嗡嗡不絕的蚊子、令人瘙癢的叮咬和噴霧驅(qū)蟲劑,這些都是夏天室外“樂趣”的一部分,對于一些人來說,這是不可避免的。你覺得自己的后背、胳膊和腿上好像有個巨大的靶子,專供蚊子叮咬——你的頭上卻沒有。下文告訴你,你為什么容易被蚊子叮咬,以及應(yīng)該怎么辦。
Why Mosquitoes Prefer Some People Over Others
為什么蚊子更喜歡叮咬某些人
“The phenomenon does exist, and you can demonstrate that scientifically,” James Logan, head of the Department of Disease Control at the London School of Hygiene and Tropical Medicine, said of the insects’ apparent preference for some people. “You can also show that’s due to body odor.”
“這種現(xiàn)象確實存在,可以通過科學(xué)證實,”倫敦衛(wèi)生和熱帶醫(yī)學(xué)院(London School of Hygiene and Tropical Medicine)疾病控制系主任詹姆斯·洛根(James Logan)說,這種昆蟲顯然偏愛某些人群。“還可以看到是因為體味。”
Mosquitoes hunt using all of their senses, but smell is a predominant factor. A higher metabolism, higher body temperature and more sweat make you more likely to be bitten. But a person’s scent is just one element. Mosquitoes are attracted to the lactic acid your body produces, the carbon dioxide you exhale and the natural bacteria that live on your skin.
蚊子獵食的時候會用上所有的感官,但氣味是主要因素。新陳代謝更快、體溫更高、汗水更多的人更有可能被叮咬。但人體的氣味只是其中的元素之一。蚊子還會被身體產(chǎn)生的乳酸、呼出的二氧化碳和皮膚上的天然細(xì)菌所吸引。
“The good news is that these people smell normal, so they smell like a human being,” Professor Logan said. “The bad news is that they will probably always be that level of attractiveness.”
“好消息是,這樣的人聞起來很正常,他們的氣味聞上去就是人類的味道,”洛根說。“壞消息是,對于蚊子來說,這些人可能會一直保持這種程度的吸引力。”
Professor Logan and his team are studying the genetic reasons for this attraction, as well as natural repellents produced by people’s bodies.
洛根及其團隊正在研究這種吸引力的遺傳因素,以及人體所產(chǎn)生的天然驅(qū)蚊劑。
“If we identify the genes that control the production of natural repellents and susceptibility to mosquitoes, we can develop a drug that would keep mosquitoes away rather than putting DEET on,” he said.
“如果我們可以確定那些能決定天然驅(qū)蚊劑的產(chǎn)生,以及對蚊子易感性的基因,就可以開發(fā)一種能讓蚊子遠(yuǎn)離的藥物,不用再噴待乙妥驅(qū)蚊劑了,”他說。
Keep Mosquitoes at Bay Before They Bite
遠(yuǎn)離蚊子的叮咬
The Centers for Disease Control and Prevention recommend using a repellent registered by the Environmental Protection Agency. The most popular and accessible form of E.P.A.-approved repellent is DEET, short for N,N-diethyl-meta-toluamide.
疾病預(yù)防與控制中心(Centers for Disease Control and Prevention)推薦使用經(jīng)國家環(huán)保局(Environmental Protection Agency,簡稱EPA)認(rèn)證的驅(qū)蚊劑。最受歡迎、也最容易買到的EPA認(rèn)證驅(qū)蚊劑是待乙妥(DEET)——“N,N-二乙基間甲苯酰胺”的縮寫。
You shouldn’t be fooled by higher DEET concentrations on repellent bottles, however. Unlike the SPF rating in sunscreens, higher concentrations of DEET don’t mean more protection. Instead, the higher the percentage of DEET in a repellent, the longer it will be effective before you have to reapply.
然而,不要被驅(qū)蚊劑包裝上較高的待乙妥濃度迷惑。和防曬霜的SPF等級不同,濃度更高的待乙妥并不意味著更多的保護。驅(qū)蚊劑中待乙妥含量的百分比較高只是意味著使用效果可以持續(xù)更長。
Janet McAllister, a research entomologist for the C.D.C.’s division of vector-borne diseases in Fort Collins, Colo., recommends visiting the E.P.A.’s repellent-finder website to choose the right one for your needs.
科羅拉多州柯林斯堡的疾控中心媒傳疾病部門昆蟲學(xué)家珍妮特·麥卡利斯特(Janet McAllister)建議使用者訪問EPA的驅(qū)蚊劑網(wǎng)站,根據(jù)自身需要選擇合適的產(chǎn)品。
“If you’re going to be outdoors for eight hours, you might want to try a higher concentration repellent, but if you’re only outdoors gardening for maybe an hour or two, you could use a lower concentration,” Dr. McAllister said.
“如果要到戶外玩八小時,可能需要更高濃度的驅(qū)蚊劑,但如果只是做一兩個小時的戶外園藝,就可以使用濃度較低的產(chǎn)品,”麥卡利斯特說。
And those citronella candles — do they work?
還有香茅蠟燭呢,它們有用嗎?
“No,” Dr. McAllister said, “not unless you’re standing directly over the candle. It’s the smoke that repels them, not the citronella.”
“沒用,”麥卡利斯特說。“除非你直接站在蠟燭上方。驅(qū)散蚊子的是煙霧,而不是香茅的味道。”
“They’re very hard to fool,” she added. “Even if you’re standing next to a mosquito trap, they can still tell a live animal from not.”
