Food Safety Issues for Older Adults

1. Food SafetyIssues for Older Adults

6. Foodborne Illnesses More than 200 known diseases are transmitted through food. Causes include: Bacteria Viruses Parasites Toxins Prions

7. Foodborne Illness in U.S. 76 million cases/yr* 62 M from unknown pathogens 325,000 hospitalizations* 5,000 deaths* Not all persons at equal risk of contracting a foodborne illness *Estimates; reported cases are much lower Mead et al., 1999

8. Sensitive Populations in the U.S Population Individuals % pop. Pregnancies 6.0 mil 2.1% Neonates 4.0 mil 1.4% Elderly (>65) 35 mil 12.5% Nursing Care Residents 1.6 mil 0.6% Cancer patients (non-hosp.) 8.9 mil 3.2% Organ transplant patients 110,270 0.04% AIDS patients 223,000 0.08% Total 55.8 mil 19.9% Sources: US Census Bureau, 2001, CDC, 1996, 1997, 2001

9. Factors Affecting Risk of Foodborne Illness Aging Population As of 2000: 35 million in U.S. ?65 years (12.5% of pop.) 4 million in U.S. ?85 years (2% pop.) 5% of ?65 & 20% ?85 year-olds in nursing homes By 2030: 70 million in U.S. ?65 years (20% pop.) By 2050: 20% world population ?65 years Sources: Sources:

12. Immune System and Aging: Background Innate (or Natural) Immunity: Most primitive of two immune systems. First response to the presence of an antigen (substance that can induce a detectable immune response when introduced to an animal). Once encountered, the response is immediate, but nonspecific. Response is short lived and may not be able to protect against an overwhelming or prolonged attack by antigens. Found in skin, mucosal secretions, intestinal pH, Peyer�s Patch in intestine, natural killer cells, reticuloendothelial system NK = natural killer cells, NK also described as part of the cellular immune system by many, involved with the initial response to infection with viruses and other intracellular Acquired (Adaptive) Immunity: Specific response to antigen; initial response slow, but has memory and long-term response. Adaptive immunity composed of 2 immune systems: humoral and cell-mediated immunity. Both components are capable of developing memory In humoral immune response, pathogens encounter B-lymphocytes (or B cells) and eventually create plasma and memory cells which destroy the pathogen. In a cellular or cell-mediated immune response, pathogens encounter T-lymphocytes or T-cells, and eventually create cytotoxic, helper and memory cells which destroy the pathogen.Innate (or Natural) Immunity: Most primitive of two immune systems. First response to the presence of an antigen (substance that can induce a detectable immune response when introduced to an animal). Once encountered, the response is immediate, but nonspecific. Response is short lived and may not be able to protect against an overwhelming or prolonged attack by antigens. Found in skin, mucosal secretions, intestinal pH, Peyer�s Patch in intestine, natural killer cells, reticuloendothelial system NK = natural killer cells, NK also described as part of the cellular immune system by many, involved with the initial response to infection with viruses and other intracellular Acquired (Adaptive) Immunity: Specific response to antigen; initial response slow, but has memory and long-term response. Adaptive immunity composed of 2 immune systems: humoral and cell-mediated immunity. Both components are capable of developing memory In humoral immune response, pathogens encounter B-lymphocytes (or B cells) and eventually create plasma and memory cells which destroy the pathogen. In a cellular or cell-mediated immune response, pathogens encounter T-lymphocytes or T-cells, and eventually create cytotoxic, helper and memory cells which destroy the pathogen.

13. Changes in Immune Function with Aging Ability of immune system declines with age Gradual decline in T-cell function Fewer na�ve and more memory T-cells, which reduces ability to mount immune response when new exposures to pathogens occur Gradual decline in B-cell function Decreased response by na�ve B cells to newly introduced antigens Aging B cells may produce abnormal antibodies Sources: Smith, 1997; Medeiros, 2004 Older adults lose adaptive immune function as a natural part of aging. There is an aging-associated shift in the T-cell population from na�ve to memory T-cells; thus, the capacity to respond to exposure to genetically-mutated or newly emerging pathogens is diminished in older adults. Cytokine production also declines with natural aging, affecting T-cell proliferation and differentiation processes under Interleukin-2 control. Without Interleukin-2, pathogens introduced into the aging body for the first time are less likely to produce an immune response. Humoral immunity also is affected by aging as B-cell activation is co-dependent on na�ve T-cell activation. Susceptibility to foodborne infections can thus increase in the elderly when exposed to newly emerging or genetically-mutated pathogens. Older adults lose adaptive immune function as a natural part of aging. There is an aging-associated shift in the T-cell population from na�ve to memory T-cells; thus, the capacity to respond to exposure to genetically-mutated or newly emerging pathogens is diminished in older adults. Cytokine production also declines with natural aging, affecting T-cell proliferation and differentiation processes under Interleukin-2 control. Without Interleukin-2, pathogens introduced into the aging body for the first time are less likely to produce an immune response. Humoral immunity also is affected by aging as B-cell activation is co-dependent on na�ve T-cell activation. Susceptibility to foodborne infections can thus increase in the elderly when exposed to newly emerging or genetically-mutated pathogens.

