The University of Hong Kong and its affiliated centre, the InnoHK Centre for Virology, Vaccinology and Therapeutics, have developed a nasal spray vaccine against H5N1 avian influenza. The breakthrough comes as the world is still recovering from the COVID-19 pandemic, with scientists warning that new pandemics are inevitable.
The H5N1 virus has spread globally since its first detection in humans in Hong Kong in 1997 and is now considered a top candidate for triggering a human pandemic. Recent outbreaks in US dairy farms have led to dozens of human infections, raising concerns about the risk of further adaptation or recombination with seasonal flu.
A nasal spray vaccine offering single-dose protection could play a crucial role in outbreak control by rapidly inducing mucosal immunity at the primary site of viral entry. This approach is key to addressing the emerging H5N1 threat, as current vaccines often require multiple doses for efficacy and fail to curb viral transmission.
The Hong Kong team used an influenza virus vector-based nasal spray vaccine platform to develop the new vaccine. Animal studies have confirmed its high safety profile and ability to induce comprehensive immunity, including neutralizing antibodies and mucosal immunity in the upper respiratory tract. A single dose provides robust protection against infection and sustains immune memory, making it a critical reserve for future H5N1 outbreaks.
The research was funded by the InnoHK initiative of the Hong Kong government, with key contributors including Professor Chen Honglin and Professor Yuen Kwok Yung from the Centre for Virology, Vaccinology and Therapeutics. The findings were published in Nature Communications.
Source: https://www.eurekalert.org/news-releases/1079742