Developing oral vaccines for Food borne pathogens in poultry

Summary

We designed a Salmonella killed nanoparticle vaccine that can be delivered orally either through drinking water or feed.

Situation

Salmonellosis, a zoonotic disease caused by Salmonella enterica, has been estimated to cause 93.8 million infections (of which 80.3 million cases are food-borne) globally each year, with 155,000 deaths. In the United States, Salmonella infection is the most common food-borne illness reported (17.6 illnesses per 100,000 persons) and is associated with the largest number of hospitalizations and deaths. The major sources of human Salmonella infections are the contaminated meat and eggs from Salmonella carrier chickens. Vaccination programs are never 100 % successful because the current available vaccines are not efficient. The available live vaccines are not safe, and only reduce Salmonella colonization rather than eliminating it. Two kinds of vaccination practices are currently followed to control Salmonella in chickens. Broiler birds are typically sprayed on d 1 with live attenuated vaccines. FDA regulations prohibit the use of live Salmonella vaccines within 21 d of slaughter, and hence broiler birds are not typically vaccinated after the first d 1 inoculation. This practice typically leads to reduced or absence of anti-Salmonella antibodies by the time of slaughter, thereby enhancing the chances of Salmonella infection and contamination of broiler bird carcasses. Though Salmonella killed vaccines are available, they have to be injected either intramuscularly or subcutaneously, making the task impractical on large farms.

Response

We designed a killed vaccine that can be delivered orally either through drinking water or feed. A cheap affordable nanoparticle based Salmonella vaccine was developed in Dr. Selvaraj’s laboratory which can be delivered orally through drinking water and was shown to successfully decrease Salmonella load in chickens challenged with Salmonella. These antigen-loaded nanoparticles specifically deliver the vaccine antigen load to intestinal immune cells.

Impact

This project is the first of its kind to develop a safe and ideal nanoparticle-based Salmonella vaccine for oral delivery in chickens. The ultimate goal of Dr. Selvaraj’s research program is to improve the health and welfare of the poultry species which will result in a poultry product that will be free of food-borne pathogens and increase the profitability and sustainability of poultry production. Our nanoparticle platform can easily be modified to add additional vaccine antigens of not only Salmonella, but also other foodborne enteric pathogens. Success of this project will lead to developing innovative vaccine delivery platforms against other foodborne pathogens like Campylobacter and E. coli.

State Issue

Food Safety & Quality

Details

• Year: 2018
• Geographic Scope: National
• County: Clarke
• Program Areas:
  • Agriculture & Natural Resources