14. GI Tract and Aging Atrophy & inflammation of gastric mucosa increases with aging Seen in ~ 50% of those over age 50 Decreased GI motility with aging Digestion rate slows, enables growth of pathogens Use of antacids May block gastric output and reduce ability to resist infection Intestinal motility and mucosal immune function decrease with normal aging, increasing susceptibility to systemic infection via the gut . Fecal impaction from loss of smooth muscle contractility is also common with aging, but it is not clear if prolonged exposure of pathogens to intestinal epithelium is a risk factor for pathogen infection. Overuse of H2-receptor antagonists or over-the-counter antacids, which is common among older adults, may cause hypochlohydria and further reduce the ability to resist infection. Intestinal motility and mucosal immune function decrease with normal aging, increasing susceptibility to systemic infection via the gut . Fecal impaction from loss of smooth muscle contractility is also common with aging, but it is not clear if prolonged exposure of pathogens to intestinal epithelium is a risk factor for pathogen infection. Overuse of H2-receptor antagonists or over-the-counter antacids, which is common among older adults, may cause hypochlohydria and further reduce the ability to resist infection.

15. Food Safety Risk Factors Associated with Chronic Diseases Diabetes Affects 18-20% of persons over age 65 Higher risk of FBI if in poor control Cancer Chemotherapy may suppress immune system Immuno-suppressive drugs used with solid organ transplant patients Prolonged use of antibiotics The ill elderly are at increased vulnerability to opportunistic infection because of immune suppression associated both with aging and the disease, as well as therapeutic regimens like chemotherapy that may be used to treat the disease. Diabetes mellitus, which affects 18-20% of persons over age 65 in the U.S. can promote systemic pathogenic infection through persistent hyperglycemia and loss of microcirculation efficiency. Leading causes of death in individuals 65 years and older are often related to compromise of the immune system. For example, 70% of deaths occurring from cancer are among elderly patients. Prolonged use of antibiotics may stimulate overgrowth of colonic pathogens and the loss of competitive inhibition provided by the natural microflora. The ill elderly are at increased vulnerability to opportunistic infection because of immune suppression associated both with aging and the disease, as well as therapeutic regimens like chemotherapy that may be used to treat the disease. Diabetes mellitus, which affects 18-20% of persons over age 65 in the U.S. can promote systemic pathogenic infection through persistent hyperglycemia and loss of microcirculation efficiency. Leading causes of death in individuals 65 years and older are often related to compromise of the immune system. For example, 70% of deaths occurring from cancer are among elderly patients. Prolonged use of antibiotics may stimulate overgrowth of colonic pathogens and the loss of competitive inhibition provided by the natural microflora.

16. Other Food Safety Risk FactorsAssociated with Aging Sense of taste and smell declines Greater likelihood of dementia and malnutrition NAIDS (Nutritionally Acquired Immunodeficiency Syndrome) Lack of exercise Can adversely affect immune function Entry into nursing homes In older individuals, there is a greater likelihood of malnutrition, which also increases susceptibility for infection. A deficiency of protein, zinc, selenium, iron, copper, vitamins A, C, E, B-6 or folic acid can lead to impaired immune function. The influence of dementia on malnutrition and susceptibility to infection is unclear. One study with Alzheimer�s patients found further cognitive decline after infection due to elevations in Interkeukin-1�. Malnutrition affects taste acuity in the elderly and may account for the behavioral tendency to consume contaminated food items. While not directly causal, these studies reinforce the need to protect cognitively-impaired adults from foodborne infections. Loss of mobility in the aged can impair immune function. Elderly male runners have increased production of Interleukin-2, Interleukin-4 and Interferon-? compared to sedentary elderly controls. In a review of accumulated data, Kohut and Senchina (2004) concluded that long-term exercise interventions may be useful in improving immune function in the elderly.In older individuals, there is a greater likelihood of malnutrition, which also increases susceptibility for infection. A deficiency of protein, zinc, selenium, iron, copper, vitamins A, C, E, B-6 or folic acid can lead to impaired immune function. The influence of dementia on malnutrition and susceptibility to infection is unclear. One study with Alzheimer�s patients found further cognitive decline after infection due to elevations in Interkeukin-1�. Malnutrition affects taste acuity in the elderly and may account for the behavioral tendency to consume contaminated food items. While not directly causal, these studies reinforce the need to protect cognitively-impaired adults from foodborne infections. Loss of mobility in the aged can impair immune function. Elderly male runners have increased production of Interleukin-2, Interleukin-4 and Interferon-? compared to sedentary elderly controls. In a review of accumulated data, Kohut and Senchina (2004) concluded that long-term exercise interventions may be useful in improving immune function in the elderly.

