Patent Publication Number: US-10306894-B1

Title: Natural mosquito repellant

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of the filing date of U.S. Provisional Patent Application Ser. No. 62/591,338 filed Nov. 28, 2017, entitled NATURAL MOSQUITO REPELLANT, herein incorporated by reference in its entirety. 
    
    
     FIELD OF THE INVENTION 
     The present invention is generally directed to a natural repellent consisting of a soybean oil enriched with specific essential oils that shows a strong and proven repellent activity against  Aedes aegypti, Ae. albopictus, Anopheles stephensi  and  An. gambiae  mosquitoes under laboratory conditions. 
     BACKGROUND 
     Mosquitoes can transmit several diseases including malaria, dengue, chikungunya, yellow fever, Zika virus, filariasis causing millions of deaths every year, mainly children and pregnant women. 
     Mosquito repellents are one of the most important tools to prevent mosquito borne diseases transmission. The most used and long-lasting repellents are the ones containing N,N-diethyl-3-methylbenzamide (DEET) and Icaridin. 
     Although it has been demonstrated their efficacy against mosquito biting, their toxicity and collateral effects on human body are not well characterized [ 1 ]. For this reason, many natural repellents have been developed in order to avoid the issues related to the use of synthetic compounds. Plant essential oils are recognized as interesting insecticide-resources showing no effects on humans and environment. 
     Existing references known as repellents include U.S. Pat. Nos. 4,929,608, 5,716,602, 5,965,137, 6,538,027, 6,548,085, 6,555,121, 6,719,959, 7,144,591, 7,201,926, 7,232,844, 7,344,728, 7,381,431, 7,531,188, 7,858,127, 7,985,432, 8,568,800, 8,647,684, 8,663,615, 8,742,204, 8,999,407, 9,079,152, 9,101,143, 9,210,926, 9,326,524, 9,433,203 and 9,717,240. 
     It is an object of the invention to provide a new, effective and safe formulation for a natural repellent against  Anopheles  mosquitoes, vectors of malaria, and  Aedes  mosquitoes, vectors of dengue, Zika virus, chikungunya and yellow fever. 
     It is an object of the invention to improve upon the deficiencies in the prior art. 
     SUMMARY OF THE INVENTION 
     It is an object of the invention to improve upon the prior art and to provide a formulation and methods of administration thereof for repelling mosquitoes. 
     It is an object of the invention to provide a formulation and methods of administration thereof for repelling  Ae. aegypti, Ae. albopictus, An. stephensi  and  An. gambiae  mosquitoes. 
     These and other objects of the invention are achieved by providing a formulation for repelling mosquitoes, comprising: soybean oil; and at least one essential oil, wherein the amount of soybean oil to the at least one essential oil ranges from 100:1 to 1000:1. 
     In certain embodiments, the at least one essential oil is selected from a group consisting of  Piper aduncum, Nepeta cataria  (Catnip),  Eucalyptus globulus, Pelargonium×asperum  (Geranium) and  Salvia officinalis  and combinations thereof. 
     In certain embodiments, the at least one essential oil includes each and every one of  Piper aduncum, Nepeta cataria  (Catnip),  Eucalyptus globulus, Pelargonium×asperum  (Geranium) and  Salvia officinalis.    
     In certain embodiments, the formulation comprises about 50 ml of soybean oil, about 0.05 ml of  Piper aduncum , about 0.1 ml of  Nepeta cataria  (Catnip), about 0.1 ml of  Eucalyptus globulus , about 0.1 ml of  Pelargonium×asperum  (Geranium) and about 0.1 ml of  Salvia officinalis.    
     In certain embodiments, the formulation repels mosquitoes selected from a group consisting of  Aedes aegypti, Ae. albopictus, Anopheles stephensi  and  An. gambiae.    
     In certain embodiments, the formulation repels mosquitoes selected from a group consisting of  Anopheles  mosquitoes,  Aedes  mosquitoes and mosquitoes that carry vectors of malaria, vectors of dengue, Zika virus, chikungunya and yellow fever. 
     In certain embodiments, the formulation results in a protection period against mosquito bites of about 404 minutes for  Ae. aegypti  mosquitoes. 
     In certain embodiments, the formulation results in a protection period against mosquito bites of about 401.7 minutes for  Ae. albopictus  mosquitoes. 
     In certain embodiments, the formulation results in a protection period against mosquito bites of about 540 minutes for  An. stephensi  mosquitoes. 
     In certain embodiments, the formulation results in a protection period against mosquito bites of about 540 minutes for  An. gambiae  mosquitoes. 
     In certain embodiments, the soybean oil is enriched with the at least one essential oil. 
     In certain embodiments, the at least one essential oil is blended into the soybean oil. 
     Other objects of the invention are achieved by providing a method for repelling mosquitoes, wherein the method includes administering the formulation of claim  1  to mosquitoes including  Anopheles gambiae  and  An. stephensi, Aedes aegypti  and  Ae. albopictus.    
     In certain embodiments, the mosquitoes carry at least one of main vectors of malaria, main vectors of dengue, Zika virus, chikungunya and yellow fever. 
     In certain embodiments, the formulation comprises: soybean oil at 50 ml,  Piper aduncum —essential oil at 0.05 ml,  Nepeta cataria  (Catnip) at 0.1 ml,  Eucalyptus globulus  at 0.1 ml,  Pelargonium×asperum  (Geranium) at 0.1 ml and  Salvia officinalis  at 0.1 ml as a mosquito repellent. 
     Other objects of the invention are achieved by providing methods of administering a formulation comprising: soybean oil at 50 ml,  Piper aduncum —essential oil at 0.05 ml,  Nepeta cataria  (Catnip) at 0.1 ml,  Eucalyptus globulus  at 0.1 ml,  Pelargonium×asperum  (Geranium) at 0.1 ml and  Salvia officinalis  at 0.1 ml as a mosquito repellent. 
     Other objects of the invention and its particular features and advantages will become more apparent from consideration of the following drawings and accompanying detailed description. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention. 
     Other objects of the invention are achieved by providing a formulation for repelling mosquitoes, consisting of: soybean oil; and at least one essential oil, wherein the amount of soybean oil to the at least one essential oil ranges from 100:1 to 1000:1, wherein the at least one essential oil is selected from a group consisting of  Piper aduncum, Nepeta cataria  (Catnip),  Eucalyptus globulus, Pelargonium×asperum  (Geranium) and  Salvia officinalis  and combinations thereof. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1 : Graph showing the repellent activities against  An. stephensi, An. gambiae, Ae. albopictus  and  Ae. aegypti . The first segment describes mosquitoes biting behavior in negative control cages. The other two segments show the repellent effect on mosquito species. 
     
