If we were tasked to choose the single most important health-related innovation from the past 100 years, we could make a very strong case for vaccines. After all, immunization has saved countless millions of lives and prevented endless suffering around the world.
In recognition of this fact, Canada celebrates National Immunization Awareness Week from April 23 to 30 this year. It’s a good reminder of the value of this now-obvious advance.
A century ago, infectious diseases were the leading cause of death worldwide. Today, they now cause fewer than 5% of all deaths — thanks to immunization programs.
Immunization protects us by preventing the spread of disease; as more people are immunized, the risk is reduced for everyone. That makes immunization the single most cost-effective health investment and an important cornerstone of the health system.
As we look back over the history of vaccines, certain milestones pop up. We might start in 1798 with the demonstration by Edward Jenner that inoculation with cowpox could protect against smallpox. This brought the first hope that the disease could be controlled. Progress was slow but by 1885 a Dr. Stewart in Palmerston, Ontario had established a vaccine farm and his cows provided a dependable smallpox vaccine supply for the next 31 years until 1916 when Connaught Laboratories took over the manufacture of sterile vaccine.
The Pertussis (whooping cough) bacterium was identified in 1906 and by 1918, the first Canadian vaccine was introduced. In 1953 there were 9,000 cases of polio reported. Then came the polio vaccine and just 12 years later, only three cases were reported. Moving to 2006, the first HPV (human papilloma virus) vaccine was approved for use in Canada to reduce the risk that women will develop cervical cancer. And in 2008, the shingles (herpes zoster) vaccine was approved for Canadian use.
Despite these life-giving changes to health care, there will always be people denying the validity of immunization. That should not surprise as there have been anti-vaccine campaigns since vaccination began in the late 18th century.
The problem with this is that when public confidence in the effectiveness and safety of a vaccine becomes widespread, the result can be severe. Diseases can quickly return when fewer people are immunized. This has been demonstrated on countless occasions: think of the measles outbreaks in 2014 in southern Alberta and the Fraser Valley.
Because of the immense success of immunization, we tend to forget that it was mass vaccination that helped eradicate smallpox, and polio, and has made other diseases rare or even invisible to most of us.
Consider the long list of diseases that can be prevented by routine vaccination and ask yourself, would you have any recur? It’s a long list: diphtheria, influenza, Hepatitis A and B, shingles, human papilloma virus (HPV), measles, meningococcal disease, pertussis, mumps, pneumococcal disease, polio, rotavirus, rubella, tetanus, chickenpox.
Immunization has been so successful in eliminating diseases that many of us have become disconnected from the threat. We cannot forget how easily a disease can re-establish itself.
Dr. Paul Martiquet is the Medical Health Officer for Rural Vancouver Coastal Health including Powell River, the Sunshine Coast, Sea-to- Sky, Bella Bella and Bella Coola.