17. Food Preference Factors that Affecting Risk of Foodborne Illness In General: Eat out more often Purchase more convenience and take-out foods that require minimal cooking Prefer our foods rare or raw Less food safety education in home and school Among elderly 50% reported eating undercooked eggs Men and those living alone more like to practice unsafe food handling behaviors than women and couples Older adults have established food preparation and handling practices, some of which may increase the likelihood of a foodborne infection. Multi-state surveys have found persons over age 60 more careful than younger adults for some, but not all, food handling and consumption behaviors. For example, Yang et al. [1998] found persons over age 60 less likely to eat pink hamburgers or raw oysters and more likely to wash their hands and food preparation surfaces than younger persons. Still, ~13% of older adults reported eating pink hamburgers and not usually washing their hands or cutting boards after contact with raw meat or chicken and 50% said they ate undercooked eggs [Yang et al. 1998]. Among older adults, men and individuals living alone were more likely to practice unsafe food handling behaviors than women and persons living with a significant other [Hanson and Benedict, 2002]. Li-Cohen and Bruhn [2002] found consumers =65 years more likely than younger consumers to rinse cutting boards and sinks before and after washing fresh produce, but less likely to keep raw animal products separated from fresh produce in the refrigerator and to wash whole melons before cutting. Others have reported not using a meat thermometer to determine doneness, not refrigerating foods promptly, putting large quantities of hot food in the refrigerator without portioning into smaller amounts, and thawing frozen food on the counter as common themes among older adults who regularly prepare meals at home. In addition, Johnson et al. [1998] found that 70% of elderly consumers studied had refrigerators that were too warm for safe storage of food (=6�C). Older adults have established food preparation and handling practices, some of which may increase the likelihood of a foodborne infection. Multi-state surveys have found persons over age 60 more careful than younger adults for some, but not all, food handling and consumption behaviors. For example, Yang et al. [1998] found persons over age 60 less likely to eat pink hamburgers or raw oysters and more likely to wash their hands and food preparation surfaces than younger persons. Still, ~13% of older adults reported eating pink hamburgers and not usually washing their hands or cutting boards after contact with raw meat or chicken and 50% said they ate undercooked eggs [Yang et al. 1998]. Among older adults, men and individuals living alone were more likely to practice unsafe food handling behaviors than women and persons living with a significant other [Hanson and Benedict, 2002]. Li-Cohen and Bruhn [2002] found consumers =65 years more likely than younger consumers to rinse cutting boards and sinks before and after washing fresh produce, but less likely to keep raw animal products separated from fresh produce in the refrigerator and to wash whole melons before cutting. Others have reported not using a meat thermometer to determine doneness, not refrigerating foods promptly, putting large quantities of hot food in the refrigerator without portioning into smaller amounts, and thawing frozen food on the counter as common themes among older adults who regularly prepare meals at home. In addition, Johnson et al. [1998] found that 70% of elderly consumers studied had refrigerators that were too warm for safe storage of food (=6�C).

18. Environmental Factors Affecting Risk of Foodborne Illness Complexities of the Food System Industry consolidation and mass distribution Wide geographic distribution of foods Multiple uses of transport vehicles Changes in Travel and Commerce Increased international travel Increased diversity of foods in market place

19. Environmental Factors Affecting Risk of Foodborne Illness Economic Development and Land Use Food animals generate 1.6 billion tons of manure/yr Shift from cold season oyster harvest in Gulf of Mexico to year round harvest has resulted in increase in V. vulnificus Breakdown of Public Health Infrastructure Less than 2% of cases reported to health dept.

