Further risks in the spread of the H5N1 virus were highlighted yesterday after it was confirmed that a domestic cat had died in Germany from the lethal virus. The cat which is believed to have come into contact with some swans was found dead on the Baltic island of Reugen at the weekend [BBC]. The development has prompted French ministers to warn pet owners not to allow their cats near areas where H5N1 had been reported [BBC]. But the jump to mammals, though rare, is only increasing the fear that a pandemic is closer than ever before. And the fear amongst consumers is also affecting the poultry trade. In the UK where there has yet to be any reported cases of the H5N1 virus in wild birds or amongst poultry, sales of chicken products has dropped sharply. One farmer in Essex said that his sales had dropped 70% from levels six months ago. “Because of scaremongering, media hype and the way things have gone…the whole industry has seen sales plummet,” said Ian Chisolm, a poultry farmer for eight years [Yellow Advertiser / BBC]. The facts are clear however. If the H5N1 virus should jump the species barrier to humans, the risk of a global pandemic is likely. Until then the spread of the virus amongst the global bird population will only increase the risk of that occurring. The annual flu (also called "seasonal flu" or "human flu") kills an estimated 36,000 people in the United States each year. The annual flu vaccine is made by combining vaccines for the new versions of H1N1 and H3N2 viruses that nature produces each year. The dominant strain of annual flu in January 2006 is H3N2. Measured resistance to the standard antiviral drugs amantadine and rimantadine in H3N2 has increased from 1% in 1994 to 12% in 2003 to 91% in 2005 "Contemporary human H3N2 influenza viruses are now endemic in pigs in southern China and can reassort with avian H5N1 viruses in this intermediate host." The Hong Kong Flu was a pandemic outbreak of influenza that began in Hong Kong in 1968 and spread to the United States of America that year. The outbreak ended the following year, in 1969.
The Hong Kong flu was the A type of influenza, specifically the first known outbreak of the H3N2 strain (a notation that refers to the configuration of the hemagglutinin and neuraminidase proteins in the virus).
Because of its similarity to the 1957 Asian Flu (which was the H2N2 strain, differing from the Hong Kong flu only in the chemical arrangement of the hemagglutinin protein as a result of antigenic shift) and possibly the subsequent accumulation of related antibodies in the affected population, the Hong Kong flu resulted in much fewer casualties than most pandemics. Casualty estimates vary: between 750,000 and two million people died of the virus worldwide (34,000 people in the United States) during the two years (1968-1969) that it was active. It was therefore the least lethal pandemic in the 20th century. The worst pandemic seen was after the Great War or WW I, and killed millions. The "Spanish flu", 1918-1919, first identified early March 1918 in US troops training at Camp Funstan, Kansas, by October 1918 it had spread to become a world-wide pandemic on all continents. Unusually deadly and virulent, it ended nearly as quickly as it began, vanishing completely within 18 months. In six months, 25 million were dead; some estimates put the total of those killed worldwide at over twice that number. An estimated 17 million died in India, 500,000 in the United States and 200,000 in the UK. The virus was recently reconstructed by scientists at the CDC studying remains preserved by the Alaskan permafrost. They identified it as a type of H1N1 virus. The future of the H5N1 virus is far from certain but the potential risk is very clear.
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