Insects and Bugs
Insects and Bugs
From flies, worms, mosquitos, ticks to the dreaded snail, here are some insects and bugs you’ll want to steer clear of while you’re abroad.
The Mosquito
This tiresome creature is responsible for serious diseases and countless deaths right across the world.
Chikungunya Fever is predominant in Sub Saharan Africa, South East Asia and India. It causes joint pain fever, photophobia (intolerance of light), vomiting and a rash.
The word Chikungunya comes from a local African dialect where the disease was first seen and describes the arthritic contortions seen in sufferers. Treatment is symptomatic, treating the symptoms rather than the cause, and people usually recover within a week.
Dengue Fever is an arbovirus transmitted to humans by mosquito. Dengue fever is most common in South Asia and South East Asia, India, Central America, South America and more recently the Western Hemisphere.
50-100 million people are infected each year. Symptoms include fever, headache, eye pain, and painful myalgia and arthralgia, which is why it’s also called break bone fever.
Most cases lead to recovery but some people suffer the complications associated with haemorrhagic fever. There is no vaccine, so use that DEET insect repellent!
Yellow Fever is a flavivirus transmitted by mosquito bites. The main target is monkeys but humans can be accidentally infected. This can cause large epidemics when mosquitos bite infected people then go on to bite the uninfected, passing the virus on.
Yellow fever occurs in Sub Saharan Africa and South America. Vaccination is essential and a public health certificate is required in many countries.
The disease has a quick incubation period with symptoms including chills, headache and muscle pain, all showing within 3-6 days. This explains why countries like India will only allow people coming from a yellow fever risk country to enter after 10 days, ensuring they have not been infected.
Japanese Encephalitis also comes from mosquitoes, although the original hosts are pigs and wading birds. As the name suggests, the disease causes swelling of the brain, and it’s found across most of Asia.
The vaccine dramatically reduces your chances of death, which is good news since the disease has a 30% death rate.
Last but not least is Malaria, a protozoa transmitted via the bite of the female Anopheles Mosquito. It’s the most significant parasitic disease of our time and 3 billion people live in endemic areas, 1-3 million of whom die of it annually, mostly children.
There are a number of different species of malaria-bearing mosquito in different parts of the world. P. falciparum, found predominately in Sub Saharan Africa, is the most severe form.
Acute malaria involves tiredness, aching, fever, rigor and the shakes. You might also experienc vomiting, diarrhoea and convulsions, a headache and a cough. It can also lead to cerebral involvement, ie. brain problems, which comes with a 20% death rate.
The only way to avoid malaria is to avoid being bitten, which makes a good repellent a travel essential.
Chrysops Horse Fly
The Chrysops Horse Fly lurks in the central African rain forests. The fly’s bites inject filarial larvae into the skin, resulting in itching. As the larvae mature they move into the body’s deeper muscle layers, where they create pain and temporary swelling in the limbs.
The growing worms often migrate to the eyes, where you can see them for minutes, or even hours, travelling across the conjunctiva. Freaky.
The Sand Fly
The Sand Fly is guilty of many sins and Leishmaniasis is one of them. When you’re bitten by a Phlebotomus or Lutzomyia sandfly the Leishmaniasis parasite multiplies in the skin. After several weeks or months a nodule appears and slowly grows before ulcerating.
Some infections go away on their own but others can destroy the lips and upper part of the nasal cavity.
Sand flies can also carry Visceral Leishmaniasis, also called kala-azar, black fever or Dumdum fever and the most serious form of Leishmaniasis.
The Black Fly
The Black Fly carries a parasite found in fast flowing water in the Western Africa savannah. Once the parasite enters the body via the black fly’s bite, it migrates to the bones and eyes where it can cause blindness, hence the name River Blindness.
The disease can also cause atrophy, where the skin wastes away, plus a loss of skin elasticity and excessive wrinkles around the buttocks.
