Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Insect Repellents”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 199 records · Page 11Linked to original sources
PubMed1977

Distribution and fate of the insect repellent 14C-N, N-diethyl-m-toluamide in the animal body. II. Distribution and excretion after cutaneous application.

The tissue distribution of 14C-labelled N,N-diethyl-m-toluamide (DEET), a widely used mosquito repellent, was studied by means of whole-body autoradiography after cutaneous application to mice. The early picture was very similar to that previously observed after intravenous injection of the substance, with high concentration of radioactivity mainly in the lacrimal gland, liver, bile, intestinal contents, kidney, urine, and nasal mucosa. Urinary excretion in mice was highest early after application whereas in a human volunteer maximal excretion appeared only after several hours. In mice a low but significant excretion persisted throughout the observation time of one month, probably emanating from the considerable amount of radioactivity remaining in the smeared skin area, as observed both autoradiographically and by means of quantitative measurements.

Administration, Topical↗
PubMed1988

Insect repellent, N,N-diethyl-m-toluamide, effect on ammonia metabolism.

There appear to be at least three mechanisms for systemic reactions to diethyltoluamide. As with most substances, allergy is possible. The ingestion of large doses can produce seizures and coma by a direct action on the CNS. This occurs in experimental animals in which seizures and coma followed by death can be produced rapidly if sufficiently large doses are given. Finally, with smaller systemic doses as may occur with absorption during heavy topical use, there is also the possibility of a perturbation of ammonia metabolism. Diethyltoluamide may then pose a substantial hazard to individuals with defects in ammonia metabolism.

Ammonia↗
PubMed1995

Insect repellent formulations of N,N-diethyl-m-toluamide (deet) in a liposphere system: efficacy and skin uptake.

Novel formulations for a deet in liposphere microdispersion in the form of lotion were prepared from natural solid triglycerides and phospholipids dispersed in buffer solution. The formulations containing 6.5, 10, and 20% deet were effective as a repellent against the common aggressive biting mosquitoes, Aedes aegypti and Anopheles stephensi, for up to 6 h. The acute dermal absorption of the 10% loaded formulation was conducted in rabbits using 14C-labeled deet. 14C-labeled deet, 10% in alcohol solution or in liposphere microdispersion was applied to the intact rabbit skin under a porous nonirritating cover for 7 days. Plasma levels of radioactivity were determined for 24 h, and daily for a total of 7 days. The 14C-deet blood levels following intravenous bolus administration were also measured. The bioavailability of deet from 10% ethanol solution was 45%, whereas the bioavailability of deet from lipospheres was 16%, a 3-fold reduction in the amount of deet absorbed. Examination of the rabbits during the experiment and after necropsy showed no evidence of toxicity or irritation. The 10% deet-liposphere formulation was stable at room temperature for at least 1 year.

Aedes↗
PubMed2006

Mosquito repellents in frog skin.

The search for novel insect repellents has been driven by health concerns over established synthetic compounds such as diethyl-m-toluamide (DEET). Given the diversity of compounds known from frog skin and records of mosquito bite and ectoparasite infestation, the presence of mosquito repellents in frogs seemed plausible. We investigated frog skin secretions to confirm the existence of mosquito repellent properties. Litoria caerulea secretions were assessed for mosquito repellency by topical application on mice. The secretions provided protection against host-seeking Culex annulirostris mosquitoes. Olfactometer tests using aqueous washes of skin secretions from L. caerulea and four other frog species were conducted to determine whether volatile components were responsible for repellency. Volatiles from Litoria rubella and Uperoleia mjobergi secretions were repellent to C. annulirostris, albeit not as repellent as a DEET control. The demonstration of endogenous insect repellents in amphibians is novel, and demonstrates that many aspects of frog chemical ecology remain unexplored.

Animals↗
PubMed2005

Passive prophylaxis with permethrin-treated tents reduces mosquito bites among North American summer campers.

OBJECTIVE: Over 2 million adolescents participate in summer-camp experiences, placing themselves at risk for mosquito-borne illness. Insect repellent is recommended but often not used. It is unknown whether permethrin treatment of a location, such as a campsite, provides passive prophylaxis reducing mosquito bites among all persons in the immediate vicinity. METHODS: This randomized, double-blind controlled trial used 0.4% permethrin (2.5% permethrin diluted by 7 parts water) sprayed once onto the external surface of canvas tents at a Boy Scout summer camp. During a 9-week period, subjects (n = 545) completed nightly mosquito-bite and -landing counts for 5 minutes at dusk and recorded insect-repellent use within 2 hours of counting. Weekly mosquito sampling with CO2-baited Centers for Disease Control and Prevention traps occurred at study campsites. The primary outcome measure was the number of mosquito bites per 5 minutes. RESULTS: A total of 1614 person nights averaged 5.1 +/- 7.2 (+/- SD) mosquito bites per 5 minutes. The permethrin-treated campsites had decreased mosquito landings and bites (relative risk reduction [RRR] 44%; 95% CI 34% to 55%; P < .001) compared with controls. Insect repellent was used only 32% of nights, decreasing bites by 36% (RRR 36%; 95% CI 25% to 47%; P < .001). Permethrin was superior to insect repellent alone (RRR 20%; 95% CI 4% to 37%; P = .01). CONCLUSIONS: Permethrin treatment of tents is an effective, inexpensive public health measure to reduce mosquito bites. Permethrin is effective among all individuals in a camping setting and was more effective than topical insect repellent alone, which, although recommended, was inconsistently used.

