Dangerous Combination of Influenza A and Respiratory Syncytial Virus... Emergence of Hybrid Virus

"A Completely New Type of Viral Pathogen" ... Higher Infectivity Than Individual Viruses
Outbreak from Late Autumn to Winter ... Evades Immune System and Reaches a Wider Range of Lung Cells

[Image source=Yonhap News]

[Asia Economy Lee Gyehwa Intern Reporter] Amid concerns about a 'triple-demic' involving simultaneous infections of COVID-19, influenza, and respiratory syncytial virus (RSV), a study has revealed the possibility that a hybrid virus could be created when two types of viruses infect simultaneously.

On the 24th (local time), the University of Glasgow in the UK discovered a hybrid virus formed by the fusion of influenza A and RSV, and published the findings in the international journal Nature Microbiology. The hybrid virus was found to evade the human immune system and infect lung cells.

Both viruses are prevalent domestically from late autumn through winter. Influenza A became a seasonal disease after causing a global pandemic in 2009, infecting approximately 5 million people annually. RSV is a major cause of acute respiratory infections such as pneumonia and bronchiolitis in children under five years old and can cause severe illness in some children and the elderly.

Co-infection of a person with both viruses is relatively common, but it was unclear how these viruses would interact if found within the same cell.

The research team infected human lung cells with both viruses and observed the results. Instead of competing, the two viruses fused to form a palm tree-shaped hybrid virus.

The resulting hybrid virus had a greater ability to infect cells than the original viruses. Even when lung cells had antibodies against influenza A that would bind to the hybrid virus, it used RSV proteins to infect the lung cells.

Professor Pablo Murcia of the University of Glasgow said, "This type of hybrid virus has never been recorded before," adding, "We have discovered a completely new type of viral pathogen where the genomes and external proteins of two viruses combine."

The hybrid virus was able to evade the immune system and work together to access a broader range of lung cells. Influenza typically infects cells in the nose, throat, and bronchi, whereas RSV tends to prefer the bronchi and lung cells.

Virologist Professor Steven Griffin of the University of Leeds Medical School in the UK stated, "Further research is needed to prove that the hybrid virus affects human disease," and added, "RSV tends to penetrate deeper into the lungs than influenza A, so the longer the infection persists, the more likely it is to lead to severe illness." He also emphasized, "Because there is a possibility of hybrid viruses emerging, it is important to avoid infections by multiple viruses."