TOKYO — Four years ago, Kyoko Kawabe took her 17-month-old son to the doctor for what was supposed to be a routine vaccination. A few weeks later, he had high fevers and convulsions diagnosed as meningitis. After three weeks in the hospital, the meningitis seemed cured, but the weakened toddler died of pneumonia.

"They took a healthy boy and gave him a shot of poison," said Kawabe.

The same "poison" changed Hideo Ueno's life when his daughter Hana received the vaccination three years ago before her second birthday. She also contracted encephalitis--a brain infection that can be fatal or cause serious paralysis. The child survived, but she is partially paralyzed and cannot speak.

The family has moved to be close to the hospital and Ueno's wife has quit her job to devote herself full time to taking care of Hana.

The two families are among many who have become victims of a disastrous government effort to support Japan's pharmaceuticals industry. Although safe products were already available in the United States and Europe, the government, industry and academic elite banded together to develop a Japanese vaccine and promote its use based in large part on safety studies of a similar, but not identical, vaccine made by Rahway, N.J.-based Merck & Co. and other drug companies.

In fact, the Japanese called their vaccine MMR, a Merck trademark. Studies showed that the Merck product has been used to inoculate more than 100 million children, with no confirmed cases of serious side effects.

Last week, following reports of abnormally high levels of disease among children who were given the Japanese vaccine to prevent measles, mumps and rubella, Japan's Ministry of Health and Welfare halted its use.

The issue has drawn attention in Japan because of charges that the government continued to promote the vaccine long after its dangers had become clear. What has yet to be reported is that the government promoted the development and use of the risky vaccine even though it knew a better alternative had been available overseas since 1975.

As part of a broader, nationalistic effort to promote its still- weak pharmaceuticals companies, Japan wanted its own domestically produced version of MMR.

"Rather than use foreign products, we wanted Japanese products because they are of better quality," said a woman who answered the phone at the Assn. of Biologicals Manufacturers and declined to be identified.