Since heat destroys the H5N1 virus, that causes bird flu, therefore Pakistan with moderate weather conditions and a relatively long span of summer, can be expected to effectively combat the threat.
Assistant Professor, Infectious Diseases Department at AKUH Dr Faisal Mehmood, in his presentation at PMA House here on Saturday said H5N1 remains overwhelmingly a disease of birds, and not humans.
The speaker mentioned that Avian viruses generally do not affect humans, but in 1997, an outbreak of bird flu in Hong Kong infected 18 people and also caused six deaths.
Since then, human cases of bird flu have been reported from different parts of the world including Asia and Europe. "Most were traced to be in contact with infected poultry or surfaces contaminated by sick birds," he said. The speaker mentioned that often, flu virus that cross the species barriers originate in areas where people live in close proximity to chickens. "That seems to be the case in most instances of human-acquired bird flu," Dr Faisal said.
The researcher also observed that outbreak of bird flu is no risk to the general public and can be controlled by culling. He, however, warned that available research does hint that the virus could mutate at some point in the future and trigger a lethal human flu pandemic.
Elaborating his stance, he said H5N1 mutates quickly and is able to incorporate large blocks of genetic code from viruses that infect other species, a process called re-assortment. For that reason, he said H5N1 has particular potential to combine with a human flu virus, creating a new viral strain that is feared to spread rapidly from person to person.
He stressed that under all conditions the most practical every day precaution effective at preventing a repeat of the dreadful bird flu history of the past could be effective hand hygiene. "Over 90 per cent of viruses like the bird flu enter our bodies through contact between the mucous membranes of the eyes and nose and the finger nails, " he said.
The speaker mentioned that although the exact incubation period for bird flu in humans is not clear, illness appeared to develop within one to five days of exposure to the virus. He agreed that people of all ages have contracted and died of bird flu in a scenario where very few people were infected to know all the possible risk factors for bird flu.
It was mentioned that people become sick after direct contact with infected birds or bird-contaminated surfaces, not from contact with other animals. To a question, he said no effective vaccine could be developed till bird flu virus mutates and that it would take several months to produce for a large population. There was said to be antiviral drugs, hospital facilities, intensive care and antibiotics.
The speaker stressed that improved public amenities like running water and improved hygiene may be the first and most practical line of defence against killer viruses like the bird flu. Answering a query, he said it has been established that infected migratory waterfowl, the natural carriers of bird flu viruses, shed the virus in their dropping, saliva and nasal secretions, which can spread among domesticated birds and domestic poultry become infected from contact with these birds or with contaminated water, feed or soil.