What Factors Can Cause an Influenza Pandemic?

The WHO pandemic warning is divided into six levels. "Level 3" means that a new subtype of influenza virus is causing human infection, but has not yet caused effective and continuous spread of human-to-human transmission; and "Level 4" means that a new virus can spread from person to person and can cause "group" outbreaks.

Flu pandemic warning levels

according to

WHO recommendations to national authorities during the influenza pandemic phase-phase 6:

(Regardless of disease activity)

Implement pandemic

WHO raises A (H1N1) flu warning to level 6

The World Health Organization announced at zero o'clock on the 12th to raise the alert level of the H1N1 influenza epidemic to the highest level of 6, indicating that WHO believes that the "flu pandemic" has arrived.

The World Health Organization announced in Geneva on the evening of April 29 that it has raised the global swine flu pandemic warning level from the current level 4 to level 5. The WHO swine flu pandemic warning is divided into 6 levels, and level 5 means that the same type of influenza virus has been transmitted from person to person in at least two countries in the same region, causing a sustained outbreak. This is the second time WHO has raised the pandemic warning level in three days after the swine flu epidemic began to spread. Announcing entry to Level 5 is a strong indication of an imminent pandemic, as Level 6 represents a pandemic outbreak worldwide.

At a telephone conference in Geneva on April 29, Assistant Director-General for Health, Safety and Environmental Affairs, Keita Fukuda said that there was no evidence of a slowdown in the spread of the swine flu epidemic and that the swine flu virus continues propagation.

The head of the World Health Organization s Global Alert and Response Division, Michael Ryan, said here on the 2nd that given that the current H1N1 flu epidemic is still concentrated in North America, the current global pandemic warning level remains at level 5, but with The number of confirmed cases in other regions is increasing, and the possibility of raising the warning level to 6 cannot be ruled out.

Speaking at a press conference at WHO headquarters, Ryan said that whether the warning level is raised depends mainly on the geographical scope of the virus's spread from person to person, not on the severity of the virus itself. If there is clear evidence that human-to-human H1N1 virus continues to spread beyond humans in North America, then it has the conditions to rise to a level 6 warning level. Europe is currently the most affected area outside North America, but there is no clear evidence of continued human-to-human transmission in this area. WHO will closely monitor the development of the virus in Europe.

The World Health Organization announces that the flu is no longer referred to as "swine flu" and is referred to as "HINI influenza A" (A (HINI) influenza)