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Encephalitis warning in the USA
The battle to control mosquito-transmitted encephalitis has made national headlines. Less than 1 in 1000 mosquitoes carry the disease and most people who contact the virus do not develop symptoms. The virus causes an inflammation of the brain and produce headaches, stiff neck, fever and sometimes disorientation. Some patients lapse into a comma. The worst cases result in brain damage or death. (McGrath) Those at risk are small children, older people and those with weak immune systems. (Wilgoren)
The virus is believed to have arrived in southern New England each spring in the blood of migrating birds, which then pass it to mosquitoes. Now, a field study of songbirds has found evidence that the virus never dies here at all, but spends a comfortable winter inside the bodies of birds that live here year round. That would mean the virus isn t a chance visitor to the state, but a resident that makes an appearance every summer. (Woodside)
It is possible that the West Nile virus was transported here on jet plane from foreign climes most likely Africa or Asia through the blood of imported exotic birds or human travelers. Population upheavals are key factors in the spread of disease, and the fall of Communism and opening of borders this decade have led to one of the biggest global migrations ever. More than 100 million people have migrated to other countries since 1988. (Fritz) It is a vector-borne disease: To be transmitted to a human, it needs a go-between probably the common house mosquito. (Woodside)
Scientist do know that jet travel transports germs around the globe in hours, and a major port city such as New York, also home to many immigrant populations and frequent world travelers, is obvious landing spot. (Ferraro) The New York outbreak has led 37 confirmed or suspected cases, four deaths and concerns that migrating crows might spread an organism closely related to West Nile Virus. (McGrath)
While there are not records of people dying of the virus in Connecticut, In 1993, a 14-year-old boy attending camp on Block Island, RI died if it. Two years ago, a toddler of the virus he contracted in Springfield Mass also died of the virus. (Woodside) In Iowa, three cases of mosquito-transmitted encephalitis have been reported. It has been 12 years since there was proof that mosquito-transmitted encephalitis had infected anyone. (McGrath) In 1941, there were 250 reported cases in people and 1030 in horses. Since 1964, there have been only 41 people with laboratory-confirmed encephalitis. (McGrath)
Environmentalists think global warming could be a factor in this sudden spread. Cooler nights slow mosquitoes, and the first frost usually by mid-November will free us for the season. But none knows if the virus will return in the spring.(Ferraro)
So far there are reports of 732 dead birds, 180 in the city. Newark Malathion the chemical liberally sprayed over the city since September to kill mosquitoes probably doesn t hurt birds directly, but acute poisoning by it is possible if birds eat contaminated insects. (Ferraro)
Today s testing program is much larger than earlier efforts. In 1990, scientists examined about 7000 mosquitoes, and the next year, about 14,000. Last year they tested more than 66,000. It can be argued it can be argued that the virus always has been here and now is found only because so many mosquitoes are being tested. However, knowledge helps prevent outbreaks. In 1996 when the virus was found in 36 separate states, many of them of human-biting mosquitoes, the state ordered spraying of resmethrin, a pesticide that targets mosquitoes. No animals or people caught the virus that season. (Woodside)New Jersey adopted its program in 1914, largely to control malaria, the mosquito- borne disease that still kills more people globally than any other did.
The state opened a toll-free information hotline and it crashed within hours because of anxiety overload. Of the thousands of callers, the biggest number were concerned with the pesticide spraying, though folks worried about viral symptoms were a close second. (Fritz)
The encephalitis outbreak may very much have an impact on the kinds of activities we look in the future, since were obviously concerned about the problem now. It is not known how long the current siege of West Nile virus will last, exactly which insects are transmitting it from birds to humans, how virulent it is or even if global warming plays a role. (Ferraro) As a virus, it is extremely promiscuous, which means it has multiple hosts: people, different birds, different mosquitoes and ticks, said Dr. Dickson Despommier, a microbiologist at Columbia University. That makes it very complex biology. No one knows what will happen next. (Ferraro)
Bibliography
1. Ferraro, Susan. Ancient Disease is on Move More Questions that answers as Scientists battle encephalitis . Daily News. October 3, 1999
2. Fritz, Mark. Common Insect Holds key to uncommon disease . Los Angeles Times. October 2, 1999
3. McGrath, Mary. State s Mosquito transmitted A western Nebraska study finds encephalitis in Scotts Bluff Scotts Bluff Country colonies but no cases in humans or horses Viral Encephalitis. The Omaha World-Herald Company. October 5, 1999
4. Wilgoren, Jodi. New York Mosquito Control is Weak and late, Experts Say . The New York Times. September 8, 1999
5. Woodside, Christine. They re Here So is Fear of a Deadly Virus . The NewYork Times. June 13, 1999
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