THE CASE OF 10-month-old Ashley Snead has focused much attention on individuals who provide day care services. The child died of poisoning from a prescription drug while in the care of Martha E. Guba, who had been hired by Ashley's parents as a baby sitter. In Virginia, no licensing or regulation is required to care for up to five children in a home, in addition to the provider's own children.

Should that change? Some Virginia legislators say no. People who are dangerous or incompetent will always slip through, they argue, regardless of tight standards. They also doubt the importance of criminal records checks for the same reason. More regulation, they add, would also discourage people from entering the day care business at a time when providers are already in short supply. But those arguments are rather weak. Should the state refuse to build a more secure prison because some inmates will escape anyway? People who are discouraged by higher standards shouldn't be in the day care business.

The state of Maryland does more. Registration, a home health and safety inspection, three references and a check for criminal records or pending charges are required for all day care providers. Arlington and Alexandria have similar requirements. Fairfax, Prince William and Loudoun counties have voluntary registration. But registration and regulation provide no safeguards unless they are policed. Time and time again, one hears about the crucial bit of personal history, but only after it is too late. Mrs. Guba had been convicted of neglecting her own two children in 1968, but she was on a list of day care providers kept by the Fairfax County Office of Children. To get on that list, providers must agree to a background check for any record of child abuse or neglect.

Only 3 percent of all public and private work places offer financial help for day care. Less than 2 percent of all private employers sponsor their own day care services. That leaves parents with few options other than trying to be much more careful. Day care isn't having some teen-ager over to baby-sit a few nights a week. It is far more serious, sustained work. Anyone worth hiring should meet state and local standards and come with the right credentials.