* This đocument is one in a series of papers (PDP/85. 1, 85.3, 85. 4, 85. 5) which have been
prepared by the WH0 Parasi tic Diseases Programme arid which are intended to provide up-
to-date information on technical, aspects çf intestira I parasi tic: infections control. According
to the advances in technology and as experience accumula tes in national control
programmes, these documents will be revised. Inquiries and comments may be dira: tėd to
Director, Parasitic Diseases Programme, World Health Örganization, 1 2ll Geneva 27 …