The American nightmare: diseases and health dangers in the USA

Don't be lulled by the American dream – the USA actually has some rather nasty beasties lurking in its wild places...

Most travellers might imagine that the USA is a supremely safe destination. But heading into the wild comes with some warnings, even there. The US boasts a varied array of national parks in which there is more than enough scope for falling off mountains, getting frostbitten or hypothermic, succumbing to heatstroke or being boiled alive in hotsprings. Make sure you know the terrain you’re heading into and prepare accordingly. There are also wildlife threats that can cause problems. Here’s a few to know before you go...

1. Mosquitoes & midges

Where? Countrywide.
Why? Midges are particularly infuriating along the Atlantic Coast, Gulf Coast, San Francisco Bay region and south-western deserts. Fortunately they’re only irritating and spread no disease. Mosquitoes are worse in the south (especially Florida), where huge amounts are spent on killing the insects that spread incurable diseases such as West Nile fever, dengue and the newly recognised Heartland virus.
Top tip: Bite prevention is essential – repellents will also keep off chiggers and maybe horseflies.

2. Ticks

Where? Commonest in hardwood forests.
Why? Ticks in the Americas offer a selection of infections – nine in all. If you’re out in the wilds, particularly if brushing through vegetation where animals roam, do a tick check each evening and know how to remove ticks intact if you find one.
Top tip: Although ticks are not insects, insect repellents do work.

3. Bears

Where? Alaska, the Rockies.
Why? There are about eight attacks a year, of which two or three are fatal. Campers are often targeted – especially messy campers who leave food rubbish lying about. Be tidy, and hang food and toothpaste up a tree away from your tent.
Top tip: If faced with a bear, raise your arms over your head (to appear taller), speak calmly and walk – don’t run – away.

4. Moose

Where? Alaska and the Upper Great Lakes.
Why? The moose is considered Canada’s most dangerous animal – there are about four fatalities annually; they’re especially dangerous if defending their young. That said, many more people (300 or so a year) are hurt when their cars hit one of these substantial animals.
Top tip: Drive cautiously in moose country, especially in winter when collisions are most likely.

5. Mountain lion

Where? The Rockies.
Why? Mountain lions tend to avoid humans. They attack one or two people a year on average and there are occasional deaths – around one every six years.
Top tip: If you encounter a lion, walk calmly away; don’t run.

6. Snakes

Where? Countrywide.
Why? Snake-bite estimates range from 7,000 to 45,000 a year, of whom nine to 14 die. Of the 19 venomous species here only four are considered dangerous: the cottonmouth; the copperhead; rattlesnakes; and the little stripy coral. All sea snakes are venomous but rarely aggressive.

Top tip: When building a campfire, lift logs away from you to give any snakes an escape route.

7. Alligators

Where? Florida.
Why? Alligators take a few lives each year, mostly in Florida. If there are signs warning against swimming, take heed and be very cautious at the water’s edge. Never approach an alligator.
Top tip: Be extra vigilant in summer: 75% of attacks occur from May to September, when males become more aggressive.

8. Skunks

Where? Forested areas.
Why? A skunk spray can cause temporary blindness, vomiting and has even been blamed for a heart attack. But the biggest issue is the lingering stench, best treated by rubbing the skin with a mix of a litre of 3% hydrogen peroxide, a quarter cup of baking soda and a teaspoon of liquid detergent.
Top tip: Locals swear by bathing in tomato juice but this is unlikely to reduce the odour much.

9. Scorpions

Where? Mainly southern desert regions.
Why? Bark scorpions are dangerous but an antivenom means fatalities are rare. Stings hurt a lot though. In Mexico, where medical facilities aren’t so good, scorpions kill over 1,000 children a year.
Top tip: Shake out shoes and clothes before putting them on.

10. Spiders

Where? Countrywide.
Why? Spiders should be treated with respect – the US has widows, browns and sac spiders, which can all be remarkably unpleasant if provoked. They are seldom life-threatening but some bites lead to local tissue death.
Top tip: If using an outside toilet, rattle the seat before sitting to scare off any spiders.

11. Poison ivy

Where? Forested areas.
Why? Poison ivy and oak secrete oil, which causes a delayed hypersensitivity reaction and rash. The oil is best removed with rubbing alcohol. The toxic oil can be spread from person to person, including on towels.
Top tip: A wet compress, calamine lotion or hydrocortisone cream can be applied to reduce itching and blistering.

12 Giardia

Where? Countrywide.
Why? Giardia is relatively common, people catch it from swallowing water when lake swimming and, sometimes, in contaminated pools. It can get into seafood too, so if you develop something like irritable bowel symptoms after a US trip get checked.
Top tip: Report abdominal bloating to your GP – there are good treatments.

13 Ciguatera

Where? Most common on Hawaii, the US Virgin Islands, Puerto Rico and Florida.
Why? The strange condition of ciguatera seafood poisoning is responsible for an eighth of all reported food poisoning cases in the US. Symptoms usually begin (within six hours) with gastrointestinal upset (vomiting, watery diarrhoea, cramps), which settle in 24-48 hours. There is often lip tingling and later a reversal of the hot-cold sensation: cold things are burning to touch. These symptoms can take many weeks to settle.
Top tip: Shun large carnivorous reef fish (such as barracuda and grouper) – fish further up the food chain are most suspect.

14. Bats

Where? Countrywide.
Why? The US boasts arguably the world’s nastiest cave – Frio in New Mexico. The atmosphere in Frio is so thick with bat urine that, when inside, it is possible to catch rabies simply by breathing. Any cave with big bat populations also comes with a risk of the pneumonia-causing histoplasmosis fungus. Potential cave-explorers should ensure they are immunised against rabies, and masked against histo.
Top tip: Never handle a bat.


Dr Jane Wilson-Howarth’s updated e-book Your Child Abroad is available only from Bradt Travel Guides