Ethnobotanical survey of medicinal plants used in treating viral infections among Yoruba tribe of South Western Nigeria

Ethnobotanical survey of plants used to treat some common viral diseases, such as chicken pox, poliomyelitis, influenza, hepatitis, measles and jaundice was carried out in Ekiti, Ondo, Osun and Oyo States in South Western Nigeria. Questionnaires were distributed among the participants and oral discussions were employed. Two hundred and eight (208) data were collected and tabulated. The Yoruba names, botanical names, methods of preparation and mode of administration of the plants were considered. The research work showed that members of the family Annonaceae (10.3%) were most frequently used, followed by members of Leguminosae (9.9%), and Zingiberaceae (7.9%), for treating chickenpox and measles infections, although all other plants play prominent roles in peoples' health care. Also, knowledge of medicinal herbs was being left in the hands of the elders between the age range of 51-70 years and 71-80 years. The leaves of the plants (45.5%) were mostly used in treating viral infections, followed by the use of stem bark (13.5%). All other parts were less commonly used to treat viral diseases. Mono-prescription was rare in the data collected. Oral application had the highest mode of administration (83.7%), while the combination of both oral and external applications (12.5%) closely followed. Decoction (90.4%) was the most frequently used method of anti-viral herbal preparation, while concoction (0.9%) was least used. Herb sellers (72.6%) constituted the major source of information about the use of anti-viral medicinal herbs, followed by traders, civil servants and herbalists with 17.31, 6.25 and 3.85 respectively. Many plants in the studied area may be a good source of lead molecules needed in viral chemotherapy after extraction of the bioactive components as well as removal of toxic residue following toxicological studies.