How Many Diseases are Preventable by Vaccines?

The power of vaccines cannot be underestimated. Take, for example, Poliomyelitis– a significant problem 70 years ago  – and is now close to becoming a disease of the past. Not that long ago, smallpox was completely eradicated through the use of a vaccine. 

As the world celebrates the imminent arrival of several COVID-19 vaccines, we might ask how many diseases are preventable by vaccines as of 2020.

Diphtheria, Flu, Hepatitis, and Tetanus, Oh My!

There are 29 infectious diseases that are vaccine-preventable and recognized by the World Health Organization. Included in that 29 are what most people know as the main vaccine-preventable diseases like diphtheria, hepatitis B, measles, and more. Vaccines prevent millions of deaths each year and have even helped eradicate some diseases from communities. The disease list on the World Health Organizations site includes:

• Cholera
• COVID-19
• Dengue Fever
• Diphtheria
• Ebola
• Haemophilus influenzae type B
• Hepatitis A, B, and E
• Human Papillomavirus (HPV)
• Influenza (flu)
• Japanese Encephalitis
• Malaria
• Meningococcal Disease
• Mumps
• Pneumococcal Disease
• Pertussis (Whooping Cough)
• Poliomyelitis (Polio)
• Rabies
• Rotavirus Gastroenteritis
• Rubella
• Tetanus
• Tick-born Encephalitis
• Tuberculosis
• Typhoid Fever
• Varicella
• Yellow Fever
• Shingles (Herpes Zoster, also caused by Varicella-Zoster)

In fact, vaccines have also helped curb the occurrence of certain types of diseases in animals as well. Diseases prevented by vaccines in animals include:

• Bordetella
• Canine Distemper
• Canine Influenza
• Canine Parvovirus (Parvo)
• Chlamydia
• Feline Calicivirus
• Feline Distemper
• Feline Leukemia
• Feline Viral Rhinotracheitis
• Leptospirosis (Lepto)
• Lyme Disease

Health care providers often encourage vaccines because of the tremendous impact immunization has on community health and illness prevention. From flu shots to immunizations for tetanus, most people have had or will have some type of vaccination in their lives. However, not every disease can be curbed with immunization.

Which Disease Hasn’t Got a Vaccine Yet?

Of the 361 generic infectious diseases that affect humans, only 62 (17%) are preventable by vaccines. Over 100 of the remainder are caused by fungi and parasites – from malaria to scabies, and from ringworm to candidiasis. Developing vaccines against these pathogens is more complicated than working with viruses or bacteria, but scientists are making good progress.

Hope on the Horizon

Other notable diseases awaiting vaccines are caused by viruses, such as HIV, Chikungunya, Norovirus, and Zika virus, and bacteria – syphilis, leprosy, and bacillary dysentery. These diseases affect millions of people each year, incurring significant treatment and care costs for those affected and society.

The good news is that most of these diseases already have developed vaccines. Preventing any of the mentioned diseases would be a huge success and help ease the global strain on healthcare professionals, supplies, and equipment.

The burden of proof and regulation of vaccines can take years of evidential trials, funding allocation, and medical board approval (FDA in the United States), which makes progress appear painfully slow. But these processes are necessary to ensure that putting it into our bodies is safe and effective.

We remain grateful for the hard work of scientists in developing vaccines to keep us safe.