Betainfluenzavirus

Betainfluenzavirus is a genus of viruses within the family Orthomyxoviridae. This genus contains influenza C viruses. These viruses are known to cause respiratory illness in humans. Influenza C viruses are distinct from influenza A and B viruses, which are responsible for more widespread and severe epidemics.

Betainfluenzaviruses are enveloped viruses with a segmented RNA genome. The genome consists of seven RNA segments, in contrast to the eight segments found in influenza A and B viruses. These segments encode for several viral proteins, including hemagglutinin-esterase (HE), nucleoprotein (NP), matrix protein 1 (M1), non-structural protein 1 (NS1), and a fusion protein (F). The HE glycoprotein is a unique surface protein found in betainfluenzaviruses and is thought to play a role in viral entry and release from host cells.

Infection with Betainfluenzavirus typically results in milder symptoms compared to influenza A and B infections. These symptoms can include fever, cough, sore throat, and runny nose. Severe illness and complications are less common, though they can occur, particularly in very young children and the elderly. Transmission occurs through respiratory droplets expelled when an infected person coughs or sneezes.

Diagnosis of Betainfluenzavirus infection is usually done through laboratory tests, such as RT-PCR, which can detect viral RNA in respiratory specimens. Antiviral medications approved for influenza A and B are generally not effective against Betainfluenzavirus. While there is no specific vaccine for influenza C, the milder nature of the illness means it is less of a public health concern than other influenza types.