The membership of MHWUN is made up of workers classified as Para-Medical/Anciliary Medical staff engaged in: Medical and Health Care Delivery Institutions, Federal/States Ministries of Health, Teaching/Specialist Hospitals, Federal Medical Centres, General/Government Hospitals/Health Centres, Health Management Boards, Armed forces, Federal, States and Local Governments Health Institutions and parastatals; Veterinary/Animal Health Centres, Pest control Centres/Institutions; corporately owned medical/health institutions; Social Welfare agencies, and all establishments responsible for General Sanitation, refuse collection and disposal, Food and Drug Administration. The spectrum of MHWUN membership also includes Scientific Officers, in any Institution so established for the performance of Medical and Health/Environmental related services, except Medical Doctors, Pharmacists, Nurses and Midwives.

The expansive membership of MHWUN is divided into four generic cadres of: health technologists and officers; health technicians; health assistants and; health attendants. The four generic cadres of MHWUN members providing human and animal health services encompass: twenty seven (27) specific technologist/scientific officers’ cadres; thirty two (32) specific health technician cadres; and seventy seven (77) specific health assistant cadres.