Sharks Kill Fewer Americans Than Dogs. Here Are America's Deadliest Animal Threats

You might fear a shark in the water, but some of America's deadliest animal encounters happen without a single bite.

In 2023, crashes involving animals killed 234 people in the United States. Unprovoked shark attacks killed just two.

So what happens when we put nine animal-related threats into a head-to-head tournament, with each matchup decided by the number of Americans who die each year?

We used U.S. mortality data from 2018 to 2023 to create our tournament. Every contestant is judged by the same measure: average deaths per year.

A shark is a formidable predator. However, if we start counting the number of Americans killed by them, they don't even come close to dogs. Between 2018 and 2023, unprovoked shark attacks killed just eight people in the United States. During those same six years, dogs killed 420 people through bites or strikes.

That's 70 deaths a year caused by dogs, compared with 1.3 deaths caused by sharks. The difference is more than 50-fold, and our first famous predator is already out.

But sharks aren't the only feared animals to lose early.

We might think of venomous snakes and lizards as obvious contenders, yet they caused an average of just five deaths annually. Deaths caused by bees, wasps, and hornets? Nearly 83. That means these everyday stinging insects killed more than 16 times as many Americans as venomous snakes and lizards. A sting might seem harmless to most of us, but for someone with a severe allergy, it can quickly become life-threatening.

Spiders don't fare better either. Over the six years 2018-2023, venomous spiders caused just 26 deaths. The broader category of other mammals, which includes animals such as cattle and horses, accounted for 458 deaths during the same period. That's roughly 76 deaths a year, compared with just four from spiders.

Then comes a much smaller contender with a surprisingly deadly bite. Mosquitoes can spread West Nile virus, which caused 807 reported deaths in the United States between 2018 and 2023, according to the CDC. That's an average of nearly 135 deaths every year. By comparison, other specified venomous arthropods accounted for 78 deaths over the same six years, averaging just 13 annually. West Nile virus takes the final spot in the semifinals, alongside dogs, stinging insects, and other mammals. And with the highest death toll among the four, it looks like the strongest contender yet.

But there's still a long way to go before we crown a winner.

Now that dogs have knocked out sharks, only to lose to bees, wasps, and hornets. Meanwhile, West Nile virus pushes past larger mammals, including cattle and horses.

That leaves two unlikely contenders: stinging insects and a disease spread mainly by mosquitoes. West Nile virus comes out ahead, making mosquito-borne disease the deadliest threat in our bracket so far.

But there's one final challenger we haven't considered yet. And millions of Americans encounter this danger every time they drive.

The final challenger isn't a predator lurking in the wild. It's an animal crossing the road. According to the Insurance Institute for Highway Safety, collisions involving animals killed 1,164 Americans between 2018 and 2023. That's an average of 194 deaths a year, considerably more than the nearly 135 deaths annually from West Nile virus.

In 2024 alone, another 210 Americans lost their lives in crashes involving animals. So, animal-related road crashes take the top spot in our bracket.

Not quite. Deer are involved in many serious road crashes, especially in areas where highways cross forests and farmland. An earlier IIHS study examining 147 fatal animal crashes across nine states found that deer accounted for 77% of the animals struck.

But the study covered 2000–2002. More importantly, the federal crash data used for our recent totals doesn't identify the animal involved in each collision. The 194 deaths per year therefore include crashes involving deer and other animals, not deer alone.

There's a similar limitation with some of our other contestants. The CDC groups cattle, horses, and other mammals together, so we cannot attribute the entire category to cows. Our results identify the winner among the nine animal-related threats we compared. They don't prove that any single animal species kills more Americans than every other species.

Deer become more active during their autumn mating season, with collisions particularly common in October and November. Drivers should be especially alert around dawn and dusk, when deer are more likely to be moving near roads.

One important safety recommendation from state wildlife authorities is to avoid swerving if a deer suddenly crosses your path. Brake firmly and stay in your lane rather than risking a collision with another vehicle or roadside object.

We compared nine selected animal-related threats using average annual U.S. deaths from 2018 through 2023.

Direct encounter deaths come from Langley and Kearney's 2025 study, which analyzed CDC WONDER underlying cause-of-death records using ICD-10 codes W53–W59 and X20–X29. Road fatalities come from the Insurance Institute for Highway Safety (IIHS), using federal Fatality Analysis Reporting System data. West Nile virus deaths come from CDC surveillance, while shark fatalities come from the International Shark Attack File and its annual reports.

The sources measure different types of fatalities. Road collisions can involve different animal species, while West Nile virus is only one of several mosquito-borne diseases. These death counts do not represent an individual's probability of dying from an animal encounter.

Some animal categories, including alligators and crocodiles, were excluded because their death counts were suppressed in the CDC-based study due to small numbers.

The bracket is our editorial comparison of selected threats, not a complete ranking of all animal species or animal-associated diseases.