"AIDS has spread both numerically and geographically." What does the statement mean?

Since the first reported case of AIDS in the United States in 1981, the disease has spread both numerically and geographically. According to the World Health Organization, 28 million people in the world already carry the AIDS virus. What is most alarming is that the disease is not only found in homosexuals, prostitutes or drug abusers, but also in innocent people, including children. In some countries in Africa, the situation is very serious indeed.
    The AIDS virus, now known as HIV, passes from mother to child in uterus, during birth, and possibly through breast-feeding. Because of the high HIV-positive rates among pregnant African women, the AIDS epidemic among children will only grow worse. In Kinshasa, Zaire, for example, eight percent of the pregnant women in a prenatal clinic tested HIV-positive.
    As many as half the children born to HIV-positive mothers will themselves be infected. Right now in some parts of Africa, five percent of new-borns are HIV-positive, and one-half to two-thirds of those will develop AIDS within two years. In Rwanda, for example, 22 percent of AIDS victims are children. And this year 6,000 Zambian children will be treated for AIDS. Thus AIDS endangers not only this generation of Africans, but the next as well.
    Besides mother-to-child, AIDS is transmitted to innocent victims in another way. A European doctor in Zambia told this story: Robbers broke into the home of a family and, before escaping with the family’s valuables, shot the two daughters. In saving the young women’s lives, doctors gave them blood transfusions. The blood, however, contained the AIDS virus. Now one of the sisters has AIDS and is dying, and the other is HIV-positive. It has been estimated that over 10 percent of Africans who are HIV-positive are believed to have received the virus through infected blood. In Central Africa that could mean over half a million people.
    AIDS infects health care workers, too. The Center for Disease Control (CDC) not long ago reported three AIDS infections in health workers, whose skin was exposed to the blood of AIDS patients and have become infected with the AIDS virus. They stressed that there is no evidence that the AIDS virus can pass through intact skin or spread by casual contact. While they do not know the exact route of transmission, CDC officials said that in these three cases the virus may have passed through chapped or inflamed areas of unprotected skin.