Weil felix reaction is heterophile antibodies reaction due sharing of Rickettsial antigen with

Ans. is 'b' i.e., Proteus Weil felix reaction This reaction is an agglutination test in which sera are tested for agglutinins to 0 antigens of ceain nonmotile proteus strains OX -19, OX - 2 and OX - K. The basis of the test is the sharing of an alkali - stable carbohydrate antigen by some rickettsiae and by ceain strains of proteus, P. vulgaris OX - 19 and OX - 2 and P. mirabilis OX - K. The test is usually done as a tube agglutination, though rapid slide agglutination methods have been employed for screening