The concerns for himself, his family and his patients expressed by Dr. Richard L. Stokes III {"Doctors and the Treatment of AIDS," letters, Jan. 3} are understandable and in most respects even laudable. The problem is his focus on the approximately 30,000 people currently living with a diagnosis of AIDS who are seeking treatment. The implication is that if the doctor avoids these readily identifiable cases or takes heroic measures to block the transmission of the human immunodeficiency virus (HIV) while in unavoidable contact with them, he has provided adequate protection for himself and those dependent on him. Unfortunately, people whose HIV infections have advanced to the point where they have begun developing opportunistic infections or Kaposi's sarcoma and therefore formally "have AIDS" appear to be among the least infectious of all those who harbor the virus. Opportunistic infections develop after the virus has destroyed most of the body's T-4 cells and thus has, effectively speaking, eaten itself out of house and home.

The real source of concern for doctors should be the vastly larger number of people who are infected but show no readily apparent symptoms and are for the most part totally unaware that the virus is steadily reproducing within them at the expense of their immune systems. The "villain" here is the extraordinarily long incubation period of HIV -- a mean of 5 1/2 years according to one study. Incidentally, this means that almost all of the 50,000 people who have so far been diagnosed with AIDS contracted the disease in the late '70s or early '80s -- long before HIV was identified or doctors had more than the most general notions of how the epidemic was being spread and how their patients could avoid contracting it.

Several years ago, a group of researchers sat down one afternoon, extrapolated from the limited data available and came up with a guesstimate that 1.5 to 2 million people were then infected. If this was accurate at the time, it has almost certainly since doubled. Ironically enough, medical personnel should thus be most concerned with the possibility of infection from those who appear to be in the best health. Clearly the only defense is to treat all patients in accordance with the procedures and levels of sterility advocated by the Centers for Disease Control. Even with universal, periodic and mandatory blood testing (say, 240 million tests repeated twice a year -- at what cost?), designed to separate the scapegoats from the sheep, there would always be the problem, as Dr. Stokes states, of the recently infected who may not show up on currently available tests for six months or a year -- but are infectious throughout this period.

Here is one of those rare instances where ethics and science point to the same conclusion: fairness and effectiveness both dictate equal treatment for everyone seeking medical care.

ROBERT T. KEY

Bethesda