Development of a Live Attenuated Vaccine Against Salmonella Paratyphi
Research type
Research Study
Full title
Development of a Live Attenuated Vaccine Against Salmonella Paratyphi A
IRAS ID
249094
Contact name
Andrew Pollard
Contact email
Sponsor organisation
Research Governance, Ethics and Assurance (RGEA), University of Oxford
Eudract number
2021-003259-41
Duration of Study in the UK
3 years, 1 months, 28 days
Research summary
Salmonella Paratyphi A is one species of bacteria that cause a disease called enteric fever, principally in low- and middle-income countries. This disease is characterised by feeling unwell, high fevers, and general aches and pains. If severe or untreated it can result in complications, long-term carriage of the bacteria or even death. It is spread by the faeces of an infected person, typically via contaminated water or food. Most high-income countries have eradicated enteric fever due to improved access to clean water and sanitation; this would ultimately be the goal for the whole world. In the medium term however, vaccination may offer a cost-effective strategy to prevent disease.
Whilst there are effective vaccines to protect against Salmonella Typhi (bacteria in the same family that causes the same disease), there is no current licensed vaccine against Salmonella Paratyphi A. A live attenuated (weakened) strain of Salmonella Paratyphi A that does not cause disease has been developed as an oral vaccine. Research suggests that prior infection with Salmonella Paratyphi A may protect against further infection. The Oxford Vaccine Group has developed a controlled human infection model of Salmonella Paratyphi A whereby volunteers are given a specific dose of the bacteria and a proportion of these volunteers will go on to become unwell. All volunteers are monitored closely. They are treated if they become unwell, or 14 days after drinking the bacteria, whichever is sooner. Participants will be randomised to receive either two doses of the vaccine or a placebo before being given the bacteria to see if the vaccine provides protection from infection.
This model provides an important time- and cost-efficient opportunity to test the effectiveness of this vaccine in human volunteers and provide samples to explore which aspects of the immune system may be responsible for protection against infection.REC name
South Central - Berkshire Research Ethics Committee
REC reference
21/SC/0330
Date of REC Opinion
19 Nov 2021
REC opinion
Further Information Favourable Opinion