A single-shot vaccine under development at the University at Buffalo in the US could protect against flu, Covid-19 and respiratory syncytial virus (RSV) simultaneously.  

In a study published in Science Advances, the researchers found that their three-in-one vaccine triggered protective immunity against all three respiratory diseases in mice, ferrets and cotton rats. 

“The antibody responses were comparable to those produced by vaccines that target just a single virus, suggesting that combining the three vaccines into one shot did not weaken their effectiveness,” saidcorresponding author Jonathan Lovell, SUNY Empire Innovation Professor in the Department of Biomedical Engineering, a joint programme of UB’s School of Engineering and Applied Sciences and Jacobs School of Medicine and Biomedical Sciences. 

The so-called ‘tripledemic’ of the three respiratory infections was associated with approximately one million combined hospitalisations in the United States during the 2023-2024 virus season alone. 

The single-shot vaccine uses Lovell’s “CoPoP,” platform, which consists of tiny spherical nanoparticles made of cobalt and porphyrin with an outer shell of phospholipid. 

The platform works by attaching viral proteins to the nanoparticles via histidine tags – or his-tags. These short strings of amino acids have a natural affinity for metals, allowing them to form a strong bond with the cobalt ions in the nanoparticles. Once administered into the body through the vaccine, the viral proteins help train the immune system to recognise and defend against the viruses. 

For this study, Lovell’s team used CoPoP to package five viral proteins – three influenza proteins and proteins from SARS-CoV-2 and RSV – into a single vaccine. To make the vaccine more potent, they also added immune-boosting ingredients known as PHAD and QS-21 to the CoPoP platform. 

The team found no evidence of immune interference, but stress that additional studies are needed.