Ticks attaching to ear canals of humans and animals are the cause of otoacariasis, common in rural areas of Nepal. The plant Clerodendrum viscosum is used in multiple indigenous systems of medicine by ethnic communities in the Indo-Nepali-Malaysian region. Visiting the Chitwan National Park, we learned that in indigenous medicine, flower extract of C. viscosum is utilized to treat digestive disorders and extracts from leaves as tick repellent to prevent ticks from invading or to remove them from the ear canal. The objective of our study was to provide support to indigenous medicine by characterizing the in vivo effect of leave extracts on ticks under laboratory conditions and its phytochemical composition. We collected plant parts of C. viscosum (leaves and flowers) and mango (Mangifera indica) leaves at the Chitwan National Park, previously associated with repellent activity to characterize their effect on Ixodes ricinus ticks by in vivo bioassays. A Q-ToF high-resolution analysis (HPLC-ESI-QToF) was conducted to elucidate phenolic compounds with potential repellent activity. Clerodendrum viscosum and M. indica leaf extracts had the highest tick repellent efficacy (%E = 80-100%) with significant differences when compared to C. viscosum flowers extracts (%E = 20-60%) and phosphate-buffered saline. Phytochemicals with tick repellent function as caffeic acid, fumaric acid and p-coumaric acid glucoside were identified in C. viscosum leaf extracts by HPLC-ESI-QToF, but not in non-repellent flower extracts. These results support the Nepali indigenous medicine application of C. viscosum leaf extracts to repel ticks. Additional research is needed for the development of natural and green repellent formulations to reduce the risks associated with ticks resistant to acaricides.
- Keywords
- Clerodendrum, Nepal, Otoacariasis, Repellent, Tick,
- MeSH
- Acaricides * MeSH
- Clerodendrum * chemistry MeSH
- Ixodes * MeSH
- Humans MeSH
- Insect Repellents * pharmacology MeSH
- Plant Extracts pharmacology chemistry MeSH
- Animals MeSH
- Check Tag
- Humans MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Names of Substances
- Acaricides * MeSH
- Insect Repellents * MeSH
- Plant Extracts MeSH
In in vitro tests, skin repellent IR3535, applied in the form of the Diffusil H Prevental product in an aerosol bomb (active compound 20%), killed 100% of head lice (females and males) and nymphs 2 and 3, when directly sprayed at a dose of 0.94 mg of the active compound per square centimeter. Crawling lice exposed for 1 min on the filter paper impregnated by the same concentration showed no effort to suck blood 30 min after exposition. Twenty hours later, their mortality rate was 11 %. After the lice had been exposed for approximately 1 min (until they actively left the area) on 5 cm round areas of skin of test persons treated with the repellent at a mean total dose of 23.3 mg of active compound, they showed no effort to suck blood on the clean skin of other test person either immediately after exposure or 30 min later. Their mortality after 20 h ranged from 59 to 16%, depending on the time elapsed from skin treatment (10 min to 27 h).
- MeSH
- Nymph drug effects MeSH
- Phthiraptera drug effects MeSH
- Propionates pharmacology MeSH
- Insect Repellents pharmacology MeSH
- Feeding Behavior drug effects MeSH
- Animals MeSH
- Check Tag
- Male MeSH
- Female MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Names of Substances
- ethyl-3-(N-n-butyl-N-acetyl)aminopropionate MeSH Browser
- Propionates MeSH
- Insect Repellents MeSH
Insecticido-repellent mixtures sprayed on clothes, nets etc. are useful as a means of protection against attack by bloodsucking arthropods. These sprays provide repellence of insects sensitive to the repellent and kill those that are only weakly repellent sensitive. Combined formulae for aerosols including repellent DETA and the synthetic pyrethroid neopynamin ("Neorepellent-2") or sumithrin ("Sumirepellent") were proposed. The composite sprays were studied in an olfactometer fleas (X. cheopis) and under practical conditions by treating clothes with 7-15 g of mixture per 1 m2. The composite sprays gave 100% repellence for fleas and mosquitoes, 80-50% repellence for simuliids, 65-70% repellence for ceratopogonids and tabanids, 90-95% for ticks, and they killed 100% of insects having contacted treated surface. As regards Ixodes ticks, "Sumirepellent" was more effective than "Neorepellent-2" and caused irreversible paralysis. Toxicological tests showed the composite sprays to be safe in broad-scale practical use provided that measures of precaution were kept.
