The recent decision by a school board in Talbot County not to allow a school nurse to distribute condoms to sexually active teenagers {Metro, Oct. 25} could have tragic consequences.

It is unfortunately symptomatic of our muted national response to the AIDS epidemic, due in no small part to the frequent confusion of moral and health issues. As a doctor and an assistant professor of epidemiology and medicine at The John Hopkins University, I know that the promotion of condoms to sexually active teenagers is unmistakably a health issue. The arguments of those who contend that condom promotion will send a tacit message condoning teenage sex, do not stand up to close scrutiny.

First, teenagers are already widely involved in high-risk sexual behavior. It is therefore difficult to understand how condom promotion could make this any worse. In fact, condoms supplied with appropriate counseling from a school nurse on safe sex seems likely to reduce high-risk sex, rather than encourage it.

Second, if inaction continues in face of the rapidly spreading HIV epidemic then teenagers will continue to get infected, get AIDS and die in increasing numbers. To me this is the most powerful, practical argument. Teenagers will continue to have sex, that is as certain as death and taxes. Our duty is to teach them to do it safely, because their health and even their survival may depend on it.

The condom is the only AIDS ''vaccine'' available now or in the foreseeable future. A practical, logical, humane approach to the HIV epidemic demands promotion of condoms and safe-sex education. Confusion of this approach with morality will only help spread the virus and the tragedy associated with AIDS.

In closing, it is worth noting that many other Western countries have decided that AIDS prevention is a practical health issue, not a moral one. In these countries it is likely that the spread of HIV can be limited. In New York and other large U.S. cities the virus has already spread widely in young adults of both sexes, and it is beginning to appear in smaller towns and rural communities. For many, our inaction and the facile health/morality debate on condom and safe-sex promotion will mean that intervention, if it comes at all, will be too late. NEIL M. H. GRAHAM Baltimore