Rumors: "! A blood type people we recruit most mosquitoes," "Every time I go out with friends are the most mosquito bites, O-type blood really bad," Do you often hear my friends complained,! they all claim that their blood type most to mosquitoes, but the conclusion is so inconsistent, covering almost all of the blood group (A, B and O).
Truth: summer approaching, mosquitoes, better people fed. Life can really find some people to be more discussions like mosquitoes, like everyone says that because the blood it?

An interesting experiment

Mosquitoes and the blood about it? Scientists really have done this experiment, the research results are also published in the prestigious scientific journal "Nature" above. Experimental procedure was recruited 102 people of different blood types, and then let them into his arms equipped with 20 mosquito sealed box. After 10 minutes, by examining the stomach of the mosquito's blood to determine blood bite circumstances.

100 results found in several experiments to analyze, O blood type is a maximum number of bites, the authors conclude that blood type O may be the most strokes mosquitoes. The author does not know the reason, but presumably due to the decision of the blood and sweat on the skin surface antigen also has distribution, thus creating differences between blood attractive to mosquitoes.

This experiment was completed in the 70s of last century, when the mosquito research is still exploring. This fun and reliable results it? Let us first look at how the mosquito bites in the end decided to target it!

Buzzed, biting who?

It is not difficult to guess, mosquito bites certainly due to what your body guide them to find you, but you must not think of the guidelines could be so many mosquitoes substances. As long as you're breathing, sweating, or emit heat, your temperature, water vapor you release the carbon dioxide, you sweat acetone, octenol, lactic acid and other chemicals, and many are tempted with dozens of mosquitoes, let them find you follow the subtle traces.

In many temptations, the most important when the number of carbon dioxide, which is a major clue mosquitoes find you. Notably attract mosquitoes is not a simple carbon, but the carbon dioxide gas stream, by identifying the direction of air flow, to lock the target mosquito. In field experiments, adding carbon dioxide mosquito traps can no added carbon dioxide than similar mosquito traps to capture 8-45 times more than mosquitoes. Wear masks while giving a fitted soda lime (to neutralize the carbon dioxide exhaled), you can let him dropped significantly the chances of mosquito bites. Although slight differences between the different types of mosquitoes, but basically relying on carbon dioxide they can find you, if the main body odor with other substances, such as lactic acid, acetone and octenol, looking from the target to be easier. It is worth mentioning that there are studies indicate that the principle of many insect repellent products containing DEET (DEET) is the component works by inhibiting the mosquito receptors feel these clues, so that mosquitoes find north.

So one has just finished sweating sports person is a mosquito's favorite, gasping for air exhaled carbon dioxide and sweat chemical substances they have a strong appeal. Some carbon dioxide emissions than more people, such as pregnant women metabolism faster than the average person, but also may be more susceptible to bites than others.

In addition, it was often referred to dark clothes easy to move mosquitoes, is justified. When a mosquito and fly almost found the target after the vision began to work, and even mosquitoes will ultimately fall on the target body has a great influence. Mosquito visual system in a dark environment, the most active, adequate light or too dark are completely non-love it, so the effect of the weaker black reflective of their most attractive. Because of this visual preference, in the daytime, mosquitoes prefer warm and moist black objects, such as the sweat of your body slightly black T-shirt. So I would like to avoid the mosquitoes, then go to the next to avoid such dress Oh!

Some basic research on mosquitoes in the 1990s has been broadly understood, may be mentioned so many factors that attract mosquitoes in textbooks, but did not mention the role of play in which any blood. Perhaps the main reason is the current study can not draw definitive conclusions.

Mosquitoes suck blood? Divergent views

Let us return to the interesting experiments on it. Scientists call this experiment Wood, an expert study of malaria. In 1972 she was presented with a blood-related mosquito bites this novel idea [1], the design of the experiment and gives a hypothesis to explain blood group antigens. It now appears that this experiment a bit shabby, statistical experimental design and data analysis are not considered and ruled out interference from other factors, but the innovative spirit is commendable.

