来源：《新科学家》
原文刊登日期：2022年10月18日
本文适合2024考生
Some people may be more attractive to mosquitoes than others due to an acidic byproduct made by skin bacteria. Maria Elena De Obaldia at the Rockefeller University in New York and her colleagues asked eight people to wear sleeves made from nylon for 6 hours.
由于皮肤细菌产生的酸性副产物，有些人可能比其他人更容易吸引蚊子。纽约洛克菲勒大学的玛丽亚·埃琳娜·德奥巴迪亚和她的同事们让8个人穿上尼龙制成的袖子6小时。
In a series of experiments, nylon swatches worn by each individual were placed in one of two boxes, with the second box containing fabric worn by another of the participants. A third box was attached via a tunnel to the two boxes. This box contained female Aedes aegypti mosquitoes, a major carrier of infections such as yellow fever and Zika.
在一系列实验中，每个人穿过的尼龙布样被放在两个盒子中的一个里，第二个盒子里装的是另一个参与者穿过的布料。第三个盒子通过隧道连接到两个盒子上。这个盒子里装着雌性埃及伊蚊，它是黄热病和寨卡病毒等传染病的主要携带者。
By studying various fabric combinations, the researchers analysed which of the two boxes attracted more mosquitoes. They repeated the experiment over several months to determine if their findings were consistent.
通过研究不同人穿着过的布料组合，研究人员分析了两个盒子中哪一个吸引了更多的蚊子。他们在几个月内重复了这个实验，以确定他们的发现是否始终如一。
The researchers found that nylon worn by people with high levels of carboxylic acids in their body odour was the most attractive to the insects, with these participants being called “mosquito magnets”. Bacteria on the skin produce carboxylic acids as a byproduct of another material produced by skin, called sebum.
研究人员发现，人体气味中羧酸含量高的人所穿的尼龙对蚊子最有吸引力，这些参与者被称为“蚊子磁铁”。皮肤上的细菌产生羧酸，它是皮肤产生的另一种物质——皮脂的副产物。
De Obaldia notes that the team didn’t categorise every chemical in the participants’ body odours, which permeated the nylon. Other skin chemicals and factors such as body temperature and the exhalation of carbon dioxide have also been linked to mosquito-biting behaviour.
德奥巴迪亚指出，研究小组并没有对参与者身体气味中渗透到尼龙中的每一种化学物质进行分类。其他皮肤化学物质和因素，如体温和二氧化碳的排出，也与蚊子叮咬行为有关。
Unfortunately, it may not be possible to change the amount of carboxylic acids we produce in an attempt to avoid being bitten. “Human skin odour may be affected by genetic factors, skin microbiome and our overall diet,” says De Obaldia. “It is unlikely to be caused by short-term factors that are constantly changing, such as what one has for lunch on a particular day.”
不幸的是，我们可能无法为了避免被咬，改变体内羧酸的含量。“人类皮肤的气味可能受到遗传因素、皮肤微生物群和我们的整体饮食的影响，”德奥巴迪亚说。“它不太可能是由不断变化的短期因素造成的，比如某一天的午餐吃什么。”
Skin bacteria play a major role in our body odour. By living deep in the pores, the microbes can’t easily be removed, says De Obaldia. “Even when we wash the skin surface, it is soon repopulated by skin microbes.”
皮肤细菌在我们的体味中扮演着重要角色。德奥巴迪亚说，这些微生物生活在毛孔深处，不容易被清除。“即使我们清洗皮肤表面，皮肤微生物很快就会重新繁殖。”
In a second part of the research, the team repeated the experiment with genetically modified mosquitoes that have a reduced ability to sense acids. A far lower percentage of these mosquitoes were attracted to the nylon, but the insects could still differentiate fabrics belonging to mosquito magnets.
在研究的第二部分，研究小组用基因改造的蚊子重复了实验，这些蚊子对酸的感知能力下降。这些蚊子中被尼龙吸引的比例要低得多，但这些蚊子仍能分辨出属于蚊子磁铁的织物。
“I think this reflects the fact that mosquitoes are choosing who to bite based on several – potentially many – odours emanating from our skin,” says De Obaldia. “It also reflects redundancy in the olfactory system of the mosquito: when one receptor pathway is disrupted, the relevant molecules can still be detected by a different receptor pathway.”
“我认为这反映了一个事实，即蚊子会根据我们皮肤散发的几种——可能是多种——气味来选择叮咬对象，”德奥巴迪亚说。“这也反映了蚊子嗅觉系统的冗余：当一个受体通路被破坏时，相关分子仍然可以被另一个受体通路检测到。”
According to De Obaldia, it is unclear why mosquitoes are attracted to one human over another. “Female mosquitoes can get perfectly good blood protein to support egg development from any human,” she says.
据德奥巴迪亚说，目前还不清楚为什么有些人更吸引蚊子。她说：“雌蚊可以从任何人类身上获得完美的血液蛋白质，以支持卵的发育。”