One health : Zoonosis Cryptosporidiosis in ruminants

1. CRYPTOSPORIDIOSIS AND
BIOSECURITY
Brigitte Duquesne, DVM
WBC 2018 SAPPORO

2. Cryptosporidiosis: a global,
emerging, neglected zoonosis

3. Focus on calves
cryptosporidiosis

4. Cryptosporidiosis in neonatal calves
• Other enteropathogens: rotaviruses,
coronaviruses, E.coli
=> Faeces analysis for differential
diagnosis
• Age: 7-13 day old calves
• Clinical signs:
 watery, mucous diarrhea
 high morbidity / low mortality
 recovering after 5-6 days
 scouring more severe if mixed infection
• Immunity after prior exposure
Causal agent : Cryptosporidium parvum

5. Histopathology
Target: enterocytes
Intracellular but
extracytoplasmic
(vacuole)
Villi atrophy and loss of epithelial
cells leads to diarrhea and
malabsorption

6. Slide 6
Life cycle
6
1
2. SPOROGONY
3.MEROGONY
Ways of
autoinfection
4.GAMETOGONY
All the stages inside the host
Excreted oocysts directly infective

7. Disease transmission :Faecal-oral route
Presence of oocysts ?

8. Difficulties to control cryptosporidiosis
• Long survival of oocysts in a suitable environment
• Resistant to commonly used disinfectants
• Can survive several months in cool, moist environments
• Low infective dose
• From as few as 10 oocysts, infected animals can rapidly
shed up to billions oocysts.
• Therapy options
• No vaccine
• Many molecules tested – Only 2 with satisfactory results:
Halofuginone lactate (as prophylactic, EU licensed)
Paromomycin (UK licensed)

9. Cryptosporidiosis is a zoonotic disease
which can spread rapidly within a farm /
a group
Importance of biosecurity

10. What is biosecurity ?
BIO
SECURITY
LIFE
PROTECTION
Strategies, processes
and knowledge
to prevent disease
incursion and the
spread of infectious
pathogens in a range
of domains where
disease occurs
amongst humans,
animals and plants or
more broadly within
an environment
(Koblentz 2010)

11. Biosecurity on livestock farming
C. Saegerman,F.DalPozzo,
MF.Humblet
IJPH - 2012, Vol 9, Nb 2

12. Slide 12
Recommended measures to control
cryptosporidiosis on farm

13. Biosecurity principle :separation of high and
low risk animals and environment
• Never mix new born calves with calves older
than 3-4 days => Optimal = to rear them in
individual pens for at least the first 2 weeks
• House calves of same age in small groups in
suitably prepared pens! Larger animal
groups pose higher risks
• Quickly identify calves with diarrhea and
isolate sick calves (hospital pen, till a week
after scouring stops)

14. 14

15. Biosecurity principle : Reduction of the
general infection pressure
• If possible, spread out the calving period
• Importance of hygiene : calving pens and
calf rearing pens /houses thoroughly
cleaned and left free of animals for at
least 3-4 months before the new calving
season .
Dessication is important in inactivating
C.parvum oocysts

16. Pens and houses
Hygiene procedure
 Importance of
personal protective
equipement
(zoonotic pathogen!)
 Remove dried faeces
and other dirt from
floors, walls, rails..(!
Cracks and crevices)
 Wash all surfaces /
steam cleaned
 Use of disinfectant (!
Contact time)
 Rince and left to dry
 Left empty of
livestock (3-4
months!)

17. • Biosecurity principle : identification of the
transmission routes (not all are of equal
importance)
• On farms where cryptosporidiosis is a
recurrent problem : environment / animals
( as seen before/ management and
hygiene measures)
• In cryptosporidiosis-free herds : introduction
of infected calves  no purchase of animals
younger than 2 weeks or from a crypto-free
herd
• Humans: anyone in contact with the calves
• Environment : other animals, water....

18. Risk is a combination of
probability of transmission and
frequency of occurence of
transmission routes

19. Prevention of human transmission from one group to
another group of calves
 Anyone in contact with
the calves should
wash their hands,
change their clothes
and footwear after
handling sick calves;
 Animals handlers :
Additional precaution
= to feed youngest
calves first, work up
by age groups
 Sick calves should be
handled last (care,
feeding )
19

20. Slide 20
At Minimum

21. Prevention of human infection
Humans become infected
through contact with
infected animals
an through ingestion of
contaminated food and
water
 Animal handlers, farmers, veterinarians
should be mindful of the dangers of
transmitting cryptosporidiosis to their
family and the wider community
adherence to strict sanitation and
hygiene protocols
 Especially dangerous for young children,
immunocompromised and elderly adults
should not be allowed to have contact
with sick calves

22. Preventing surface and ground water contamination
Farmers should be very
careful when disposing of
slurry and dung from calves
infected with C. parvum
They can be source of
water contamination!
DO NOT spread
o On wet pasture
o On fields with a large scope
o Close to a ditch or river
Only spread according to regional
rules

23. Conclusion Because of its substantial
economic impact in farms and
to prevent the spread of a
zoonotic agent, the control of
cryptosporidiosis remains a
major challenge for a successful
One Health response.
• The vet practitioners play a
key role in communicating
and implementing
biosecurity measures on
farm: they should inform the
livestock owners of the
hazards that result from
contact with visibly and
invisibly infected animal and
provide them the basic
knowledge of sanitary
measures required to protect
people and environment

24. Professor B.Losson
Dr MF. Humblet
ACKNOWLEDGEMENTS