3. Mad Cow Disease or variant Creutzfeldt-
Jakob Disease overview:
Mad Cow Disease is to cows as vCJD is to humans.
Mad Cow Disease = Bovine Spongiform
Encephalopathy
BSE is a degenerative brain disease in cows that
comes from a prion aka misfolded protein
These prions infect proteins within the brain to
cause microscopic “holes” in the brain
4. Creutzfeldt-Jakob Disease (CJD)
Is a degenerative brain disease that affects
humans aged 45-75, but 60-65 is the most
vulnerable population
Creates a sponge-like texture in the brain
variant Creutzfeldt-Jakob Disease (vCJD)
Comes from eating beef tainted with BSE or Mad
Cow Disease
Degenerative brain disease that is known to affect
people in their 20’s.
5. Origins:
2 Hypotheses:
1st: BSE comes from the disease Scrapie
▪ Scrapie affects the lymph nodes of sheep and is also
based on Prions.
▪ Cattle ate contaminated sheep with Scrapie
2nd: BSE comes from a single cow.
▪ A sporadic case of BSE forms in a cow and is spread
through the feed.
▪ Most recent evidence suggest this is the most possible
cause
6. Genetic Factors affecting humans:
PRNP
▪ Gene that encodes the prion protein
The PRNP locus was strongly associated with risk
across several markers
▪ Basically the position of this gene on a chromosome
The polymorphic codon 129 of PRNP was the
main genetic risk factor for vCJD
(Mead, S. et. al, 2009)
7. Hard question to answer.
Practices
If BSE originated in a sporadic fashion than it
seems as though this could have happened
anywhere.
Possibly England was using a different antibiotic
than other modern countries.
▪ Recycling of antibiotic meat or even just recycling of
cattle
▪ Possibly a new mutation occurred?
8. Ireland had a significantly lower number of BSE
cases compared to England
1,353 vs. 183,841.
Ireland’s primary method to feed cattle is
predominately grass based
In U.S.A., we feed our cattle with Soybean Meal
and Cotton Seed Meal
Ban on feeding cattle with remains from other
animals
Much less expensive
3 cattle had BSE, at least 1 came from Canada
9. Farms are in rural parts of the country,
however contaminated meat is being shipped
through out England.
Preference to live in city away from farms
10. Mosquito-borne infectious disease
Caused by eukaryotic protists
Prevalent in Equatorial regions of the world
Thrives in warm rainy areas
Environment allows mosquitoes to breed
constantly
Causes headache, fever, coma, and death
11. Malaria was very prevalent in late 18th century
England: Deaths per 1,000 per year
18th 18th 20th
Century Century Century
Essex, En Essex, Garki,
gland England Nigeria
Age NonMarsh Marsh Savannah
5 44 95.3 154
6-10 6.3 9.4 15
http://www.cdc.gov/nci
11-15 6.8 10.8 10 dod/eid/vol6no1/reiter.h
16-20 8.4 12.7 6 tm
12. Question: What brought Malaria to the
marshes of England in 17th and 18th Century?
Answer: Climate change
13. The climate had naturally become warmer as
it is constantly going through waves of
warming and cooling
Why is this important now and is it a threat?
What other threats of Malaria exist as well?
14. In 1975 WHO, declared Europe “Free of
Malaria”
Mass mosquito spraying, England as well
In 1977, 83% of the world was Malaria Free,
with only Sub-Saharan Africa being affected.
As time went on, Malaria started to reappear
first in South America, tropical Asia, and
some Mediterranean countries.
15. Some theories of the resurgence of Malaria
include:
Deterioration of Vector control
Urbanization
Clearance of forests
Population increase
Resistance to insecticide
Climate change
16. Yes, with the resurgence of Malaria and
increasing global temperatures, the marshes of
Southern England could again be stricken with
Malaria
“The researchers have calculated that if global
warming continues at its current rate, some of
these same areas could once again become
breeding centres for malaria for up to four
months each year by the end of this century.”
http://news.bbc.co.uk/2/hi/health/1775427.stm “UK faces summers of malaria” (2002)
17. If Malaria does come back to England, likely to
occur in:
Southern Marshes
Northern England will be safer due to cooler
temperatures
No imminent outbreak about to occur, however
there is a very strong possibility that it can return
to the English Marshes
Best way to control:
IPM
18. A protozoan parasite found in contaminated
water
Can colonize and reproduce in the intestines of
humans and other vertebrates
Develops into an oocyst which is extremely hard
to destroy
Spread through the fecal-oral route
Main symptom is diarrhea
Can be fatal in immunocompromised people such as
AIDS patients
20. Crypto has been the most prevalent
infectious water-borne disease in the past 10
years in England.
(Jones, M. et al, 2006)
In England and Wales between 1992 – 2003,
Crypto was responsible for 70% of all water-
borne outbreaks
(Smith, A. et al, 2006)
22. Swimming Pools contaminated with Crypto:
Regular treatment should reduce risk
Nearly impossible to prevent point-source
infection
Crypto oocysts can been introduced by accidental
fecal release by young children
Parents should prevent children with
gastrointestinal distress from swimming in pools
(Smith, A. et al, 2006)
23. August 2003
Outbreak of Crypto in children following a visit to
an “adventure park” in SW Rural England
Several activities included water, water rides, and
contact with farm animals
Took water samples at various locations
Took stool samples of the farm animals
▪ (jones, M et al, 2006)
24. 91 children got sick
Median age was 6
94% reported diarrhea
64% vomiting
62% abdominal pains
51% nausea
23/27 water samples contained various amounts
of Cryptosporidium
Due to failure of communication between Park
and Researchers, they were unable to test
animal stool samples
25. Recirculation of contaminated water
Poor filtration and disinfection
Also, nearly all the children did not show
symptoms until 2-6 days following visit.
Due to incubation time, children could easily
affect any family members or friends without
knowing. i.e. Swimming Pools
26. Adventure park was in a rural area
Residential pools are more likely to be
outside of the city, in more rural and
suburban areas.
People in rural areas are more likely to have
contact with animal feces, farms
Rural parts are more likely to be affected with
Cryptosporidium
27. Potentially lethal infectious disease
Caused by bacteria, attacks the lungs
Spread through air when people with an
active infections sneeze, cough, or transmit
saliva through air
Most infections are asymptomatic and are
latent
1 in 10 will progress to active disease and
>50% will die if left untreated
Was the biggest killer in UK in 19th century
29. 2005, TB cases rose 10.8% from previous year
in England
London recorded 3,479 cases, up from 3,129
in 2004
The highest proportion of cases - 38% - were
reported among people from an
Indian, Pakistani and Bangladeshi ethnic
background.
Levels of TB in the UK-born population have
remained stable
30. Foreign born population accounted for 5,310
cases in England in 2005
However on 22% arrived in England in past 2
years
This suggests a combination of:
Latent infections
New infections acquired from infected person in
England
Travel to other countries where TB is common
31. Extremely high amounts of TB in countries a
foreign-born UK citizen would travel too.
India, Bangladesh, Many African countries as
well
WHO: South East Asia accounts for 35% of
World’s TB rate
WHO: Africa accounts for 30% of World’s TB
rate
32. According to 2001 UK Census:
1,053,411 Britons had full Indian ethnicity.
99.3% resided in England
491,300 resided in London
1,148,738 Britons categorized themselves as
Black British
1,100,000 resided in London
33. This means that the chances of someone
from England traveling to a region where TB
is prevalent is extremely high
Many of foreign born people are living in
urban-London, making the urban region
extremely susceptible to TB
Prevention and education for those traveling
to high TB areas is key
