1
|
Hayes CC, Schal C. Repellency of N,N-diethyl-3-methylbenzamide (DEET) during host-seeking behavior of bed bugs (Hemiptera: Cimicidae) in binary choice olfactometer assays. JOURNAL OF MEDICAL ENTOMOLOGY 2024; 61:1016-1025. [PMID: 38839102 PMCID: PMC11239792 DOI: 10.1093/jme/tjae073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2024] [Revised: 05/08/2024] [Accepted: 05/17/2024] [Indexed: 06/07/2024]
Abstract
The bed bug (Cimex lectularius L.) is one of the most prolific and burdensome indoor pests, and suppression of bed bug populations is a global priority. Understanding bed bug behavior is important to the development of new tactics for their control. Major gaps exist in our understanding of how host cues, insecticide resistance, and exposure modality impact the repellency of formulated products to bed bugs. Here, we validate the use of a binary choice olfactometer for assessing bed bug repellency behaviors using N,N-diethyl-3-methylbenzamide (DEET) in a dose-dependent manner, while considering the role of host-associated stimuli (with vs. without CO2), exposure modality (olfactory vs. olfactory and contact), and resistance status (susceptible vs. resistant) on repellency. We observed that host-seeking insecticide-susceptible bed bugs were repelled only when olfactorily exposed to high concentrations of DEET. However, exposure to DEET by contact repelled insecticide-susceptible bed bugs at 100-fold lower dose of DEET. Further, we demonstrate for the first time that insecticide-resistant bed bugs were significantly more responsive to DEET than susceptible bed bugs. We conclude that the 2-choice olfactometer is an effective tool for assessing the behavioral responses of bed bugs to spatial and contact repellents.
Collapse
Affiliation(s)
- Christopher C Hayes
- Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, NC, USA
| | - Coby Schal
- Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, NC, USA
| |
Collapse
|
2
|
Batume C, Mulongo IM, Ludlow R, Ssebaale J, Randerson P, Pickett JA, Mukisa IM, Scofield S. Evaluating repellence properties of catnip essential oil against the mosquito species Aedes aegypti using a Y-tube olfactometer. Sci Rep 2024; 14:2269. [PMID: 38280895 PMCID: PMC10821859 DOI: 10.1038/s41598-024-52715-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Accepted: 01/23/2024] [Indexed: 01/29/2024] Open
Abstract
The mosquito species Aedes aegypti (L.) is known to act as a vector in the transmission of various diseases, including dengue fever and yellow fever. The use of insect repellents is one of precautionary measures used to mitigate the risk of these diseases in humans by reducing mosquito biting. Nepetalactone, a potent natural insect repellent primarily found in catnip (Nepeta cataria) essential oil, has emerged as a promising candidate for mosquito repellence. Here, we evaluated the potential of catnip essential oil (> 95% nepetalactone) for use as a mosquito repellent. Using a Y-tube olfactometer and human hands as an attractant, we analysed the effectiveness of catnip oil at repelling the mosquito species Aedes aegypti. We tested a range of dilutions of catnip essential oil and found that concentrations as low as 2% were effective at repelling > 70% of mosquitoes for between one and four hours after repellent application. These findings suggest that nepetalactone could potentially be used as a natural, effective alternative to synthetic mosquito repellents, thereby offering protection against vector-borne diseases.
Collapse
Affiliation(s)
- Charles Batume
- Department of Entomology, Uganda Virus Research Institute (UVRI), Entebbe, Uganda
| | | | | | | | | | | | - Ivan M Mukisa
- Department of Food Technology and Nutrition, Makerere University, Kampala, Uganda
| | | |
Collapse
|
3
|
Shin N, Lascarez-Lagunas LI, Henderson AL, Martínez-García M, Karthikraj R, Barrera V, Sui SH, Kannan K, Colaiácovo MP. Altered gene expression linked to germline dysfunction following exposure of Caenorhabditis elegans to DEET. iScience 2024; 27:108699. [PMID: 38299026 PMCID: PMC10829882 DOI: 10.1016/j.isci.2023.108699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Revised: 10/13/2023] [Accepted: 12/06/2023] [Indexed: 02/02/2024] Open
Abstract
N,N-diethyl-meta-toluamide (DEET) is a commonly used synthetic insect repellent. Although the neurological effects of DEET have been widely investigated, its effects on the germline are less understood. Here, we show that exposure of the nematode Caenorhabditis elegans, which is highly predictive of mammalian reprotoxicity, resulting in internal DEET levels within the range detected in human biological samples, causes activation of p53/CEP-1-dependent germ cell apoptosis, altered meiotic recombination, chromosome abnormalities, and missegregation. RNA-sequencing analysis links DEET-induced alterations in the expression of genes related to redox processes and chromatin structure to reduced mitochondrial function, impaired DNA double-strand break repair progression, and defects during early embryogenesis. We propose that Caenorhabditis elegans exposure to DEET interferes with gene expression, leading to increased oxidative stress and altered chromatin structure, resulting in germline effects that pose a risk to reproductive health.
Collapse
Affiliation(s)
- Nara Shin
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA
| | | | - Ayana L. Henderson
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA
| | - Marina Martínez-García
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA
| | - Rajendiran Karthikraj
- Wadsworth Center, New York State Department of Health, Empire State Plaza, Albany, NY 12237, USA
| | - Victor Barrera
- Bioinformatics Core, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA
| | - Shannan Ho Sui
- Bioinformatics Core, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA
| | - Kurunthachalam Kannan
- Wadsworth Center, New York State Department of Health, Empire State Plaza, Albany, NY 12237, USA
- Department of Environmental Health Sciences, School of Public Health, University at Albany, State University of New York, Albany, NY 12237, USA
| | - Mónica P. Colaiácovo
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA
| |
Collapse
|
4
|
Luker HA. A critical review of current laboratory methods used to evaluate mosquito repellents. FRONTIERS IN INSECT SCIENCE 2024; 4:1320138. [PMID: 38469342 PMCID: PMC10926509 DOI: 10.3389/finsc.2024.1320138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Accepted: 01/02/2024] [Indexed: 03/13/2024]
Abstract
Pathogens transmitted by mosquitoes threaten human health around the globe. The use of effective mosquito repellents can protect individuals from contracting mosquito-borne diseases. Collecting evidence to confirm and quantify the effectiveness of a mosquito repellent is crucial and requires thorough standardized testing. There are multitudes of methods to test repellents that each have their own strengths and weaknesses. Determining which type of test to conduct can be challenging and the collection of currently used and standardized methods has changed over time. Some of these methods can be powerful to rapidly screen numerous putative repellent treatments. Other methods can test mosquito responses to specific treatments and measure either spatial or contact repellency. A subset of these methods uses live animals or human volunteers to test the repellency of treatments. Assays can greatly vary in their affordability and accessibility for researchers and/or may require additional methods to confirm results. Here I present a critical review that covers some of the most frequently used laboratory assays from the last two decades. I discuss the experimental designs and highlight some of the strengths and weaknesses of each type of method covered.
Collapse
Affiliation(s)
- Hailey A. Luker
- Molecular Vector Physiology Laboratory, Department of Biology, New Mexico State University, Las Cruces, NM, United States
| |
Collapse
|
5
|
Almeida AR, Oliveira ND, Pinheiro FASD, Morais WAD, Ferreira LDS. Challenges encountered by natural repellents: Since obtaining until the final product. PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2023; 195:105538. [PMID: 37666610 DOI: 10.1016/j.pestbp.2023.105538] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 07/12/2023] [Accepted: 07/13/2023] [Indexed: 09/06/2023]
Abstract
Vector-borne diseases, particularly the arboviruses dengue, Zika, chikungunya, and yellow fever caused by the Aedes aegypti mosquito, have been driving the use of repellents worldwide. The most representative synthetic repellent, DEET stands out as the market's oldest and most efficient repellent. It is considered a reference standard but presents considerable toxicity, not recommended for children up to 6 months old and pregnant women. For this reason, alternatives have been sought, and natural repellents derived mainly from essential oils have been studied, highlighting the essential oils of lemon (Corymbia citriodora), citronella (Cympobogon sp.), Andiroba (Carapa guianensis). However, the development and commercialization of products containing natural repellents are significantly lower when compared to DEET and other synthetic repellents. In order to understand the reasons, aspects related to safety, mechanism of action, efficacy as well development and complexity of the products were evaluated. It is concluded that, as for safety, there is lacking information in the literature regarding the effects on non-target organisms and robust toxicity data. The mechanism of action is based on theories, with less information on the exact mode of action, molecular targets, and interaction with the olfactory and taste receptors of insects. Despite being a current trend to search for actives from natural sources highly present in essential oils, however they reduced action time because due to rapid evaporation after application to the skin, thus requiring repellent vehicles. The development and complexity related to these products bring challenging aspects, beginning on the plant cultivation and extraction processes to produce essential oils with a more homogeneous chemical composition towards the formulation stabilization processes due to fast evaporation and short action time, with the use of pharmaceutical technology such as encapsulation techniques.