- MeSH
- Aerosols MeSH
- DEET adverse effects MeSH
- Insecticides * adverse effects MeSH
- Ticks MeSH
- Rabbits MeSH
- Phthalic Acids adverse effects MeSH
- Humans MeSH
- Pyrethrins adverse effects MeSH
- Insect Repellents * adverse effects MeSH
- Siphonaptera MeSH
- Animals MeSH
- Check Tag
- Rabbits MeSH
- Humans MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Names of Substances
- Aerosols MeSH
- DEET MeSH
- dimethyl 4-phthalate MeSH Browser
- Insecticides * MeSH
- Phthalic Acids MeSH
- phenothrin MeSH Browser
- Pyrethrins MeSH
- Insect Repellents * MeSH
- tetramethrin MeSH Browser
ETHNOPHARMACOLOGICAL RELEVANCE: The use of Hazomalania voyronii, popularly known as hazomalana, to repel mosquitoes and resist against insect attacks is handed down from generation to generation in Madagascar. In the present study, we investigated the ability of the essential oils (EOs) obtained from the stem wood, fresh and dry bark of H. voyronii to keep important mosquito vectors (Aedes aegypti and Culex quinquefasciatus) away, as well as their toxicity on three insect species of agricultural and public health importance (Cx. quinquefasciatus, Musca domestica and Spodoptera littoralis). MATERIALS AND METHODS: Hydrodistillation was used to obtain EOs from stem wood, fresh and dry bark. The chemical compositions were achieved by gas chromatography-mass spectrometry (GC-MS). Toxicity assays using stem wood and bark EOs were performed on larvae of Cx. quinquefasciatus and S. littoralis, and adults of M. domestica by WHO and topical application methods, respectively. Mosquito repellent activity of the most effective EO, i.e. the bark one, was determined on human volunteers by arm-in-cage tests, and results were compared with that of the commercial repellent N,N-ddiethyl-m-toluamide (DEET). RESULTS: The H. voyronii EOs were characterized by oxygenated monoterpenes with perilla aldehyde (30.9-47.9%) and 1,8-cineole (19.7-33.2%) as the main constituents. The fresh and dry bark EOs were the most active on Cx. quinquefasciatus and S. littoralis larvae, respectively, with LC50/LD50 of 65.5 mg L-1, and 50.5 μg larva-1; the EOs from wood and fresh bark displayed the highest toxicity on M. domestica (LD50 values 60.8 and 65.8 μg adult-1, respectively). Repellence assay revealed an almost complete protection (>80%) from both mosquito species for 30 min when pure fresh bark EO was applied on the volunteers' arm, while DEET 10% repelled >80% of the mosquitoes up to 120 min from application. CONCLUSION: The traditional use of the bark EO to repel insects has been demonstrated although an extended-release formulation based on H. voyronii EOs is needed to increase the repellent effect over time. A wide spectrum of insecticidal activity has been provided as well, suggesting a possible use of H. voyronii EOs in the fabrication of green repellents and insecticides useful to control mosquito vectors and agricultural pests.
- Keywords
- Aedes aegypti, Culex quinquefasciatus, Dengue, Insecticides, Mosquito repellent, Musca domestica, Spodoptera littoralis, Zika virus,
- MeSH
- Aedes drug effects growth & development MeSH
- Time Factors MeSH
- Culex drug effects embryology MeSH
- DEET pharmacology MeSH
- Wood * chemistry MeSH
- Hernandiaceae * chemistry MeSH
- Plant Bark * chemistry MeSH
- Larva drug effects growth & development MeSH
- Humans MeSH
- Mosquito Control * MeSH
- Houseflies drug effects growth & development MeSH
- Oils, Volatile isolation & purification pharmacology MeSH
- Plant Oils isolation & purification pharmacology MeSH
- Insect Repellents isolation & purification pharmacology MeSH
- Spodoptera drug effects embryology MeSH
- Animals MeSH
- Check Tag
- Humans MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Comparative Study MeSH
- Names of Substances
- DEET MeSH
- Oils, Volatile MeSH
- Plant Oils MeSH
- Insect Repellents MeSH
OBJECTIVES: In the Czech Republic, autochtonous transmission of mosquito borne diseases is not common; however, the need for personal protection should not be underestimated. Many people still rely on homemade repellents utilizing recipes based on local folk wisdom that are published annually in local Czech media. Despite minimal disease risk, nuisance biting and potential allergic responses make it essential to evaluate the chemical composition, effect, and duration of four homemade repellents often used and determine the necessity for public health education on application and use of alternative repellent products. METHODS: A review of local web-based media was conducted to identify the most commonly advertised homemade repellent products. The top four products were rosemary (Rosmarinus officinalis), sagebrush (Artemisia absinthium), walnut-tree (Juglans regia) leaves and clove (Syzygium aromaticum). These repellents were then prepared following the published recipes to evaluate their repellency effects, and reveal potential allergen presence. A bioassay against Aedes aegypti was conducted on ten volunteers for each repellent and the chemical composition was detected using gas chromatography. RESULTS: Significant initial repellency effect was found in mixtures of the clove (73.1%) and walnut leaves (49.0%) with ALPATM herbal embrocation after 10 minutes. The efficacy decreased to 46.5% and 34.3 % after 30 minutes, respectively; and, 30.3 and 18.2%, 60 minutes after the application. The remaining two samples, Rosmarinus officinalis and Artemisia absinthium solutions, exhibited no significant effects against Ae. aegypti. The evidence of allergens including cinnamic aldehyde, eugenol and coumarin were detected indicating potential concerns for product safety. CONCLUSION: The homemade repellents reviewed were either ineffective or had unstable repellency effect within one hour. The low efficacy of these products may be appropriate to decrease nuisance biting, but should not be considered for primary prevention against mosquito borne diseases in areas with active disease transmission. Additionally, more research is needed to assess rates of allergic responses to homemade repellent products.
