When you hear the phrase “top 10 infectious” you probably think of current outbreaks, but history is littered with victories where science and determination knocked out some of the world’s nastiest bugs. From the scourge of smallpox to the relentless mosquito that spreads malaria, humanity has turned the tide on diseases that once threatened entire continents. Below is a lively rundown of the ten most remarkable infectious defeats, complete with the stories, the heroes, and the breakthroughs that made them possible.
Why the Top 10 Infectious Victories Matter
These triumphs aren’t just footnotes in a medical textbook; they are proof that coordinated global action, relentless research, and clever public‑health strategies can erase even the most terrifying pathogens. Let’s dive into each conquest, starting with the disease that claimed more lives than any other.
10 Smallpox
Smallpox was a ruthless airborne virus that claimed about one‑third of every person it infected. With no cure in sight, physicians could only watch a two‑week waiting game to see who would survive; those who did were left with the unmistakable, scar‑filled pockmarks that gave the disease its name.
In 1796, English doctor Edward Jenner observed that milkmaids who had previously caught cowpox never seemed to contract smallpox. To test his hunch, he inoculated the eight‑year‑old son of his gardener with cowpox and later exposed the boy to the deadly smallpox virus. Remarkably, the youngster remained healthy – Jenner had unintentionally created the world’s first vaccine.
Jenner’s breakthrough dramatically cut smallpox deaths. By the time the World Health Organization (WHO) launched an eradication campaign in 1959, the disease was largely confined to South America, Africa, and Southeast Asia.
WHO orchestrated massive vaccine drives and guided nations on proper administration. The final known case surfaced in Somalia in 1977, and in 1980 the organization proudly declared smallpox the first disease ever eradicated by human effort.
9 Rinderpest
Rinderpest, often called “cattle plague,” never infected humans, yet its impact on livestock was catastrophic. In the 1890s, the virus wiped out 80‑90 % of cattle across sub‑Saharan Africa, leaving farmers without meat, milk, or draft animals and causing a population drop of at least one‑third in the affected regions.
Any animal that survived the infection developed lifelong immunity, and the high mortality rate meant that wild hosts such as buffalo and giraffes were also decimated before they could transmit the virus to domestic herds.
In the 1960s, British scientist Walter Plowright engineered a vaccine, which the United Nations Food and Agriculture Organization began purchasing in bulk during the 1990s. Veterinarians across Europe, Asia, and Africa vaccinated cattle worldwide, finally eradicating rinderpest in 2011 – the second disease ever to be wiped out.
8 Polio
Polio, short for poliomyelitis, is a virus that can cause temporary or permanent paralysis, and in severe cases it attacks the lungs, leading to death.
In 1953, Jonas Salk announced he had created a safe polio vaccine and deliberately refused to patent it, ensuring the serum could be distributed as widely as possible – a decision that cost him billions in today’s dollars.
The March of Dimes funded a massive trial, and by 1979 the United States was declared polio‑free, just 24 years after the vaccine’s introduction. The WHO’s Global Polio Eradication Initiative, launched in 1988, has driven a 99.99 % drop in cases, leaving the disease endemic only in Afghanistan, Pakistan, and Nigeria.
7 Guinea Worm
When a person drinks stagnant water teeming with Guinea worm larvae, the parasites travel to the intestines, mature, and after 10‑14 months a female worm migrates to the lower limb, forming a painful blister that forces the host to dunk the foot in water, releasing new larvae back into the source.
Although the lesions are excruciating and can become infected, the disease is rarely fatal. Still, no one enjoys having worms reproducing inside their bodies.
The Carter Center has spearheaded a water‑purification campaign that has been wildly successful. In 1986, an estimated 3.5 million cases plagued South Asia, Yemen, and sub‑Saharan Africa; by 2018, only 28 cases were reported worldwide.
6 Yaws
Yaws, also known as frambesia, spreads through skin‑to‑skin contact with the bacterium Treponema pallidum pertenue. Within three months of infection, patients develop raspberry‑like lesions, especially on the face, which fade after six months but may recur later, often leaving disfiguring scars that can lead to bullying.
