Arthropod-borne diseases

The treatment of Semliki Forest, San Angelo, and benzi viruses in mice suggests 7-thia-8-oxoguanosine (59) may be useful in treating arthropod-borne diseases that are endemic to Asia, the Pacific, and Africa. 

I. Kurane, in Anthology VI Arthropod Borne Diseases, J. Y. Richmond (Ed.), American Biological Safety Association, Illinois, 2003, 63-71. 

In the early 1940s, workers isolated WEE virus from Culex tarsalis mosquitoes25 and demonstrated the presence of specific antibody to WEE virus in birds,26 suggesting that birds are the reservoirs of the virus in nature. The annual incidence of disease in both equines and humans continues to vary widely, as would be expected of an arthropod-borne disease, and significant epidemics occurred in 1952, 1958, 1965, and 1975.24... 

Key Words Arthropod-borne disease quantitative real-time polymerase chain reaction vector-borne transmission vector competence. 

Since World War II, DDT has saved untold lives, not just from the scourge of typhus but from many other arthropod-borne diseases. According to a 1970 National Academy of Sciences report ... 

Arthropod-Borne Diseases Spread by Other Flying Insects.264... 

There have been several reviews concerning the safety of deet -" and they have attested to its generally acceptable safety profile in normal use, supporting the recommendation that it is the repellent of choice when visiting areas of endemic arthropod-borne diseases, particularly those transmitted by mosquitoes. 

There is a vast range of arboviral diseases transmitted by mosquitoes, and a few of those that are important to the travelers or in areas outside the tropics are presented in Table 13.4 along with a short discussion. Many of these also occur where other arthropod-borne diseases are present so that a repellent would usually be necessary. 

Whether marketing the product to avoid nuisance, hiting, and/or reduce the risk of arthropod-borne diseases... 

Flavivirus is a genus of the family Flaviviridae composed of nearly 70 arthropod-borne viruses that cause important human diseases, such as yellow fever virus (YFV), DENV, West Nile virus (WNV), and Japanese encephalitis virus (JEV). They cause a variety of diseases including fever, encephalitis, and hemorrhagic fever. In particular, DENV has reemerged in recent years as an increasingly important public health threat affecting more than 100 countries worldwide, with nearly 50 million infections each year and over 2.5 billion people at risk [81]. 

The virus was not, however, isolated until 1928, and a vaccine was first developed by the South African Max Theiler in 1939. Early attempts to eradicate the mosquito by physical means, and later through the use of insecticides like DDT, were only partially successful, and the disease is still endemic in much of West Africa and in South America, but not, surpisingly, in Asia. It has been suggested that this may be due to the fact that it closely resembles the virus that causes dengue fever, which is endemic in all of Asia. They are both arboviruses, which stands for arthropod-borne viruses, are both transmitted via the bite of a mosquito and cause a haemorrhagic illness. Survivors of dengue fever would be expected to have partial immunity (at least) to yellow fever. 

E. Vector-Borne Attacks Large number of infected live vectors can be produced to spread vector-borne diseases by releasing infected arthropod hosts such as mosquitoes, ticks or fleas. 

From 1945 to 1950 after World War II, Japan experienced very poor sanitary conditions due to the destruction caused by the war. Various kinds of infectious diseases were prevalent. In order to control the vector arthropods of insect-borne diseases, about 4 million Tokyo citizens were treated with DDT. Indeed, DDT saved the lives of many Japanese people after World War II. 

Military personnel deployed in the field often suffer more casualties due to endemic vector-borne disease than to engagement with enemy combatants. The most dangerous of these are carried (vectored) by biting arthropod vectors mostly of the bloodsucking variety. Among the diseases encountered by soldiers are malaria, dengue fever and yellow fever, carried by certain mosquito species encephalitis and Lyme disease, carried by certain ticks and leishmaniasis, carried by some species of sand flies (Fig 14.1). 

Hayes (5) has also reviewed the contribution of pesticides to the control of human diseases spread by arthropods and other vectors. Outbreaks of malaria, louse-borne typhus, plague, and urban yellow fever, four of the most important epidemic diseases of history, have been controlled by use of the organochlorine insecticides, especially DDT. In fact, the single most significant benefit from pesticides has been the protection from malaria. Today malaria eradication is an accomplished fact for 619 million people who live in areas once malarious. Where eradication has been achieved it has stood the test of time. An additional 334 million people live in areas where transmission of the parasite is no longer a major problem. Thus, about 1 billion people, or approximately one-fourth of the population of the world, no longer live under the threat of malaria. 

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