    
    
     DETAILED DESCRIPTION OF INVENTION 
     In the following description, numerous details are set forth for the purpose of explanation. However, one of ordinary skill in the art will realize that the invention may be practiced without the use of these specific details. 
     Materials and Methods 
     Materials 
     Soybean oil (Naissance) and essential oils [ Piper aduncum  [Raintree Formulas, UK],  Nepeta cataria  (Catnip) [Mistic Moments, UK],  Pelargonium×asperum  (Geranium) [Puressentiel, Belgique]  Eucalyptus globulus  and  Salvia officinalis  [Alkemilla s.a.s, Italy]. The formulation containing 0.1%  Piper aduncum,  0.2%  Nepeta cataria,  0.2%  Eucalyptus globulus,  0.2%  Pelagornium×asperum  and 0.2%  Salvia officinalis  in 50 ml of soybean oil was stored at room temperature before testing. 
     Formulation 
     
       
         
           
               
               
               
             
               
                   
                   
               
               
                   
                 Components 
                 ml 
               
               
                   
                   
               
             
            
               
                   
               
            
           
           
               
               
               
            
               
                   
                 Soybean oil 
                 50 
               
               
                   
                   Piper   aduncum  - essential oil 
                 0.05 
               
               
                   
                   Nepeta   cataria  (Catnip) - essential oil 
                 0.1 
               
               
                   
                   Eucalyptus   globulus  - essential oil 
                 0.1 
               
               
                   
                 
                   Pelargonium 
                   x 
                   asperum 
                 
                 0.1 
               
               
                   
                 ( Geranium ) - essential oil 
                   
               
               
                   
                   Salvia   officinalis  - essential oil 
                 0.1 
               
               
                   
                 TOTAL 
                 50 
               
               
                   
                   
               
            
           
         
       
