DAY-CARE CENTERS ARE LINKED TO SOME DISEASES OF CHILDREN

Day-care centers have become ''networks'' for spreading diarrhea, dysentery and other intestinal diseases to children and their parents, causing outbreaks ''reminiscent of the presanitation days of the 17th century,'' a doctor reports.

The problem is too widespread to be solved by case-by-case treatment and diagnosis, Dr. Stanley H. Schuman wrote in Friday's issue of the Journal of the American Medical Association.

''We don't have enough vaccine to prevent the spread of infections in day-care facilities,'' Dr. Schuman said in a telephone interview. ''We don't have the medical dollars or the public health dollars. We have to go back to the basics of sanitation.''

The pattern, he said, is a throwback to conditions in 17th century Europe, when doctors realized the link between poor sanitation and certain diseases although they did not understand the biological cause of the diseases. Factors in Spreading Disease

Dr. Schuman, a professor at the Medical University of South Carolina in Charleston, said he believed these were factors in the problem:

- Day-care workers ''develop a casual, tolerant attitude toward frequent lapses in sanitary routines,'' even those as simple as washing hands.

- Public health officials ''tend to accept little clear-cut responsibility for day-care operations.'' In addition, regulations vary among states and money is sometimes inadequate for strict enforcement of the rules.

- Day-care centers often serve more meals than a restaurant on a given day, but proprietors sometimes have little training in handling food.

- Children enter and leave day-care centers in an erratic pattern, ''insuring maximum mixing of infected and susceptible'' children.

- Children under 6 years of age sometimes carry infections that they transmit to their parents without showing any symptoms themselves.