Species typically involved: S. mansoni, S. japonicum, less often S. haematobium
Incubation period: varies from 1 to 12 weeks, being shorter in a non-immune person
Clinical features:
(1) There is history of environmental water contact in an endemic area.
(2) The patient presents with an acute febrile illness, malaise, rigors, and sweating.
(3) The patient may develop:
(3a) general myalgia
(3b) headache
(3c) an urticarial skin rash
(3d) lymphadenopathy
(3e) anorexia and/or nausea
(3f) abdominal discomfort
(3g) loose stools or diarrhea
(3h) cough with rales
(3i) mild hepatomegaly with tenderness.
(3j) mild splenomegaly
(3k) cerebral symptoms
(3l) a spinal cord syndrome
(4) The syndrome tends to be more severe in a non-immune person, typically a traveler from a non-endemic country, but may occur even in a person previously exposed.
Laboratory features:
(1) Eosinophilia is common.
(2) Stool examination for ova and parasites may be positive.
(3) Serologic testing should eventually be positive but may require a convalescent sample.
