What is Pandemic?
What is Pandemic?
Pandemic influenza is a worldwide outbreak of a new flu virus for which there is little or no immunity in the human population. Health experts including the Centers for Disease Control (CDC) and the World Health Organization (WHO) are concerned that the current virus in birds (avian flu) could develop into a human pandemic flu. A pandemic flu can create a public health emergency, with rapid spread between humans causing serious illness and death.
Have there been other Pandemics?
Influenza pandemics are not new to us: three have occurred in the last century. The worst of these, the 1918 pandemic, killed more than 50 million people worldwide. Most health experts agree that a future pandemic is inevitable.
Why is there so much concern over this now?
The heightened concern today results from the persistence of a highly pathogenic (disease-causing) strain of influenza, H5N1, which continues to infect large numbers of the bird population despite concerted efforts to contain and destroy infected birds. Though this influenza strain currently does not easily pass to humans, or to other mammals, there have been limited cases of such transmission. Also humans have no prior immunity to this strain and the few humans who have been infected suffered severe illness with a high death rate. Fortunately, human-to-human transmission of the virus is also limited at this time. However, the influenza virus has the capacity to gain enhanced transmission capabilities. If a new influenza strain gains the capability to pass readily between humans, the World Health Organization (WHO) estimates that, because of increased urbanization and globalization, mankind would have less than 12 weeks to respond, therefore preparedness for a pandemic is crucial.
What is needed for a Pandemic to occur?
Three conditions must be met for a pandemic to occur:
1. a new influenza virus subtype emerges,
2. the virus infects humans, and
3. the virus gains efficiency so that sustainable human-to-human transmission occurs.
Two of the three conditions have been met in regard to H5N1. The third condition can be met either through a mutation or a re-assortment in which the bird virus exchanges genetic material with a human virus during co-infection of a human or pig, thereby gaining the ability to be passed efficiently between humans.
How prepared are we for Pandemic and what works in slowing the spread of Pandemic Influenza?
For the first time in history, we have an opportunity to track the activity of a virus that has the potential to cause a pandemic and also to prepare for such an event. While many strategies are underway, including the development of anti-viral medicines and vaccines, most experts agree that we are currently inadequately prepared to respond to a pandemic.
If a new virus gains sustainable and efficient transmissibility, the public health strategy will focus on slowing the spread because it will be virtually impossible to stop it. Slowing the spread of disease will allow for better allocation and a more balanced use of limited resources by flattening the surge of cases.