Social Security officials said yesterday that they do not plan to expand the definition of people who will automatically receive disability benefits because they have AIDS, even though the government's Centers for Disease Control recently issued a new and broader definition of what constitutes having the deadly viral infection.

David Rust, associate commissioner for disability, said the Social Security Administration will continue to use the rule that a patient must have "fully developed AIDS" in order to qualify more or less automatically for disability benefits.

In fully developed AIDS, the patient is debilitated and appears likely to die within a relatively short period. Conditions such as infections, cancer and pneumonia are also present, Rust said.

AIDS, acquired immune deficiency syndrome, is a rapidly spreading viral infection that impairs the body's ability to fight off other diseases. It is the subject of a major international conference here this week.

Rust said the Centers for Disease Control had recently expanded its definition of AIDS to include persons who have less-developed cases in earlier stages -- many of whom are not yet so stricken that they cannot work. He said the new CDC definition appeared to be aimed in part at improving the ability of scientists to track the spread of the disease.

In cases where the AIDS condition is not fully developed, Rust said the Social Security Administration will continue to require medical workups of various types and examination of the individual's ability to work before deciding.

Rust said he could not say precisely how many people would qualify if the new CDC definition were used as a basis for disability grants but there probably would be a substantial increase in the number of those eligible for disability benefits if it were used.

About 14,000 people to date have been granted Social Security or welfare disability benefits as a result of having fully developed AIDS.