Every winter, it's the same story: the flu returns. But it's not exactly the same. The viruses circulating one year can differ from those of the previous year, forcing diagnostic systems and vaccines to constantly adapt.
Understanding why this happens is key to appreciating the importance of having up-to-date and reliable detection kits .
The influenza virus: an expert at mutating
The flu (influenza) virus belongs to a family of RNA viruses that, by nature, tend to mutate easily .
There are three main types that affect humans: influenza A, B, and C , although the first two are the most clinically relevant.
In the case of the influenza A virus , its genome is segmented and can exchange fragments with other viruses in a process called genetic reassortment .
This leads to two types of changes:
- Antigenic drift: small, gradual mutations that accumulate over time. They are responsible for seasonal outbreaks each year.
- Antigenic shift: major combinations between viruses of different species (e.g., human and avian), capable of generating new strains with pandemic potential.
What this means in the laboratory
These genetic variations modify the surface proteins of the virus —hemagglutinin (HA) and neuraminidase (NA)—, which are the main targets of diagnosis and vaccination.
Therefore, an influenza detection kit that worked perfectly one year can lose sensitivity or specificity if it is not updated according to the most recent circulating strains.
International organizations, such as the WHO , continuously monitor influenza viruses to identify which variants are predominant. This information is used by both vaccine manufacturers and developers of molecular or immunological kits to refine their products.
This is how influenza detection kits are adapted
Modern kits — especially those based on RT-qPCR — are designed to detect highly conserved regions of the viral genome.
However, manufacturers periodically review the sequences of circulating viruses to:
- Verify the compatibility of the primers and probes .
- Introduce new detection pairs if critical mutations arise.
- Ensure simultaneous detection of the most frequent subtypes (e.g., Influenza A H1N1, H3N2 and B Yamagata/Victoria).
This ensures that a positive result received by a laboratory remains equally reliable, even if the virus "changes its appearance".
In summary
The flu changes every year because its virus is a master of genetic adaptation . That 's why laboratories need kits that evolve at the same rate.
Investing in up-to-date diagnostic solutions isn't just about performance; it's about ensuring clinical accuracy and public safety . Discover our influenza kits from uStar Biotechnologies and contact our product specialists with any questions.