     
     Mosquitoes 
     All four mosquito species used in our experiments were reared in the insectary facilities of the School of Biosciences and Biotechnology at the University of Camerino, Italy. Mosquitoes were maintained in standard rearing conditions into small cages (30 cm×30 cm×30 cm) at a temperature of 28° C. and 80±5% relative humidity, with a photoperiod of 12 h light/dark cycle. Adults were provided with 5% glucose solution in water soaked on cotton pads. 50 nulliparous female mosquitoes for each species of 5-10 days were placed in 8 different cages. Sugar cotton pads were removed 2 hours before performing the tests. 
     Repellent Activity 
     The repellent activity was tested on the inventors as volunteers. 
     The repellent activity testing time against mosquito were: from 9.00 am to 6.00 μm for  Anopheles  species and from 9.00 am to 5.00 μm for  Aedes  mosquitoes. 
     Before repellent application, the left hand and forearm of human volunteers were washed with unscented soap, cleaned thoroughly with distilled water and dried for 20 min. Both arms were covered with rubber sleeve with a window area of 7 cm×40 cm. The left hand/forearm were used for treatment and the right arm for control. About 0.2 ml of the formulation was carefully applied on the left forearm (until elbow) and hand. After applying the repellent, the volunteer was careful to not rub, touch or wet the treated area. The right forearm, which acted as a control, was not treated and was exposed for up to 3 minutes into a mosquito cage (30 cm×30 cm×30 cm) contained 50 nulliparous female mosquitoes (5-10 days old). The control test continued until at least 20 fed females occurred in a three-minute period. The repellency test was carried out putting the treated hand/forearm for 540 min and 480 min into cages containing 50 nulliparous female mosquitoes of  Anopheles  and  Aedes  species, respectively. The mosquitoes landing on arm to perform a blood meal were recorded. 
     Results and Discussion 
     The following results are referred to three independent replicates. 
     Concerning control cages of all four mosquito species, after few seconds from the exposure, more than 15-20 mosquitoes landing on the arm having a blood meal. 
     In the repellent assessment activity, we observed this behavior (Table 1;  FIG. 1 ): 
     In  Aedes aegypti  the first bite was recorded after 404.0±8.72 min post-application and after 480 min the percentage of protection was 97.3%. 
     In  Aedes albopictus  the first bite was recorded after 401.7±10.14 min post-application and after 480 min the percentage of protection was 96.7%. 
     In  Anopheles stephensi  and  An. gambiae  we observed no mosquitoes bite until 540 min post-application. 
     
       
         
           
               
             
               
                 TABLE 1 
               
             
            
               
                   
               
               
                 Repellent activities against  Ae .  aegypti ,  Ae .  albopictus ,  
               
               
                   An.   stephensi  and  An.   gambiae . 
               
            
           
           
               
               
               
               
               
            
               
                   
                 Mean of 
                   
                 Mean  
                 Ratio of Mean  
               
               
                   
                 protection 
                   
                 of No 
                 mosquito  
               
               
                 Mosquito 
                 time 
                 % 
                 mosquito 
                 bite/Mean of 
               
               
                 species 
                 (min) ± SEM 
                 Repellency 
                 bite ± SEM 
                 protection time 
               
               
                   
               
            
           
           
               
               
               
               
               
            
               
                 
                   Ae. 
                   aegypti 
                 
                  404 ± 8.72 
                 97.3 (480 min) 
                 1.67 ± 0.67 
                 0.0041 
               
               
                 
                   Ae. 
                   albopictus 
                 
                 401.7 ± 10.14 
                 96.7 (480 min) 
                 1.33 ± 0.33 
                 0.0033 
               
               
                   An .  stephensi   
                 540 ± 0  
                  100 (540 min) 
                 0 ± 0 
                 0 
               
               
                   An .  gambiae   
                 540 ± 0  
                  100 (540 min) 
                 0 ± 0 
                 0 
               
               
                   
               
            
           
         
       
     
