PROCAARE: BASIC SCIENCE--SUBTYPES

["Gerard J. Nau (Jerry)" <gnau@usa.healthnet.org>]

KEYWORDS:  SUBTYPES/ O-TYPE/ SEROLOGY/ WEST-CENTRAL AFRICA
==========================================================

Reference:   Rayfield M.A., P. Sullivan, C. I. Bandea, R. A. Otten, C.P. 
Pau, D. Pieniazek, S. Subbarao, P. Simon, C. A. Schable, A. Wright, J. 
Ward, and G. Schochetman. (1996)  HIV-1 group O virus identified for the 
first time in the United States.  Emerging Inf Dis Vol.2 No. 3.  
At:  http://www.cdc.gov/ncidod/EID/eid.htm

This report documents the first case of group O HIV-1 virus in the United 
States.  A woman from West-Central Africa was identified by the CDC 
sentinel surveillance program for unusual HIV variants.  She presented 
with a clinical picture compatible with HIV-1 infection but had 
repeatedly inconclusive testing by EIA, Western blot, and standard PCR 
analysis.  It was only through direct culture of virus and the use of 
group O-specific PCR primers that the infection was confirmed.

European researchers identified strains atypical for their geographic 
location in 1994.  The Group O strains appeared to be circulating in 
Cameroon and Gabon; it appears international travel is a common thread in 
these infections.  This report raises a note of caution for the 
limitations of the clinical tests for HIV infection that are currently 
available.  It also raises the stakes in the push for a vaccine strategy 
that will be applicable for multiple geographic areas.