Collapse
Affiliation(s)
- Addison Ribeiro Almeida
- Department of Pharmacy, Laboratório de Farmacotécnica, Federal University of Rio Grande do Norte, Natal, Rio Grande do Norte, Brazil; Department of Pharmacy, Laboratory of Quality Control of Medicines (LCQMed), Federal University of Rio Grande do Norte, Natal, Rio Grande do Norte, Brazil.
| | - Nicolas Dantas Oliveira
- Department of Pharmacy, Laboratório de Farmacotécnica, Federal University of Rio Grande do Norte, Natal, Rio Grande do Norte, Brazil; Department of Pharmacy, Laboratory of Quality Control of Medicines (LCQMed), Federal University of Rio Grande do Norte, Natal, Rio Grande do Norte, Brazil
| | | | - Waldenice Alencar de Morais
- Department of Pharmacy, Laboratório de Farmacotécnica, Federal University of Rio Grande do Norte, Natal, Rio Grande do Norte, Brazil.
| | - Leandro De Santis Ferreira
- Department of Pharmacy, Laboratory of Quality Control of Medicines (LCQMed), Federal University of Rio Grande do Norte, Natal, Rio Grande do Norte, Brazil.
| |
Collapse
|
6
|
Priya SS, Vasantha-Srinivasan P, Altemimi AB, Keerthana R, Radhakrishnan N, Senthil-Nathan S, Kalaivani K, Chandrasekar N, Karthi S, Ganesan R, Alkanan ZT, Pal T, Verma OP, Proćków J. Bioactive Molecules Derived from Plants in Managing Dengue Vector Aedes aegypti (Linn.). Molecules 2023; 28:molecules28052386. [PMID: 36903635 PMCID: PMC10005433 DOI: 10.3390/molecules28052386] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2023] [Revised: 02/13/2023] [Accepted: 03/02/2023] [Indexed: 03/08/2023] Open
Abstract
Mosquitoes are the potential vectors of several viral diseases such as filariasis, malaria, dengue, yellow fever, Zika fever and encephalitis in humans as well as other species. Dengue, the most common mosquito-borne disease in humans caused by the dengue virus is transmitted by the vector Ae. aegypti. Fever, chills, nausea and neurological disorders are the frequent symptoms of Zika and dengue. Thanks to various anthropogenic activities such as deforestation, industrialized farming and poor drainage facilities there has been a significant rise in mosquitoes and vector-borne diseases. Control measures such as the destruction of mosquito breeding places, a reduction in global warming, as well as the use of natural and chemical repellents, mainly DEET, picaridin, temephos and IR-3535 have proven to be effective in many instances. Although potent, these chemicals cause swelling, rashes, and eye irritation in adults and children, and are also toxic to the skin and nervous system. Due to their shorter protection period and harmful nature towards non-target organisms, the use of chemical repellents is greatly reduced, and more research and development is taking place in the field of plant-derived repellents, which are found to be selective, biodegradable and harmless to non-target species. Many tribal and rural communities across the world have been using plant-based extracts since ancient times for various traditional and medical purposes, and to ward off mosquitoes and various other insects. In this regard, new species of plants are being identified through ethnobotanical surveys and tested for their repellency against Ae. aegypti. This review aims to provide insight into many such plant extracts, essential oils and their metabolites, which have been tested for their mosquitocidal activity against different life cycle forms of Ae. Aegypti, as well as for their efficacy in controlling mosquitoes.
Collapse
Affiliation(s)
- Sridhar Shanmuga Priya
- Department of Biotechnology, St. Peter’s Institute of Higher Education Research, Chennai 600077, India
| | - Prabhakaran Vasantha-Srinivasan
- Department of Bioinformatics, Saveetha School of Engineering, Saveetha Institute of Medical 17 and Technical Sciences (SIMATS), Chennai 602105, India
| | - Ammar B. Altemimi
- Department of Food Science, College of Agriculture, University of Basrah, Basrah 61004, Iraq
- College of Medicine, University of Warith Al-Anbiyaa, Karbala 56001, Iraq
| | - Ramji Keerthana
- Department of Biotechnology, RV College of Engineering, Bangalore 560059, India
| | - Narayanaswamy Radhakrishnan
- Department of Biochemistry, Saveetha Medical College and Hospital, Saveetha Institute of Medical and Technical Sciences (SIMATS), Chennai 602105, India
| | - Sengottayan Senthil-Nathan
- Division of Bio-Pesticides and Environmental Toxicology, Sri Paramakalyani Centre for 14 Excellence in Environmental Sciences, Manonmaniam Sundaranar University, Alwarkurichi, 15, Tirunelveli 627412, India
- Correspondence: (S.S.-N.); (J.P.)
| | - Kandasamy Kalaivani
- Post Graduate and Research Centre, Department of Zoology, Sri Parasakthi College for Women, Courtrallam 627802, India
| | | | - Sengodan Karthi
- Department of Entomology, College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY 40503, USA
| | - Raja Ganesan
- Institute for Liver and Digestive Diseases, College of Medicine, Hallym University, Chuncheon 24252, Republic of Korea
| | - Zina T. Alkanan
- Department of Food Science, College of Agriculture, University of Basrah, Basrah 61004, Iraq
| | - Tarun Pal
- Department of Biotechnology, Vignan’s Foundation for Science, Technology and Research, Vadlamudi, Guntur 522213, India
| | - Om Prakash Verma
- Department of Molecular and Cellular Engineering, Jacob Institute of Biotechnology and Bioengineering, Sam Higginbottom University of Agriculture, Technology and Sciences, Prayagraj 211007, India
| | - Jarosław Proćków
- Department of Plant Biology, Institute of Environmental Biology, Wrocław University of Environmental and Life Sciences, Kożuchowska 5b, 51-631 Wrocław, Poland
- Correspondence: (S.S.-N.); (J.P.)
| |
Collapse
|
7
|
Shelomi M. Thiamine (vitamin B1) as an insect repellent: a scoping review. BULLETIN OF ENTOMOLOGICAL RESEARCH 2022; 112:431-440. [PMID: 35199632 DOI: 10.1017/s0007485321001176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
While the desire for systemic repellents is high, ineffective repellents put one at risk of insect-vectored pathogens. Vitamin B1, or thiamine, has been touted as a systemic insect repellent since 1943, and denounced as an ineffective placebo for just as long. This paper presents a scoping review of 104 relevant case reports, research studies, and review articles to trace the evolution of this idea and identify an evidence-based, scientific consensus. Reports of thiamine's systemic repellency are primarily anecdotal and based on uncontrolled trials and/or used bite symptoms as a proxy for reduced biting. Controlled experiments on insect landing and feeding found no evidence of repellency. Of the 49 relevant review papers, 16 insect bite prevention guidelines, and 4 government documents, none after the 1990s claimed thiamine is a repellent. The findings of this review are that thiamine cannot repel arthropods in any dosage or route of administration. Due to limited available evidence, the possibility that thiamine reduces the subjective symptoms of insect bites cannot currently be ruled out. Unfortunately, many medical professionals and travelers today still believe thiamine may be effective despite the evidence stating otherwise. Continued promotion of debunked repellents on the commercial market poses a serious risk in countries with the endemic, mosquito-vectored disease.
Collapse
Affiliation(s)
- Matan Shelomi
- Department of Entomology, National Taiwan University, Taipei, Taiwan
| |
Collapse
|
8
|
Paichitrojjana A, Chalermchai T. Comparison of in vitro Killing Effect of N, N-Diethyl-Meta-Toluamide (DEET) versus Permethrin on Demodex folliculorum. Clin Cosmet Investig Dermatol 2022; 15:1301-1307. [PMID: 35847418 PMCID: PMC9278725 DOI: 10.2147/ccid.s376454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Accepted: 07/06/2022] [Indexed: 11/23/2022]
Abstract
Background There is no single effective treatment for demodicosis; successful treatment requires a multimodal approach. Relapse or recurrence of demodicosis is relatively high, making the therapy challenging. Several reports have documented the successful treatment of demodicosis with acaricidal agents, which aimed at reducing the excessive number of Demodex mites and improving the patients' symptoms. Reports of irritation and resistance to topical acaricidal agents have led to the search for effective alternative treatments. Materials and Methods A total of 100 standardized skin surface biopsy (SSSB) biopsy slides from 100 patients with demodicosis were randomly divided into five groups, each with 20 slides exposed to immersion oil, N, N-diethyl-meta-toluamide (DEET) 5%, 10%, 20%, and permethrin 1%, respectively. The microscopic evaluation started immediately after the test agents exposed the mites. The survival time (ST) was defined as the interval between the first exposure of Demodex folliculorum to the test agents to the time the movements ceased. Results The differences between the median ST of DEET 5% (44 min), 10% (22 min), and 20% (14 min) were significant when compared to the negative control group (240 min) with p<0.001, <0.001, <0.001, respectively. While the median ST of permethrin 1% (42 min) was not significantly different from the median ST of DEET 5% (p=0.7395). Conclusion This study demonstrated the dose-related acaricidal effect of DEET on D. folliculorum. The survival times of DEET 5%, 10%, and 20% were significantly shorter than the negative control (immersion oil). DEET 5% had a comparable in vitro killing effect as permethrin 1%. Further in vivo studies are necessary to determine the clinical efficacy in patients with demodicosis.
