Mosquitoes West Nile virus

In the United States in recent years several diseases with animal hosts are now infecting humans. The Arena virus has as its host certain desert rodents. Rodent droppings when dry and airborne as dust particles infect humans, often with lethal consequences. The West Nile virus appeared in the United States in 1999. Birds carry this virus, and mosquitoes are the vector to humans. In 1999 the virus was localized in the New York City area. By 2000 it has spread across New York State and into New Jersey and Massachusetts. The West Nile virus is especially lethal when it infects children, the elderly, or those with a compromised immune system. 

The threat of West Nile virus has led government agencies to recommend the use of DEET repellents. West Nile virus is a mosquito-borne infectious disease that is common in Africa, west Asia, and the Middle East it was first detected in North America in 1999. 

Based on the previous work of this group on the three-component aza[4+2]/ allylboration strategy to construct polysubstituted piperidines [62], Gao and Hall developed a catalytic enantioselective version [63] of the corresponding oxygeneous process to construct a-hydroxyalkylated pyrans from 3-boronoacrolein [64], This recent variant of a Vaultier-Lallemand one-pot three-component reaction (see Scheme 12.14) was successfully applied to a concise total synthesis of (5R,6S)-6-acetoxy-5-hexadecanolide 128 (Scheme 12.20), the oviposition attractant pheromone of the female Culex mosquito [65] capable of transmitting the West Nile virus. 

West Nile fever is caused by infection with the fla-vivirus West Nile virus (WNV). The mosquito is the vector of transmission, specifically the Culex, Aedes, and... 

Mansonia mosquitos as well as some ticks, with birds as intermediate hosts (see Table 23.7—Clinical Profile of West Nile Fever). Historically, WNV was endemic to Africa, West Asia, and the Middle East. Scientists from the CDC believe the virus migrated to the eastern United States in the summer of 1999 or possibly earlier. The continued expansion of the virus in the United States indicates that it is permanently established in the Western Hemisphere (refer to Figure 23.7—2005 West Nile virus activity in the United States.). In the temperate zones, cases occur primarily in the late summer or early fall, whereas in the southern climates the virus can be transmitted year round (CDC, 2005e). Birds, mosquitoes, and equines serve as sentinel animals that could alert health officials to the occurrence of human disease. 

Anderson IF, Andr eadis TG, Vissbrinck CR (1999) Isolation of West Nile virus from mosquitoes, crows, and a Cooper s hawk in Connecticut. Science 286 2331—2333. 

Another insect that is commonly used in the evaluation of the biocidal activities of triorganotins is the mosquito. Mosquitoes are one of the most important blood-sucking arthropods in the world. They are not only annoying, but are responsible for the transmission of various diseases. For example, certain species of Aedes mosquitoes are responsible for the transmission of yellow fever, dengue, and other pathogenic viruses, while mosquitoes in the genus Anopheles are vectors of malaria. A third group is the Culex mosquitoes, which are important in the transmission of West Nile virus. 

Culex Another species of mosquitoes is the Culex p p ens, which is the northern house mosquito, and is the most common species found in urban areas. It is responsible for the transmission of West Nile Virus. 

Historically, the four most important arboviral pathogens in the United States were the St. Louis virus, the La Crosse virus, and the eastern and western equine viruses. However, the West Nile virus has been recognized as an emerging pathogen and has been implicated in an epidemic occurring in the United States since 1999. Transmission of these viruses occurs through the bites of mosquitoes. Typically, an incubation period of 2 to 14 days precedes the onset of clinical... 

Mosquito-bome members of the genus Flavivims in the family Flaviviridae provide some of the most important examples of emerging diseases, as well as one of the earliest documented disease that spread into a new geographic area Yellow fever virus (YFV) from West Africa into the Americas from the seventeenth century. More recently, the enormous resurgence of DENY in the tropical and subtropical areas of the world, the emergence of West Nile virus (WNV) in North America and the spread of Japanese encephalitis virus (JEV) through much of Asia and into Oceania have been recorded (Mukhopadhyay et al. 2005 Mackenzie et al. 2004). 

