[Course of HIV2 seroprevalence at the National Hospital of Niamey (Niger)].

About the 25,368 serological tests done among the different groups of the population at the biological laboratory of the National Hospital of Niamey from March 1987 to May 1990, the author studied the seroprevalence evolution of the infection HIV2. A regular fall for the HIV2 appeared in this period. The author tries to explain this fall of the HIV2 in a country newly infected by the HIV by the lower infectivity of the HIV2 and/or a failure to adjust of this virus in Niger.