Los Angeles County health officials reported 129 new cases of AIDS during May, bringing the total number of confirmed cases to 3,217, with 1,981 deaths. There were no new cases in children reported in May. In addition to the known cases, another 132 reports are pending investigation, the Department of Health Services said. Seventy percent of the victims in the county are white, 15% Latino, 14% black and 1% other races. Homosexual and bisexual males continue to be the largest group of AIDS patients, with 91% of all reported cases falling into that category.