Aetna executives Ronald A. Williams and Troyen A. Brennan [op-ed, July 10] said that health insurance companies need to screen out applicants with preexisting conditions because otherwise healthy people would wait until they were sick to apply for insurance.

But there are young people with preexisting conditions who can no longer be covered by their parents' health insurance. They are often in critical need of medical care and cannot find or cannot afford insurance. If they want health insurance, they are limited in their choice of occupations, employers and states where they can live. Do we really want to assign these young people to such restricted lives?

We need a universal health-care system that spreads the risks throughout the society and away from private insurers that cover only limited portions of the population.

RICHARD M. LEVINE

Cost savings through the public Medicare plan should trump ideology and drive Congress to eliminate the huge federal subsidies to private Medicare plans. The fact that the overwhelming majority of their constituents with Medicare, Republicans and Democrats alike, prefer the choice of doctors and hospitals and health security that traditional Medicare offers over private insurance should be more than enough.

DIANE ARCHER

New York

The writer is founder and past president of the Medicare Rights Center.