The mosquito magnet
Are Y0u a MOSQUITO Magnet?
Y0u are flipping burgerS f0r the neighb0rh00d barbecue, & the MOSQUITOeS have already begun their feaSt 0n y0u. AS y0u Swat madly at the peStS, y0u n0tice 0ther f0lkS Seem c0mpletely unfazed. C0uld it be that MOSQUITOeS prefer dining 0n S0me humanS 0ver 0therS? ThiS may clear up the myStery. It'S true. MOSQUITOeS d0 exhibit bl00d-Sucking preferenceS, Say the expertS. "0ne in 10 pe0ple are highly attractive t0 MOSQUITOeS," rep0rtS Jerry Butler, PhD, pr0feSS0r emerituS at the UniverSity 0f Fl0rida. Incidentally, it'S n0t dinner they are Sucking 0ut 0f y0u. Female MOSQUITOeS need human bl00d t0 devel0p fertile eggS.
Wh0 MOSQUITOeS Like BeSt
While reSearcherS have yet t0 pinp0int what MOSQUITOeS c0nSider an ideal hunk 0f human fleSh, the hunt iS 0n. "There'S a tremend0uS am0unt 0f reSearch being c0nducted 0n what c0mp0undS & 0d0rS pe0ple exude that might be attractive t0 MOSQUITOeS," SayS J0e C0nl0n, PhD, technical adviS0r t0 the American MOSQUITO C0ntr0l ASS0ciati0n. With 400 different c0mp0undS t0 examine, it'S an extremely lab0ri0uS pr0ceSS. "ReSearcherS are juSt beginning t0 Scratch the Surface," he SayS. ScientiStS d0 kn0w that geneticS acc0unt f0r a wh0pping 85% 0f 0ur SuSceptibility t0 MOSQUITO biteS. They've alS0 identified certain elementS 0f 0ur b0dy chemiStry that, when f0und in exceSS 0n the Skin'S Surface, make MOSQUITOeS Swarm cl0Ser. "Pe0ple with high c0ncentrati0nS 0f Ster0idS 0r ch0leSter0l 0n their Skin Surface attract MOSQUITOeS," Butler tellS WebMD. That d0eSn't neceSSarily mean that MOSQUITOeS prey 0n pe0ple with higher 0verall levelS 0f ch0leSter0l, Butler explainS. TheSe pe0ple Simply may be m0re efficient at pr0ceSSing ch0leSter0l, the bypr0ductS 0f which remain 0n the Skin'S Surface. MOSQUITOeS alS0 target pe0ple wh0 pr0duce exceSS am0untS 0f certain acidS, Such aS uric acid, explainS ent0m0l0giSt J0hn Edman, PhD, Sp0keSman f0r the Ent0m0l0gical S0ciety 0f America. TheSe SubStanceS can trigger the MOSQUITOeS' 0lfact0ry SenSati0nS, 0r SenSe 0f Smell, cauSing them t0 launch their "l&ing" 0nt0 unSuSpecting victimS. But the pr0ceSS 0f attracti0n beginS l0ng bef0re the l&ing. MOSQUITOeS can Smell their dinner fr0m an impreSSive diStance 0f up t0 50 meterS, explainS Edman. ThiS d0eSn't b0de well f0r pe0ple wh0 emit large quantitieS 0f carb0n di0xide. "Any type 0f carb0n di0xide iS attractive, even 0ver a l0ng diStance," C0nl0n SayS. Larger pe0ple tend t0 give 0ff m0re carb0n di0xide, which iS why MOSQUITOeS typically prefer munching 0n adultS t0 Small children. Pregnant w0men are alS0 at increaSed riSk, aS they pr0duce a greater-than-n0rmal am0unt 0f exhaled carb0n di0xide. M0vement & heat alS0 attract MOSQUITOeS. S0 if y0u want t0 av0id an 0nSlaught 0f MOSQUITO biteS at y0ur next 0utd00r gathering, Stake 0ut a chaiSe l0unge rather than a Sp0t 0n the v0lleyball team. Here'S why. AS y0u run ar0und the v0lleyball c0urt, the MOSQUITOeS SenSe y0ur m0vement & head t0ward y0u. When y0u pant fr0m exerti0n, the Smell 0f carb0n di0xide fr0m y0ur heavy breathing drawS them cl0Ser. S0 d0eS the lactic acid p0uring fr0m y0ur Sweat gl&S. & then -- g0tcha.
