Two U.S. doctors from the Centers for Disease Control in Atlanta have concluded that the mysterious illness that affected hundreds of Arab schoolgirls in the West Bank this spring was caused by "anxiety" and spread by psychological factors, the Israeli Health Ministry announced tonight.

Ministry Director General Dr. Baruch Modan made public at a news conference a summary of the U.S. doctors' findings, which said there was no evidence that the illness was caused by poison as had been charged by Palestinians in the Israeli-occupied territory.

The report also said there was no evidence to support charges by Israeli officials that many of the schoolgirls had deliberately fabricated the illness' symptoms, which included headache, dizziness and nausea. Nobody died from the illness.

In Washington, the State Department released the text of the 47-page report.

Reports of the illness set off disturbances in several parts of the West Bank and sparked angry accusations by Palestinians that Israelis had poisoned the schoolgirls. The most serious disturbance, in which at least two Israeli soldiers and an Arab youth were injured, occurred on Easter Sunday after reports of what proved to be the illness' last wave in the villages of Yatta and Anabta.

The American doctors, Philip J. Landrigan and Bess Miller, spent two weeks here at the invitation of the Israeli government earlier this month after more than 900 West Bank residents, most of them adolescent girls, were struck by the illness. According to the summary of their report, which included excerpts from the text, the first cases may have been caused by low concentrations of hydrogen sulfide gas that were found in a latrine near the school in the village of Arraba near Jenin.

But the doctors said that medical tests from other areas where the illness was reported "failed to detect the consistent presence of any environmental toxins."

"We conclude that this epidemic of acute illness was induced by anxiety," the report said. "It may have been triggered initially either by psychological factors or by subtoxic exposure to hydrogen sulfide. Its subsequent spread was mediated by psychogenic factors. Newspaper and radio reports may have contributed to this spread.

"The epidemic ended after West Bank schools were closed. We observed no evidence of malingering by the victims or of deliberate fabrication of symptoms."

The report added that there was "no evidence of reproductive impairment in affected patients." One of the charges made during the epidemic was that Israeli authorities were poisoning Arab schoolgirls to make them sterile as part of a plan to reduce the West Bank's Arab population.

The doctors' report said that their findings were based on physical examinations of patients, scientific tests including analysis of blood and urine samples, and studies seeking possible toxins in the environment.

It acknowledged that a possible shortcoming was that the examinations and tests were conducted between two days and several weeks after the onset of the illness. However, the doctors did have the opportunity to examine patients suffering "acute and highly painful" bouts of the ailment after they initially fell ill.

Modan said the findings of the Centers for Disease Control confirmed the Israeli Health Ministry's initial conclusions, which were that the epidemic was a case of a "mass phenomenon" or "mass hysteria," which he said is "well known in the medical literature."

He said he did not dispute the conclusion that the victims suffered from genuine symptoms of illness despite charges by Israeli authorities in the West Bank that they were fabricated at the instigation of Palestinian nationalists.

"I agree with and accept the basic language of this report," Modan said.

According to the summary of the report, 943 cases of the illness were reported in the West Bank between March 21 and April 3. It said 660 of the victims were adolescent schoolgirls.

Modan said most of the other victims were women older than adolescents. He said fewer than 10 Israelis in the West Bank complained of the symptoms of the illness.