Influenza

Virus and disease overview

Some influenza viruses are responsible for seasonal epidemic outbreaks of influenza, a highly contagious respiratory disease. Seasonal influenza viruses are primarily divided into two main types: influenza A and influenza B.

Both types cause similar symptoms, including fever, cough, and body aches, and they spread easily from person to person. However, influenza A viruses are considered to be of greater concern because of their ability to infect a wider range of hosts, including birds, mammals and humans. This broader host range increases the potential for the emergence of a new, unpredictable strains that could lead to a new pandemic. In contrast, influenza B viruses circulate primarily among humans and are less likely to cause large-scale outbreaks.

Detection in Wastewater and Public Health Relevance

Infected people shed influenza virus particles in their stools, which can be detected in wastewater. Wastewater surveillance can enhance existing clinical surveillance systems by providing a more comprehensive picture of the influenza virus circulation throughout the year.