Malaria impact and natural mosquito repellents

By several measures, mosquitoes are the most dangerous insects in the world. Conservative estimates hold mosquitoes responsible for hundreds of millions of malaria cases each year and resultant deaths.

The costs of malaria are also enormous when measured in economic terms. Highly malarious countries are among the very poorest in the world and typically have very low rates of economic growth; many have experienced outright declines in living standards in the past 30 years. Malaria has played a significant role in the poor economic performance of these countries.

The evidence strongly suggests that malaria obstructs overall economic development. Between 1965-1990, highly malarious countries suffered a growth penalty of more than one percentage point per year (compared with countries without malaria); even after taking into account the effects of economic policy and other factors that also influence economic growth. The annual loss of growth from malaria is estimated to range as high as 1.3 percentage points a year. If this loss is compounded for 15 years, the GNP level in the 15th year is reduced by nearly a fifth and the toll continues to mount with time.

However, mosquitoes also transmit a host of other diseases, including West Nile virus, yellow fever and dengue fever. There’s ample reason to take every possible measure to avoid mosquito bites even without taking into account their terrible, stinging itchiness. For the best chance at thwarting these tiny killers, know where mosquitoes live, how to repel them and how to kill them.

Those pesky mosquitoes! You’ve been bitten and have tried everything to get those annoying bites to stop itching, but it has set in and is driving you crazy! Rest assured that there are numerous ways to treat the mosquito bite to cure the itch.

Up to 20 per cent of us are highly attractive to mosquitoes and consistently get bitten more often than the other lucky 80 per cent. While genetics are thought to count for up to 85 per cent of our susceptibility, scientists have a number of ideas as to why some of us are more prone to being ravaged by mosquitoes.

So what can you do?

Insect repellent! This is probably the most effective way of reducing the risk of mosquito bites or insect bites in general.

Chemical based Diethyltouamide (DEET) is arguably the most effective chemical repellent available and has a good safety record. Research has shown that a repellent containing approximately 20 per cent will protect the wearer for about five hours. It has a good safety record and weaker formulations of 10 per cent or less are safe to use on infants from the age of two months. Other chemical agents available include icaridin and IR3535. They differ slightly in their effectiveness and characteristics but all work in the same way, producing an odour that is unpleasant to mosquitoes.

Plant based

There are a number of plant based chemicals that can offer some protection against mosquito bites. They are not as effective as DEET and are not recommended as the only protection in areas that are endemic to malaria.  These include citronella, lemon eucalyptus, and neem to name a few.

Minimising discomfort from insect bites

Insect bites can commonly cause lumps (papules), itching (pruritus), and whealing (urticarial) of the skin. Occasionally, small blisters (bullae) may develop.  However there are a number of things that can be done to minimise discomfort.

Antihistamines – taking oral antihistamines will relieve the itch and swellin, for instance, cetirizine 10mg once or twice a day.

Mild steroid cream – hydrocortisone 0.5-2.5 per cent applied twice daily for a few days can reduce inflammation and itching

Calamine lotion to affected areas

Cooling the skin e.g. with a cold compress

The bites should usually settle within a few hours to a few days.  It is important to avoid scratching the skin as this increases vulnerability to developing infection at the site of the bite. One of the many functions of skin is to act as a barrier to the outside world. If the skin becomes broken e.g. as a result of scratching, infection is much more likely to develop.

If you notice pus or discharge in or around the bite, increased pain, redness or swelling, or swollen glands, then suspect infection. This may require treatment with oral antibiotics.

What attracts mosquitoes?

Mosquitoes are attracted to dark colours such as black and navy blue, as they use vision along with scent to locate their targets.

Clothing colour

It is best to dress in light colours such as white or pastels to reduce the risk of this.

Blood type

Research suggests that certain blood types are more attractive to mosquitoes than others. A large number of the population, depending on their blood type, secretes saccharides or sugars through the skin that mosquitoes are able to sense. Studies suggest that mosquitoes seem to prefer those with Type O blood.  Indeed, mosquitoes land on skin with Type O blood nearly twice as often as those with Type A.  People with Type B blood fall somewhere in between this range.

Carbon dioxide

Mosquitoes are attracted to exhaled carbon dioxide via receptors in an organ known as the maxillary pulp and can detect their prey from up to 50 metres away. Consequently, those that exhale more gas, that is, often larger people with increased body habitus, are more likely to get bitten.

Metabolism

Studies have revealed mosquitoes seem to prefer those of us with Type O blood – and Type A the least. Aside from carbon dioxide, mosquitoes also rely on other substances, often at close range, to hone in on their targets. These include chemical and compounds secreted in skin and sweat, including lactic acid, uric acid, ammonia, steroids and cholesterol to name a few. 

Strenuous exercise can result in a build-up of lactic acid which may make individuals more susceptible. Genetic factors are likely to be involved in the composition of these substances that are naturally secreted by our bodies.

Bacteria

Large numbers of bacterial species naturally inhabit human skin.  Researchers have shown that certain bacterial subtypes present in large numbers, for example, Staphylococcus epidermidis make individuals more attractive to mosquitoes. Meanwhile other, for instance, Pseudomonas aeruginosa, appears to have the opposite effect. It also seems that having a wide diversity of bacterial types living on the skin make it less attractive.