- Keywords
- personal protection - insect repellent - efficacy test - allergen content, personal protection - insect repellent - efficacy test - allergen content.,
- MeSH
- Aedes * MeSH
- Laboratories MeSH
- Insect Repellents * standards MeSH
- Medicine, Traditional MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
- Geographicals
- Czech Republic MeSH
- Names of Substances
- Insect Repellents * MeSH
Wildlife-vehicle collisions (WVC) amount to 11% of all registered traffic crashes in the Czech Republic causing, apart from numerous deaths and serious injuries to animals, property damage and injuries to car passengers. Odor repellents have the potential to lower the overall number of WVC and allow animals to cross roads at the same time. We tested the effectiveness of odor repellent preparation in prevention of WVC. 18 places were selected on the Czech road network where WVC were concentrated on the basis of traffic crash data. Control sections on the same road segments were also delimited in order to keep the traffic intensities constant. We applied a Before-After-Control-Impact (BACI) study design to control not only the effect of the measures but also the expected natural variations in wildlife populations over time. Data were compared before and after odor repellent installations. Wildlife carcass gathering was carried out during the spring and autumn. We also used the police crash database to supplement carcass data when no field works were carried out. 201 killed mammals (roe deer and wild boars) were identified in total over 47 months. We applied a Bayesian approach as only a limited numbers of WVC were available. A WVC decrease between 26 - 43% can be expected on the treated road sections. These numbers are, however, up to three-times lower than those claimed by producers of odor preparations.
- Keywords
- Bayesian statistics, Before-After-Control-Impact study, Odor repellent,
- MeSH
- Bayes Theorem MeSH
- Behavior, Animal MeSH
- Animals, Wild * MeSH
- Accidents, Traffic prevention & control MeSH
- Odorants * MeSH
- Swine MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
- Geographicals
- Czech Republic MeSH
An experiment was carried out in South Bohemia, in which 10% water emulsion of diethyltoluamide was used as repellent against bloodsucking Diptera to protect pastured dairy cattle. The repellent was applied by means of a spraying frame and was effective for 30-36 hours. Seven mosquito species and 18 horsefly species were observed to be attacking the cattle. The average number being 120-300 mosquitoes and 50 horseflies per hour, the milking qualities in the cattle decreased by 6.2%, the milk fat content by 11.8%. After converting to milk with average fat content of 4%, the difference in milking qualities between treated and untreated animals was 9.7%.
- MeSH
- Aerosols MeSH
- Benzamides therapeutic use MeSH
- Culicidae * MeSH
- DEET therapeutic use MeSH
- Diptera * MeSH
- Species Specificity MeSH
- Insect Bites and Stings prevention & control veterinary MeSH
- Milk analysis MeSH
- Cattle Diseases metabolism prevention & control MeSH
- Insect Repellents * MeSH
- Cattle MeSH
- Fats analysis MeSH
- Animals MeSH
- Check Tag
- Cattle MeSH
- Female MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Names of Substances
- Aerosols MeSH
- Benzamides MeSH
- DEET MeSH
- Insect Repellents * MeSH
- Fats MeSH
The chemical defence of Heteroptera is primarily based on repellent secretions which signal the potential toxicity of the bug to its predators. We tested the aversive reactions of green lizards (Lacerta viridis) towards the major compounds of the defensive secretion of Graphosoma lineatum, specifically: (i) a mixture of three aldehydes: (E)-hex-2-enal, (E)-oct-2-enal, (E)-dec-2-enal; (ii) a mixture of these three aldehydes and tridecane; (iii) oxoaldehyde: (E)-4-oxohex-2-enal; (iv) secretion extracted from metathoracic scent glands of G. lineatum adults and (v) hexane as a non-polar solvent. All chemicals were presented on a palatable food (Tenebrio molitor larvae). The aversive reactions of the green lizards towards the mealworms were evaluated by observing the approach latencies, attack latencies and approach-attack intervals. The green lizards exhibited a strong aversive reaction to the mixture of three aldehydes. Tridecane reduced the aversive reaction to the aldehyde mixture. Oxoaldehyde caused the weakest, but still significant, aversive reaction. The secretion from whole metathoracic scent glands also clearly had an aversive effect on the green lizards. Moreover, when a living specimen of G. lineatum or Pyrrhocoris apterus (another aposematic red-and-black prey) was presented to the green lizards before the trials with the aldehyde mixture, the aversive effect of the mixture was enhanced. In conclusion, the mixture of three aldehydes had the strong aversive effect and could signal the potential toxicity of G. lineatum to the green lizards.