In the 1950s, yaws affected over 70 countries. Because a single dose of the antibiotic azithromycin can cure it, WHO targeted the disease early on for eradication. Efforts in the 1960s nearly eliminated it, but attention shifted to smallpox, and yaws lingered.
As of 2019, the disease still persisted in 15 nations, reminding us that vigilance is essential even after major successes.
5 Hookworm
Hookworms thrive in soil contaminated by sewage and penetrate the skin, usually through bare feet. Once inside, they travel to the small intestine where they feed on the host’s blood, causing fatigue, anemia, bloating, and stunted growth.
Because they live where sanitation is poor, infected individuals often excrete the worms, contaminating the ground again and perpetuating the cycle of infection.
In 1910, philanthropist John D. Rockefeller Sr. donated $1 million to a campaign aimed at eradicating hookworms in the American South. The five‑year effort dramatically lowered infection rates and boosted school attendance, as children were no longer drained of energy by the parasites.
Although near‑elimination has been achieved, reinfection remains common. The Human Hookworm Vaccine Initiative is now developing a drug that blocks the worm’s ability to feed, promising a future where hookworms could finally disappear.
4 Measles
Measles has made a modest comeback in recent years as vaccination rates slipped, yet the global burden has plummeted over the past half‑century.
Before 1963, virtually every American child contracted measles by age 15, with major epidemics every two to three years and an average of 2.6 million deaths annually worldwide. The virus spreads through coughing and sneezing.
In 1954, Harvard’s Dr. Thomas C. Peebles asked 11‑year‑old patient David Edmonston if he wanted “to be of service to mankind.” Edmonston consented, allowing Dr. John F. Enders to isolate the virus and develop the Edmonston‑Enders vaccine, which remains in use today.
From 2000 to 2018, measles deaths fell 73 %, saving an estimated 23.2 million lives. The United States declared measles eliminated in 2000, yet 1,282 cases were still reported in 2019, underscoring the need for continued immunization.
3 Tetanus
Tetanus is caused by the bacterium Clostridium tetani, which resides in soils worldwide. When it enters an open wound, the microbe releases a toxin that induces painful muscle spasms and can cause paralysis.
Because the bacterium is heat‑ and chemical‑resistant, eradication is unlikely, but widespread vaccination has effectively eliminated new cases in many regions.
In 1990, roughly 314,000 people died from tetanus globally. By 2017, deaths had dropped to 38,000 – an 88 % reduction – with the highest burden still found in South Sudan and Somalia.
2 Elephantiasis
Elephantiasis stems from three species of threadlike worms that lodge in the lymphatic system, impairing fluid regulation and causing limbs or genitals to swell to elephant‑like proportions.
The infected worms release larvae into the bloodstream; when a mosquito bites an afflicted person, it can transmit the disease to subsequent victims.
Medications can treat the infection, and combined with mosquito‑prevention measures, the spread can be halted.
Since 2000, more than 7.7 billion treatments have reached over 910 million people. Sixteen countries have eliminated the disease, with seven additional nations under surveillance for possible eradication.
1 Malaria
Malaria is driven by a tiny blood parasite transmitted by Anopheles mosquitoes. Symptoms range from fever and chills to severe headache, nausea, and body aches.
The disease has plagued Europe, Africa, and Asia for centuries. When Europeans colonized the Americas, malaria rode along, exposing an estimated 53 % of the world’s landmass to infection at its peak.
In the early 1900s, understanding of mosquito‑borne transmission led to massive public‑health actions: draining wetlands, widespread insecticide spraying, and the creation of the Office of Malaria Control in War Areas, which later evolved into the Centers for Disease Control.
The 21st century has seen remarkable progress. Between 2000 and 2015, malaria deaths fell from 840,000 to 440,000 annually, with most fatalities occurring among African children.
Continued innovation, from rapid‑diagnostic tests to novel antimalarial drugs, keeps the momentum going as the global community strives to push the disease toward eventual eradication.