Salmonella Typhimurium, Scanning electron micrograph of Salmonella Typhimurium invading a human epithelial cell.Credit: NIAID
A single dose trial of the typhoid conjugate vaccine (TCV) has proved safe and 84% effective in protecting against typhoid fever a randomized trial in 27,882 children aged 9 months to 12 years, a randomized trial in Malawi found.
The findings, in the New England Journal of Medicine, was part of the Typhoid Vaccine Acceleration Consortium (TyVAC)—a larger effort led by Center for Vaccine Development, the Oxford Vaccine Group at the University of Oxford and PATH.
Half the participants in the trial, between March 2018 and September 2019, received Bharat Biotech Typbar-TCV vaccine while the other half received Serum Institute of India’s Meningococcal capsular group A conjugate (Men A) vaccine. Trial follow-up lasted for up to 24 months. The number of serious adverse events was 50% higher in the Men A group than among the TCV recipients. TCV was effective in protecting children from typhoid for a long period of time.
“This helps pave the way for additional countries to introduce TCV, making it available to pre-school, and school children,” notes study lead, Melita Gordon, a professor of global health at the University of Liverpool, United Kingdom.
Henry Mwandumba, acting director at Malawi Welcome Trust Clinical Research Programme at Kamuzu University of Health Sciences noted that “the vaccine is a great tool not only to control typhoid disease itself, but also to combat the spread of antimicrobial resistance.”
Co-author and TyVAC Consortium chief investigator, Kathleen Neuzil, says “TCVs have potential to protect millions of children impacted by typhoid and I hope other countries will introduce the vaccine in their immunisation programmes.”
