The experts believe that edible vaccines are possible in three to five years. Clinical trials on plant-derived edible vaccines are underway in some laboratories in the Philippines.
In a biotechnology research and regulation forum held last month, Dr. Nina Gloriani Barzaga, professor of medical microbiology and microbial immunology at UPM, said such vaccines are cost effective and reliable in production and delivery especially for developing countries like the Philippines. Compared with injectable vaccines, edible vaccines are easier, simpler, and cheaper to administer and are more acceptable to the public. She added that edible vaccines would elicit mucosal as well as systemic immunity or immunity of the entire body. This will help control transmission at the level where the pathogen enters the host and will provide systemic immunity.
A project of UPM focuses on Salmonella typhi, a bacillus found in human urine and feces responsible for causing typhoid fever. Experts say typhoid fever continues to be an endemic infection with incidence of recognized cases highest during rainy months. Multidrug-resistant cases have also been recognized for this disease.
This UPM project aims to produce transgenic bananas and/or tomatoes bearing Salmonella typhi genes encoding for flagellar antigen capable of stimulating an immune response. UPM is collaborating with UPLB’s Institute of Plant Breeding.
Other infectious agents such as enterotoxigenic Escherichia coli, Vibrio cholerae, and human immunodeficiency virus will also be studied for possible production of edible vaccines.
Edible vaccines are seen to be consumed in dried products or powder form placed in sachets for mixing with food or drinks. — Arlene R. Obmerga, S&T Media Service