week 13 lecture 2 Flashcards
annually in the US, how many foodborne illnesses occur
48 million
about 10 million are caused by
31 major pathogens
rest are caused by
poorly understood pathogens
how many hospitalizations?
128,000
how many deaths?
3000
what are the major culprits
salmonella enterica
campylobacter
listeria monocytogenes
toxoplasma gondii
salmonella causes ____ of illnesses
11%
salmonella causes ____ of hospitalizations
35%
salmonella causes ____ deaths
28%
campylobacter causes ___ illnesses
9%
campylobacter causes ____ of hospitalization
15%
listeria causes ____ of deaths
19%
toxoplasma gondii causes ____ of hospitalization
8%
toxoplasma gondii causes ____ of deaths
24%
most illnesses are caused by
leafy vegetables (22%)
dairy (14%)
furits-nuts (12%)
poultry (10%)
most deaths are caused by
poultry (19%) dairy (10%) vine-stalk vegetables (7%) fruits-nuts (6%) leafy vegetables (6%)
success against most foodborne pathogens has been
limitied
many key foodborne pathogens have ____ reservoirs
animal
these include
salmonella campylobacter shiga toxin-producing E. coli listeria toxoplasma
regulatory veterinarians include
USDA FSIS
FDA
CDC
State health departments
Food animal practicioners role
diagnosis, treatment, and prevention
all veterinary practitioners should be source of
info for public
many foodborne pathogens are also transmitted via
direct contact
salmonella _____ serovars, most of which have animal reservoirs
> 2,600
salmonella is a leading cause of
acute bacterial enteritis;
salmonella peack incidence in
summer
annual salmonella estimates in us
1.2 million illnesses
400 deaths
economic cost of 4.4 billion
salmonella incubation period
6-72 hours
self limiting acute enteritis lasting
3-7 days
invasive disease leading to
sepsis, plus or minus death
prevalence of multidrug resistance has increased over last 2 decades
increased treatment failures
increased risk and duration of hospitalization
increased mortality
reservoirs of salmonella
poultry cattle pigs horses dogs cats rodents reptiles amphibians fish wildlife humans
salmonell in cattle, horses and pigs disease ranges from
subclinical to acute onset of diarrhea, fever, anorexia, and dehydration
septicemia in neonates
meningitis
arthritis
uveitis
higher mortality
salmonella fecal shedding in reptiles approaches ___%
90
sale and distribution of small turtles has been prohibited since
1975; acquisition of small turtles still exists
salmonella prevalence among houses of laying hens ___% and broilers ____%
86%
88%
clinical signs in chickens
usually are subclinical
prevalence of salmonella shedding in healthy dogs
1-36%
prevalence of salmonella shedding in cats
1-18%
Transmission of salmonella
fecal-oral
foodborn exposure most common (90%)
fecal contamination of foods derived from infected animals (raw/undercooked eeggs, beef, porg, unpasteurized dairy products)
contamination of crops
transmission via direct contact of infected animals affects
occupational
people with pets
open farms, petting zoos, county/state fairs;
outbreaks of salmonella commonly associated with
retpile exhibits, livestock contact, and chicks at easter time
campylobacter jejuni is most common cause of
campylobacter diarrhea in peopel; also C. coli
campylobacter occurs
worldwide
campylobacter annual estimates
1.1 million illnesses
75 deaths
economic cost of 1.7 billion
campylobacter incubation period
2-5 days
generally a self-limiting enteritis but can produce
invasive disease (7-14 days)
campylobacter may mimic
acute appendicitis
potential complications of campylobacter
guillain-barre syndrome
reactive arthritis
guillain-barre syndrome
acute immune-mediated disorder of PNS (0.1% OF CASES)
reactive arthritis
1% of cases
reservoirs of campylobacter
poultry and cattle (most important) puppies and kittens pigs sheep rodents
campylobacter in poultry
subclinical
prevalence of fecal shedding amoung broiler chickens
60-90%
____% of the packages of raw chicken sold in U.S. and canadian grocery stores are postiive
60-70%
campylobacter in cattle
subclinical reservoir
prevalence among dairy cattle ranges from _____
30-50%
prevalence among feedlot cattle may reach ___%
90%
____ in calves
enteritis
transmission
primarily fecal oral transmission
foodborne
waterborne
direct contact
foodborne
undercooked poultry
shiga-toxin producing e. coli (stec)
STEC produce cytotoxins
STEC have been identified in most areas of th
the world
annual estimates in us of STEC
176,000 Illnesses
20 deaths
economic cost of 280 million
public health implications
acute diarrhea, may become hemorrhagic
incubation period
2-10 days
generally lasts for
5-10 days
most severe clinical manifestation is
hemolytic uremic syndrome
acute renal failure
hemolytic anemia
thrombocytopenia
____% of children with E. coli O157:H7 infection develop HUS
15
____ require dialysis
50%
___ die
5%
reservoirs of STEC
CATTLE
HUMANS
OTHER RUMINATNS
WILDLIFE?
STEC cause clinical disease in cattle?
no
higher prevalence of STEC in ____ cattle than in ____ cattl
feedlot (10%) dairy cattle (5%)
higher prevelance of stec in
summer
shedding in cattle typically occurs for
days-months; may be intermittent
some may shed for
> 1 year
super shedders
> 10,000 CFU/g of feces
transmission
low infectious dose (<10 organisms) primarily fecal-oral transmission foodborne waterborne direct contact
foodborne STEC
undercooked beef
produce
unpasteurized milk
waterborne
drinking water
recreational use water
direct contact
dariy farms
county/state fairs
petting zoos
listeria
extremely hardy;
can form biofilm in food production facilities
can multiply in contaminated foods at refrigeration temperatures
listeria occurs
worldwide
listeria lower ____ higher ____
morbidity; mortality
annual estimates of listeria in us
1,600 illnesses
255 deaths
economic cost of 2.6 billion
public health implications of listeria
often asymptomatic or a cause of mild febrile illness in healthy adults
severe disease among
elderly or immunocompromised individuals
case fatality ranges from ____ among infected animals
15-30%
listeria has dangerous implications for pregnant women
abortion
stillbirth
live infant with septicemia, meningitis, and encephalitis
infected children may be
affected at birth or later in neonatal period
case fatality among infected newborns ranges from
20-30%
mother may have
vague or no overt illness
reservoirs of listeria
soil water vegetable atter silage mammals birds fish
listeria can survive in
soil for years; can proliferate over a wide pH range (5-9)
listeria reaches high numbers in
poorly preserved silage or decaying vegetation when pH >5.0
listeria in cattle
ingestion of contaminated poorly fermented silage;
often subclinical
clinical disease is most common in adult cattle
tends to be sporadic
clinical disease of listeria in adult cattle
fever, depression, CN signs, UMN signs
listeria in poultry
often subclinical
small ruminants clinical signs
sheep>goats
encephalitic and septicemia forms
clinical disease is rare in
horses, pigs, dogs, cats
transmission
foodborne
congenital
direct contact (rare)
foodboren
unpasteruized dairy products
RTE meats
undercooked beef/poultry, raw produce
