Salmonella Blog - Surveillance & analysis on salmonella news & outbreaks

An Arizona State University researcher is trying a radical approach to speed up the process of making influenza vaccines: using salmonella.

Currently, the 50-year-old process in use requires injecting a weakened flu virus into millions of fertilized hens' eggs, incubating them, and extracting and purifying the serum.

The whole process can take six months.

But if ASU researcher Roy Curtiss figures out how to make salmonella work, it could mean that people will drink a liquid with a salmonella bacterium that has been neutralized and laced with flu-virus genes.

Salmonella is a common cause of food poisoning, invading the gut and causing diarrhea and other symptoms. That same mechanism is what makes Curtiss confident that salmonella is a perfect delivery system for vaccines. His salmonella is genetically modified so it doesn't cause poisoning.

Salmonella is able to invade lymph nodes in the intestines, which then can trigger immunity in the rest of the body. That's a more direct route to spurring the immune system to make antibodies against an invader, such as a flu virus.

People could drink the vaccine. Curtiss said he thinks an oral vaccine would have wider acceptance than those given with needles because there is less pain and less risk of infection. Needles also are more expensive and require some medical expertise.

While there is no guarantee the process will become the vaccine method of choice for most Americans, including as a replacement for annual flu shots, it points to the multipronged research endeavors being funded to prepare for a flu pandemic that health officials long have feared.

Warm weather would seem an invitation to move meals outdoors, yet cooking out -- or grilling -- is not without risks, said Fadi Aramouni, Kansas State University Research and Extension food scientist.

Meat scientists and researchers at Kansas State University determined that ground beef browns at different rates, so that browning, long considered an indication that ground beef is cooked, is no longer an accurate indicator of doneness. "With meats and poultry, the only sure way to test safety and doneness is by using a meat thermometer," Aramouni said.

For ground beef, the recommended cooked temperature is 160 degrees. For beef, veal and lamb roasts, steaks and chops, medium is 160 degrees and well done, 170 degrees. For fresh pork, including ground pork, medium is 160 degrees and well done, 170 degrees. All poultry should reach a minimum of 165 degrees.

Starting with a frozen or partially frozen meat or poultry product typically increases the time needed for cooking, said Aramouni, who offered these summertime food safety tips:

• Use a grill according to the manufacturer's instructions.
• Allow plenty of time to prepare the grill and cook foods completely.
• Avoid cross contamination: use separate plates, platters, bowls, cutting boards and utensils for raw foods and cooked foods. In other words, don't carry cooked foods to the table on the same platter used for carrying the raw meats or poultry to the grill.
• Wait until grilled foods are ready -- or almost ready to eat -- before removing perishable salads and condiments from the refrigerator or cooler. If foods are allowed to sit out on a picnic table unnecessarily, the risk of contamination, either from the food itself or microorganisms (staph is an example) that may be in the environment, increases.
• Wash fresh fruits and vegetables, including leaf lettuce, which can host salmonella. Adding an unwashed lettuce leaf or tomato slice to a cooked hamburger may contaminate it.
• Keep food covered and out of direct sunlight.
• Watch holding time and clear the picnic table within 60 minutes or less; cover and chill leftovers or discard them, rather than risk foodborne illness.
• Clean the grill after each use.
• Wash hands frequently, especially before and after handling raw and cooked foods, before and after eating, playing catch or croquet, and petting the dog. If water is unavailable, a bottled hand sanitizer can substitute.

Dr. Larry Beuchat of Center for Food Safety at the University of Georgia led a presentation as part of a large symposium organized at a American Society for Microbiology meeting to examine the issue of foodborne diseases from non-potentially hazardous foods.

The sudden appearance of unpasteurized orange juice as a vehicle for Salmonella could be due to a variety of reasons including a greater amount of orange juice consumed and more importation of orange products from countries that might not have sanitary guidelines or regulations as strict as ours. It could also be due to better surveillance by public health officials and more sensitive detection methods.