Adolescent↗
PubMed2004

Comparative resistance of Anopheles albimanus and Aedes aegypti to N,N-diethyl-3-methylbenzamide (Deet) and 2-methylpiperidinyl-3-cyclohexen-1-carboxamide (AI3-37220) in laboratory human-volunteer repellent assays.

The insect repellents N,N-diethyl-3-methylbenzamide (Deet) and the racemate and 1S,2'S stereoisomer of 2-methylpiperidinyl-3-cyclohexene-1-carboxamide (AI3-37220) were tested against Anopheles albimanus Wiedemann and Aedes aegypti (L.) in laboratory human-volunteer assays. Estimated skin doses of Deet or racemic AI3-37220 required to reduce biting by 95% in Ae. aegypti were 2.3 and 3.5 x 10(-2) micromol/cm2 skin, respectively, whereas estimated doses for 95% bite reduction of An. albimanus in an approximately 40-yr-old laboratory colony established from El Salvador were 5 times higher at 12 x 10(-2) micromol Deet/cm2 skin and >20 x 10(-2) micromol/cm2 skin for AI3-37220. In tests with the 1S,2'S stereoisomer of AI3-37220, a newly established colony of An. albimanus from Belize bit less aggressively than El Salvador An. albimanus. However, the Belize-derived mosquitoes were as resistant as the old El Salvador colony to repellent effects of 1S,2'S stereoisomer of 2-methylpiperidinyl-3-cyclohexene-1-carboxamide. Earlier workers surmised that usual skin doses of Deet would offer only limited protection against An. albimanus in the field. Our findings support this speculation, but they also indicate that doses of Deet higher than those needed for protection against Ae. aegypti might offer reasonable protection against An. albimanus. Results indicate that neither racemate nor 1S,2'S stereoisomer of 2-methylpiperidinyl-3-cyclohexene-1-carboxamide offer as much protection as Deet against An. Albimanus, despite being highly effective against Ae. aegypti.

Aedes↗
PubMed1991

Efficacy assessment of Quwenling, a mosquito repellent from China.

Quwenling, an insect repellent product of China derived from extracts of the lemon eucalyptus plant (Eucalyptus maculata citriodon), was evaluated. Laboratory tests compared Quwenling with deet against Anopheles albimanus, An. quadrimaculatus, Aedes aegypti, Ae. albopictus and field tests with Ae. taeniorhynchus. Cloth treated with Quwenling at greater than 2x the dosage of deet was effective against 2 of 4 species tested (Ae. albopictus 29 days, An. quadrimaculatus 28 days). On the skin of volunteers at 2x the dosage of deet, the duration of protection for Quwenling was significantly less than deet with Ae. aegypti and Ae. taeniorhynchus, and was not significantly different with Ae. albopictus. Both repellents were ineffective against the anopheline species. As a topically applied mosquito repellent, Quwenling has a shorter duration of effectiveness than deet.

Aedes↗
PubMed2004

Risk perceptions regarding ticks and Lyme disease: a national survey.

BACKGROUND: Lyme disease (LD) is caused by the tickborne bacterium Borrelia burgdorferi and, in 2000, accounted for >90% of all reported cases of vectorborne illness in the United States. Aside from anecdotal and indirect evidence, little empirical evidence exists regarding what the U.S. public knows, says, or does about preventing LD. OBJECTIVES: To examine knowledge, perceptions, and practices regarding prevention of tick bites and LD. METHODS: In 1998, a random-digit-dial frame was used to collect a cross-sectional sample (n =1500) from the 48 coterminous states plus the District of Columbia, and an over-sample (n =250) from six states with the highest incidence of LD. RESULTS: Forty percent of respondents reported doing something to avoid being bitten by ticks. Less than half (41%) used insect repellent. Ninety-two percent of those who had heard about LD stated their likelihood of ever getting the disease was </=50 on a 100-point scale (mean=29; standard deviation, 23.5). Being somewhat to very concerned about being bitten by ticks was strongly associated with taking preventive measures (odds ratio, 8.34; 95% confidence interval, 6.29-11.06). CONCLUSIONS: Having seen ticks, being concerned about being bitten, perceiving insect repellent to be effective, having heard about LD, and knowing someone who had LD are the factors most predictive of specific tick-bite preventive behaviors (p <0.001). However, greater efforts are needed in promoting the effectiveness and safety of DEET-containing insect repellents.