- Keywords
- Aposematism, Aversive reaction, Chemical defence, Graphosoma lineatum, Repellent secretion,
- MeSH
- Aldehydes isolation & purification pharmacology MeSH
- Heteroptera chemistry MeSH
- Lizards physiology MeSH
- Scent Glands chemistry MeSH
- Feeding Behavior drug effects MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Names of Substances
- Aldehydes MeSH
Blood-sucking dipterous insects, milk yield losses caused by these insects to cows in the pasture and the possibilities of cattle protection against these insects were investigated in the Leningrad region of the USSR in 1982-1984. The invasion by horse-flies causes the greatest trouble to grazing cattle. Twenty-five horse-fly species were identified during the study. The nine prevailing species constituted more than 85% of the horse-flies invading the animals. The horse-flies flew for 50-55 days from the beginning of June to the beginning of August; mass flights were observed for two weeks starting in the second decade of June. A twelve-hour repelling action was recorded in the Oxamate repellent applied as 20% emulsion. A new portable motor-powered aerosol sprayer was tested during the study. The losses in milk yields caused by horse-flies in the Leningrad region were computed; in the period of the horse-fly flights the milk yields are reduced by 13%. The economic benefit of the treatment of the animals with the Oxamate repellent was 9.11 roubles per rouble invested. Manitoba-type traps attracting the horse-flies to an optical bait (a black ball or cube) were used as an additional method of reducing the occurrence of horse-flies in the pasture.
- MeSH
- Diptera * MeSH
- Lactation MeSH
- Dairying MeSH
- Milk metabolism MeSH
- Organic Chemicals MeSH
- Insect Repellents * MeSH
- Cattle parasitology physiology MeSH
- Animals MeSH
- Check Tag
- Cattle parasitology physiology MeSH
- Female MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Names of Substances
- Organic Chemicals MeSH
- oxamate (repellent) MeSH Browser
- Insect Repellents * MeSH
Personal care products have various organic ultraviolet filters (UV filters) in their composition to increase protection against ultraviolet radiation. Some of these products also contain insect repellents in their formulations. Consequently, these compounds reach freshwater ecosystems, exposing aquatic organisms to a cocktail of anthropogenic contaminants. In this study, the joint effects of two most frequently detected UV filters (Benzophenone - 3 (BP3) and Enzacamene (4-MBC)) and joint effects of BP3 combined with an insect repellent (N, N diethyl-3-methylbenzamide - DEET) were evaluated using life-history traits of the aquatic midge Chironomus riparius such as emergence rate, time to emergence and imagoes body weight. The results showed synergistic effects between BP3 and 4-MBC for C. riparius emergence rate. Regarding the effects of BP3 and DEET mixture, our analysis suggests synergism in the case of males but antagonism in the case of females' time to emergence. Our results imply that the effects of UV filters present in sediments within chemical mixtures are complex and that the evaluation of effects using different life-history traits can yield different patterns of responses. This study demonstrates the importance of assessing the combined effects of pollutants used/found concomitantly in aquatic systems for a more accurate risk assessment, as individual chemical testing can underestimate the toxicity of organic UV filters.
- Keywords
- Aquatic organisms, Combined effects, Linear models, Mixture toxicity, Personal care products, Sunscreens,
- MeSH
- Benzophenones toxicity MeSH
- Water Pollutants, Chemical * toxicity MeSH
- Chironomidae * MeSH
- DEET toxicity MeSH
- Ecosystem MeSH
- Larva MeSH
- Sunscreening Agents toxicity MeSH
- Insect Repellents * toxicity MeSH
- Ultraviolet Rays MeSH
- Animals MeSH
- Check Tag
- Male MeSH
- Female MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Names of Substances
- Benzophenones MeSH
- Water Pollutants, Chemical * MeSH
- DEET MeSH
- enzacamene MeSH Browser
- oxybenzone MeSH Browser
- Sunscreening Agents MeSH
- Insect Repellents * MeSH
