Know Thine Enemy - January 2007

You can’t prevent a food safety outbreak without
knowing exactly what you’re up against.

By David Eddy
Senior Western Editor

Editor’s Note: This article is the first in a six-part series on food safety, an issue that has come to the forefront of grower concerns in the last few months. This story looks at potential contaminants growers should recognize. Subsequent articles will examine consequences of inaction; prevention; postharvest pointers; what to do if an outbreak occurs; and potential future regulations.

It's a sobering thought, but more than 250 different foodborne illnesses have been described. Fortunately, only four are considered common by the Centers for Disease Control and Prevention: those caused by the bacteria E. coli O157:H7, Salmonella, and Campylobacter, and by a group of viruses called Noroviruses, previously known as Norwalk viruses. Campylobacter live in birds and cause problems when poultry is under-cooked, and Noroviruses are only believed to be spread person to person. Fruit growers really only need to be concerned by the remaining two in the course of their business, but they are a deadly duo indeed.

Like Campylobacter, Salmonella is also a bacterium that is widespread in the intestines of birds, as well as reptiles and mammals. It can be spread to humans via a variety of different foods. In the past, Salmonella was only thought to be a concern in foods of animal origin, particularly chicken and eggs. However, because the microscopic living creatures can spread via animal feces, fruit and vegetable growers

- particularly those who use manure

- need to be very cautious.

Growers need look no further than two recent incidents involving Salmonella. The most recent involved the recall of 62,000 cartons of Mexican cantaloupes that were shipped during the first week of November. There have been no reports of illness, but food safety experts are particularly concerned about cantaloupes, because a cantaloupe's netting provides excellent hiding places for the bacteria. The other widespread Salmonella case involved approximately 180 people in 19 states sickened by Salmonella on tomatoes. This case was also particularly troubling because it's been found that if the bacteria contaminates the plant while flowering, Salmonella literally grows inside the fruit.

Enemy No. 1
Every grower is familiar with the E. coli outbreak in Salinas, CA, spinach this past fall that killed three people and sickened 200. But what you may not know is that if 200 people reported sickness, experts peg the actual number sickened at 40,000 because the vast majority of people simply ride it out. Most strains of E. coli are harmless, but not the one involved with the spinach outbreak, E. coli O157:H7, which kills about 60 Americans each year. The strain can live in the intestines of healthy cattle, deer, goats, and sheep, and can be found in most places these animals are found, including petting zoos.

Growers need to keep in mind that while consumers can wash some E. coli off their fruits and vegetables, there's no way to know if they got it all. The organisms are microscopic, and it doesn't take many to sicken or even kill someone, particularly the very old and the very young. Because cattle manure is considered by far the greatest threat to fruits and vegetables, it's critical for growers who use compost to be very careful, and for systematic monitoring of any water used for irrigation or washing. Remember, it's one for all.

E-mail questions or comments about this article to deddy@meistermedia.com