From Smallpox to Polio: The Deadly Diseases Gen Z Never Had to Fear Thanks to Vaccines

For much of human history, infectious diseases shaped entire generations - causing widespread death, disability, and fear. Today, however, many of these once-devastating illnesses are rarely seen, especially among Gen Z. And even if you fall once in a while, the intensity of infections is not as high as it used to be. However, according to experts, this transformation did not happen by chance. It is the result of decades of global vaccination efforts. Vaccines have fundamentally reshaped public health, preventing millions of deaths and reducing the burden of infectious diseases worldwide. "Vaccination remains one of the most effective, evidence-backed interventions in preventive healthcare. It significantly reduces the burden of infectious diseases and their

complications. Vaccines are focused on strengthening preventive care by driving awareness around vaccine-preventable illnesses and improving access to essential immunization services,” said Gaurav Verma, Chief Business Officer at PharmEasy (API Holdings).Also read: Ajay Rai Hospitalised After Fainting - Low Sodium Levels Trigger Health Scare

Diseases that vaccines can ward off

Here’s a closer look at the major illnesses Gen Z has largely been shielded from - thanks to immunisation.

Smallpox – the only eradicated human disease

Smallpox was once one of the deadliest diseases known to humanity, responsible for millions of deaths over centuries. Through a coordinated global vaccination campaign, it became the first and only human disease to be completely eradicated in 1980. Today, younger generations have never encountered it outside of history books.

Polio: From paralysis to near elimination

Polio once paralysed thousands of children every year. With the introduction of effective vaccines in the mid-20th century, cases have dropped dramatically. While not fully eradicated, polio is now confined to a few regions, making it a rare disease for most of the world.

Measles: A once-common childhood killer

Before vaccination, Measles outbreaks were frequent and often fatal, particularly among children. Since the vaccine’s introduction in 1963, global cases have declined significantly, although occasional outbreaks still occur where vaccination rates drop.

Mumps: Reduced but not forgotten

Mumps caused painful swelling and complications such as hearing loss. The introduction of the MMR (measles, mumps, rubella) vaccine has greatly reduced its prevalence, making it uncommon among vaccinated populations.

Rubella: Protecting mothers and babies

Rubella, or German measles, posed serious risks during pregnancy, leading to miscarriages and congenital disabilities. Vaccination has significantly reduced cases and protected millions of newborns from lifelong complications.

Hepatitis B: Preventing chronic disease

Hepatitis B can lead to chronic liver disease and even cancer. Since the introduction of its vaccine in the 1980s, infection rates have dropped sharply, particularly in countries with strong immunisation programmes.

Haemophilus influenzae type b (Hib): A silent threat

Haemophilus influenzae type b once caused severe illnesses like meningitis in children. Vaccination has drastically reduced cases, preventing thousands of deaths and disabilities annually.

Tetanus: Rare but still preventable

Tetanus, caused by bacteria entering wounds, leads to painful muscle stiffness and can be fatal. While the bacteria still exist in the environment, vaccines have made the disease rare in many parts of the world.

Why is vaccination important?

Despite these successes, vaccines remain crucial. Diseases like measles and polio can resurface if immunisation rates fall. Public health experts stress the importance of maintaining high vaccination coverage to prevent outbreaks and protect vulnerable populations. The fact that Gen Z has grown up without facing these deadly diseases is one of the greatest achievements in modern medicine. Vaccines didn’t just reduce illness; they changed what it means to live a healthy life.