Collapse
Affiliation(s)
- Anon Paichitrojjana
- School of Anti-Aging and Regenerative Medicine, Mae Fah Luang University, Bangkok, Thailand
| | - Thep Chalermchai
- School of Anti-Aging and Regenerative Medicine, Mae Fah Luang University, Bangkok, Thailand
| |
Collapse
|
9
|
Lantos PM, Rumbaugh J, Bockenstedt LK, Falck-Ytter YT, Aguero-Rosenfeld ME, Auwaerter PG, Baldwin K, Bannuru RR, Belani KK, Bowie WR, Branda JA, Clifford DB, DiMario FJ, Halperin JJ, Krause PJ, Lavergne V, Liang MH, Meissner HC, Nigrovic LE, Nocton JJJ, Osani MC, Pruitt AA, Rips J, Rosenfeld LE, Savoy ML, Sood SK, Steere AC, Strle F, Sundel R, Tsao J, Vaysbrot EE, Wormser GP, Zemel LS. Clinical Practice Guidelines by the Infectious Diseases Society of America (IDSA), American Academy of Neurology (AAN), and American College of Rheumatology (ACR): 2020 Guidelines for the Prevention, Diagnosis and Treatment of Lyme Disease. Clin Infect Dis 2021; 72:e1-e48. [PMID: 33417672 DOI: 10.1093/cid/ciaa1215] [Citation(s) in RCA: 142] [Impact Index Per Article: 47.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Indexed: 12/13/2022] Open
Abstract
This evidence-based clinical practice guideline for the prevention, diagnosis, and treatment of Lyme disease was developed by a multidisciplinary panel representing the Infectious Diseases Society of America (IDSA), the American Academy of Neurology (AAN), and the American College of Rheumatology (ACR). The scope of this guideline includes prevention of Lyme disease, and the diagnosis and treatment of Lyme disease presenting as erythema migrans, Lyme disease complicated by neurologic, cardiac, and rheumatologic manifestations, Eurasian manifestations of Lyme disease, and Lyme disease complicated by coinfection with other tick-borne pathogens. This guideline does not include comprehensive recommendations for babesiosis and tick-borne rickettsial infections, which are published in separate guidelines. The target audience for this guideline includes primary care physicians and specialists caring for this condition such as infectious diseases specialists, emergency physicians, internists, pediatricians, family physicians, neurologists, rheumatologists, cardiologists and dermatologists in North America.
Collapse
Affiliation(s)
- Paul M Lantos
- Duke University School of Medicine, Durham, North Carolina, USA
| | | | | | - Yngve T Falck-Ytter
- Case Western Reserve University, VA Northeast Ohio Healthcare System, Cleveland, Ohio, USA
| | | | - Paul G Auwaerter
- Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Kelly Baldwin
- Geisinger Medical Center, Danville, Pennsylvania, USA
| | | | - Kiran K Belani
- Childrens Hospital and Clinical of Minnesota, Minneapolis, Minnesota, USA
| | - William R Bowie
- University of British Columbia, Vancouver, British Columbia, Canada
| | - John A Branda
- Massachusetts General Hospital, Boston, Massachusetts, USA
| | - David B Clifford
- Washington University School of Medicine, St. Louis, Missouri, USA
| | | | | | - Peter J Krause
- Yale School of Public Health, New Haven, Connecticut, USA
| | | | | | | | | | | | | | - Amy A Pruitt
- University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Jane Rips
- Consumer Representative, Omaha, Nebraska, USA
| | | | | | | | - Allen C Steere
- Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Franc Strle
- University Medical Centre Ljubljana, Ljubljana, Slovenia
| | - Robert Sundel
- Boston Children's Hospital Boston, Massachusetts, USA
| | - Jean Tsao
- Michigan State University, East Lansing, Michigan, USA
| | | | | | - Lawrence S Zemel
- Connecticut Children's Medical Center, Hartford, Connecticut, USA
| |
Collapse
|
10
|
Koloski CW, Duncan CAM, Rutherford PL, Cassone BJ. Natural insensitivity and the effects of concentration on the repellency and survival of American dog ticks (Dermacentor variabilis) by DEET. EXPERIMENTAL & APPLIED ACAROLOGY 2020; 82:379-395. [PMID: 33009647 DOI: 10.1007/s10493-020-00550-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Accepted: 09/18/2020] [Indexed: 06/11/2023]
Abstract
N,N-Diethyl-m-toluamide (DEET) is by far the most used repellent worldwide. When applied topically to the skin, the active ingredient has been shown to provide protection from a variety of hematophagous insects, including mosquitoes and flies. DEET's effectiveness against ticks is influenced by a variety of factors (e.g., duration and concentration of application, drying time, route of exposure, tick species and developmental stage), and may differ from insects due to their unique chemosensory system that primarily involves the Haller's organ. We therefore used several approaches to investigate DEET's efficacy to repel Dermacentor variabilis at different concentrations (5, 30 or 75%), as well as explore its toxicological properties and natural variability in DEET insensitivity across populations from Manitoba, Canada. Climbing bioassays indicated that higher concentrations of DEET were more effective at repelling D. variabilis, and that ticks from some sampling localities were more sensitive to lower concentrations than others. Petri dish arena assays revealed ticks exposed to high concentrations of the repellent lose their ability to discriminate lower concentrations, perhaps due to overstimulation or habituation. Finally, our tactile assays demonstrated reduced tick survival after contact with high DEET concentrations, with mortality occurring more rapidly with increased concentration. Dermacentor variabilis from these tactile assays displayed a multitude of physiological and neurological symptoms, such as 'hot foot' and various bodily secretions. Overall, our study shows a strong association between repellency, concentration and the acaricidal effects of DEET on D. variabilis.
Collapse
Affiliation(s)
- Cody W Koloski
- Department of Biology, Brandon University, Brandon, MB, R78 6A9, Canada
| | - Carlyn A M Duncan
- Department of Biology, Brandon University, Brandon, MB, R78 6A9, Canada
| | | | - Bryan J Cassone
- Department of Biology, Brandon University, Brandon, MB, R78 6A9, Canada.
| |
Collapse
|
11
|
Harrington LC, Foy BD, Bangs MJ. Considerations for Human Blood-Feeding and Arthropod Exposure in Vector Biology Research: An Essential Tool for Investigations and Disease Control. Vector Borne Zoonotic Dis 2020; 20:807-816. [PMID: 32905735 DOI: 10.1089/vbz.2020.2620] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Eventually there may be a broadly acceptable, even perfected, substitute for the human host requirement for direct feeding experiments by arthropods, most notably mosquitoes. However, for now, direct and indirect feeding on human volunteers is an important, if not essential, tool in vector biology research (VBR). This article builds on the foundational publication by Achee et al. (2015) covering considerations for the use of human participants in VBR pursuits. The authors introduced methods involving human participation in VBR, while detailing human-landing collections (catches) as a prime example. Benedict et al. (2018) continued this theme with an overview of human participation and considerations for research that involves release of mosquito vectors into the environment. In this study, we discuss another important aspect of human use in VBR activities: considerations addressing studies that require an arthropod to feed on a live human host. Using mosquito studies as our principal example, in this study, we discuss the tremendous importance and value of this approach to support and allow study of a wide variety of factors and interactions related to our understanding of vector-borne diseases and their control. This includes establishment of laboratory colonies for test populations, characterization of essential nutrients that contribute to mosquito fitness, characterization of blood-feeding (biting) behavior and pathogen transmission, parameterization for modeling transmission dynamics, evaluation of human host attraction and/or agents that repel, and the effectiveness of antivector or parasite therapeutic drug studies.
Collapse
Affiliation(s)
| | - Brian D Foy
- Department of Microbiology, Immunology & Pathology, Arthropod-Borne and Infectious Diseases Laboratory Fort Collins, Colorado State University, Fort Collins, Colorado, USA
| | - Michael J Bangs
- Public Health & Malaria Control, PT Freeport Indonesia/International SOS, Kuala Kencana, Indonesia.,Department of Entomology, Faculty of Agriculture, Kasetsart University, Bangkok, Thailand
| |
Collapse
|
12
|
McKinney KL, Wu HM, Tan KR, Gutman JR. Malaria in the pregnant traveler. J Travel Med 2020; 27:taaa074. [PMID: 32419013 PMCID: PMC10956547 DOI: 10.1093/jtm/taaa074] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 04/08/2020] [Accepted: 05/11/2020] [Indexed: 11/13/2022]
Abstract
Pregnant travelers face numerous risks, notably increased susceptibility to or severity of multiple infections, including malaria. Because pregnant women residing in areas non-endemic for malaria are unlikely to have protective immunity, travel to endemic areas poses risk of severe illness and pregnancy complications, such as low birthweight and fetal loss. If travel to malaria-endemic areas cannot be avoided, preventive measures are critical. However, malaria chemoprophylaxis in pregnancy can be challenging, since commonly used regimens have varying levels of safety data and national guidelines differ. Furthermore, although chloroquine and mefloquine have wide acceptance for use in pregnancy, regional malaria resistance and non-pregnancy contraindications limit their use. Mosquito repellents, including N,N-diethyl-m-toluamide (DEET) and permethrin treatment of clothing, are considered safe in pregnancy and important to prevent malaria as well as other arthropod-borne infections such as Zika virus infection. Pregnant travelers at risk for malaria exposure should be advised to seek medical attention immediately if any symptoms of illness, particularly fever, develop.