Animals↗
PubMed2003

Pre-West Nile virus outbreak: perceptions and practices to prevent mosquito bites and viral encephalitis in the United States.

Mosquitoes can transmit over 100 of the viruses that can cause encephalitis, meningitis, and hemorrhagic disease in humans (Chin 2000; Gubler 1996; Monath 1989). While much is known about the ecology, epidemiology, and clinical manifestations of the arboviral encephalitides (Campbell et al. 2002; Centers for Disease Control and Prevention 1997; Gubler 1998; Hayes 1989; Hubálek and Halouzka 1999), little empirical research exists regarding the U.S. population's knowledge of mosquitoes and arboviral encephalitis, particularly prior to the U.S. outbreak of West Nile virus (WNV) in 1999. A nationally representative 55-item survey instrument was successfully administered to 1,500 adults in the United States and an additional 250 adults in six states in the Northeast (Connecticut, Delaware, New Jersey, New York, Pennsylvania, and Rhode Island) regarding mosquitoes and mosquito-borne viral encephalitis. A summary outcome measure for mosquito bite prevention was created. Analyses revealed that the following were statistically significant predictors of behaviors taken to prevent mosquito bites: being concerned about being bitten by mosquitoes, perceived effectiveness of staying indoors in late afternoon and early evening was protective, perceived effectiveness that mosquito repellent is not harmful to health, owning dogs and/or cats as pets, being married, and being > or = 18-44 years old. Being concerned about being bitten by mosquitoes was the most robust predictor of behavioral action to prevent mosquito bites (OR = 7.3; 95% CI = 4.3, 12.2). Observed misperceptions and inadequate knowledge regarding insect repellents suggest increased promotion of the safety and efficacy of DEET-containing insect repellents is warranted.

Adult↗
PubMed1995

The present safety assessment of deet.

Deet is considered to be the best "all around" insect repellent ever developed and is the most widely used insect repellent in the world. Since its first use in a consumer product in 1956, billions of applications have been made to human skin. Information about the safety of deet comes from the human clinical literature, animal toxicology studies, and poison control centers' experiences with deet. The clinical literature reports the association of deet with neurotoxicity in 14 individuals. Three of the cases resulted in death, whereas all of the other patients completely recovered. The exact role of deet in the toxicity reported is difficult to determine from the reports. Recently reported animal safety studies have examined potential neurotoxicity following multigenerational dosing. Effects on the nervous system were only seen when generalized toxicity was also observed. Thus deet is not a selective neurotoxin. Important information about deet also comes from an investigation into the reports of adverse affects reported to 71 poison control centers in the USA. An important conclusion from this study is that there is no evidence that increasing deet concentration has any effect on the severity of the symptoms reported. The vast majority of reported cases had either no symptoms or ones that resolved rapidly. In conclusion, a thorough examination of all information available indicates that the risk of serious adverse effects following the use of deet is extremely low.

Animals↗
PubMed2003

DEET: a review and update of safety and risk in the general population.

The emergence of West Nile Virus (WNV) in North America has resulted in increased public awareness and utilization of insect repellents containing N,N-diethyl-m-toluamide (DEET) in the prevention of mosquito-borne disease. Regulatory reassessments in North American countries have recently been completed for insect repellents containing DEET as active ingredient, resulting in labeling changes intended to minimize unnecessary exposure to special populations, including children. This article describes those changes, and summarizes more recent data relating to the pharmacokinetics, toxicology, and epidemiology of adverse effects associated with DEET in humans.

Animals↗
PubMed1987

The relative efficacy of repellents against mosquito vectors of disease.

Laboratory tests of insect repellents by various different methods showed that An.stephensi Liston was consistently more susceptible than An.gambiae Giles, An.albimanus Wiedemann or An.pulcherrimus Theobald. The six repellents tested were di-ethyl toluamide (deet), di-methyl phthalate (DMP), ethyl-hexanediol, permethrin, citronella and cedarwood oil. Testing systems in which the mosquitoes were presented with a choice gave consistently lower ED50 values than when there was no choice, i.e. the standards of tolerance are not absolute but depend on the options available. In field tests in an experimental hut a curtain with a high dose of di-ethyl toluamide (deet) reduced biting in the hut but had to be re-impregnated frequently. Deet-impregnated anklets gave about 84% protection against Culex quinquefasciatus Say for 80 days after one impregnation, in a trial in which the anklets were brought out of sealed storage and tested for 2 h nightly. Similar protection was found against An.funestus Giles but the protection against An.gambiae s.l., An. coustani Laveran and Mansonia spp. was not as good. There were highly significant differences between the four collectors' mosquito attractiveness but this varied highly significantly between the mosquito species.

Animals↗