TABLE 1441 Etiologic Agents for Foodborne Diseases and Usual Incubation Periods

A history of two or more people within a household becoming ill simultaneously may indicate a foodborne etiology. If additional cases occur within 24 to 36 h, nonfoodborne sources, such as viruses, are more likely. Patients should be questioned about inadequate food-handling practices at home, such as preparation of food several hours prior to consumption, insufficient cooking or reheating of food, cross contamination between raw and cooked foods on common preparation surfaces, or people with poor personal hygiene handling the food. 21

Patients should be questioned about other activities associated with an increased risk of foodborne disease, such as frequent restaurant meals, exposure to day-care centers, consumption of street-vended food or raw seafood, overseas travel, and camping with the ingestion of lake or steam water.

Host factors that reduce resistance and immunocompetence should be identified. The recent use of antibiotics and medications that reduce gastric acidity, such as H 2 blockers, proton-pump inhibitors, and antacids, should be identified. Identify patients with AIDS or other immunocompromised conditions.

The very young and the elderly have a higher incidence of infection and greater risk of complications from foodborne illnesses. Children younger than age 5 and adults older than age 65 have the highest attack rate for infection with E. coli and are at the greatest risk for hemolytic-uremic syndrome.14 Isolation rates for Salmonella reported to the CDC and the risk for bacteremia were highest among children under age 9 and adults over age 80. 14 Residents of chronic care facilities are at increased risk for illness and death because of their close proximity, increased frequency of fecal incontinence, and a general debilitated state with multiple concurrent illnesses.14

A recent history of swimming in pools, water parks, lakes, and other recreational water facilities is important and should raise suspicion for cryptosporidiosis, although other pathogens such as enterohemorrhagic E. coli have been linked to water-park outbreaks.2

Stool cultures should minimally include the most frequent causes of foodborne illnesses: Campylobacter, Salmonella, and Shigella.20 The frequency of E. coli O157:H7 foodborne illness has increased, and many laboratories routinely culture for it, as well. The Gram stain can identify Campylobacter, one of the most common causes of gastroenteritis, with a sensitivity of 66 to 99 percent and still has a role in the diagnosis of diarrheal disease. 20 Cultures for other organisms should be based on prevalence rates in the community or an increased index of suspicion based on history and physical examination. Emergency physicians should be cognizant of which pathogens are and, equally as important, are not routinely cultured for in their laboratories. Optimal sensitivity of the test requires more than a single specimen, preferably obtained in the emergency department, especially for ova and parasites. 20 Rectal swabs are not adequate for specimen collection.

Public health authorities usually become aware of and initiate investigations of potential foodborne or waterborne outbreaks when there is an increase in the frequency of pathogens reported to them by hospitals or a cluster of suspicious cases. Variations of this reporting structure do occur. Emergency physicians concerned about possible outbreaks should communicate with the infection control departments and microbiology laboratories in their hospitals.

Was this article helpful?

0 0
Spiritual Weight Loss Mentality

Spiritual Weight Loss Mentality

Awesome Ways To Get Over Your Mentality That Keeps you Overweight! This Book Is One Of The Most Valuable Resources In The World When It Comes To Results In Your Slim-down and Health Efforts! Day in day out we keep ourselves absorbed with those matters that matter the most to us. A lot of times, it might be just to survive and bring in some money. In doing so we at times disregard or forget about the extra matters that are essential to balance our lives. They’re even more essential to supply real meaning to our world. You have to pay attention to your wellness.

Get My Free Ebook


Post a comment