Collapse
Affiliation(s)
- Kimberly L. McKinney
- Department of Family and Preventive Medicine, Emory University School of Medicine, Atlanta, GA, USA
- Air Force Institute of Technology, Wright-Patterson Air Force Base, OH, USA
| | - Henry M. Wu
- Division of Infectious Diseases, Emory University School of Medicine, Atlanta, GA, USA
| | - Kathrine R. Tan
- Malaria Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention (CDC), Atlanta, GA, USA
| | - Julie R. Gutman
- Malaria Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention (CDC), Atlanta, GA, USA
| |
Collapse
|
13
|
Khan L. Staying Safe This Summer. Pediatr Ann 2020; 49:e285-e289. [PMID: 32674164 DOI: 10.3928/19382359-20200622-01] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The arrival of summer brings more sunshine, more time outside, and more opportunities for recreation and play. Although these activities may look a little different this summer as a result of the coronavirus disease 2019 (COVID-19) pandemic, they also allow us to get outside, interact safely with others, and remain connected to our friends and communities. Along with fun activities and exercise, there also comes a need for heightened awareness of summertime safety. Because so many childhood activities occur during the summer, precautions must be taken to ensure the safety and health of our children. From appropriate sun protection and water safety to insect exposure and recreational precautions, it is important to review key safety points to ensure a happy and healthy season. As the COVID-19 pandemic is still very active, there will also be an added layer of complexity to staying safe this summer, including adapting activities to meet the guidelines of social distancing. This article addresses some of the most common dangers encountered during the summer months and offers protective measures to decrease risk and promote safety. [Pediatr Ann. 2020;49(7):e285-e289.].
Collapse
|
14
|
Shelomi M. Who's afraid of DEET? Fearmongering in papers on botanical repellents. Malar J 2020; 19:146. [PMID: 32268926 PMCID: PMC7140559 DOI: 10.1186/s12936-020-03217-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Accepted: 03/30/2020] [Indexed: 11/22/2022] Open
Abstract
DEET (N,N-Diethyl-meta-toluamide) is considered the gold standard in mosquito repellents, not only for its effectiveness, but also for its safety. DEET has been more extensively studied for safety than any other repellent, and is accepted as completely safe when used correctly (i.e. not consumed or bathed in). Researchers studying botanical repellents, however, often paint DEET as far more toxic than it really is, falsely claiming it is a menace to the public health or even the environment. These claims are unfounded, and often the only evidence given by such publications are references to other publications also studying botanical repellents. Such publications are biased, and may be attacking DEET’s excellent safety record to justify their existence and the need for their research. The inconvenient yet undisputable fact is that no botanical repellent has been proven to be as safe as DEET, and the majority never had any safety testing whatsoever. The automatic assumption that botanical repellents are safer than DEET is the ‘appeal to nature fallacy,’ which also drives most of the market for “natural” repellents, yet natural repellents have side effects and even a body count. Finding a botanical repellent that works as well as DEET and is equally safe is a legitimate research goal on its own, and need not be justified by fear-mongering and irrational chemophobia. Researchers studying these alternatives should strive for integrity, raising the real issue of the lack of safety testing for botanical repellents rather than denying the proven safety of DEET.
Collapse
Affiliation(s)
- Matan Shelomi
- Department of Entomology, National Taiwan University, Taipei, Taiwan.
| |
Collapse
|
15
|
Alfhili MA, Nkany MB, Weidner DA, Lee MH. Stimulation of eryptosis by broad-spectrum insect repellent N,N-Diethyl-3-methylbenzamide (DEET). Toxicol Appl Pharmacol 2019; 370:36-43. [DOI: 10.1016/j.taap.2019.03.011] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Revised: 03/05/2019] [Accepted: 03/12/2019] [Indexed: 01/14/2023]
|
16
|
Vassena CV, Cáceres M, Santo-Orihuela PL. Pyrethroid Resistance Associated With a Decreased DEET Repellency in the Common Bed Bug (Hemiptera: Cimicidae). JOURNAL OF ECONOMIC ENTOMOLOGY 2019; 112:997-1000. [PMID: 30566684 DOI: 10.1093/jee/toy387] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Indexed: 06/09/2023]
Abstract
The global resurgence of the bed bug (Cimex lectularius L.) and the widespread resistance of this insect to pyrethroid insecticides have created the need to find alternatives to chemical control. Thus, synthetic or natural repellents have been considered as a suitable choice to control bed bug infestations. Repellents not only keep insects away from their hosts, but also allow a decrease in insecticide selection pressure. The aim of this study was to evaluate the repellence effectivity of DEET against two bed bug colonies from Argentina (a susceptible one and a field-collected pyrethroid-resistant one), under two starving periods. We found different repellent effects of DEET on the two C. lectularius colonies and no differences between the two starving periods. In fact, DEET had a lower effect on the insecticide-resistant colony. The methodology used in this study proved to be useful to test the variation of the effect of DEET between pyrethroid-susceptible and -resistant bed bugs.
Collapse
Affiliation(s)
- Claudia V Vassena
- Centro de Investigaciones de Plagas e Insecticidas (CIPEIN)-UNIDEF-CITEDEF-CONICET, San Juan Bautista de La Salle, Villa Martelli, Provincia de Buenos Aires, Argentina
- Instituto de Ingeniería e Investigaciones Ambientales 3IA - Universidad Nacional de San Martín, San Martín, Provincia de Buenos Aires, Argentina
| | - Mariano Cáceres
- Centro de Investigaciones de Plagas e Insecticidas (CIPEIN)-UNIDEF-CITEDEF-CONICET, San Juan Bautista de La Salle, Villa Martelli, Provincia de Buenos Aires, Argentina
- Instituto de Ingeniería e Investigaciones Ambientales 3IA - Universidad Nacional de San Martín, San Martín, Provincia de Buenos Aires, Argentina
| | - Pablo L Santo-Orihuela
- Centro de Investigaciones de Plagas e Insecticidas (CIPEIN)-UNIDEF-CITEDEF-CONICET, San Juan Bautista de La Salle, Villa Martelli, Provincia de Buenos Aires, Argentina
- Universidad de Buenos Aires - Cátedra de Química Analítica - Facultad de Farmacia y Bioquímica, Junín, Ciudad Autónoma de Buenos Aires, Argentina
| |
Collapse
|
17
|
Reichert W, Ejercito J, Guda T, Dong X, Wu Q, Ray A, Simon JE. Repellency Assessment of Nepeta cataria Essential Oils and Isolated Nepetalactones on Aedes aegypti. Sci Rep 2019; 9:1524. [PMID: 30728370 PMCID: PMC6365536 DOI: 10.1038/s41598-018-36814-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Accepted: 11/20/2018] [Indexed: 12/29/2022] Open
Abstract
There is an increased need for improved and affordable insect repellents to reduce transmission of rapidly spreading diseases with high mortality rates. Natural products are often used when DEET cannot be afforded or accessed and when consumers choose not to use a synthetic repellent. The essential oils from two newly bred Nepeta cataria (catnip) plants representing two different chemotypes and their respective isolated nepetalactone isomers were evaluated as mosquito repellents against Aedes aegypti mosquitoes that transmit the Zika and Dengue virus in a one choice landing rate inhibition assay. A dose response curve was generated for each treatment and a time course analysis of repellency was performed over 24 hours with a N. cataria essential oil sample. The results indicate that all essential oil samples and their respective purified nepetalactone isomers were able to achieve greater than 95% repellency. Between two and four hours, the ability to repel more than 95% of the mosquitoes diminished. At the lowest concentrations tested, the nepetalactones and crude essential oil samples were more effective than DEET at reducing the number of mosquito landings.