The Tetse Fly
The Tetse Fly causes African Trypanosomiasis or Sleeping Sickness, where the Tsetse fly hosts Trypanosoma brucei. The disease comes in two forms, each with its own symptoms.
An infected tsetse fly bite can case skin chancre, a hideous wound full of living, growing protozoa. Rhodesian Trypanosomiasis, which often develops as a chancre, is common in the savannah and cleared bush of South East Africa.
Gambian Trypanosomiasis rarely forms a chancre. The incubation period is often much longer and leads to chronic infection. Central nervous system infection can lead to headaches, personality changes, forgetfulness, psychosis and then convulsions and death. And you get very sleepy, hence the name.
When left untreated both forms have a high death rate.
The Reduviid Bug
The Reduviid Bug is responsible for American Trypanosomiasis or Chagus Disease, and it could be hiding in the walls of your room.
The bug leaves its poo on your skin, eyes and mucous membranes. While it snacks on you, it passes on the Trypanosoma Cuzi parasite. Domestic animals and armadillo usually host the parasite, but in desperate times humans get it.
The infection causes swelling at the bite site. You may wake up with only one workable eye for instance, the other looking like you’ve been in a fight.
In the chronic phase the parasite often lives in the heart muscle, where it can cause arrhythmia – where your heart beats out of time – and even sudden death.
Canine Hookworms
Canine Hookworms are responsible for Cutaneous Larva Migrans. When filariform larvae bury themselves in the skin, they leave a visible itchy track mark. They eventually die, or are ideally killed off by a dose of the drug Albendazole.
The Guinea Worm
Don’t drink the water! If you do you might swallow a crustacean called The Guinea Worm, which releases larvae into your body cavities and causes Dracunculiasis.
Once in your body the larvae mature and mate. The females can grow to 100cm before, months later, they migrate to the upper layers of the skin where an ulcer forms. At this stage you’ll see the tip of the worm coming out. If you try to wash it out, more larvae are released from the mother worm.
Local treatment usually involves wrapping the tip of the worm around a stick and slowly, day by day, pulling it out a bit at a time. On the other hand the drug Metronidazole will do the trick, a much better and faster solution!
The Snail
Schistosomiasis or Biharzia affects around 200 million people in the world. The culprit is the blood Trematode Fluke, which gets inside snails and uses them as a host.
After some time the snails release millions of schistosome cercariae, tiny larvae which penetrate the skin of swimmers, bathers and others entering infested rivers and lakes.The larvae get into your blood vessels then migrate to the liver where they develop into worms.
Schistosomiasis is a slow disease. Migrating worms cause egg granulomas over time, places where eggs are deposited. This can affect every part of the body and causes colitis, renal failure and even bladder cancer.
The disease can be treated early with the drug Praziquantel, but it makes sense to avoid infection by steering clear of risky water: no swimming, and no standing around in the water either.
The Tick, Flea and Mite
- Tick-borne Encephalitis, spread by Ticks, is commonly found in forested areas of Eastern Europe. The virus affects the central nervous system and vaccination is essential if you’re planning a hike or trip to the countryside in an affected area
- Typhus or Rickettsiosis is transmitted by Fleas, via rats to humans, and it’s worldwide. It’s very similar to Louse Born Typhus, found in colder regions of the world, where louse bites releases poo into the skin and can cause delirium
- African Tick Typhus is transmitted from cattle and game animals to travellers camping in long grass. The disease causes a rash but not death
- And lastly we have Scrub Typhus, transmitted from a Rodent Mite and common in East Asia. The initial bite is often painless, but after an incubation period of around 6-20 days you’ll get headaches, shakes and chills, swollen lymph glands, sore eyes, fever, lost appetite and general apathy. The best cure for the disease is antibiotics but, as with all diseases carried by insects and bugs, it’s best to avoid being bitten in the first place
Contact us for help and advice
We’re always happy to help and advise you about how to stay safe from insect-borne diseases abroad, figure out the risks and protect yourself with vaccinations wherever possible.
