There are 16 different hemagglutinins and nine different neuraminidases, and reassortment of these two antigens determines the influenza A virus subtype (e.g., H1N1 or H3N2). Embedded within the ...

Influenza A virus (IFVA) is a significant cause ... are commonly caused by three HA (H1, H2 and H3) and two NA (N1 and N2) subtypes. IFVA Detection in Clinical Laboratories Nucleic acid ...

The centre said that the city’s dominating flu virus strain had shifted from influenza A subtype H3 seen in the January to March period to subtype H1 recorded in the most recent cases.

as determined by a positive PCR test for influenza and a virus type and subtype consistent with those of the index patient. All household contacts were tested for influenza on or before day 5 ...

“The strain of the virus has shifted from influenza A subtype H3 to subtype H1,” she said. “We may have another round of infection that is expected to take a few weeks. But it is difficult ...

Six main hemagglutinin (HA) subtypes of bird flu viruses (H3, H5, H6, H7, H9, and H10) have infected people to cause acute respiratory illness. In March 2024, a clade 2.3.4.4b influenza A(H5N1 ...