Collapse
Affiliation(s)
- William Reichert
- New Use Agriculture and Natural Plant Products Program, Department of Plant Biology, Rutgers University, New Brunswick, New Jersey, USA
| | - Jadrian Ejercito
- Department of Molecular, Cell and Systems Biology, University of California Riverside, Riverside, California, USA
| | - Tom Guda
- Department of Molecular, Cell and Systems Biology, University of California Riverside, Riverside, California, USA
| | - Xujun Dong
- New Use Agriculture and Natural Plant Products Program, Department of Plant Biology, Rutgers University, New Brunswick, New Jersey, USA.,College of Life Science, Shaanxi Normal University, Xi' an, Shaanxi, China
| | - Qingli Wu
- New Use Agriculture and Natural Plant Products Program, Department of Plant Biology, Rutgers University, New Brunswick, New Jersey, USA.,Department of Medicinal Chemistry, Ernest Mario School of Pharmacy, Rutgers University, Piscataway, New Jersey, USA
| | - Anandasankar Ray
- Department of Molecular, Cell and Systems Biology, University of California Riverside, Riverside, California, USA
| | - James E Simon
- New Use Agriculture and Natural Plant Products Program, Department of Plant Biology, Rutgers University, New Brunswick, New Jersey, USA. .,Department of Medicinal Chemistry, Ernest Mario School of Pharmacy, Rutgers University, Piscataway, New Jersey, USA.
| |
Collapse
|
18
|
Hasler T, Fehr J, Held U, Schlagenhauf P. Use of repellents by travellers: A randomised, quantitative analysis of applied dosage and an evaluation of knowledge, Attitudes and Practices (KAP). Travel Med Infect Dis 2018; 28:27-33. [PMID: 30578847 DOI: 10.1016/j.tmaid.2018.12.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 11/14/2018] [Accepted: 12/18/2018] [Indexed: 02/06/2023]
Abstract
BACKGROUND Prevention of arthropod-borne infections hinges on bite prevention. We aimed to investigate travellers' use of repellents. METHODS We measured the amount of applied repellent with a spray containing 30% DEET and 20% Icaridin versus a lotion with 20% Icaridin alone. We calculated the concentration of active ingredient reached on the skin and evaluated formulation acceptability. The travellers completed a questionnaire evaluating Knowledge, Attitudes and Practice (KAP) to anti-vectorial protective measures (AVPM). RESULTS Some 200 volunteers travelling to mosquito borne infection endemic areas were recruited. The mean concentration of active substance achieved on the skin of the left arm was 0.52 mg/cm2 of DEET/Icaridin spray versus 0.21 mg/cm2 of Icaridin lotion. These levels are below the recommended protective dose (1 mg/cm2) for each formulation. Women were significantly more likely to apply a higher, protective dose of repellent. Travellers to Africa, women and older participants showed higher projected adherence to AVPM. CONCLUSIONS Only 2.5% of recruited travellers applied the recommended protective dose of repellent. Women and older travellers are the most adherent users of repellents. The pre-travel health consultation should provide more information on the application quantity and correct use of repellents.
Collapse
Affiliation(s)
- Thomas Hasler
- University of Zurich Centre for Travel Medicine, WHO Collaborating for Travellers' Health, Department of Public Health, Institute for Epidemiology, Biostatistics and Prevention, Hirschengraben 84, 8001, Zurich, Switzerland
| | - Jan Fehr
- University of Zurich Centre for Travel Medicine, WHO Collaborating for Travellers' Health, Department of Public Health, Institute for Epidemiology, Biostatistics and Prevention, Hirschengraben 84, 8001, Zurich, Switzerland; Division of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Ulrike Held
- Department of Biostatistics, Institute for Epidemiology, Biostatistics and Prevention, University of Zurich, Zurich, Switzerland
| | - Patricia Schlagenhauf
- University of Zurich Centre for Travel Medicine, WHO Collaborating for Travellers' Health, Department of Public Health, Institute for Epidemiology, Biostatistics and Prevention, Hirschengraben 84, 8001, Zurich, Switzerland.
| |
Collapse
|
19
|
Segal TR, Mínguez-Alarcón L, Chiu YH, Williams PL, Nassan FL, Dadd R, Ospina M, Calafat AM, Hauser R. Urinary concentrations of 3-(diethylcarbamoyl)benzoic acid (DCBA), a major metabolite of N,N-diethyl-m-toluamide (DEET) and semen parameters among men attending a fertility center. Hum Reprod 2018; 32:2532-2539. [PMID: 29077936 DOI: 10.1093/humrep/dex327] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Accepted: 10/09/2017] [Indexed: 11/13/2022] Open
Abstract
STUDY QUESTION Are specific gravity (SG)-adjusted urinary concentrations of 3-(diethylcarbamoyl)benzoic acid (DCBA) associated with semen parameters among men attending an academic fertility center? SUMMARY ANSWER Our study did not demonstrate any association between SG-adjusted urinary DCBA concentrations and semen parameters among men attending an academic fertility center. WHAT IS KNOWN ALREADY N,N-Diethyl-m-toluamide (DEET) is the most common active ingredient in consumer insect repellents. The recent rise in public health concerns regarding mosquito-borne diseases such as Zika, have led to an increased use of DEET insect repellents, especially among couples planning pregnancy. Animal studies have observed reproductive toxicity from DEET exposure. However, the reproductive health effects of DEET and its metabolites on human reproduction are unknown. STUDY DESIGN, SIZE, DURATION Between 2007 and 2015, 90 men participating in a prospective cohort study at the Massachusetts General Hospital Fertility Center provided 171 urine samples and 250 semen samples for analysis. PARTICIPANTS/MATERIALS, SETTING, METHODS The urinary concentrations of DEET, N,N-diethyl-3-hydroxymethylbenzamide (DHMB) and DCBA were quantified by isotope-dilution tandem mass spectrometry and adjusted by SG. We used linear mixed models to evaluate the association between tertiles of SG-adjusted urinary DCBA concentrations and semen parameters (semen volume, sperm concentration, total sperm count, progressive motility, total progressive motility count, normal morphology and total normal morphology count), adjusting for covariates. DEET and DHMB were not considered for analysis because of the low percentage of detectable concentrations (<7%). Effect modification by BMI and smoking status was explored. MAIN RESULTS AND THE ROLE OF CHANCE Participants had a median age of 36 years and BMI of 27 kg/m2, and 68% had never smoked. The SG-adjusted geometric mean DCBA urinary concentration was 2.20 μg/l, with 85% detection frequency. The majority of semen parameters fell within the normal range with the exception of progressive motility, where 64% of the men had values below the WHO 2010 lower reference limits. SG-adjusted urinary DCBA concentrations were not associated with semen parameters in unadjusted or adjusted models. Men in the highest tertile of SG-adjusted urinary DCBA concentrations had comparable semen parameters to men in the lowest tertile (2.59 vs. 2.88 ml for semen volume, 47.9 vs. 45.8 million/ml for sperm concentration, 116 vs. 118 million for total sperm count, 25 vs. 24% for progressive sperm motility, and 6.1 vs. 5.8% for morphologically normal sperm). In addition, BMI and smoking status did not modify the associations. LIMITATIONS REASONS FOR CAUTION We had a relatively small sample size with similar socioeconomic backgrounds and with overall relatively low urinary concentrations of DEET biomarkers. However, our sample size was enough to detect moderate differences with at least 80% statistical power, between the first and third tertiles of urinary DCBA concentrations. Limitations also include possible misclassification of DCBA exposure and difficulties in extrapolating the findings to the general population. WIDER IMPLICATIONS OF THE FINDINGS Our study found no associations between urinary concentrations of DCBA, a major metabolite of the insect repellent DEET, and semen parameters in men presenting for infertility treatment. While these results are reassuring, further studies including larger sample sizes and higher exposures are warranted. STUDY FUNDING/COMPETING INTEREST(S) The project was financed by the National Institute of Health grants R01ES022955 and R01ES009718 and by grant P30ES000002 from the National Institute of Environmental Health Sciences (NIEHS). None of the authors has any conflicts of interest to declare. The findings and conclusions in this report are those of the authors and do not necessarily represent the official position of the Centers for Disease Control and Prevention. TRIAL REGISTRATION NUMBER N/A.