Lanciotti RS, Kerst AJ, Nasci RS, et al. Rapid detection of West Nile virus from human clinical specimens, field-collected mosquitoes, and avian samples by a TaqMan reverse transcriptase PCR assay. J Clin Microbiol. 2000 38 4066-4071. 

West Nile) lack characteristic inclusions. West Nile virus is an arbovirus. With mosquito and bird vectors and hosts, it has caused human infection. Its transmission by blood transfusion and organ transplantation has been documented. Some cases are fatal. 

By warding off biting insects, DEET protects against the diseases they carry. Mosquitoes, for example, carry diseases such as malaria, one of the most serious diseases in the world, responsible for an estimated three millions deaths a year encephalitis, an infection that causes inflammation and swelling of the brain and West Nile virus, an organism that affects the central nervous system and poses a serious threat to both humans and other animals. Ticks carry Lyme disease, an infection spread hy the deer tick that causes a skin rash, joint pain, and flu-like symptoms that can develop into a debilitating and permanent health problem if not treated early. 

OPs and CMs arc the most commonly used pesticides throughout the world. This is partly due to their lack of residue persistence in the environment and in exposed individuals and also due to lesser resistance development in insects compared to the orgaiiochlorine pesticides. From the public health standpoint, in today s world the use of pesticides is a mu.st rather than an option. For example, sporadic incidence.s of West Nile virus are reported in many countries, whereas malaria is still a major problem in developing countries. In both cases, the common vector is the mosquito. Without the use of pesticides against vectors of diseases, the impact on human and animal health would be devastating and the economic loss would be enormous. On the one hand, the world is greatly benefited from the use of... 

Most of the U,S, population has been exposed to organophosphorus (OP) pesticides in their homes, workplaces, outdoors, or through trace contaminants in food (Barr et al 2004 Casida and Quistad, 2004). OPs are used most heavily in agriculture. They are also used in the urban setting, for example, to protect home foundations from termites and to prevent the spread of West Nile virus carried by mosquitoes. OPs for use in the home and garden can be purchased at hardware stores. 

The pathogenic members of the flavivirus family, for example. West Nile virus and the closely related dengue virus, are transmitted by mosquito bites. Although an... 

Vector Competence of Japanese Mosquitoes for Dengue and West Nile Viruses... 

Possible Vector of Japanese Mosquitoes Against West Nile Virus 1221... 

All the hve mosquito species were susceptible to WNV (Table 1). The West Nile virus genome was detected in orally-infected Cx. p. pallens. These infection rates were 43%, 12%, and 75%, at 20, 25, and 28 °C, respectively. One of four orally infected mosquitoes showed strong signals of WNV genome in the thorax and the legs. The head of the same positive mosquito was negative. As the RT-PCR... 

Table I. Possible Japanese Vector Mosquitoes Related to West Nile Virus Transmission.

Dengue Virus, West Nile Virus, Japanese Mosquito, Vector Control, Susceptibility, Transmission... 

Cetin, H., Yanikoglu, A., Cilek, J. E. 2011. Larvicidal activity of selected plant hydrodistillate extracts against the house mosquito, Culex pipiens, a West Nile virus vector. 108(4) 943-948. 

Mike Fink, an epidemiology specialist for the Arizona Department of Health Services, separates the Culex genus mosquito, the carrier of the West Nile virus, from other mosquitos caught in a traps placed in suspected areas throughout the state at the department s lab August 5, 2004 in Phoenix, Arizona. (Getty Images)... 

Insect bites and stings, as well as being painful and annoying, can be lethal. Mosquito bites, in particular, transmit malaria to humans, and it is estimated to cause approximately 3 million deaths every year worldwide. Mosquito bites can also infect people with other nasty illnesses, such as West Nile virus, various types of encephalitis, and dengue fever. Insect bites and stings can also cause allergic reactions in people which can sometimes be fatal. So a chemical spray which can ward off insects is a potentially life-saving invention. 

There is the occasional case of West Nile virus or encephalitis in the United States, but mosquito-related diseases are generally not a major cause of death in wealthy and temperate parts of the world. See Landes (1998), pp. 10-11. 

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