Scrub typhus is positive for: (A) OX K, (B) OX 2, (C) OX K and OX 19, (D) OX 19 only
Answer is A. Scrub typhus aka chigger borne typhus is caused by orientia tsutsugamushi.In a heterephile agglutination test(weil Felix reaction), the sera of scrub typhus patients agglutinated only OX K strain of proteins mirabilis without getting agglutinated with OX 19 and OX 2 ...as some rickettsiae and ceain strains like OX K ,OX 19 and OX 2 of proteus share alkali stable carbohydrate antigen Ref: Ananthnarayan and paniker's microbiology 10th edition