Collapse
Affiliation(s)
- Thalia R Segal
- Reproductive Endocrinology and Infertility, University Hospitals Cleveland Medical Center and Case Western Reserve University, Cleveland, Oh 44122, USA
| | - Lidia Mínguez-Alarcón
- Department of Environmental Health, Harvard T.H. Chan School of Public Health, 665 Huntington Ave., Boston, MA 02115, USA
| | - Yu-Han Chiu
- Department of Nutrition, Biostatistics, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA
| | - Paige L Williams
- Department of Epidemiology, Biostatistics, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA.,Department of Biostatistics, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA
| | - Feiby L Nassan
- Department of Environmental Health, Harvard T.H. Chan School of Public Health, 665 Huntington Ave., Boston, MA 02115, USA
| | - Ramace Dadd
- Department of Environmental Health, Harvard T.H. Chan School of Public Health, 665 Huntington Ave., Boston, MA 02115, USA
| | - María Ospina
- National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta 30333, Georgia
| | - Antonia M Calafat
- National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta 30333, Georgia
| | - Russ Hauser
- Department of Environmental Health, Harvard T.H. Chan School of Public Health, 665 Huntington Ave., Boston, MA 02115, USA.,Department of Epidemiology, Biostatistics, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA.,Vincent Obstetrics and Gynecology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02115, USA
| | | |
Collapse
|
20
|
Devillers J. 2D and 3D structure-activity modelling of mosquito repellents: a review $. SAR AND QSAR IN ENVIRONMENTAL RESEARCH 2018; 29:693-723. [PMID: 30220218 DOI: 10.1080/1062936x.2018.1513218] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Indexed: 06/08/2023]
Abstract
Repellents disrupt the behaviour of blood-seeking mosquitoes protecting humans against their bites which can transmit serious diseases. Since the mid-1950s, N,N-diethyl-m-toluamide (DEET) is considered as the standard mosquito repellent worldwide. However, DEET presents numerous shortcomings. Faced with the heightening risk of mosquito expansion caused by global climate changes and increasing international exchanges, there is an urgent need for a better repellent than DEET and the very few other commercialised repelling molecules such as picaridin and IR3535. In silico approaches have been used to find new repellents and to provide better insights into their mechanism of action. In this context, the goal of our study was to retrieve from the literature all the papers dealing with qualitative and quantitative structure-activity relationships on mosquito repellents. A critical analysis of the SAR and QSAR models was made focusing on the quality of the biological data, the significance of the molecular descriptors and the validity of the statistical tools used for deriving the models. The predictive power and domain of application of these models were also discussed. The hypotheses to compute homology and pharmacophore models, their interest to find new repellents and to provide insights into the mechanisms of repellency in mosquitoes were analysed. The interest to consider the mosquito olfactory system as the target to compute new repellents was discussed. The potential environmental impact of these chemicals as well as new ways of research were addressed.
Collapse
|
21
|
Colucci B, Müller P. Evaluation of standard field and laboratory methods to compare protection times of the topical repellents PMD and DEET. Sci Rep 2018; 8:12578. [PMID: 30135603 PMCID: PMC6105713 DOI: 10.1038/s41598-018-30998-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Accepted: 08/07/2018] [Indexed: 11/08/2022] Open
Abstract
Mosquitoes are important vectors of pathogens, and travellers to disease endemic countries are advised to avoid bites by applying topical repellents. Topical repellents are typically tested either in the arm-in-cage (AIC) test under laboratory conditions or in the field, but not often under both conditions. We, therefore, investigated how two topical repellents, 15% para-menthane-3,8-diol (PMD) and 15% N,N-diethyl-3-methylbenzamide (DEET) compare against each other both in the AIC test against three species recommended by the World Health Organization (i.e. Aedes aegypti, Anopheles stephensi and Culex quinquefasciatus) and at two field sites in Switzerland, while using the same study participants in all experiments. In the field, the median complete protection time (CPT) was at least 6 hours for both PMD and DEET, while in the AIC test DEET slightly outperformed PMD. CPTs for DEET in the AIC test were 0.5, 2 and 2 hours against Ae. aegypti, An. stephensi and Cx. quinquefasciatus, respectively, and the corresponding median CPTs for PMD were 0.5, 1 and 0.5 hours. In conclusion, DEET slightly outperformed PMD in the AIC test, while the observed landing rates suggest the AIC test to underestimate efficacy of topical repellents in areas with lower landing pressure.
Collapse
Affiliation(s)
- Barbara Colucci
- Epidemiology and Public Health Department, Swiss Tropical and Public Health Institute, Socinstrasse 57, PO Box, CH-4002, Basel, Switzerland
- University of Basel, Petersplatz 1, CH-2003, Basel, Switzerland
| | - Pie Müller
- Epidemiology and Public Health Department, Swiss Tropical and Public Health Institute, Socinstrasse 57, PO Box, CH-4002, Basel, Switzerland.
- University of Basel, Petersplatz 1, CH-2003, Basel, Switzerland.
| |
Collapse
|
22
|
Lo WL, Mok KL, Yu Pui Ming SD. Which insect repellents should we choose? Implications from results of local market survey and review of current guidelines. HONG KONG J EMERG ME 2018. [DOI: 10.1177/1024907918773630] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Mosquito-borne diseases are global problems. The use of topical insect repellents is a key measure recommended by health authorities to prevent mosquito-borne diseases. Despite more than a hundred commercial products available in the market, there are relatively few active ingredients used across these formulations. The most common active components are diethyltoluamide, picaridin, p-menthane-3,8-diol, ethyl butylacetylaminopropionate (IR3535) and a range of plant-derived products. Research has shown that each of these active ingredients vary in the duration of protection provided against biting mosquitoes. However, the wide spectrum of commercial preparations and various recommendations from different health authorities make it a challenge to pick an effective product for end users as well as healthcare personnel. A local market survey was conducted to assess the mosquito repellent formulae in available products in Hong Kong, and a review of the current recommendations issued by local and overseas authorities on choosing the suitable insect repellents is performed with consideration of recent research and currently available topical repellents in the market.
Collapse
Affiliation(s)
- Wai Ling Lo
- Accident and Emergency Department, Ruttonjee Hospital, Wan Chai, Hong Kong
| | - Ka Leung Mok
- Accident and Emergency Department, Ruttonjee Hospital, Wan Chai, Hong Kong
| | | |
Collapse
|
23
|
Magesh A, Sivanesan S, Rajagopalan V, Geetha RV, Roy A. Safety Evaluation of Various Vector Repellents in Combination with Deltamethrin in Wistar Rats. J Pharm Bioallied Sci 2018; 10:21-28. [PMID: 29657504 PMCID: PMC5887648 DOI: 10.4103/jpbs.jpbs_219_17] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Background: Vector repellents are used globally to avoid insect bites and control transmission of diseases. It is important to ensure safety levels of these compounds, although they are noxious to insects. Vector repellents when used in combination are known to bring additional benefits in getting rid of the harmful insects. Unfortunately, the safety levels of various vector repellents such as Deet (N,N-diethyl-m-toluamide), Depa (N,N-diethyl phenylacetamide), and Deb (N,N-diethylbenzamide) are not studied in combination with the widely used pyrethroid deltamethrin (Del). Materials and Methods: In this study, safety evaluation of various vector repellents by oral route in combination with Del was studied by assessing body weight and organ weight changes, hematological parameters, and biochemical parameters in Wistar rats. Results: The results revealed significant changes in liver marker enzymes in Del, Deb, Del + Depa, and Del + Deet groups. Urea levels were significantly altered after treatment with various repellents and in combination with Del, except Deb-alone group. Hematological and rest of the biochemical parameters were found to be unaltered in all the treatment groups. Significant changes in the liver weight were found in Deb, Depa, Deet, Del + Deb, and Del + Deet groups. Conclusions: Taken together, the overall results of this study indicate that single, high oral dose of various insect repellents did not show any additive toxicity.
Collapse
Affiliation(s)
- Anitha Magesh
- Department of Research and Development, Saveetha Institute of Medical and Technical Sciences, Chennai, Tamil Nadu, India
| | - Senthilkumar Sivanesan
- Department of Research and Development, Saveetha Institute of Medical and Technical Sciences, Chennai, Tamil Nadu, India
| | - Vijayaraghavan Rajagopalan
- Department of Research and Development, Saveetha Institute of Medical and Technical Sciences, Chennai, Tamil Nadu, India
| | - Royapuram Veeraragavan Geetha
- Department of Research and Development, Saveetha Institute of Medical and Technical Sciences, Chennai, Tamil Nadu, India
| | - Anitha Roy
- Department of Research and Development, Saveetha Institute of Medical and Technical Sciences, Chennai, Tamil Nadu, India
| |
Collapse
|
24
|
Chang KS, Jeon JH, Kim GH, Jang CW, Jeong SJ, Ju YR, Ahn YJ. Repellency of zerumbone identified in Cyperus rotundus rhizome and other constituents to Blattella germanica. Sci Rep 2017; 7:16643. [PMID: 29192195 PMCID: PMC5709496 DOI: 10.1038/s41598-017-16099-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Accepted: 11/07/2017] [Indexed: 01/09/2023] Open
Abstract
The compounds 1,8-cineole and zerumbone (ZER) from the Cyperus rotundus rhizome along with another 11 previously identified rhizome essential oil constituents and α-humulene, which lacks the only carbonyl group present in ZER, as well as binary mixtures of ZER and seven active compounds were tested for repellency to male B. germanica. The results were compared to N,N-diethyl-3-methylbenzamide (deet). In filter-paper choice tests, ZER was the most repellent compound, and α-humulene was ineffective, which indicates that the α,β-unsaturated carbonyl group of ZER is a prerequisite component for repellency. At 81.5 μg cm−2, enhanced repellency was produced by binary mixtures of ZER and 1,8-cineole, (+)-dihydrocarvone or (R)-(+)-limonene (70:30, 50:50 and 30:70 ratios by weight). These mixtures were very effective against male B. germanica within 24 h and were more repellent than a single compound or deet alone. The optimum ZER content was determined to be more than 50%. In Ebeling choice box tests at 652.4 μg cm−2, these compounds and deet resulted in complete repellency to intact male B. germanica, while they exhibited 35–47% repellency to antennectomized male one. Mixtures formulated from the active constituents of the C. rotundus rhizome could be useful as potential repellents for controlling B. germanica.