Pregnancy

Expectant mothers are more susceptible to bites than their non-expectant counterparts. This is, however, likely to be due to the fact that they exhale relatively more carbon dioxide and have a higher resting body temperature.
Consider an all-natural solution. Experiment with non chemical solutions such as Citronella (natural plant oil). Tea tree oil and Vitamin B have reportedly helped some people repel mosquitoes.

As with any product, their effectiveness depends on the situation, your own skin chemistry, and the exact type of mosquito you are dealing with. Note, however, that so-called “alternative” solutions sometimes aren’t held to the testing standards that mainstream commercial repellents are – research alternative solutions and read testimonials before spending any money.

Natural mosquito reppellents

Learn how to keep mosquitoes away with these handy suggestions to repel mosquitoes before they attack.
Humans have been taking aim at mosquitoes since 1897, when Sir. Ronald Ross identified a tropical species as the vector for deadly malaria. It’s time to get to know your local mosquitoes and lay some defensive plans about how to keep mosquitoes away. An explosion of new mosquito-control devices and plant-based mosquito repellents has been underway. It’s also quite possible that you can outsmart mosquitoes on your own with some of the homemade, earth-friendly solutions outlined here.
 
Catnip—you can drive cats wild and make mosquitoes run in terror, according to research at Iowa State University which found that the essential oil found in the herb catnip is about 10 times more effective than DEET in repelling mosquitoes. Citronella—the old standby. Use only pure essential oil of citronella—not fragrance oil.  Oils purchased in bulk for burning are not adequate for applying topically to your skin.  For your skin it is best to get a high quality citronella essential oil from a natural food store. 

While it’s not as effective as catnip, it’s still a good option.

Garlic—eat lots of fresh garlic—mosquitoes can’t stand the stuff.

Lavender essential oil smells great and is a commonly used and effective mosquito repellent.  It’s best diluted in a carrier oil like apricot kernel, sweet almond, or coconut oil.  If you can find organic soy oil, it is also a good option since it also keeps mosquitoes at bay.

Neem oil or neem seed oil (Dogoyaro derivative):  According to a study by the U.S. National Research Council, neem oil is more effective than DEET.  The results were confirmed by scientists at the Malaria Institute in India and in research cited in the Journal of the American Mosquito Control Association. Neem is a plant that grows well in Nigeria.

Organic soy oil—Research cited in The New England Journal of Medicine found that repellents made of soybean oil are just as effective as DEET-containing repellents. Soy oil is inexpensive and easy to find, making it an excellent choice. Plus, it is an excellent body moisturizer. As an aside, research shows that an ingredient in soy can slow the growth of body hair when applied topically.  Choose organic soy oil if possible since many soy crops are now genetically-modified.

Lotus (Nelumbo nucifera)—New research published in the Asian Pacific Journal of Tropical Medicine shows that lotus is an effective mosquito repellent and also helps kill mosquito larvae.  Since lotus grows in water it is a good option as a natural repellent in backyard ponds and water features rather than something that is applied topically.
Black pepper (Piper nigrum)—New research from the same study shows that an extract (the study used an alcohol extract but black pepper essential oil would probably work, too) of black pepper is effective in repelling mosquitoes.

Lemon Eucalyptus Oil

Used since the 1940s, lemon eucalyptus oil is one of the more well-known natural repellents. The Centers for Disease Control and Prevention (CDC) has approved eucalyptus oil as an effective mosquito repellent. A recent study showed that a mixture of 32 per cent lemon eucalyptus oil gave more than 95 per cent protection against mosquitoes for three hours.

You can create your own mixture with one part lemon eucalyptus oil to 10 parts sunflower oil or witch hazel. Note: University of Florida researchers caution against using the mixture on children under three years old.
Lavender

Crushed lavender flowers produce a fragrance and oil that can repel mosquitoes.
You can grow lavender in your outside garden or in indoor planters. Crush the flowers and apply the oil to bite-sensitive areas of the body, such as your ankles and arms. Alternatively, drop some lavender oil on a clean cloth and rub it onto the skin.

Lavender has analgesic and antiseptic qualities. This means that in addition to preventing mosquito bites, it calms and soothes the skin.

Cinnamon Oil

Cinnamon is more than just a great topper to applesauce or oatmeal. According to a study conducted in Taiwan, Cinnamon oil can kill off mosquito eggs. It can also act as a repellent against adult mosquitoes, most notably the Asian tiger mosquito.

A concentrated dose of cinnamon oil on your skin can be irritating, so be careful.

To make a diluted one per cent solution, mix ¼ teaspoon (or 24 drops) of oil for every four ounces of water. You can spray the fluid onto your skin or clothing, around your home, and onto upholstery or plants.

Thyme Oil

When it comes to repelling malarial mosquitoes, thyme oil is one of the best at providing protection. In one study, hairless mice had five per cent thyme oil applied to the skin, with a 91 per cent protection rate.
For a homemade brew, combine four drops of thyme oil to every teaspoon of base oil, such as olive or jojoba oil. For a spray, mix five drops of thyme oil with two ounces of water.