     Description of Each Ingredient Used in Formulation 
     Soybean Oil: 
     Properties: 
     Soybean oil is widely employed in massages and skin and body care, since it helps to reduce and prevent stretch marks, maintaining the derma young and soft. Moreover, it carries out a good hydrating activity, making a protective film on skin able to slow down the skin dehydration, improving, therefore, its tone and elasticity. It can be also used to make hair mask and hands hydrating creams. Finally, it is an excellent base in aromatherapy. 
     Another formulation containing glycerin, lecithin, vanillin, oils of coconut, geranium, and 2% soybean oil, has been found able to achieve similar repellency to DEET, providing 7.2 hours mean protection time against a dengue vector. It would appear that the soybean oil in the formulation helps only contributes to repellency as it is not repellent when evaluated on its own [2]. 
     In 2015, Soonwera and Phasomkusolsil [3] evaluated the efficacy of Thai herbal essential oils as green repellents against mosquito vectors. Plant products were applied onto the forearm of human volunteers and they were evaluated. The results for plant oils repellency against  Aedes aegypti  and  Culex quinquefasciatus  were summarized in Table 2 and Table 3. 
     
       
         
           
               
             
               
                 TABLE 2 
               
             
            
               
                   
               
               
                 Repellency activities of two herbal essential  
               
               
                 oils which diluted in three diluents at 0.33 μl/cm 2   
               
               
                 (coconut oil, soybean oil and olive oil) against  Aedes   aegypti.   
               
            
           
           
               
               
               
               
            
               
                   
                 Protection  
                 % 
                 % 
               
               
                 Herbal essential oils  
                 time (min) a   
                 Biting 
                 Protection 
               
               
                   
               
            
           
           
               
               
               
               
            
               
                 Ylang ylang oil + coconut oil 
                 88.7 ± 10.4 b   
                 1.1 
                 98.9 
               
               
                 Ylang ylang oil + soybean oil 
                 10.50 ± 2.1 c   
                 2.4 
                 97.6 
               
               
                 Ylang ylang oil + olive oil 
                 85.5 ± 12.0 b   
                 1.4 
                 98.6 
               
               
                 Lemongrass oil + coconut oil 
                 85.5 ± 10.5 b   
                 1.1 
                 98.9 
               
               
                 Lemongrass oil + soybean oil 
                 72.0 ± 12.4 b   
                 2.6 
                 97.4 
               
               
                 Lemongrass oil + olive oil 
                 60.0 ± 12.5 b   
                 1.2 
                 98.8 
               
               
                 DEET 20% (w/w)  
                 155.0 ± 7.1 a   
                 1.5 
                 98.5 
               
               
                 (Sketolene Shield ®) 
                   
                   
                   
               
               
                 IR3535 12.5% (w/w)  
                 3.0 ± 0 c   
                 21.0 
                 79.0 
               
               
                 (Johnson&#39;s Baby Clear 
                   
                   
                   
               
               
                 Lotion ®) 
               
               
                   
               
            
           
         
       
     
     
       
         
           
               
             
               
                 TABLE 3 
               
             
            
               
                   
               
               
                 Repellency activities of two herbal essential  
               
               
                 oils which diluted in three diluents at 0.33 μl/cm 2    
               
               
                 against  Culex   quinquefasciatus . 
               
            
           
           
               
               
               
               
            
               
                   
                 Protection 
                 % 
                 % 
               
               
                 Herbal essential oils 
                 time (min) a   
                 Biting 
                 Protection 
               
               
                   
               
            
           
           
               
               
               
               
            
               
                 Ylang ylang oil + coconut oil 
                 126.7 ± 5.8   b     
                 0.8 
                 99.2 
               
               
                 Ylang ylang oil + soybean oil 
                 60.0 ± 0   d         
                 1.2 
                 98.8 
               
               
                 Ylang ylang oil + olive oil 
                  85.5 ± 12.0   c     
                 1.4 
                 98.6 
               
               
                 Lemongrass oil + coconut oil 
                 115.5 ± 10.4   b     
                 1.1 
                 98.9 
               
               
                 Lemongrass oil + soybean oil 
                  84.0 ± 25.1   c     
                 1.7 
                 98.3 
               
               
                 Lemongrass oil + olive oil 
                 170.0 ± 9.0   a     
                 1.2 
                 98.8 
               
               
                 DEET 20% (w/w)  
                 182.0 ± 12.2   a     
                 1.5 
                 98.5 
               
               
                 (Sketolene Shield ®) 
                   
                   
                   
               
               
                 IR3535 12.5% (w/w)  
                 3.0 ± 0 c   
                 24.2 
                 75.8 
               
               
                 (Johnson&#39;s Baby Clear 
                   
                   
                   
               
               
                 Lotion ®) 
               
               
                   
               
            
           
         
       
     