20. Pathogen-based Factors Affecting Risk of Foodborne Illness Changing micro-organisms More virulent strains E. coli O157:H7, Salmonella Enteritidis Development of antimicrobial resistance Salmonella Typhimurium DT140 Resistant to ampicillin, streptomycin, tetracycline Camplyobacter jejuni Resistant to fluroquinolones

21. Pathogen Issues in Foods are Changing Newly recognized pathogens Pathogens have spread worldwide with transport of food Many pathogens have reservoirs in healthy food animals Associated with new food vehicles Tauxe EID 1997

22. Pathogens in Foods Today Food usually looks, smells and tastes normal Traditional food preparation methods may not kill some �emerging� pathogens Undercooked eggs Rare ground beef

23. Typical Symptoms of Foodborne Infection Gastrointestinal upset Vomiting Diarrhea Pain and cramps Fever, chills Headache, muscle pain

24. Chronic Sequelae Chronic = persisting for a long time Sequelae = secondary to initial infection May be permanent and very severe May occur in 2 to 3% of foodborne disease cases Lindsay EID, 1997

25. Examples of Chronic Sequelae Arthritis Autoimmune thyroid disease Inflammatory bowel disease Kidney failure Neuromuscular disorders Congenital impairments Encephalitis (inflammation of the brain) Meningitis (inflammation of the membranes covering the brain & spinal cord)

26. The ElderlyPathogens of Special Importance E. coli O157:H7 Salmonella species Listeria monocytogenes Vibrio species Yersinia Campylobacter jejuni Clostridium perfringens Staphylococcus aureus

27. E. Coli O157:H7 and Older Adults E. coli O157:H7 About 12% of cases occur in persons over 60 years Mortality rate of 12-35% in nursing home outbreaks Elderly at risk for two complications of E. coli infection: Hemolytic uremic syndrome (HUS) Thrombotic thrombocytopenic purpura (TTP)

28. Salmonella and Older Adults Salmonella outbreaks have been associated with: Raw eggs Undercooked poultry and meat Raw milk Produce and unpasteurized juice Salmonella Enteritidis can be present both inside the egg and on the outside of shells Consumption of undercooked eggs most common risky food behavior among persons > 60 years

29. Salmonella and Older Adults Onset time can take up to 48 hours Salmonella symptoms are severe in the elderly Seniors may exhibit classic symptoms such as gastroenteritis, nausea, cramps, diarrhea Seniors more likely to have invasive salmonellosis with bacteremia, septicemia Septicemia associated with subsequent infection of organs Source: FDA Bad Bug Book Septicemia - invasion and persistence of pathogenic bacteria in the blood stream (bacteremia) associated with subsequent infection of organsSepticemia - invasion and persistence of pathogenic bacteria in the blood stream (bacteremia) associated with subsequent infection of organs

30. Salmonella and Older Adults Salmonella outbreaks in nursing homes have high potential for morbidity/mortality Groups of susceptible elderly individuals sharing meals Visitors and staff may carry pathogens from outside the homes Eggs are a major cause of Salmonella Enteritidis outbreaks Most nursing homes and hospitals serve only pasteurized eggs

31. Other Pathogens of Special Importance among Older Adults Listeria monocytogenes Immune compromised elderly at highest risk Hospitalization rate if >age 60 = 96% Vibrio species Highest rate in 65-74 year olds Sources: Levine et al., 1991; Altekruse et al., 1999; FoodNet, 2001; Ailes et al., 2004

32. Other Pathogens of Special Importance among Older Adults Campylobacter jejuni Elderly not more susceptible to illness, but more at risk for complications & subsequent death Clostridium perfringens & Staph. aureus More common among nursing home residents than in general population

33. Food Safety Recommendationsfor Seniors Practice proper hygiene Wash hands thoroughly with warm, soapy water before food preparation and consumption Cook foods thoroughly Cook meats, poultry, and fish thoroughly Cook eggs until both the yolk and white are firm Use a thermometer to make sure egg dishes are cooked to 160 degrees F Reheat lunch meats and hot dogs to steaming hot or 165 degrees F

34. Food Safety Recommendationsfor Seniors Avoid cross-contamination Wash knives and food preparation surfaces with warm, soapy water after contact with raw poultry, meat, seafood Rinse fresh produce thoroughly before consuming Keep foods at safe temperatures Refrigerator temperature should be 35 to 40 F Freezer temperature should be 0 F or lower Keep hot foods hot Refrigerate perishable food within 2 hours or less

35. Food Safety Recommendationsfor Seniors Avoid the following foods: Raw fish, seafood, poultry Raw milk and raw milk cheeses Raw sprouts Unpasteurized juices, cheese, yogurt, milk Cold smoked fish Source: www.fsis.usda.gov

36. Recap� Immunity and gastrointestinal function change with aging Older adults at greater risk of complications from certain foodborne illnesses Pathogens of particular importance include: Listeria monocytogenes E. coli O157:H7 Salmonella spp. Vibrio