Of Pathogens and Produce: Let the salad-lover beware
Until recently, foodborne illnesses have usually been associated with contaminated meat and poultry. Improved surveillance of and practices by those industries, as well as public education about proper handling have helped lower the rates of those sources. But an increase in uncooked vegetables and contamination of these products has developed.
In the International Journal of Environmental Health Research article “Prevalence of multiple antibiotic-resistant Gram-negative bacteria on bagged, ready-to-eat baby spinach,” by S. Walia, et al (Vol. 23, No.2, for April, 2013, pages 108-118), infections caused by pathogens (microorganisms that cause disease) found on uncooked fresh produce are increasing. Perhaps even more concerning is that many of these germs carry the genes for multiple-drug resistance. Thus, if someone consumes these pathogens on their produce, they could get an infection and/or have these dangerous genes passed on to bacteria in their intestines. Antibiotics used in agriculture to increase yield are suspected to have caused the antibiotic-resistant organisms to survive and even thrive. There has been an increase in serious intestinal infections in the most vulnerable – children, the elderly, and those with a weakened immune system.
The study reported in this article noted that pathogens are found even in bagged, ready-to-eat baby spinach. Other studies found pathogens on other produce. High-risk produce includes green onions, spinach and other leafy greens, cilantro, tomatoes, peppers, and alfalfa sprouts.
The CDC’s “Burden of Foodborne Illness: Findings” which were last updated 7/15/2016, states that 1 in 6 Americans develop a foodborne illness every year. Some half of infections are caused by pathogens not yet identified, and the other half are caused by 31 known microorganisms, but 8 account for the majority of cases of foodborne illness. Norovirus causes the most of these. Salmonella is also a common cause and the most likely to lead to hospitalization or death. (http://wwwnc.cdc.gov/eid/article/17/1/p1-1101 article).
In “Vital Signs: Incidence and Trends of Infection with Pathogens Transmitted Commonly Through Food – Foodborne Diseases Active Surveillance Network, 10 U.S. Sites 1996-2010″ (Morbidity and Mortality Weekly Report for 6/10/2011, Vol. 60, #22) it is noted that most foodborne illnesses occur in people that aren’t included in reported disease outbreaks. Most foodborne illnesses entail mild to severe diarrhea. In the vulnerable such as the elderly, and even in the healthy, severe complications like kidney damage and meningitis can develop.
In Eat, Drink and Be Wary by Charles M. Duncan (Lanham, MD: Rowman & Littlefield, 2015) it is stated that 20% of our fresh vegetables and 40% of our fruit and nuts are imported. This may be the greatest risk for foodborne infections, but this hasn’t been confirmed. Since fresh produce is the source of about half of foodborne illnesses a year, and since monitoring has decreased the past 5 years, a few precautions are worthwhile: wash meticulously all fruits and vegetables, even those with a rind you won’t eat, wash 15 seconds and rinse 15 seconds before and after preparing any produce.