However, antigenic shift generates novel lineages to which immunity is therefore often very poor across the population. Consequently, pandemics are nearly always a result of antigenic shift events.

Every now and then, the virus changes dramatically in a process called antigenic shift. When this occurs, people become even less immune, and the likelihood of disease spread dramatically increases.

Antigenic shift causes an abrupt, major change resulting in new hemagglutinin and/or neuraminidase surface proteins. When antigenic shift happens, people often have little to no immunity.

Every now and then, the virus changes dramatically in a process called antigenic shift. When this occurs, people become even less immune, and the likelihood of disease spread dramatically increases.

This phenomenon is called antigenic drift, and can reduce the effectiveness of the flu vaccine for that season. An ongoing threat is that a major change in the flu virus, or antigenic shift ...

What you need to know about 'original antigenic sin' with fall COVID boosters around the corner. Experts are split on the role this will play in the fight against COVID.

Another change -- called antigenic shift -- occurs only occasionally. When it does occur, large numbers of people, and sometimes the entire population, have no antibody protection against the virus.

The challenge: any universal influenza A vaccine has to successfully account for both antigenic drift and antigenic shift. So far, this has proven very difficult.

Every now and then, the virus changes dramatically in a process called antigenic shift. When this occurs, people become even less immune, and the likelihood of disease spread dramatically increases.