By and large, Puerto Rico is a safe destination. Millions of tourists visit its shores each year without incident. Of course, San Juan carries the inherent risks of most large urban sprawls in the Caribbean (and pretty much everywhere else), and there are basic safety tips that every traveler should consider when traveling.
Still, many tourists want to be fully informed about the risks of traveling to an exotic destination. Certain risks—like dengue fever and hurricanes—are infrequent and seasonal, and affect not just Puerto Rico but the entire region.
The best advice that can be given to the weary traveler is to check the Center for Disease Control and Prevention on health information for travelers to the island. Having said that, here's a rundown on the basic health and safety risks that can affect Puerto Rico.
The most well-known safety risk of traveling to Puerto Rico is probably its proximity to hurricanes. The truth is, it's been decades since a storm or hurricane caused the kind of damage that gives hurricane season such a bad reputation. And it's also true that some islands have it worse than others. A combination of good luck and the geographic position has kept Puerto Rico relatively safe from the destructive paths of hurricanes.
If hurricane season is a deal-breaker for your travel plans, understand that it's a long season: we're talking June to November, prime summer months. It's a time when scores of visitors descend on the island without incident. Of course, it's impossible to predict when a severe storm can come along to dampen your holiday spirit, especially when you're booking months in advance. If a storm does hit, the best protection you've got is to stay indoors and ride it out.
Mosquitos are a nuisance all over the tropics. And dengue fever, which is transmitted by mosquitos, has been reported by the CDC as a leading cause of death in the islands. Puerto Rico has had its share of cases and has even declared dengue epidemics in the past. Your best protection against this fever is to wear sunscreen, mosquito repellent and long-sleeve shirts and pants. Dengue is a credible threat, and while it can be managed, the best advice is to keep to indoor air-conditioned areas if it rises to epidemic levels in the city or island you're in.
Food and Water
According to the CDC, Puerto Rico has the same standards for drinking water and food safety as the rest of the United States, so you generally don't need to worry about drinking tap water. However, if you're visiting remote parts of the island, bottled water may be advised.
The one thing I would mention is that there have been cases of ciguatera, a type of fish poisoning that comes from certain reef fish, like barracuda, grouper, and snapper. Symptoms include nausea, vomiting, cramps, headaches, and muscles aches or weakness. Again, this is certainly not restricted to Puerto Rico but can be found throughout the Caribbean. When in doubt, check travel warnings or, if you're already on the island, ask about the fish before ordering (or avoid fish entirely).
Flora and Fauna
Puerto Rico has no large predators, so thoughts of Chupacabras (one of the more entertaining myths to come out of the island) attacking you should be put to rest. But there are some animals to be wary of. If you go snorkeling or diving in the waters here, you might see jellyfish, barracuda, sharks, and other marine species that know how to bite or sting.
On land, your biggest nemesis when you get out of urban areas might be wild dogs and mongooses. One of the weirder historical anomalies of Puerto Rico was the decision to import mongooses to take care of the local snake population. Well, the U.S. Forest Service reports that mongooses are now the principal carrier of rabies on the island. So if you get bitten by a mongoose while you're visiting El Yunque, you should wash your wound and seek medical help immediately.
Similarly, there are numerous poisonous plants and flowers growing in Puerto Rico, but the Forest Service reports that El Yunque's most visited areas are pretty safe from these dangers.