Medical services are widely available. For emergencies, the best bet is to find the nearest hospital and go to its emergency room. If the problem isn't urgent, call a nearby hospital and ask for a referral to a local physician, which is usually cheaper than a trip to the emergency room (where costs can be $500 or so before any treatment).
Pharmacies are abundant, but prescriptions can be expensive without insurance. However, Americans may find Canadian prescription drugs to be cheaper than drugs at home. You're allowed to take out a 90-day supply for personal use (it's technically illegal to bring them into the USA, but overlooked for individuals).
Most are acquired by mosquito or tick bites, or environmental exposure. The Public Health Agency of Canada (www.phac-aspc.gc.ca) has details on all listed below.
Giardiasis Intestinal infection. Avoid drinking directly from lakes, ponds, streams and rivers.
Lyme Disease Occurs mostly in southern Canada. Transmitted by deer ticks in late spring and summer. Perform a tick check after you've been outdoors.
Severe Acute Respiratory Syndrome (SARS) At the time of writing, SARS had been brought under control in Canada.
West Nile Virus Mosquito-transmitted in late summer and early fall. Prevent by keeping covered (wear long sleeves, long pants, hats, and shoes rather than sandals) and apply a good insect repellent, preferably one containing DEET, to exposed skin and clothing.
Cold exposure This can be a significant problem, especially in the northern regions. Keep all body surfaces covered, including the head and neck. Watch out for the 'Umbles' – stumbles, mumbles, fumbles and grumbles – which are signs of impending hypothermia.
Heat exhaustion Dehydration is the main contributor. Symptoms include feeling weak, headache, nausea and sweaty skin. Lay the victim flat with their legs raised; apply cool, wet cloths to the skin; and rehydrate.
No special vaccines are required or recommended for travel to Canada. All travelers should be up to date on routine immunizations.
Canada offers some of the finest health care in the world. However, unless you are a Canadian citizen, it can be prohibitively expensive. It's essential to purchase travel health insurance if your regular policy doesn't cover you when you're abroad. Check www.lonelyplanet.com/travel-insurance for supplemental insurance information.
Bring medications you may need clearly labeled in their original containers. A signed, dated letter from your physician that describes your medical conditions and medications, including generic names, is also a good idea.
MD Travel Health (www.mdtravelhealth.com) General health resources.
Public Health Agency of Canada (www.phac-aspc.gc.ca) Canadian health resources.
World Health Organization (www.who.int) General health resources.