When a pandemic flu occurs, the world can expect to be dealing with it for the next twelve to eighteen months.
Pandemics usually occur in waves. The first wave of illness may last from six to eight weeks. The second wave may follow six to nine months later. There may also be a third wave which will occur sometime within the twelve months following the second. Not all parts of the world, or every area of a country would be affected at the same time.
What is pandemic influenza? It is a new viral respiratory illness which is highly contagious and spreads quickly around the globe.
Influenza viruses are constantly mutating and producing different strains. When a new variety appears which can be transmitted from birds or animals to people, a pandemic is likely to occur rapidly, because humans have no immunity to it. The disease could cause widespread illness and death world-wide.
The virus is spread in droplets of liquid produced when an infected person coughs or sneezes. When the viruses come into contact with someone else's eyes, nose or mouth, they can enter the body and claim a new victim.
It can also be spread when an uninfected person touches an object or surface recently in contact with a patient, and he or she then touches their face.
Two to four days after exposure, the new victim will develop some or all of these symptoms: a sudden temperature rise to about 104 degrees Fahrenheit, which will persist for several days, chills, muscle aches and pains, sore throat, cough and shortness of breath. Vomiting, cramps and diarrhoea may also be present, especially in children.
A patient is contagious one day before his symptoms appear, six days afterward, and perhaps longer. Some people may recover without medical help; the elderly, young people, those with chronic illness or weakened immune systems should seek medical help when symptoms appear.
There will be no vaccine when the illness appears, because it is caused by a new virus, and vaccine production can take several months. Anti-viral drugs are effective, but they are likely to be in short supply, because demand will be great once a pandemic outbreak is announced.
For the last three hundred years, the world has averaged three pandemics per century. The most recent ones have been the Spanish flu, (1918), the Asian flu (1957) and the Hong Kong flu (1968). Experts believe we are overdue for the next one.