Thereafter, Wood and improve her experiments, observations of the mosquitoes landing (landing) and vampire (blood meal) were distinguished (as mosquitoes landed on the skin does not necessarily vampire), and further examines the color, moisture, skin temperature [4], the same blood and non-secreted secretion [5] (secreted, the blood group antigens are secreted in sweat, saliva and other body fluids of the human; non-secreting type, the sweat, saliva and other body fluids does not contain blood group antigen people if because sweat blood group antigens attractive to mosquitoes do have differences on, then secreted between different blood types, secreted and non-secreted between attract mosquitoes should exhibit the degree of Effect of different.) and other factors. The result is skin color, moisture, skin temperature does not affect the number of mosquito bites, and secretion of type O blood type O blood than non-secretory, A-type blood secreted by the mosquitoes are more favored, consistent with the hypothesis.

But, these experiments have not taken into account, such as sweat, carbon dioxide such important variables. Such deficiencies are well supplemented Thornton experiments.

Thornton and his team have designed a series of experiments to study blood, sweat, the skin, body hair on the mosquito bites. Advantage [6] Thornton experiment is to eliminate the influence subjects exhaled carbon dioxide generated in a separate study when certain factors may influence the maximum exclusion of other variables. Experiment concluded that no blood was found the presence of mosquito bites and the inevitable contact, skin and body hair also not affected, and the impact of sweating is very significant. Secreting and non-secreting comparative experiments, Thornton found no significant difference between them.

For this and Wood totally different conclusions, Thornton gives his own interpretation, he believes Wood obtained results are likely to be volunteers exhaled carbon dioxide - an important factor in attracting mosquitoes - the impact caused the error, and pointed out that Wood's article the presence of two statistical errors.

In this topic after twenty years of silence, Shirai 2004 Japanese scientists began to study the issue again. [7] The comparative experiments on human volunteers, are to be used for mosquito saw the mouth (not too humane for mosquitoes), but this will confuse the situation of landing and vampire. Highlights for the blood group antigens hypothesis is conducted experimental arm smear blood group antigens. The results showed that, O blood type addition to the more attractive to mosquitoes in terms of blood type A has obvious advantages over the B and AB are not obvious, and the results of Wood (O blood type A and B compared to have a significant advantage ) are not identical; but it does not have a statistically significant difference in the secretion of the same blood type and non-secreted between. Experimental arm smear blood group antigens displayed, O blood type than the H antigen blood type A antigen A more attract mosquitoes, A blood type B antigen than the B antigen is more loved by mosquitoes, is quite similar to Wood's conclusions.

But for such a result, Shirai himself that even blood group antigen test can not be used as a mosquito presence of blood empirical preference, because the actual situation in the concentration of antigen in the distribution of body surface low to undetectable level of mosquitoes. On the whole, Shirai that their study does not prove that blood type and extent of attracting mosquitoes about. Differences in the experimental results with the experimental results Wood own, Shirai speculated that a possible explanation is that different mosquito species.

In fact, the main blood attract mosquitoes theoretical hypotheses - distributed in sweat and skin different blood group antigens attracts mosquitoes - itself, the distribution of this antigen concentration is so low, as Shirai study said, mosquitoes may detect less. According to the feeding habits of mosquitoes to detect and locate distant goal for them is very important. The relatively clear understanding that mosquitoes in finding the target, mainly relies on carbon dioxide, heat and some volatile chemicals, the characteristics of these clues is easy to spread in the air greatly improves their foraging efficiency and success rate is better choice. In contrast, as the glycolipid antigens do not have this advantage, is also really did not find any blood group antigens on the exact role of mosquitoes.

Overall, these studies on blood and mosquito bites are still stuck in the more superficial extent, and have a large enough sample size, such as, a huge difference between the number of each blood type (it may be difficult to find volunteers), on a variety of variables and comparing the presence of inadequate control such problems. Despite the scientists on this issue showed interest, but research on blood still much to attract mosquitoes, and there are also many differences between these studies, making the current does not come to different blood types attractive to mosquitoes to different conclusions .

Conclusion: Mosquitoes detect and locate targets mainly by carbon dioxide, heat, volatile chemicals and other factors, there is no reliable evidence that there are differences in the attractiveness of the different blood types mosquitoes.

So stop complaining about inability to change the blood type, and pay attention to personal hygiene, proper selection of the role of mosquito repellent products more practical way.