"For many years individuals in the public health arena would not think of orange juice as a vehicle for Salmonella. When epidemiologists would collect information on Salmonella outbreaks, high acid beverages like orange juice were not considered to even possibly be involved as carriers," says Beuchat.

Beuchat notes that all outbreaks have been associated with unpasteurized orange juice. Anyone concerned should look for pasteurized orange juice. Most major grocery store brands are already pasteurized.

Orange juice and other foods traditionally not associated with foodborne disease outbreaks can still be a source of disease, although rare.

Foods that, because their acidity, moisture level, or a combination of both, are incapable of supporting the growth of foodborne pathogens or toxin production without storage time and temperature controls are defined by the U.S. Food Code as non-potentially hazardous foods. But this designation also includes foods that do not support growth but still may contain pathogenic organisms at sufficient levels to cause disease.

Since the mid-1990s a number outbreaks of salmonellosis have been associated with the consumption of unpasteurized orange juice. The sudden appearance of unpasteurized orange juice as a vehicle for Salmonella could be due to a variety of reasons including a greater amount of orange juice consumed and more importation of orange products from countries that might not have sanitary guidelines or regulations as strict as the US.

"The more we find out about the behavior of microorganisms in non-potentially hazardous foods the more we are beginning to understand that some of these foods are borderline or not consistent with the definition," says Dr. Larry Beuchat of Center for Food Safety at the University of Georgia.

State health officials say restaurant employees are better educated than they were a year ago, during South Carolina's largest salmonella outbreak in history.

Changes to inspections already were under way, reports The South Carolina State, when more than 300 people became sick and one man died after eating undercooked turkey at Camden's Old South buffet restaurant.

What makes inspections by the Department of Health and Environmental Control more effective today, officials say, is education about critical-risk factors and correction of violations on the spot, rather than giving restaurants 10 days to make corrections.

Last year, the Hospitality Association of South Carolina also introduced a program that allows restaurants to earn a "food safety seal of commitment." The seal signifies all managers working in a restaurant and at least 75 percent of its employees have been certified in food safety.

The first five restaurants -- all in the Upstate -- earned their seals last month.

Some samples of a Jamaican specialty tea sold in Georgia have tested positive for salmonella, a sometimes fatal infection, according to the state's agriculture commissioner.

Lab technicians at the Georgia Department of Agriculture confirmed Friday that packages of Caribbean Dreams Cerasee Tea tested positive for salmonella.

The tea was imported from Kingston, Jamaica. It was sold at Ocho Rios, a store in Tucker, and possibly other locations.

By Lonny Stark
May 17, 2006

E. coli O157:H7 -- Although it doesn't typically cause a fever, this bacteria inflicts more severe abdominal cramps as well as bloody diarrhea. In extreme cases, it may cause anemia, profuse bleeding, and kidney failure. E. coli is present in the feces of cattle, so contaminated beef is the most common cause of infection.

Salmonella -- Found in the intestines of birds, reptiles and mammals, this nasty bacteria causes all kinds of gastrointestinal distress in humans, including abdominal cramps and diarrhea. It can also cause a fever, and in those with weakened immune systems, it may invade the bloodstream and bones. Any improperly handled foods may be contaminated by Salmonella, but in recent years eggs have often been the cause of human infection.

Contamination often happens where the fruits and vegetables are grown. Run off water, nearby grazing animals and birds flying above all can contribute to the problem that happens more often than you might think.

A recent study shows that you're more likely to get sick from produce than poultry, beef and even eggs. So what can you do to cut your risk, asks WHDH-TV’s Byron Barnett.

The FDA says:

• Wash all fruits and vegetables, even if you only eat what's on the inside.
• Try using a soft brush on produce with hard surfaces and always wash your hands before handling any food.
• Also, avoid cross contamination by not keep any raw meat near produce when you're shopping.