<prompt> Window period in HIV is from -Infection to appearance of antibodies in serumInfection to appearance ofviral paicles in bloodInfection to appearance of symptomsInfection to decrease of CD4 lymphocytes  <response>: It may takr 2-8 weeks to months for antibodies to appeae after infection and during pa of this periof the individual may be highly infectiousThis seronegative infective stage is known as tbe window period. REF:ANANTHANARAYAN AND PANIKERS TEXTBOOK OF MICROBIOLOGY 9TH EDITION PAGE NO-579 