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What Is The Mosquito Repellent Ingredient Known As DEET? And How Should It Be Applied To Skin?

What Is The Mosquito Repellent Ingredient Known As DEET? And How Should It Be Applied To Skin?

Many mosquito species found in urban and suburban areas throughout the US transmit disease to humans, and the most commonly transmitted mosquito-borne diseases in the country vary by region. For example, the often deadly disease known as eastern equine encephalitis (EEE) is contracted from mosquitoes in the northeastern coastal states, particularly Massachusetts, and during the Zika virus scare, residents of Florida and other Gulf Coast states were at the highest risk of contracting the virus.

Historically, mosquito-borne disease has not posed a significant threat to residents of Arizona, but mosquitoes that carry the west Nile virus recently established a permanent habitat in the state. In fact, during 2019, Arizona saw more West Nile infection cases than any other state in the country, and during 2019, at least 16 individuals in Arizona died from the disease. Now that mosquito-borne disease is a serious threat in Arizona, it is important for residents to take measures to prevent mosquito bites. It has become common knowledge that insect repellents containing the ingredient known as DEET are more effective at preventing mosquito bites than other non-DEET repellent products, but few people know what DEET actually is beyond this often repeated information.

N, N-diethyl-m-toluamide, or DEET, is the active ingredient in many insect repellent products, but contrary to popular belief, DEET does not kill mosquitoes on contact, and it does not necessarily repel mosquitoes either. DEET impairs the sense of smell in mosquitoes, which deprives them of their ability to sense human breath and sweat odors. DEET repellents are likely to repel mosquitoes after they land directly on a patch of skin where repellent has been applied. DEET insect repellents should be applied to clothing and bare skin, and ingesting the chemical must be avoided, so repellent should never be sprayed directly onto the face; instead, DEET should be rubbed into facial skin with fingertips.

Do you use DEET insect repellent during the spring and summer?

 

 

 

 

 

 

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Researchers Map Areas Of Arizona Where West Nile-Carrying Mosquitoes Are Most Abundant In Order To Reduce Human Infection Rates

Researchers Map Areas Of Arizona Where West Nile-Carrying Mosquitoes Are Most Abundant In Order To Reduce Human Infection Rates

Historically, mosquitoes in southern Arizona have never posed a significant disease threat, but this year the state saw an unprecedented surge in the number of reported West Nile virus cases. During 2019 alone, more than 170 people in Arizona contracted the West Nile virus from mosquito bites, 17 of whom died as a result of the disease. This makes Arizona the state with the highest number of West Nile virus cases by far, and surprisingly, the majority of victims contracted the disease in urban and suburban areas of Maricopa County.

Due to this abrupt and disturbing disease trend, researchers at Northern Arizona University have been collecting mosquitoes from Maricopa County and other urban portions of southern Arizona in order to determine which areas in the state see the greatest number and highest density of West Nile-carrying mosquitoes. The researchers are also hoping to better understand how infected mosquitoes arrived in the state in such large numbers. Unfortunately, the West Nile virus is now said to be a permanent part of southern Arizona’s ecosystem, so there is little to no hope at all that disease-carrying mosquitoes will be eradicated from the state.

According to genetic analysis, many West Nile virus strains are being found in Mosquitoes originating from southeast Maricopa County. This explains why West Nile infection rates were particularly high in the southeast valley this year, but since area-wide mosquito fogging is not feasible in populated areas, researchers must pinpoint specific sites where West Nile-carrying mosquitoes breed. According to Crystal Hepp, an evolutionary biologist at NAU, many infected mosquitoes are emerging near the intersection of Loop 101 and Loop 202 in Tempe. This did not come as a surprise to researchers, as shallow pools of water are littered throughout this area due to backup from the Salt River.

The largely residential town of Gilbert was also found to be a major source of West Nile-carrying mosquitoes, and this may be due to the significant amount of lawn irrigation and water-filled objects often found in yards. These sources of standing water provide disease-carrying mosquitoes with their primary breeding source. Hepp stated that if these areas of shallow and stagnant water are not removed within 72 hours, they become dangerous sources of mosquito-borne disease.

Do you make a point to remove standing water from your yard in an effort to reduce the mosquito population?