     The same results were found during experiment, testing the soybean oil alone as control. 
     The formulation as set forth is a natural repellent and is a blend of plant essential oils in 50 ml of soybean oil. We evaluated the repellency activity under laboratory conditions against Ae.  aegypti, Ae. albopictus, An. gambiae  and  An. stephensi  mosquitoes and we obtained results that are very promising if compared with those of Soonwera and Phasomkusolsil. 
       Piper aduncum  Essential Oil: 
     In 2009, Misni et al [4] investigating the repellency activity under laboratory conditions against  Ae. albopictus  using human volunteers, published this data “At 0.4 g, the essential oil gave a high protection (95.2%) against  Ae. albopictus  bites or landing at 2 h post-application. The percentage of protection was reduced to 83.3% after 4 h, 64.5% after 6 h, and 51.6% after 8 h post-application”. 
     In 2017, Mamood et al [5] have studied the effectiveness of 10%  Piper aduncum  essential oil in ethanol and in three different formulations: ointment, cream and gel against  Aedes aegypti  mosquitoes under laboratory conditions. “The ointment formulation provided a protection time of 182.5±16.01 min. Meanwhile, the cream formulation provided a protection time of 162.5±6.29 min. As the cream and ointment formulations displayed better repellent properties than the gel formulation, they appear to be the most promising  P. aduncum  formulations to be developed and commercialized as alternatives to synthetic repellents”. 
       Eucalyptus  Essential Oil: 
     In 2013, Sritabutra and Soonwera [6] investigated the mosquito repellent of eight essential oils including  Eucalyptus citriodara  against  Aedes aegypti  and  Culex quinquefasciatus  under laboratory conditions using human volunteers. 
       Eucalyptus citriodara  was used in a 10% formulation using as diluting or olive oil or coconut oil. 
     In olive oil,  Eucalyptus citriodara  showed a protection time of 51.75±25.50 min against  Ae. aegypti  and 67.50±42.53 min against  Cx. quinquefasciatus.    
     In coconut oil,  Eucalyptus citriodara  showed a protection time of 82.50±19.21 min against  Ae. aegypti  and 70.50±9.00 min against  Cx. quinquefasciatus.    
     In 2017, Lalthazuali and Mathew [ 7 ] evaluated mosquito repellent activity of volatile oils from selected aromatic plants included  Eucalyptus globulus . The test solution was prepared as 20% essential oil in ethanol whereas essential oil blend was prepared as 5% concentration. 3-5 days-old female adult  Aedes aegypti  mosquitoes were used for repellency screening. The  E. globulus  oil exhibited mosquito repellency only up to 1½ h. 
     In 2016, Auysawasdi et al [8] studied the repellency capability of essential oil extracted from  Eucalyptus globulus  at various concentrations (5, 10, 15, 20, 25%) against female mosquitoes of  Aedes aegypti  and  Anopheles dirus . The researchers observed that the essential oil (25% concentration) supplemented with 5% vanillin, gave the longest lasting period against the mosquitoes as follows: 144 min for  Ae. aegypti  and 390 min for  An. dirus.    
     Catnip ( Nepeta cataria ) Essential Oil: 
     In 2016, Patel at al [9] published a review entitled “EPA-Registered Repellents for Mosquitoes Transmitting Emerging Viral Disease”. The main review objective was to identify which EPA-registered mosquito repellents provide the best protection against target mosquitoes. In the article, the table “Summary of Available Data for Commonly Used Repellents” about catnip, we found that the available results are inconsistent due to limited data. 
     In 2007, Webb and Russell [10] tested the repellency of  Nepeta cataria  (catnip) against  Aedes aegypti, Aedes vigilax, Culex annulirostris , and  Culex quinquefasciatus , comparing it with a blend of natural plant extracts and DEET on human skin. The catnip and natural plant extract blend did not provide the same level of protection from biting mosquitoes as DEET. There were significant differences in the level of protection provided by catnip to the four species of mosquito, with mean protection times ranging from 0 min for  Ae. Aegypti  up to 240±60 min for  Cx. quinquefasciatus.    
     In 2006, Amer and Mehlhorn [11] evaluated the repellency effect of forty-one essential oils against  Aedes, Anopheles  and  Culex  mosquitoes. 
