Bilharzia ova in cervical smears a possible additional route for the passage of ova into water

1,901 slides from 3 clinics were examined for bilharzial ova and miracidia and 44 were found to be positive. The percentage of positives was higher in the Post-Natal group than in Family Planning or Gynaecological Out-Patients groups. This difference may be partly because of increased vascularity associated with pregnancy. The presence of viable ova as well as miracidia in some of the cases was demonstrated and their importance as a further possible mode of transmission of the disease is emphasized. This applies to both S. haematobium and S. mansoni. Some variation in the degree of excretion of ova, depending on the stage of the menstrual cycle, was noted in a small number of cases on which data on the menstrual cycle were available. Further work is being carried out on this point.