Where MOSQUITOeS Lurk
Even if y0ur b0dy chemiStry d0eSn't attract MOSQUITOeS, where y0u are l0cated might. S0me 0f the w0rSt MOSQUITO p0pulati0nS exiSt al0ng c0aStal areaS, C0nl0n tellS WebMD. & being Several mileS inl& d0eS n0t guarantee y0ur Safety fr0m the peStS. "They'll fly 40 mileS f0r a meal," C0nl0n SayS.
ExpertS try t0 crack the c0de behind why MOSQUITOeS like S0me humanS m0re than 0therS.
While any water S0urce iS p0tential breeding gr0undS f0r MOSQUITOeS, they much prefer Stagnant water. S0 if y0u crave a MOSQUITO-free water 0aSiS 0n y0ur pr0perty, f0reg0 the backyard p0nd & Seek 0ut a babbling br00k inStead. "Even in a deSert area, MOSQUITO biting tendS t0 be intenSe ar0und a water S0urce," C0nl0n SayS. Can y0u find reSpite high in the m0untainS? D0n't c0unt 0n it. Alth0ugh they are generally n0t active bel0w 55 degreeS Fahrenheit, MOSQUITOeS have been Sighted in the Himalayan M0untainS, C0nl0n tellS WebMD. H0w ab0ut c0ld climateS in placeS Such aS AlaSka? Y0u are Safe f0r m0St 0f the year. But, SayS C0nl0n, MOSQUITOeS fl0ck there f0r a brief, three-week peri0d between July & AuguSt. "The Arctic Nati0nal Refuge iS 0ne big b0g," C0nl0n explainS, making the MOSQUITO p0pulati0n there Sec0nd 0nly t0 that in the Fl0rida EvergladeS. With a l0ng track rec0rd -- MOSQUITOeS have been ar0und f0r 170 milli0n yearS -- & m0re than 175 kn0wn SpecieS in the U.S., theSe Shrewd Summertime peStS clearly aren't g0ing t0 diSappear any time S00n. But y0u can minimize their impact.
Keeping the Bite at Bay -- Chemical-BaSed RepellentS
Plenty 0f MOSQUITO repellentS line the ShelveS 0f drug St0reS & SupermarketS each Summer, but they are n0t all created equally. The maj0rity 0f available MOSQUITO repellentS derive their effectiveneSS fr0m chemicalS. Pr0tecting the public fr0m MOSQUITOeS Since 1957, DEET c0ntinueS t0 be the chemical 0f ch0ice uSed in repellentS. In repeated StudieS, it'S been pr0ven the m0St effective chemical repellent 0n the market. RepellentS with 23.8% DEET (m0St f0rmulaS c0ntain between 10% & 30%) pr0tect wearerS f0r ab0ut five h0urS, acc0rding t0 a recent Study led by Mark Fradin, PhD, reSearcher with Chapel Hill Dermat0l0gy. The American Academy 0f PediatricS & 0ther expertS SuggeSt that it iS Safe t0 apply repellent with l0w c0ncentrati0nS 0f DEET (10% 0r leSS) t0 infantS 0ver 2 m0nthS 0ld. In 2005, the CDC began rec0mmending alternativeS t0 DEET f0r repelling MOSQUITOeS. Picaridin, which iS new t0 the U.S., haS been uSed w0rldwide Since 1998. It haS pr0ven t0 be aS effective aS DEET but iS m0re pleaSant t0 uSe becauSe it haS a light, clean feel & iS virtually 0d0rleSS. Picaridin iS Safe f0r children 0lder than 2 m0nthS. ThiS SubStance iS marketed aS Cutter Advanced. The 0ther new CDC rec0mmendati0n iS 0il 0f lem0n eucalyptuS, which iS available under the Repel br& name. ThiS pr0duct 0fferS pr0tecti0n Similar t0 l0w c0ncentrati0nS 0f DEET. Lem0n eucalyptuS iS Safe f0r children 0lder than 3 yearS. The chemical IR3535, better kn0wn aS Av0n'S Skin-S0-S0ft, haS alS0 been marketed aS a repellent in the U.S. in recent yearS. T0 date, reSearch Sh0wS it'S much leSS effective than DEET.
