Key figures
- Mosquitoes top the chart at 725,000 human deaths a year, mostly through the diseases they carry.
- Humans come second at 475,000 deaths a year.
- Snakes kill 50,000 people a year and dogs 25,000, which the graphic attributes to rabies.
- Sharks and wolves are at the bottom with 10 deaths a year each; lions and elephants kill 100 each.
All figures are from the graphic, made for Bill Gates’s GatesNotes in 2014, which cites the WHO and other sources and says all calculations have wide error margins.
Human deaths by animals in text
Title: World’s Deadliest Animals. Subtitle: Number of people killed by animals per year. Column key: Number of deaths, Killer. The chart is drawn from smallest to largest, ending with two large blocks for humans and mosquitoes; the table below lists it from largest to smallest.
| Rank | Animal | People killed per year | Disease named on the graphic |
|---|---|---|---|
| 1 | Mosquito | 725,000 | |
| 2 | Human | 475,000 | |
| 3 | Snake | 50,000 | |
| 4 | Dog | 25,000 | rabies |
| 5 | Tsetse fly | 10,000 | sleeping sickness |
| 6 | Assassin bug | 10,000 | Chagas disease |
| 7 | Freshwater snail | 10,000 | schistosomiasis |
| 8 | Ascaris roundworm | 2,500 | |
| 9 | Tapeworm | 2,000 | |
| 10 | Crocodile | 1,000 | |
| 11 | Hippopotamus | 500 | |
| 12 | Elephant | 100 | |
| 13 | Lion | 100 | |
| 14 | Wolf | 10 | |
| 15 | Shark | 10 |
Footer: “Sources: WHO; crocodile-attack.info; Kasturiratne et al. (doi.org/10.1371/journal.pmed.0050218); FAO (webcitation.org/6OgpS8SVO); Linnell et al. (webcitation.org/6ORL7DBUO); Packer et al. (doi.org/10.1038/436927a); Alessandro De Maddalena. All calculations have wide error margins.”
Why mosquitoes kill the most people
Bill Gates published this chart during “Mosquito Week” on GatesNotes in April 2014. He wrote that mosquitoes carry the most damaging diseases, the worst being malaria, which he said then killed more than 600,000 people a year, alongside dengue, yellow fever and encephalitis [1]. He also noted that sharks kill fewer than a dozen people a year, while mosquitoes kill 50,000 times as many [1].
The WHO’s latest figures are close to the chart’s malaria share. It estimates 282 million malaria cases and 610,000 malaria deaths in 2024, with the WHO African Region accounting for 95% of deaths and children under 5 for about 75% of deaths in that region [2].
Snakes and dogs
The WHO estimates that 81,410 to 137,880 people die each year from snake bites, and about three times as many suffer amputations or other permanent disability [3]. That is above the chart’s 50,000.
Dogs appear on the chart because of rabies. The WHO says rabies causes tens of thousands of deaths a year, mainly in Asia and Africa, that 40% of victims are children under 15, and that dog bites and scratches cause 99% of human rabies cases [4]. One model it cites puts the toll at 44,203 deaths a year, and the WHO notes the true number is uncertain because cases are underreported [4].
Notes on this infographic
- The figures date from 2014 and the graphic itself warns of wide error margins.
- Updated WHO estimates differ for some animals: snakebite deaths of 81,410 to 137,880 a year against the chart’s 50,000 [3], and rabies at an estimated 44,203 a year against 25,000 for dogs [4].
- Most of the deaths on the chart are from diseases, not attacks. Mosquitoes, tsetse flies, assassin bugs and freshwater snails carry parasites or viruses, and the dog figure is rabies.
- The human figure counts people killed by other people.
Questions about deaths caused by animals
What animal causes the most human deaths?
The mosquito, with 725,000 deaths a year on the chart, mostly from the diseases it spreads. Malaria alone caused an estimated 610,000 deaths in 2024, according to the WHO [2].
How many people die from animal attacks each year?
The chart does not split attacks from disease. Its largest attack-type figures are 50,000 for snakes and 1,000 for crocodiles, while the WHO now estimates 81,410 to 137,880 snakebite deaths a year [3].
How many people do dogs kill a year worldwide?
25,000 a year on the chart, which labels the dog figure as rabies. The WHO says dogs cause 99% of human rabies cases and cites an estimate of 44,203 rabies deaths a year [4].
Sources
- Bill Gates, The Deadliest Animal in the World, GatesNotes, 25 April 2014 (archived copy). The original post of this graphic.
- World Health Organization, Malaria fact sheet.
- World Health Organization, Snakebite envenoming fact sheet.
- World Health Organization, Rabies fact sheet.
Last reviewed 30 October 2026
