1.Head Lice spread over caps

Head lice are wingless insects spending their entire lives on the human scalp and feeding exclusively on human blood. Humans are the only known hosts of this specific parasite, while chimpanzees host a closely related species, Pediculus schaeffi. Other species of lice infest most orders of mammals and all orders of birds, as well as other parts of the human body (Buxton, 1947).

In many cases when its known that lice are present, lice comb and special shampoos are purchased, cuddly toys, duvet covers and clothes are chemically treated in order to remove head lice and prevent them from spreading from one person to another. While it is a good practice, it is not necessary for the case of head lice as contrary to a popular assumption, head lice do not spread over objects, but almost exclusively via direct head contact. This is proven by several studies, among others from Poland and Australia, in which the researchers collected thousands of lice from children's heads during various louse plagues, but none in caps, on stuffed animals or even chairs and tables. (Feldmeier, 2012)

2.Rats directly transmitted the plague

Plague is an infectious disease caused by the bacteria Yersinia pests, a zoonotic bacterium, usually found in small mammals and their fleas. It is transmitted between animals from their fleas. (WHO, 2017).

However, the rats themselves are victims of the Black Death. The natural reservoir of the plague bacteria are prairie dogs, ground squirrels and marmots, from which the pathogen then jumps over plague fleas

3.Fleas don’t last long without blood

Fleas are small flightless insects that form the order Siphonaptera. As external parasites of mammals and birds, they live by consuming the blood of their hosts. Adult fleas are up to about 3 mm (0.12 in) long and usually brown. Their bodies are flattened sideways which enables them to move through their host's fur or feathers (Gullan et al. 2016).

These insects are actually quite tough. After a blood meal, the animals can survive for several months without further food until a new victim appears. Probably the myth meant that fleas need a permanent blood supply.

4.Ticks can jump from trees on their host

Anyone who now roams through forests and fields should always check his body for ticks. Even though the bloodsuckers are not harmless, they can transmit dangerous diseases such as TBE or Lyme disease. Ticks are small arachnids, part of the order Parasitiformes. Along with mites, they constitute the subclass Acari. Ticks are ectoparasites (external parasites), which survive by feeding on the blood of mammals, birds, and sometimes reptiles and amphibians (Barker, 2004).

There is a big misunderstanding on how a tick can attach on our body. Many people think that ticks jump onto our body from trees or other high plants. That is not true! Ticks are mostly attached on our skin from the ground. They don’t have the ability or biomechanics to jump. If you are surprised to find them in upper areas of your body, that is not because they jump from trees onto you, but because they crawl from your leg to anywhere on your body.

5.Bedbugs are caused by lack of hygiene

Bedbugs’ primary hosts are humans, and are one of the world's major "nuisance pests". Although bedbugs can be infected with at least 28 human pathogens, no studies have found that they are capable of transmitting any of these insects to humans (Kolb et al. 2009).  Bedbug bites or cimicosis may lead to a range of skin symptoms from no visible effects to prominent blisters, skin rashes, psychological effects, and allergic symptoms (Doggett & Russell, 2009).

We usually associate bedbugs with poor hygiene but in reality bedbugs don’t discriminate between clean or dirty places. They are simply looking for humans to feed on. They are common in places that have high occupancy such as rental apartments, hotels, public transportation, and even hospitals. Crowded places make it easier for bedbugs to hitch on people or personal belongings and this way end up in your house or apartment where they start the process of infestation (the state of being invaded or overrun by pests or parasites).  

6.All parasitic worms are harmful

Our gut houses hundreds of worms and this exaggerated myth can scare many of us. Roundworms and flatworms often live peacefully in our digestive tract. There is increasing evidence that these invertebrates may even benefit our health. For example, studies showed that helminths prevent or improve colitis by the induction of regulatory T cells and modulatory cytokines. Biomedicists believe that lack of worm infestation is a reason for the rapid increase in autoimmune diseases such as irritable bowel and allergies in industrialized countries. Physicians now use parasitic worms to induce the immune system to prevent autoimmune diseases (Summers et al. 2005). It’s true that there are parasitic worms which we don’t want in our body, however there are many of them which bust our health and benefit us. Thus, not all parasitic worms are harmful.

7.Darkness prevents mosquito attacks

Some types of moths are known to navigate around using light clues or a constant angle relative to a light source. Mosquitos are also thought to move in a similar manner however, if the blood-sucking insects decide to bite us or not doesn’t depend on light.  They use characteristic scents of their victims to find them and inject proboscis to suck up blood. Various studies have already shown that, for example, sweat odor has a particularly attractive effect on hymenoptera species: they specifically follow this scent trail down to the skin, where they then stab (Logan et al., 2008) no matter if it’s daytime or nighttime. Additionally, people who are densely populated with Staphylococcus bacteria, attract the insects more than flesh blood. Skin bacteria play an important role in the production of human body odors. When cultured in vitro, skin bacteria produce volatiles that attract A. gambiae. These volatiles could be used as mosquito attractants or repellents (Verhulst et al., 2010)

8.Mice like to eat cheese

In classic comics, mouse traps are preferably stocked with cheese reflecting the myth that mice love cheese. Scientists of the Manchester Metropolitan University have found that cheese is not their preferred food. In facts, they don’t like cheese at all and in many cases they shy away from some types of odorous cheeses.  Although, they often stretch their nose in the direction of cheese, that is only because of its strong smell. If given the choice, they would much rather eat foods containing high level of sugars such as fruits or grains, as they occur in nature. Modern traps contain different attractants that release a chocolate scent – and which the mice also find appealing (BBC, 2015). Nobody knows how the myth that mice prefer cheese started but now we know that they actually don’t like cheese, however if hungry they will pretty much eat anything.

9.Tapeworms can help us lose weight

There are just a few countries which allow this diet to be promoted and unsafely used by people in order to lose weight. It is usually done in a procedure of 5 steps and the idea behind the tapeworm diet is that once the tapeworms are ingested and settle in your intestine, they will consume a portion of your food along with all the nutrients provided by that food and this way you will lose weight. This diet is as gross as it sounds. The fact that this diet helps remove unwanted weight is questionable and not proven. In addition, tapeworms take important nutrients and minerals that we need for our health and they can become the source of disease and infection. The most common side effects are headaches, diarrhea, constipation, bloating, abdominal pain. Death caused by tapeworms is also a possibility. In conclusion, this diet is definitely not safe and its effectiveness is questionable.



COPYRIGHT: This article is property of We Speak Science, a nonprofit institution co-founded by Dr. Detina Zalli (Harvard University) and Dr. Argita Zalli (Imperial College London). The article is written by Dardan Beqaj, M.Sc. Microbiology, Eberhard-Karls University of Tübingen).



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