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anorexia, chest pain, and general malaise, 
which are normally absent from avian schisto- 
some cercarial infection. Nevertheless, the 
Formosan strain of S. japonicum did not de- 
velop to maturity in the volunteers and con- 
sequently did not result in a typical schisto- 
somiasis. There were no experiments on 
repeated infections in these volunteers to 
determine hypersensitivity reactions. 
Japanese investigators had long suspected 
that S. japonicum ("human strain”) might 
cause cercarial dermatitis. In 1909, Kobayashi 
studied the relations between "kabure,” en- 
demic dermatitis, and schistosomiasis japo- 
nica (Faust, 1924£). Recently Ishii and Ogawa 
(1952) reported that it was possible to pro- 
duce dermatitis in rats with the cercariae of S. 
japonicum ("human strain”) by repeated ex- 
posure to the cercariae. Characteristic lesions 
included macules, papules, erythema, edema, 
and vesicles. However, Hunter and his associ- 
ates (1956), using mice, hamsters, and rab- 
bits as experimental animals, were unable to 
repeat these results or similar Endings re- 
ported by other workers and so concluded 
that the selection of the proper experimental 
hosts for studies on immunologic responses to 
schistosome infection is of critical importance. 
6. Malaya and the Philippines 
Buckley (1928) demonstrated that the 
dermatitis known as "sawah itch” in Malaya 
was caused by the cercariae of Schistosoma 
spindale Montgomery, 1906, obtained from 
Planorhis pfeifferi. Normally S. spindale causes 
serious schistosomiasis in mammals such as 
cattle, sheep, goats, horses, antelopes, and 
water buffaloes in India, South Africa, and 
Sumatra. 
Another example of a mammal-infecting 
schistosome which causes dermatitis in man 
is Schistosomatium douthitti (Cort, 1914). This 
organism is found in the United States as a 
parasite in deer, mice, and muskrats. 
A fruitful field for research would be a 
comparative study to determine the differ- 
ences between the mammalian schistosomes, 
which can cause dermatitis in man (like S. 
spindale , S. douthitti ), and the dog-infecting 
strain of schistosome (S. japonicum ), which 
apparently does not cause natural cercarial 
dermatitis (koganbyo) among Formosan 
farmers. 
Recently a bird schistosome belonging to 
the " elvae ” group of cercariae was described 
by Sandosham (1953) as the cause of sawah 
itch in the Ayer-Lunging district, Negri Semi- 
Ian, and the intermediate host was identified 
as Lymnaea rosseana Mabille. This dermatitis - 
producing cercaria was named Cercaria Ma- 
laya /, and an unsuccessful attempt was made 
to infect chickens with it. 
Cercarial dermatitis in man in the Philip- 
pines has not been studied to any extent, 
probably because of the intense efforts on the 
part of the medical scientists to control the 
spread of schistosomiasis japonica. Tubangui 
(1947) listed Austrobilharzia bayensis Tuban- 
gui, 1933, as a schistosome from the mesen- 
teric vein of a snipe, Capella gallinago galli- 
nago . This finding is encouraging for those 
who are interested in further host examina- 
tions for the presence of avian schistosomi- 
asis, especially in the sea and shore birds of 
the Philippines. 
7. New Zealand 
According to Macfarlane (1944, 1949^, 
1949^) the reports of swimmer’s itch derived 
from lakes Hawea, Te Anau, Alexandrina, 
and Rotoiti, and from several lakes in the 
Rotorua district, have not been confirmed. 
However, Macfarlane recovered schistosome 
cercariae from snails in lakes Wanaka, Hayes, 
and Wakatipu in the South Island. The etio- 
logical agent causing experimental dermatitis 
has been described and named Cercaria longi- 
cauda Macfarlane, 1944. The snail intermedi- 
ate hosts are: Myxas ampulla , M. arguta , and 
Limnaea alfredi. The molluscan hosts in Lake 
Wanaka lived in beds of the pond weed 
Myriophyllum robustum and also on Isoetes spp., 
J uncus spp., and Potamogeton polygoni folium. 
In lakes Wakatipu and Hayes there were 
