VISAKHAPATNAM: Visakhapatnam-based researcher Madhuri Vissapragada has developed an edible probiotic yogurt-based vaccine concept for COVID-19, aimed at offering a needle-free alternative to conventional injections.The idea took shape during her undergraduate years, when the pandemic brought questions about repeated vaccine doses, side effects, and the need for easier delivery methods. “We were working on the structure of the coronavirus, especially the spike protein.
Then we started thinking about whether a vaccine could be designed for multiple variants and whether it could be given without the side effects that many people experienced after injections such as swelling, fevers etc,” she recalled. That line of thought led her to explore an oral vaccine. The result was ‘YoVac’, an edible vaccine prototype developed using probiotic bacteria commonly found in yogurt. The concept involves introducing a gene coding for the spike protein’s receptor-binding domain into Lactobacillus. Laboratory studies demonstrated that this genetic material could transfer to other bacteria in the gut microbiome, potentially increasing antigen levels and triggering a stronger immune response.
The study also found that the modified Lactobacillus in YoVac continued to express the protein for one month when stored at 4 degree Celsius, suggesting that the prototype had shelf-life stability under the tested conditions. The findings were published in Biochemical and Biophysical Research Communications, a journal under Elsevier, and patent applications have been filed.
“The next step is clinical evaluation to determine how the human body responds to the protein delivered through Lactobacillus,” Madhuri noted. Preparations for clinical trials are currently underway under the guidance of Dr Ravi Kumar Yedidi, founder of The Centre for Advanced-Applied Biological Sciences & Entrepreneurship Lab at Andhra University. Madhuri’s academic journey reflects a gradual entry into research. After completing her intermediate education in BiPC, she pursued a B.Sc. in Botany, Zoology and Chemistry from Dr. Lankapalli Bullaya College.
It was during this time that she attended a seminar by Dr Yedidi and joined his lab as part of an internship, eventually continuing her research work there. She later completed her Master’s in Human Genetics from Andhra University in 2023.”I want my work to contribute to public health in a meaningful way,” she expressed, adding that her goal is to make scientific solutions more accessible to common people.