Wednesday, October 19, 2005

FEAR THE FLU

FEAR THE FLU

Some where in a nameless village of Vietnam, a girl dies off and suddenly there is world wide alarms, similar deaths being accounted, scientists settle down full fledged in research trying to crack down the traffic of diseases between man and animals. Why - Because, the girl died of flu.

How Deadly?
While one in every ten just shrug off the disease, we should believe that about 30 to 60 million Americans catch it every year and some 36 thousand die. The flu virus mutates so fast that no one ever becomes fully immune and new medicines need to be produced every year. Chickens died within hours of exposure swollen and haemorrhaging. It killed lab mice, tigers and worst humans too with the same effect. In 1918, the last year of the First World War, large number of soldiers began to die at the tents, not due to the war but due to flu. In hospitals, youth were admitted for piercing headache and joint pains. They died off with faces turned purple as they essentially suffocated to death. When their lungs were cut open, it looked far different from the usual light and elastic sac, they looked like water logged sponges – filled with body fluid. Some 50 to 100 million died all around the globe.

Now
Today, scientists from all around the world fear of another such catastrophe. But this time, it could be even worse claiming 180 to 360 million lives. They say, “Sooner of later as deadly a virus that can jump from birds to people will sweep the globe”. And this virus is H5N1.

From the labs
While John Oxford tries his best with the paraffin embedded samples of lung tissues of victims died in 1918 pandemic, Yi Guan of Hong Kong University is tracking down the evolution of H5N1 bird flu virus.There are two types of flu virus, one is avian flu – attacks birds but lacks the capacity to spread fast in humans. Another is human flu – attacks humans and is extremely fast in transmission. Yet human body is capable of getting immune to it. Flu viruses carry their genetic material in 8 RNA segments. It becomes easy for its subtypes to swap genes if they meet through a process similar to a sexual intercourse. This causes mutation resulting in a newer flu virus. This is why we could not consummate with one medicine for flu while human body could not acquire complete immunity.
For human flu and avian flu (bird flu) to mix up, they should infect the same animal. The suspect is pigs for they can get human flu from the farmer and avian flu from the birds (especially ducks) of the same farm. Thus in 1957 and 1968 pandemics, human and avian flu viruses mixed yielding a hybrid which killed 2 million people around the globe. Strangely though, in 1918 something different happened. The flu virus was not a hybrid; its genetic pattern resembles very much that of an avian flu virus without a single sharing of human viral genes. Today H5N1 is doing the same thing. Scientists fearfully believe the present plight where H5N1 virus causes deaths only in tens instead of tens of millions is only tentative.

Anatomy of H5N1
May 1997 was the first time when H5N1 jumped to humans. Then again 17 deaths were reported in the same year in Hong Kong. Interestingly most of them who died were either frequently visiting or working in poultry farms. This event sent fears chilling in the veins of HK government. Hong Kong mass slaughtered 1.5 million birds in a measure to eradicate the deadly H5N1 virus. Regretfully, their belief turned out to be complacent. Again in 2001, another strain of H5N1 cropped up – once again a mass slaughter. Despite these desperate measures, the battle against bird flu turned out futile. In 2002 there was another outbreak, more severe this time. Only then it was found, the real source was from the mainland of China. H5N1 swapped its genes with other avian flu viruses producing a plethora of new variants. By the end of 2003, H5N1 reached South Korea and Japan in the north and up to Indonesia in the south originating in China. Governments evaded using migratory birds as the scape-goat explaining that birds have no boundaries. But researchers believe migratory birds could not be the source of spread as they would eventually die down if infected and cannot carry it long. The only mode being sophisticated shipments transporting live poultry – one of mankind’s marvels, now bitterly betraying.

The war
40 in Vietnam, 12 in Thailand, 4 in Cambodia have died of H5N1 flu so far. 40 million birds have died either out of disease or out of control measures on the whole causing a gross loss of 10 billion dollars in the year of 2004. The real scare in H5N1 is that so much of it including how it kills people is still unknown. With raising number of cases, even human to human transmission (which so far believed what avian flu is not capable of) is being suspected. Researchers from everywhere around the globe congressed and resolved not to wait for the invisible prank to show up. Now scientists of CDC (Center for Disease Control) Netherlands are artificially mixing and matching H5N1 with existing human flu virus to test the hybrids whether if any were a potential enemy.

In Hong Kong, a rich country could mass slaughter twice and disinfect the poultry frequently keeping the virus out of bounds.But in Vietnam, a poorer neighbor, mass slaughter only left the spread unabated. The Vietnam government suffers due to inefficiency, poverty and tradition to bring things under control.In Thailand a comparatively richer nation, slaughters only the infected poultry. But there duck herders traditionally drive flocks from field to field to eat the leftover rice - a practice that can efficiently spread the disease. In addition, with Laos, Cambodia as its neighbors any measure remains futile.

Will we win?
Analyzing statistically like an epidemiologist,
In 1918 pandemic caused by Human & pig flu claiming 50 to 100 million
In 1957 pandemic caused by Human & avian hybrid claiming 1 million
In 1968 pandemic caused by Human & avian hybrid claiming 0.75 milion
In 2005 pandemic caused by H5N1 (expected) claiming 180 to 360 million

With humans leaping distances faster with newer technologies, so does flu. In 1968 it took a year to spread around the earth, now it would take only as much as half the time. It is calculated that, even with a vaccine ready at hand, only at the 100th day of outbreak it could be distributed. But as of now (with no vaccine), a vaccine would be invented only on the 250th day. When could we distribute it?

Assuming somebody somewhere in a village gets infected and sparks an outbreak; Public Health Officials would be able to flood antiviral drugs treating hundreds of thousands of patients, if only the virus spreads too slowly in the beginning. But the sickening truth is, Asia lacks much of the necessary infrastructure.If, as it may seem, Asia fails in controlling flu, the whole world would get infected in less than a few months. Richer countries prepare Tami flu (a medicine believed to protect against H5N1). UK prepares it for curing 15 million (a quarter of its population), France almost for its entire population. But USA believes in a vaccine hence produces only for 2.3 million against its strength of 300 million.

But no one knows if H5N1 is the real threat or just a gimmick. Several other flu viruses have infected recently but nothing is as deadly as H5N1. Researchers at CDC Netherlands performing genetic analysis say the virus could either mutate into a virulent form or into an innocuous one.
Let’s keep our fingers crossed.

Bibliography : National Geographic, October 2005.
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