Reading through this list might just make you want to cancel your upcoming vacation plans. You’ll find out about some truly horrifying parasites that have the ability to invade the human body. If you choose to continue reading, expect nightmares tonight. But don’t change your vacation plans straight away. You should know that although some of these parasites are endemic to far away places, there’s a chance you can come in contact with more than a few in your own hometown. It’s also important to note that while some of these parasites seem unfathomable to you, there are people who have to deal with them on a regular basis. In places where these parasites are common, they’re not just a scary thought, they’re real and often life threatening in places where good medical care is hard to find.

15. Giardia Lamblia

Giardia Lamblia is a parasite that can cause gastrointestinal problems including very bad diarrhea. The parasite can be contracted from drinking contaminated water or food. It can also be found in the soil and on surfaces. It’s most commonly transmitted via water, though. Symptoms of this parasite can show up up to three weeks after contracting it and the symptoms can last up to six weeks. Giardia is actually pretty common. So you might not even have to travel far to contract it. In the United States, it’s the most commonly acquired parasite. You can also swallow Giardia cysts if you drink from bodies of water while you’re out on a hike and don’t take the time to treat it.

14. Cyclosporiasis

Cyclosporiasis is another parasite that affects the digestive system. Symptoms include diarrhea, weight loss, painful cramping, nausea, and a possible low-grade fever. Like giardia, it’s transmitted via contaminated food or water. You might contract the parasite if you’re heading to a tropical or sub-tropical country for vacation, but there have also been cases of outbreaks in North America that have been linked to food contamination. If you think you may have cyclosporiasis, you’ll need to make sure you stay hydrated. You also don’t want to forget to see a doctor so you can get the appropriate treatment which is usually a course of antibiotics.

13. Trichinosis

Trichonosis (also known as Trichinellosis) is a parasite that can be contracted if you eat meat that’s undercooked or raw from an infected animal. Symptoms show up rather quickly and are mild at first. Usually a bout of diarrhea and vomiting. A few weeks later, persons infected may experience fever, fatigue, itchiness, diarrhea, and more uncomfortable symptoms. The severity of the infection depends on how many worms were ingested. If you’re eating out on vacation, make sure the meat is well cooked. If you’re heading off on a hunting expedition for a weekend, make sure you’re not eating any of that game raw, especially if it’s bear meat.

12. Fascioliasis

You’ll notice as we creep down this list that the parasites get increasingly scary. Fascioliasis is a parasite that is also called ‘the common live fluke.’ That name alone makes us cringe. You might come into contact with this parasite if you’re hanging around sheep and other livestock. Visiting a farm on your holiday? Careful now, make sure if you’re eating produce from a farm that everything has been well washed. If you’re lucky, fascioliasis won’t produce any symptoms. Otherwise, when the adult flukes make their way into the ducts of your liver you’ll likely experience a fever, discomfort, and pain in the abdomen. Thankfully, the parasitic infection is treatable.

11. Malaria

You’ll probably be familiar with this disease more than any other on the list. It causes many deaths worldwide when left untreated. Malaria is a transmitted by mosquito. It’s endemic to sub-Saharan Africa and South Asia. The disease causes flu-like symptoms in its most mild form. In more severe cases, organ failure can occur. Eradication of malaria in the United States was achieved in the 1950s but since then there have been a few outbreaks. Most cases are related to persons traveling back to the US from Africa or South Asia. If you’ll be traveling to those areas, you can take an anti-malarial drug to help prevent infection.

10. Leishmaniasis

This nasty parasite is found in several places around the world including the tropics, subtropics, and some parts of southern Europe. You can contract this disease by getting bitten by phlebotomine sand flies. Leishmaniasis can either affect the skin or internal organs, depending on the form of the parasite that you contract. When affecting the skin, sores will be present (as pictured above). People with sores will often notice their glands swell. It’s likely that you won’t even notice you’re being infected because the sand flies that transmit the disease are barely noticeable. If left untreated, the form of leishmaniasis that affects internal organs is usually fatal.

9. Lyme Disease

Are you thinking about booking a vacation to a national park so you can enjoy the great outdoors and hike to your heart’s content? You’d better be aware of Lyme Disease. The disease is actually transmitted by bacteria (via ticks) and not parasites, but ticks creep us out and we thought this definitely belonged on the list. After being bitten by an infected tick you might experience fever and a very unique bullseye-looking rash. If left untreated, Lyme Disease can cause even more problems down the line including, but not restricted to, severe headaches, joint pain, heart issues, and short-term memory problems. If you realize you’ve been bitten by a tick, the earlier you get treatment, the better.