Collapse
Affiliation(s)
- Kyu-Sik Chang
- Division of Vectors and Parasitic Diseases, Centers for Disease Control and Prevention, Osong, 28159, Chungbuk, South Korea
| | - Jin-Hwan Jeon
- Division of Vectors and Parasitic Diseases, Centers for Disease Control and Prevention, Osong, 28159, Chungbuk, South Korea
| | - Gi-Hun Kim
- Division of Vectors and Parasitic Diseases, Centers for Disease Control and Prevention, Osong, 28159, Chungbuk, South Korea
| | - Chang-Won Jang
- Division of Vectors and Parasitic Diseases, Centers for Disease Control and Prevention, Osong, 28159, Chungbuk, South Korea
| | - Se-Jin Jeong
- Division of Vectors and Parasitic Diseases, Centers for Disease Control and Prevention, Osong, 28159, Chungbuk, South Korea
| | - Young-Ran Ju
- Division of Vectors and Parasitic Diseases, Centers for Disease Control and Prevention, Osong, 28159, Chungbuk, South Korea
| | - Young-Joon Ahn
- Department of Agricultural Biotechnology, Seoul National University, Seoul, 08826, South Korea.
| |
Collapse
|
25
|
Roy DN, Goswami R, Pal A. The insect repellents: A silent environmental chemical toxicant to the health. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2017; 50:91-102. [PMID: 28171823 DOI: 10.1016/j.etap.2017.01.019] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2016] [Revised: 01/23/2017] [Accepted: 01/26/2017] [Indexed: 05/15/2023]
Abstract
In recent years, a large number of insect repellents have been developed with the idea of consumer benefits. In addition to already known advantageous application of insect repellents, there is increasing concern about the potential toxicity in environment leading to health caused by random use of these compounds. An increasing number of evidence suggests that insect repellents may trigger undesirable hazardous interactions with biological systems with a potential to generate harmful effects including intermediate metabolites. Biotransformation followed by bioaccumulation (vice e versa) may be an important phenomenon for toxic response of this chemicals. In this review, we have summarized the current state of knowledge on the insect repellent toxicity, including biochemical pathway alteration under in vitro and in vivo conditions considering different classes of organisms, from lower to higher vertebrate. Furthermore, we have tried to incorporate the effects of insect repellent in light of some clinical reports. We hope this review would provide useful information on potential side effects of uncontrolled use of insect repellents.
Collapse
Affiliation(s)
- Dijendra Nath Roy
- Department of Bio Engineering, National Institute of Technology, Agartala, Tripura, India.
| | - Ritobrata Goswami
- School of Bio Science, Indian Institute of Technology, Kharagpur, West Bengal, India
| | - Ayantika Pal
- Department of Human Physiology, Tripura University, Tripura, India
| |
Collapse
|
26
|
Patel RV, Shaeer KM, Patel P, Garmaza A, Wiangkham K, Franks RB, Pane O, Carris NW. EPA-Registered Repellents for Mosquitoes Transmitting Emerging Viral Disease. Pharmacotherapy 2016; 36:1272-1280. [PMID: 27779781 DOI: 10.1002/phar.1854] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
In many parts of the United States, mosquitoes were previously nuisance pests. However, they now represent a potential threat in the spread of viral diseases. The Aedes aegypti, Aedes albopictus, and Culex species mosquitoes are endemic to the United States and together may transmit a variety of viral diseases of growing concern, including West Nile virus, chikungunya, dengue fever, and Zika virus. The Centers for Disease Control and Prevention and the Environmental Protection Agency (EPA) recommend N,N-diethyl-meta-toluamide (DEET) as a first-line mosquito repellent, but for patients refusing to use DEET or other conventional repellents, guidance is limited to any EPA-registered product. Therefore, we conducted a systematic review of the literature to identify which EPA-registered personal mosquito repellent provides the best protection from A. aegypti, A. albopictus, and Culex spp. mosquitoes. We abstracted data from 62 published reports of EPA-registered mosquito repellents. The conventional repellent picaridin has the strongest data to support its use as a second-line agent, while IR3535 and oil of lemon eucalyptus are reasonably effective natural products. Citronella, catnip, and 2-undecanone offer limited protection or have limited data. These results can be used by pharmacists and other health care professionals to advise patients on the selection of an EPA-registered mosquito repellent. Regardless of the repellent chosen, it is vital for patients to follow all instructions/precautions in the product labeling to ensure safe and effective use.
Collapse
Affiliation(s)
- Radha V Patel
- Department of Pharmacotherapeutics and Clinical Research, University of South Florida College of Pharmacy, Tampa, Florida.,Department of Internal Medicine, University of South Florida Morsani College of Medicine, Tampa, Florida
| | - Kristy M Shaeer
- Department of Pharmacotherapeutics and Clinical Research, University of South Florida College of Pharmacy, Tampa, Florida.,Department of Internal Medicine, University of South Florida Morsani College of Medicine, Tampa, Florida
| | - Pooja Patel
- Department of Pharmacotherapeutics and Clinical Research, University of South Florida College of Pharmacy, Tampa, Florida.,Department of Family Medicine, University of South Florida Morsani College of Medicine, Tampa, Florida
| | - Aleksey Garmaza
- Department of Pharmacotherapeutics and Clinical Research, University of South Florida College of Pharmacy, Tampa, Florida
| | - Kornwalee Wiangkham
- Department of Pharmacotherapeutics and Clinical Research, University of South Florida College of Pharmacy, Tampa, Florida
| | - Rachel B Franks
- Department of Pharmacotherapeutics and Clinical Research, University of South Florida College of Pharmacy, Tampa, Florida.,Department of Internal Medicine, University of South Florida Morsani College of Medicine, Tampa, Florida
| | - Olivia Pane
- Department of Pharmacotherapeutics and Clinical Research, University of South Florida College of Pharmacy, Tampa, Florida.,Department of Family Medicine, University of South Florida Morsani College of Medicine, Tampa, Florida
| | - Nicholas W Carris
- Department of Pharmacotherapeutics and Clinical Research, University of South Florida College of Pharmacy, Tampa, Florida.,Department of Family Medicine, University of South Florida Morsani College of Medicine, Tampa, Florida
| |
Collapse
|
27
|
Borkakoty B, Jakharia A, Biswas D, Mahanta J. Co-infection of scrub typhus and leptospirosis in patients with pyrexia of unknown origin in Longding district of Arunachal Pradesh in 2013. Indian J Med Microbiol 2016; 34:88-91. [PMID: 26776126 DOI: 10.4103/0255-0857.174116] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND Scrub typhus and leptospirosis are bacterial zoonotic disease causing high morbidity and mortality. The seasonal outbreak of pyrexia is common in Arunachal Pradesh (AP); many times the disease remains undiagnosed. OBJECTIVE An outbreak of pyrexia of unknown origin (PUO) occurred in Longding district of Arunachal Pradesh in 2013, with 108 deaths, which was investigated to elucidate the cause of illness. METHODOLOGY Blood samples from the affected region with acute pyrexia were collected, and screened for the malaria parasite, scrub typhus IgM and leptospira IgM. RESULTS Scrub typhus IgM was reactive in 97% (30/31), and 25% (8/31) cases were co-infected with leptospira. Incidentally, scrub typhus reactive (67%) and leptospira co-infection (62.7%) were higher in females. Record of previous 3 years (2011-2013) from Longding, Community Health Centre showed an increase in indoor pyrexia cases by 2-fold or more during October and November. CONCLUSION The present study is the first report of co-infection of scrub typhus with leptospirosis from Northeast India. Medical officers in this region should take scrub typhus and leptospirosis in their differential diagnosis of patients with PUO for early diagnosis and effective treatment.
Collapse
Affiliation(s)
| | | | - Dipankar Biswas
- Department of Microbiology, Regional Medical Research Center, NE-Region, Dibrugarh, Assam, India
| | | |
Collapse
|
28
|
Tisgratog R, Kongmee M, Sanguanpong U, Prabaripai A, Bangs MJ, Chareonviriyaphap T. Evaluation of a Noncontact, Alternative Mosquito Repellent Assay System. JOURNAL OF THE AMERICAN MOSQUITO CONTROL ASSOCIATION 2016; 32:177-184. [PMID: 27802399 DOI: 10.2987/16-6567.1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
A novel noncontact repellency assay system (NCRAS) was designed and evaluated as a possible alternative method for testing compounds that repel or inhibit mosquitoes from blood feeding. Deet and Aedes aegypti were used in a controlled laboratory setting. Using 2 study designs, a highly significant difference were seen between deet-treated and untreated skin placed behind the protective screens, indicating that deet was detected and was acting as a deterrence to mosquito landing and probing behavior. However, a 2nd study showed significant differences between protected (behind a metal screen barrier) and unprotected (exposed) deet-treated forearms, indicating the screen mesh might restrict the detection of deet and thus influences landing/biting response. These findings indicate the prototype NCRAS shows good promise but requires further evaluation and possible modification in design and testing protocol to achieve more desirable operational attributes in comparison with direct skin-contact repellency mosquito assays.
