Schistosomiasis Hope this will help! :)

1. SCHISTOSOMIASIS
FEBRUARY 24, 2015

2.  Schistosomiasis, also called
bilharzia or bilharziasis,
snail fever, or Katayama
fever.
 Schistosomiasis is a disease
caused by parasitic worms
of the Schistosoma type.

3. SPECIES OF SCHISTOSOMA
 S. japonicum- causes Asian
intestinal schistosomiasis.
 S. mansoni- causes intestinal
schistosomiasis that lodges in the
blood vessels.
 S. haematobium- causes urinary
schistosomiasis.
 S. intercalatum and S. mekongi

4. SNAIL HOSTS
The different species of Schistosoma have
different types of snails serving as their
intermediate hosts; these hosts are as follows :
Biomphalaria for S. mansoni
Oncomelania for S. japonicum
Tricula (Neotricula aperta) for S.
mekongi
Bulinus for S. haematobium and S.
intercalatum

5. S. japonicum
S. mansoni

6. S. haematobium
S. intercalatum S. mekongi

7. INCUBATIONPERIOD
 4-6 weeks usually pass before egg
production begins.
 Cercariae reach the portal venous
system several days post-infection .
 Toxemic schistosomiasis may develop 6-8
weeks post infection.
 Urinary schistosomiasis may develop 10-
12 weeks post infection.
 Adult schistosomes may live 20 to 30
years.

8. MODE OF TRANSMISSION
 Eggs hatch releasing miracidia
(larvae/larval stage)
 Miracidia penetrate snail tissues—
Oncomelania hupensis (freshwater
snails)
 Cercariae released by snail into
water ang free-swimming which
penetrates the skin especially in cuts
or wounds.

9. Cercariae lose tails during
penetration and becomes
schistosomulae
After circulation, the
schistosomulae migrate to
portal blood in liver and
mature into adults.

10. Paired adult worms migrate to:
Meseneteric venules of
rectum (laying eggs that
circulate in the liver and shed
in stool) by S. japonicum and
S. mansoni
Venous plexuses of bladder
and shed in urine by S.
haematobium

12. SIGNSAND SYMPTOMS
Symptoms vary with the species of
worm and the phase of infection.
 Heavy infestation (many parasites)
may cause fever, chills, lymph node
enlargement, and liver and spleen
enlargement.
 Initial invasion of the skin may cause
itching and a rash (swimmer's itch). In
this condition, the schistosome is
destroyed within the skin.

13. Intestinal symptoms include
abdominal pain and diarrhea
(which may be bloody).
Urinary symptoms may
include frequent urination,
painful urination (dysuria),
and blood in the urine
(hematuria).

14. COMPLICATIONS
Gastrointestinal bleeding
GI obstruction
Malnutrition
Schistosomal nephropathy
Renal failure
Pyelonephritis
Hematuria

15. Hemospermia
Squamous cell bladder cancer
Sepsis (Salmonella)
Pulmonary hypertension
Cor pulmonale
Neuroschistosomiasis -
Transverse myelitis, paralysis,
and cerebral microinfarcts

16. Infertility
Severe anemia
Low ̶ birth-weight babies
Spontaneous abortion
Higher risk for ectopic
pregnancies
End-organ disease

17. Portal hypertension
Obstructive uropathy
Pregnancy complications
from vulvar or fallopian
granuloma
Carcinoma of the liver,
bladder, or gallbladder

18. SCREENING TESTS
KATO-Katz- is a laboratory method
for preparing human stool samples
prior to searching for parasite eggs.
Urine filtration method- test for the
presence of S. haematobium.
Blood tests- are occasionally useful in
supporting the diagnosis or assessing
the severity of schistosomal infection.
Rectal Mucosal Biopsy

19. TREATMENT AND CURE
Praziquantel- used to treat
all kinds of schistosoma
species
Steroids (Corticosteroids) are
used to relieve the symptoms
of acute schistosomiasis.

20. Schistosomaspecies infection
Praziquanteldose and
Duration
Schistosoma
mansoni, S.
haematobium, S.
intercalatum
40 mg/kg per day
orally in two
divided doses for
one day
S. japonicum, S.
mekongi
60 mg/kg per day
orally in three
divided doses for
one day

22. SIDE EFFECTS OF PRAZIQUANTEL
More common
Drowsiness
Increased sweating
General feeling of discomfort or
illness
Nausea or vomiting
Less common
Hives or Urticaria

23. PREVENTION
Avoid swimming or wading in
freshwater especially those
with open wounds or cuts
Drink safe water
Always boil or filter water
even for used for bathing

24. CONTROL
Mass treatment of entire
communities and targeted
treatment of school-age
Improved sanitation could
reduce or eliminate
transmission of this disease