H7N9 and Emerging Health Risks
4/3 如何預防H7N9？ (Photo credit: SimonQ錫濛譙)
Analysis by Dr. Don Donahue, Firestorm Expert Council Member
The emergence of a new strain, in this case H7N9, is continuing testimony to the enduring nature of influenza. The flu virus evolves rapidly, providing a challenge to the world-wide effort to limit its impact. Early identification is critical, as a vaccine must be developed for each strain – a process that takes 6-9 months.
This process is complicated by the need to verify the specific strain and potentially by political considerations within the nation in which the flu emerges. It is also exacerbated by the inexact science of predicting virulence.
The rapidly spreading 2009 H1N1 strain turned out to be milder than seasonal influenza. On the other hand, H5N1, which emerged in 2006, has been fatal to fully half of those infected. By comparison, the deadly 1918-9 influenza pandemic was fatal to 1-2 percent of those infected.
Exposure to emerging influenza viruses is particularly problematic in developing countries and regions. In these areas, the reservoirs – the source animals – often reside in very close proximity with humans. Exposure, therefore, exists as it would not in the industrial world. The danger is when the virus evolves to spread from human to human.
It is the role of global public health to monitor the emergence of novel viruses, including influenza, and to initiate countermeasures. At the local level, the pragmatic measures of cough etiquette, frequent hand washing, and staying home when ill will help reduce influenza spread.
See my earlier article from December 2012: Confirmed cases of Novel Coronavirus now Number 9