O157 infection caused 0.9 illnesses per 100,000 people. Compared with 1996-1998, overall incidence of infection with six key pathogens in 2010 was 23% lower, and pathogen-specific incidence was lower for Campylobacter, Listeria, STEC O157, Shigella, and Yersinia infection, but higher for Vibrio infection. Compared with a more recent period, 2006-2008, incidence in 2010 was lower for STEC O157 and Shigella infection but higher for Vibrio infection.

Among the 7,564 (92%) Salmonella isolates serotyped, the most common were Enteritidis (22%), Newport (14%), and Typhimurium (13%).

For the other pathogens, the number of infections and incidence were: Campylobacter (6,365; 13.6 per 100,000), Shigella (1,780; 3.8 per 100,000), Cryptosporidium (1,290; 2.8 per 100,000), STEC non-O157 (451; 1.0 per 100,000); STEC O157 (442; 0.9 per 100,000), Vibrio (193; 0.4 per 100,000), Yersinia (159; 0.3 per 100,000), Listeria (125; 0.3 per 100,000), and Cyclospora (28; 0.1 per 100,000).

The percentage of patients hospitalized ranged from 0% for Cyclospora to 90% for Listeria infection. Fatalities ranged from 0% for Cyclospora and Shigella to 13% for Listeria infection. Overall, the percentage of patients hospitalized (40%) and killed (1.5%) were highest among those 60 years or older.

The overall incidence for the six key pathogens (Campylobacter, Listeria, Salmonella, STEC O157, Yersinia, and Vibrio) was 23% lower in 2010 than during 1996-1998.

Incidence was significantly lower for Shigella (57% decrease), Yersinia (52%), STEC O157 (44%), Listeria (38% , and Campylobacter (27%) but higher for Vibrio (115% increase). It did not change significantly for Cryptosporidium.

Compared with 2006-2008, overall incidence was not significantly different in 2010. The incidence was significantly lower for STEC O157 (29% decrease) and Shigella (29% decrease) and significantly higher for Vibrio (39% increase). The incidence did not change significantly for Campylobacter, Cryptosporidium, Listeria, and Yersinia.