THE APPLICATION OF THE HAEMAGGLUTINATION TEST TO A STUDY OF THE IMMUNITY TO MALARIA IN PROTECTED AND UNPROTECTED POPULATION GROUPS IN AUSTRALIAN NEW GUINEA.

The formolized tanned sheep erythrocyte haemagglutination test has been applied to an immuno-malariometric study in Australian New Guinea to determine whether the haemagglutination titre reflects a subject's immune state and to measure the effect of malaria control operations on a population's immunity. Two population groups were studied-one (unprotected) living in holoendemic malaria conditions, the other (protected) living in an area subject to malaria control measures for four years.An increase in both serological positivity rates and geometric mean titres among the unprotected group with increasing age suggests that the test does serve to assess the state of immunity; the corresponding rates were much lower in the protected population, particularly among the children.The authors foresee the possible use of the haemagglutination test as a supplement to other procedures in assessing the progress of a malaria campaign. They, note, however, that more immuno-malariometric studies on populations subject to different degrees of malaria endemicity will need to be carried out before the relationship between the immune state and serological results can be clearly established.