March, 1954] A
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F. indica was hitherto mistaken to be F. hepatica or F. gigantica. The former might
occur in the cold Himalayan region, where Bhalerao records to have found its snail-
intermediary, Limnaea truncatula, but the writer is dubious about the occurrence of
true F. gigantica in India.
Demonstration of some fasciola-like eggs in the faecal sample, examined from
an elephant in the area, points to the occurrence of Fasciola jacksoni Cobbold [1869].
CONTROL
The knowledge regarding the nature, incidence and distribution of the disease
in a circumscribed area of the State should prove of value in formulating control
measures. It has been shown that the vagaries of the river Kosi are to a large extent
responsible for providing ideal habitats for the molluscan vectors of the parasite.
Hence, any attempt to harness this river may go a long way not only in converting
the country from a wilderness of sand and swamp to a fruitful landscape but also in
driving out the notorious parasites. It is gratifying to note that efforts are being
made to dam the river near the point of its emergence from the hills. In carrying
out the scheme proper drainage of the area by providing suitable channels without
leaving behind water-pockets for the snails, should not escape consideration.
Meanwhile, control measures should be directed against reducing the incidence
and intensity of infection by resorting to principles which are generally adopted for
such conditions. There are large marshy tracts whose molluscicidal treatment is
impracticable and hence prevention of the disease must depend upon well advised
grazing practice. In this connection it becomes imperative that the optimal condi-
tions of life for the snails in question and the factors governing their infection with
the miracidia, development of the parthenitae in them and the emergence, encyst-
ment and longevity of the cercariae encysted on herbage under natural conditions be
studied in details.
Mass treatment of susceptible animals with carbon tetrachloride is advisable
but it must be well planned on scientfic basis. Some investigators have found it
ineffective in acute and sub-clinical infections. The drug may kill all the adult
flukes living in the bile ducts at the time, but there will usually be a few young forms
migrating, which are not affected and for this reason repeated treatment is essential.
This programme of work should be initiated in the higher regions and worked
down to the lower levels without missing any infected animal; and the treatment be
repeated at least six months later. Random dosing of animals here and there
without any planning may be ineffective owing to the chances of re-infection. Con-
trol of wild animals, which probably act as reservoirs of the disease, should also receive
attention simultaneously. This scheme of treatment together with planning grazing
practice will break the chain in the life cycle of the parasite and thereby control the
spread of the disease, which may die out completely in course of time.
SUMMARY
1. A survey of the endemic areas of nasal schistosomiasis and fascioliasis in the
State of Bihar (India) was undertaken to study the factors having a bearing on their
occurrence. It revealed an interesting relationship of the diseases to topographical
and other factors, which are discussed in the report.