Collapse
|
29
|
|
30
|
Mitchell RD, Dhammi A, Wallace A, Hodgson E, Roe RM. Impact of Environmental Chemicals on the Transcriptome of Primary Human Hepatocytes: Potential for Health Effects. J Biochem Mol Toxicol 2016; 30:375-95. [PMID: 27091632 DOI: 10.1002/jbt.21801] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2015] [Revised: 02/19/2016] [Accepted: 02/25/2016] [Indexed: 12/22/2022]
Abstract
New paradigms for human health risk assessment of environmental chemicals emphasize the use of molecular methods and human-derived cell lines. In this study, we examined the effects of the insect repellent DEET (N,N-diethyl-m-toluamide) and the phenylpyrazole insecticide fipronil (fluocyanobenpyrazole) on transcript levels in primary human hepatocytes. These chemicals were tested individually and as a mixture. RNA-Seq showed that 100 μM DEET significantly increased transcript levels (α = 0.05) for 108 genes and lowered transcript levels for 64 genes and fipronil at 10 μM increased the levels of 2246 transcripts and decreased the levels for 1428 transcripts. Fipronil was 21-times more effective than DEET in eliciting changes, even though the treatment concentration was 10-fold lower for fipronil versus DEET. The mixture of DEET and fipronil produced a more than additive effect (levels increased for 3017 transcripts and decreased for 2087 transcripts). The transcripts affected for all chemical treatments were classified by GO analysis and mapped to chromosomes. The overall treatment responses, specific pathways, and individual transcripts affected were discussed at different levels of fold-change. Changes found in transcript levels in response to treatments will require further research to understand their importance in overall cellular, organ, and organismic function.
Collapse
Affiliation(s)
- Robert D Mitchell
- Department of Entomology, Toxicology Program, Department of Biology, North Carolina State University, Raleigh, NC, 27695, USA
| | - Anirudh Dhammi
- Department of Entomology, North Carolina State University, Raleigh, NC, 27695, USA
| | - Andrew Wallace
- Toxicology Program, Department of Biology, North Carolina State University, Raleigh, NC, 27695, USA
| | - Ernest Hodgson
- Department of Applied Ecology, Toxicology Program, Department of Biology, North Carolina State University, Raleigh, NC, 27695, USA
| | - R Michael Roe
- Department of Entomology, Toxicology Program, Department of Biology, North Carolina State University, Raleigh, NC, 27695, USA.
| |
Collapse
|
31
|
Alpern JD, Dunlop SJ, Dolan BJ, Stauffer WM, Boulware DR. Personal Protection Measures Against Mosquitoes, Ticks, and Other Arthropods. Med Clin North Am 2016; 100:303-16. [PMID: 26900115 DOI: 10.1016/j.mcna.2015.08.019] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Arthropod-associated diseases are a major cause of morbidity among travelers. Obtaining a detailed travel itinerary and understanding traveler-specific and destination-specific risk factors can help mitigate the risk of vector-borne diseases. DEET, picaridin, PMD, and IR3535 are insect repellents that offer sufficient protection against arthropod bites. IR3535 does not provide adequate protection against Anopheles mosquitoes, and should be avoided in malaria-endemic regions. General protective measures, such as bite avoidance, protective clothing, insecticide-treated bed nets, and insecticide-treated clothing, should be recommended, especially in malaria-endemic areas. Spatial repellents may prevent nuisance biting, but have not been shown to prevent against vector-borne disease.
Collapse
Affiliation(s)
- Jonathan D Alpern
- Division of Infectious Disease & International Medicine, University of Minnesota, 420 Delaware Street SE, MMC 250 Mayo, Minneapolis, MN 55455, USA.
| | - Stephen J Dunlop
- Department of Emergency Medicine, Hennepin County Medical Center, University of Minnesota, 701 Park Avenue, Minneapolis, MN 55415, USA
| | - Benjamin J Dolan
- Department of Emergency Medicine, Hennepin County Medical Center, 701 Park Avenue, Minneapolis, MN 55415, USA
| | - William M Stauffer
- Division of Infectious Diseases & International Medicine, Department of Medicine, University of Minnesota, 420 Delaware Street Southeast, 133 Variety Club Research Center, MMC 284, Minneapolis, MN 55455, USA
| | - David R Boulware
- Infectious Disease & International Medicine, Department of Medicine, University of Minnesota, MTRF 3-222, 2001 6th Street Southeast, Minneapolis, MN 55455, USA
| |
Collapse
|
32
|
Behrens RH. The Raised Potential for Vector-Borne Diseases in European Travelers Following the EU's Biocide Directive on DEET Dosing. J Travel Med 2015; 22:203-5. [PMID: 25728738 DOI: 10.1111/jtm.12191] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/13/2014] [Revised: 01/19/2015] [Accepted: 01/23/2015] [Indexed: 11/28/2022]
Affiliation(s)
- Ron H Behrens
- Department of Travel Medicine, Hospital for Tropical Diseases, London, UK; Department of Clinical Research, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
| |
Collapse
|
33
|
DeGennaro M. The mysterious multi-modal repellency of DEET. Fly (Austin) 2015; 9:45-51. [PMID: 26252744 PMCID: PMC4594586 DOI: 10.1080/19336934.2015.1079360] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Revised: 07/03/2015] [Accepted: 07/20/2015] [Indexed: 01/01/2023] Open
Abstract
DEET is the most effective insect repellent available and has been widely used for more than half a century. Here, I review what is known about the olfactory and contact mechanisms of DEET repellency. For mosquitoes, DEET has at least two molecular targets: Odorant Receptors (ORs) mediate the effect of DEET at a distance, while unknown chemoreceptors mediate repellency upon contact. Additionally, the ionotropic receptor Ir40a has recently been identified as a putative DEET chemosensor in Drosophila. The mechanism of how DEET manipulates these molecular targets to induce insect avoidance in the vapor phase is also contested. Two hypotheses are the most likely: DEET activates an innate olfactory neural circuit leading to avoidance of hosts (smell and avoid hypothesis) or DEET has no behavioral effect on its own, but instead acts cooperatively with host odors to drive repellency (confusant hypothesis). Resolving this mystery will inform the search for a new generation of insect repellents.
Collapse
Affiliation(s)
- Matthew DeGennaro
- Biomolecular Sciences Institute & Department of Biological Sciences; Florida International University; Miami, FL USA
| |
Collapse
|
34
|
Indoor residual spraying with microencapsulated DEET repellent (N, N-diethyl-m-toluamide) for control of Anopheles arabiensis and Culex quinquefasciatus. Parasit Vectors 2014; 7:446. [PMID: 25249021 PMCID: PMC4261282 DOI: 10.1186/1756-3305-7-446] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2014] [Accepted: 09/16/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Evolution of insecticide resistance in Anopheles gambiae complex necessitates evaluation of alternative chemical classes to complement existing insecticides for long lasting insecticidal nets (LLIN) and indoor residual spraying (IRS). Microencapsulated (MC) DEET (N, N-diethyl-m-toluamide) is a formulation of the popular repellent, which gives long lasting activity when applied to nets. Its suitability for IRS use has not been evaluated before. This study assessed the efficacy of DEET MC, for IRS in experimental huts. METHODS DEET MC was tested alongside standard repellent and non-repellent residual insecticides: lambdacyhalothrin, permethrin, pirimiphos methyl and DDT. Residual formulations of these compounds were sprayed on plywood panels attached to walls of experimental huts to assess efficacy against pyrethroid resistant, wild free-flying Anopheles arabiensis and Culex quinquefasciatus. The panel treatments were rotated weekly between huts. RESULTS The overall mortalities of An. arabiensis induced by the various treatments (range: 76-86%) were significantly greater than mortality in the untreated control (8%, P < 0.001). Mortality of An. arabiensis in DEET sprayed huts (82%) was higher than in lambdacyhalothrin CS (76%, P = 0.043) but not significantly different to pirimiphos methyl CS (86%, P = 0.204) or DDT huts (81%, P = 0.703). Against Cx. quinquefasciatus DEET MC was less effective, inducing lower mortality (29%) than other treatments. An arabiensis blood feeding rates were higher in the unsprayed control (34%) than in sprayed huts (range between treatments: 19-22%, P < 0.002), and DEET provided equivalent or superior blood feeding inhibition (44%) to other insecticides. Against Cx. quinquefasciatus there was no significant reduction in blood-feeding for any treatment relative to the control. There was a significantly higher exiting of An. arabiensis from huts sprayed with DEET (98%), lambdacyhalothrin (98%) and permethrin (96%) relative to the control (80%, P < 0.01). Exiting rates of Cx. quinquefasciatus did not differ between treatment huts and the control. CONCLUSION Microencapsulated DEET acts like an insecticide at ambient temperature and induces mosquito mortality when applied to walls made from wooden panels. This trial demonstrated the potential of microencapsulated DEET to control An. arabiensis and warrants further studies of residual activity on interior substrates.
Collapse
|