About 100 health volunteers on Thursday gathered at the Public Health Ministry to oppose organisational reforms.
The volunteers expressed concerns the ministry had abandoned primary health care at community level.
The move came after the ministry reduced the number of Health Service Support Department (HSS) regional health offices from 14 to 12 as part of restructuring moves which took effect on Oct 1.
Rungrit Ruangrung, a representative of village health volunteers in the North, said he was afraid the changes would harm primary health activities at community level.
He said his group was also afraid the director of the regional health offices would not support the work of health volunteers.
Mr Rungrit urged ministry executives to take into account volunteers' opinions before making any changes to the structure that could affect their work.
"Changes in public health policy must come from stakeholders," he said. Meanwhile, HSS's deputy director-general Prasat Trastarntip insisted the HSS would still support village health volunteers. "The changes are designed to improve our work," he said.