8. Guinea Worm

Anything with worms really grosses us out. The Guinea worm parasite is common in poor parts of Africa. The most recent reported cases occurred in Chad, Ethiopia, Mali, and South Sudan. The parasite is transmitted via infected drinking water. When Guinea worm larvae are ingested they move through the body and continue to grow. Some adult worms can grow as big as 3 feet long. It’s the stuff of nightmares. But does the adult worm stay in the body forever? Nope. At one point, it will have the desire to exit. To leave the human body, the worm causes blistering, usually in the lower half of the body, and exits up to 72 hours later. There is unfortunately no cure for this disease and there is no way to prevent it.

7. Loa Loa

Here’s another parasitic worm that’s the stuff of nightmares. Loiasis (also called the African eye worm) is transmitted via the bites of deer flies. The deerfly passes on the worm, called Loa loa, to humans. You’ll find these annoying flies in certain rainforest areas of Africa. The parasite can cause itchiness and swelling but most horrifyingly of all, it can cause a worm to appear in your eye. Those infected with the Loa loa worm can have it surgically removed but that doesn’t cure the disease. Medications can be administered but they have some serious side effects. If you’ll be traveling to areas where you can contract the parasite, it’s possible to take preventative meds as well.

6. Chagas Disease

Chagas Disease is a parasitic infection that can last for life if you don’t bother to get it treated. When you are first infected with the parasite symptoms are mild. Complications can arise during the chronic stage of the disease. Most of these complications are heart-related and very serious. The insects that transmit the parasite are called triatomine bugs. They’re also known as ‘kissing’ bugs. The little blood suckers are found in the south of the US and basically everywhere south of the US border. If you’re in the United States, the only source of medication to treat Chagas Disease is via the CDC.

5. Lymphatic Filariasis

Lymphatic Filariasis is a parasite that originates from the tropics. It causes teeny-tiny thin worms to invade the human body’s lymphatic system. The disease is transmitted via mosquito bites but you’ll need to get bitten several types to get the disease. The parasitic infection causes swelling of the lymph nodes and can cause elephantiasis which can then lead to disability. Because the parasite causes damage to the body’s lymphatic system, people who have contracted this parasite are often more prone to illness and bacterial infections. The disease does have a treatment, but the medication, unfortunately, does not prevent transmission of the disease.

4. Sleeping Sickness

African Tryponosomiasis (also known as sleeping sickness) is caused by a parasite that’s transmitted via another gross fly called the tsetse fly. The fly is endemic to rural parts of Africa. It’s a very serious disease that’s fatal when untreated. Symptoms of sleeping sickness can develop up to three weeks after being bitten. The first symptoms, among others, are that of fever, fatigue, aches and pain. As the disease progresses, it invades the central nervous system and can even cause personality changes. The disease does have a cure but there is no vaccine available to prevent infection. If you contract the disease and get treatment, you’ll need to follow up for 2 years to ensure it’s gone.

3. Cutaneous Larva Migrans

So this isn’t a fatal disease, so it’s not scary in that sense, but it really grossed us out. Cutaneous Larva Migrans is a parasite that can be contracted via contaminated soil or sand. So, basically, the ground. You can get this parasite if you’re traveling to the Caribbean to enjoy the sunshine and it’s also found in Africa, Asia, and South America. If you contract CLM you might notice snake-like tracks popping up on the surface of your skin. You’ll want to scratch yourself raw. You can get treatment for this parasite but the larvae should only live up to six weeks. Thank goodness. We’ll be wearing full body scuba suits to the beach from now on.

2. Onchocerciasis

Onchocerciasis is also known as River Blindness. The parasite is transmitted via black flies. Yeah, we really hate flies, too. The black flies that transmit the disease tend to live near rivers. Most of the cases of River Blindness occur in Africa but there have been cases in the Middle East as well. You’re more likely to contract the disease if you’re a long-term visitor. The disease can blind and disfigure those who are infected. The parasite can also cause the skin to itch and cause nodules to form under the skin. There are treatments for the disease but prevention is an important part of keeping this disease at bay.

1. Naegleria Fowleri

Naegleria fowleri is not technically a parasite, it’s actually an ameba. But it’s super terrifying so we thought it deserved a special place on this list. It’s usually found in fresh water. If you’ll be enjoying freshwater swims on your next vacation, you might want to block your nose! The ameba gets into the human body via the nasal cavity and then heads straight to the brain where it essentially eats away at the tissue. Most cases of Naegleria fowleri have been fatal but a medication called miltefosine looks to be a promising treatment avenue for the ameba. If you avoid getting water up your nose during your life, you’ll be at low risk for contracting this deadly organism.

Source: cdc.gov