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Everything You Need To Know About Disease-Carrying Mosquitoes In Urban And Residential Areas Of Arizona

Everything You Need To Know About Disease-Carrying Mosquitoes In Urban And Residential Areas Of Arizona

The United States has seen an unusually high number of mosquito-borne disease cases this year. The most commonly transmitted mosquito-borne diseases in the US this year include the West Nile virus, eastern equine encephalitis (EEE), and St. Louis encephalitis. Public health officials are also closely monitoring cases of dengue fever and chikungunya in the eastern and southwestern regions of the country as well. While the high amount of documented EEE cases is higher than ever in the northeast this year, the southwest is seeing the highest amount of West Nile cases in documented history.

Between January 1st and September 24th of this year, 543 people in 46 states contracted the West Nile virus from bites inflicted by infected mosquitoes, according to officials with the Centers for Disease Control and Prevention. Of these victims, 156 contracted the disease from Culex mosquito species in Arizona, making Arizona the state with the highest number of people who have contracted the West Nile virus this year. Arizona has also seen 16 West Nile-related fatalities this year, and Culex mosquitoes remain active well into the fall season in the state. This is an alarming statistic considering that Arizona normally sees only 20 or so West Nile cases per year.

According to experts, West Nile is a preventable disease, as the virus is spread by urban-dwelling Culex mosquito species that rely on stagnant water sources in residential yards and urban areas in order to breed. Removing standing water and containers from properties would not only dramatically reduce the number of disease-carrying mosquitoes in the urban environment, but it would also prevent large numbers of Culex mosquitoes from congregating on residential properties where they transmit diseases most frequently. In Arizona, both Culex tarsalis and Culex quinquefasciatus transmit the West Nile virus to humans, and these two species are more commonly known as the western encephalitis mosquito and the southern house mosquito, respectively.

The western encephalitis mosquito dwells in rural areas where they are not often encountered by humans, but the southern house mosquito dwells primarily in residential and urban areas where females lay their eggs on the surface of stagnant water that has collected in a variety of containers, such as beer cans, bottle caps, gutters, kiddie pools, children’s toys, flower pots, neglected swimming pools, open septic tanks, storm drains, and culverts. Since this species maintains a habitat within 1 to 5 miles from their breeding source, these dangerous mosquitoes are always present around homes, and they are most active around dawn and dusk.

Do you worry about contracting mosquito-borne disease when you spend time outdoors?

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Why Are Mosquitoes Infecting So Many People With The West Nile Virus In Arizona?

Authorities in the Phoenix metro area are asking residents to keep their properties free of standing water sources, and to keep themselves protected from mosquito bites while outdoors. The number of West Nile virus cases has skyrocketed this year in Arizona, and the mosquitoes that spread this disease are urban-dwelling species that rely on small sources of standing water on residential properties in order to breed. Rainwater that collects in flower pot saucers, flower beds, kiddie pools, children’s toys, solo cups, aluminum cans and many other objects that are commonly found in yards attract massive amounts of disease-causing mosquitoes into neighborhoods. These water sources have ultimately been fueling the ongoing West Nile epidemic in Arizona, and therefore, removing standing water from properties can dramatically reduce the annual rate of  West Nile infections and even save lives.

Last year, only eight cases of West Nile occurred in Arizona, two of which resulted in death. However, as of August 28th, 135 West Nile Cases and eight deaths have occurred in the state, making Arizona the state with the highest number of West Nile infection cases. Despite California’s significantly higher population and greater size in terms of area, that state has seen 57 West Nile cases so far this year, far fewer than in Arizona. Surprisingly, California is second to Arizona when it comes to the number of West Nile cases per state, so why has Arizona become the number one state in the nation for West Nile virus cases? According to Dr. Stefanie Schroeder, medical director for ASU Health Services, West Nile cases increase during and after the monsoon season, and the virus is spread by both birds and mosquitoes, but it is not yet known which of the two is responsible for the current epidemic. In other words, nobody knows exactly why Arizona leads the nation in West Nile infection cases this year, but keeping properties free of standing water sources will certainly reduce the rate at which these cases occur..

Do you have more mosquito bites this year than you did last year?