     In the paper, the table representing “the protection period and percentage of repellency of tested oils, DEET, and Bayrepel against the three mosquito species”, about catnip we found these data: Protection Period (PP) of 480 min for  Aedes aegypti,  480 min against  Anopheles stephensi  and 480 min against  Culex quinquefasciatus . However, these PP were obtained using a 20% solution of catnip in a complex formulation containing 20% Genapol, 10% PEG (PolyEthylene Glycol), 20% Ethanol, 50% Water. 
     Conversely, a 20% catnip solution in ethanol alone exhibited these protection periods: less of 200 min against  Aedes aegypti , about 300 min against  Anopheles stephensi  and 480 min against  Culex quinquefasciatus.    
     Geranium Essential Oil: 
     About the possible repellent activity of Geranium essential oil against mosquito species, the scientific literature is lacking. 
       Mei Mei  Cream is a commercial repellent containing Citronella and Geranium oils. 
     In 2006, Chang et al [12] evaluating the repellency of  Cinnamomum cassia  bark compounds and cream containing  cassia  oil to  Aedes aegypti  under laboratory conditions, tested also the activity of this commercial product. In the publication, the table 6 shows the repellency of  cassia  oil containing cream and also  Mei Mei  Cream against  Aedes aegypti -female mosquitoes. Concerning  Mei Mei  Cream the percentages (%) of repellency were: 97 (±1.3) at 30 min; 97 (±2.7) at 50 min; 85 (±1.2) at 70 min; 44 (±1.7) at 90 min and 27 (±2.3) at 120 min. 
     In 2000, Govere et al [13] evaluating the possible use of three local plants [fever tea ( Lippia javanica ), rose geranium ( Pelargonium reniforme ) and lemon grass ( Cymbopogon excavates )] as repellents against laboratory reared  Anopheles arabiensis  mosquitoes in South Africa region, they achieved these results: “All three alcohol plant extracts provided significantly more protection than alcohol control. The alcohol plant extract of  L. javanica  provided 76.7% protection against  An. arabiensis  after a four hour period, and  C. excavatus  and  P. reniforme  (rose geranium) provided 66.7% and 63.3% protection for three hours, respectively. At five hours post application only  L. javanica  alcohol extract provided appreciable protection (59.3%) against  An. arabiensis”.    
       Salvia officinalis  Essential Oil: 
     In 2012, Conti et al [14] evaluated the repellent activity of essential oils extracted from fresh air dried leaves of  Salvia dorisiana, S. longifolia , and  S. sclarea  against  Aedes albopictus  by using the human-bait technique. Analyzing carefully the results, we observed that “ Salvia dorisiana  was the most effective oil: at the two higher dosages, it gave almost complete protection (with a protective efficacy of 90.99% and 95.62%, respectively) for 90 min”. 
     Compared to the data reported in literature, our formulation, made of ingredient listed above, gave much better results in terms of performance and safety, considering that in our repellent there are no traces of chemical compounds such as DEET, icaridin and alcohols. 
     Another crucial feature is the rate between repellent efficacy and compounds concentration. Although we used lower concentration for each essential oil, we obtained a longer protection compared to the results described in literature. Particularly, our essential oil formulation in soybean oil has a great repellency activity under laboratory conditions against  Ae. aegypti, Ae. albopictus, An. gambiae  and  An. stephensi  mosquitoes. Concerning  Ae. aegypti  we observed that the protection period was 404±8.72 min and that after 480 min the percentage of protection was 97.3%; in  Ae. albopictus  401.7±10.14 min post-application and after 480 min the percentage of protection was 96.7%. In  An. stephensi  and  An. gambiae  we observed no mosquitoes bite until 540 min post-application. 
     In conclusion, the repellent as disclosed presents four crucial features: i) it&#39;s safe, natural and ecological formulation; ii) it shows strong repellent activities compared to the other commercial repellents; iii) it is cheaper and iv) in addition to the repellent action, the repellant formulation, being a soybean oil-based product, has an intrinsic moisturizing, anti-shrinkage and protector against UV rays. 
     Although the data reported are referred to  Anopheles  and  Aedes  mosquitoes, vectors of malaria, dengue, Zika virus, chikungunya, yellow fever, our formulation can be considered effective also against other mosquito genera such as  Culex  mosquitoes. 
     The above-mentioned results suggest that the repellent can represent a powerful competitor against the common used chemical products which toxicity and collateral effects on human are not well characterized. 
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