“它們很難被騙過去,”她補充說。“即使你站在捕蚊器旁邊,它們?nèi)匀豢梢苑直娉龌钗铩?rdquo;
Leigh Krietsch Boerner, science editor for The Wirecutter and The Sweethome, product review websites owned by The New York Times, recommends a “dry” insect repellent spray with 25 percent DEET.
《紐約時報》旗下的產(chǎn)品測評網(wǎng)站W(wǎng)irecutter和The Sweethome的科學(xué)編輯利·克里奇·伯爾納(Leigh Krietsch Boerner)推薦使用待乙妥含量為25%的一種“干性”驅(qū)蟲噴霧劑。
“We don’t recommend using higher than 30 percent of DEET for anything,” Ms. Boerner said. She and The Sweethome team tested how different repellents dried, smelled and felt on the skin. They applied some to fabric to make sure it dried quickly, didn’t leave residue and didn’t stain clothing.
“我們不建議使用待乙妥含量超過30%的任何產(chǎn)品,”伯爾納說。她和The Sweethome的團隊測試了不同種類驅(qū)蚊劑殘留在皮膚上的干燥物,以及它們的氣味和感覺。他們還使用一些服裝面料,測試驅(qū)蟲劑是否會很快干燥、是否有殘留物,是否會給衣服染色。
Dry versions typically spray on lightly and contain a small amount of cornstarch, which leaves your skin feeling dry after application and avoids that oily sensation that comes with other repellent sprays. The downside to dry sprays, however, is that cornstarch (or talc, in some sprays) can leave a white powder on clothing, but it can be easily brushed off, Ms. Boerner said.
干性驅(qū)蚊劑通常需要少量噴灑,它含有少量玉米淀粉,使用后令皮膚感覺干爽,沒有其他驅(qū)蚊噴霧劑那種油膩的感覺。干性噴劑的缺點是玉米淀粉(或一些噴劑中的滑石粉)可能在衣服上留下白色粉末,但是伯爾納說那很容易擦掉。
Dr. Mark Fradin, a clinical associate professor of dermatology at the University of North Carolina at Chapel Hill, has studied the efficacy of repellents. He recommends a three-pronged approach to prevention: avoid mosquitoes’ natural habitat, apply repellent to skin and apply repellent to clothing.
北卡羅來納大學(xué)教堂山分校皮膚科臨床副教授馬克·弗雷丁(Mark Fradin)博士研究了驅(qū)蚊劑的功效。他建議采取三管齊下的預(yù)防措施:避免去蚊子的自然棲息地,在皮膚上噴灑驅(qū)蚊劑,并在衣服上也噴灑驅(qū)蚊劑。
Similarly, when you’re applying repellent, don’t skimp. Many people treat it as if it has a “cloaking effect,” and that won’t protect you at all.
而且,使用驅(qū)蚊劑時不要吝嗇。許多人使用驅(qū)蚊劑時就好像它有“斗篷效應(yīng)”一樣,但這樣根本不會保護你。
“A dot behind each ear or on each wrist will not set up a force field,” Dr. Fradin said. “If you skip a one-inch swath, they’ll find it.”
“在耳朵后面或者手腕上噴灑一點,這樣并不會建立一個力場,”弗雷丁說,“只要你漏噴了一英寸的地方,都會被它們找到。”
If you’re uncomfortable using DEET, Dr. Fradin recommends using two other repellents recommended by the C.D.C.: picaridin and lemon eucalyptus oil.
如果使用待乙妥讓你覺得不舒服,弗雷丁建議使用疾控中心推薦的另外兩種驅(qū)蚊劑:派卡瑞丁(picaridin)和檸檬桉葉油。
Treat Bites the Right Way
治療叮咬的正確方式
Even with preparation, you’re likely to get at least a few bites over the course of the summer, especially if you’re more prone to bites than others. When it comes to treatment, Dr. Fradin recommends ice, a low-potency hydrocortisone and simple patience.
即使做足了準(zhǔn)備,整個夏天里也難免被咬上幾口,特別是如果你比別人更容易挨咬的話。在治療方面,弗雷丁推薦使用冰、低效氫化可的松(hydrocortisone)和一點耐心。
“We try to dissuade people from using a topical Benadryl cream because of the risk of sensitivity or reaction,” he said. He also recommends staying away from caladryl and calamine lotions for the same reason. Many turn to them to alleviate itching, but these may be better options for skin irritation from something like poison ivy.
“我們會盡量建議大家不要使用目前的苯海拉明(Benadryl)軟膏,因為有過敏或其他反應(yīng)的風(fēng)險。”出于同樣的原因,他還建議遠(yuǎn)離爐甘石乳液。許多人使用它們來減輕瘙癢,但它們更適合皮膚受到毒藤等物刺激的情況。
“I don’t think caladryl does much for insect bites,” Dr. Fradin said.
“我認(rèn)為爐甘石對蚊蟲叮咬沒有很大作用,”弗雷丁說。
Should you have an intense reaction to a mosquito (or other insect) bite, prescription-strength steroids may be needed, and you should consult your doctor. You should try not to scratch, and instead gently tap the area around the bite to alleviate itching. After that, you just have to wait it out. Dr. Fradin offered one crumb of comfort.
如果你對蚊子或其他昆蟲的叮咬產(chǎn)生了強烈反應(yīng),可能需要處方藥強度的類固醇,并且應(yīng)當(dāng)咨詢醫(yī)生。盡量避免抓撓,只是輕輕點擊叮咬處周圍的區(qū)域以減輕瘙癢。之后,你只需等待瘙癢過去。弗雷丁這里有一個小小的安慰。
“It will eventually stop itching,” he said.
“瘙癢最終總會停止,”他說。