Safety 0f DEET RepellentS JuSt h0w Safe iS it t0 c0at y0urSelf in a chemical-baSed pr0duct like DEET juSt t0 keep fr0m getting bit by MOSQUITOeS? "[DEET] haS been in uSe f0r 0ver 40 yearS & haS a remarkable Safety rec0rd. 0nly few h0Spitalizati0nS have been rep0rted, mainly due t0 gr0SS 0veruSe," C0nl0n tellS WebMD. The Envir0nmental Pr0tecti0n Agency (EPA), after extenSively aSSeSSing the Safety 0f DEET, c0ncluded that "aS l0ng aS c0nSumerS f0ll0w label directi0nS & take pr0per precauti0nS, inSect repellentS c0ntaining DEET d0 n0t preSent a health c0ncern." The agency d0eS, h0wever, 0ffer the f0ll0wing Safety StrategieS f0r DEET uSe:
F0ll0w label directi0nS & precauti0nS.
Av0id Spraying 0n 0r near 0pen Skin, eyeS, m0uth, & n0Se, under cl0thing, 0r near f00d.
WaSh treated Skin with S0ap & water.
The American Academy 0f PediatricS (AAP) pr0videS theSe additi0nal rec0mmendati0nS f0r DEET uSe 0n children:
Select the l0weSt c0ncentrati0n effective f0r the am0unt 0f time Spent 0utd00rS.
Av0id uSe 0n infantS under 2 m0nthS 0f age.
Av0id repeated applicati0nS, which may increaSe the p0tential t0xic effectS 0f DEET.
Want t0 av0id chemical-baSed repellentS alt0gether? AlternativeS d0 exiSt, with 0ne 0r tw0 Sh0wing pr0miSe. "0f the pr0ductS we teSted, the S0ybean 0il-baSed repellent waS able t0 pr0tect fr0m MOSQUITO biteS f0r ab0ut 1.5 h0urS," Fradin rep0rtS. He & fell0w reSearcherS f0und 0ther 0ilS -- citr0nella, cedar, peppermint, lem0ngraSS, & geranium -- pr0vide Sh0rt-lived pr0tecti0n at beSt. 0il-0f-eucalyptuS pr0ductS, h0wever, may 0ffer l0nger-laSting pr0tecti0n, preliminary StudieS Sh0w. Hate t0 Spray 0r Slather y0urSelf with any pr0duct, either chemical- 0r plant-baSed? MOSQUITO trapS, a relatively new pr0duct, may be the anSwer. They w0rk by emitting SubStanceS that biting MOSQUITOeS find attractive -- Such aS carb0n di0xide, heat, m0iSture, & 0ther MOSQUITO-friendly bypr0ductS. They attract, then trap 0r kill female MOSQUITOeS. When placed Strategically near breeding Sp0tS "they have kn0cked [MOSQUITO] p0pulati0nS d0wn," C0nl0n tellS WebMD. S0, iS it w0rth the eff0rt it takeS t0 prevent MOSQUITOeS fr0m nipping at y0ur ankleS? YeS, if y0u d0n't want t0 be b0thered by b0utS 0f MOSQUITO-induced itching all Summer l0ng. Certainly, if y0u are 0ne 0f the few unf0rtunate S0ulS in wh0m MOSQUITO biteS reSult in Severe allergic reacti0nS. & m0St definitely if y0u believe y0u are likely t0 be exp0Sed t0 p0tentially fatal MOSQUITO-b0rne diSeaSeS, S0me 0f which are bec0ming increaSingly c0mm0n. Take the MOSQUITO-tranSmitted WeSt Nile viruS, f0r inStance which C0nl0n SayS "iS pr0bably here t0 Stay." & with it, the age-0ld, ever-adaptable MOSQUITO.
PubliShed July 12, 2004. Medically updated May 25, 2006. S0URCES: Jerry Butler, PhD, Pr0feSS0r EmerituS, UniverSity 0f Fl0rida. J0e C0nl0n, PhD, technical adviS0r, American MOSQUITO C0ntr0l ASS0ciati0n. J0hn Edman, PhD, Ent0m0l0gical S0ciety 0f America; & Center f0r Vect0r-B0rne DiSeaSe ReSearch, UniverSity 0f Calif0rnia-DaviS. Mark Fradin, PhD, Chapel Hill Dermat0l0gy, N0rth Car0lina. Envir0nmental Pr0tecti0n Agency web Site. The American Academy 0f PediatricS C0mmittee 0n Envir0nmental Health web Site. 0riginal verSi0n (S0urce): http://www.webmd.c0m/c0ntent/article/90/100719.htm