August is National Immunization Awareness Month (NIAM) in America – an ideal time to learn (or review!) our work in eradicating diseases, and some of the current challenges facing vaccination.
Smallpox – eradicated in 1980
The #1 fear in America today is public speaking, but back in the 20th century, it was probably smallpox. About 1 in 3 people who were infected died from the disease.
With chances like those, it’s no wonder smallpox was one of the most devastating diseases known to mankind, but that all changed in the space of 10 years. In 1967, a historic campaign was launched by the World Health Organization (WHO). The aim? To eradicate smallpox from the face of the earth.
High levels of global vaccination coverage were achieved by tediously seeking out active cases and vaccinating ALL their contacts. The last cases of smallpox were reported in 1977, and global eradication was declared in 1980.
Polio – Ongoing Eradication…
The 1950’s weren’t all Frank Sinatra & Marilyn Monroe. The unsanitary conditions of the time made polio a global threat. Many lived in fear of the potentially fatal paralysis that might follow.
That’s why the whole world rejoiced when Jonas Salk revealed his polio vaccine in 1955. The oral polio vaccine (OPV) followed shortly after in 1961, because of how easy to administer and inexpensive it was, it became instrumental for polio eradication. The global effort to eradicate polio was launched in 1988, and to date, it has resulted in a 99.99% reduction in polio cases (From 350,000 in 1988 to just 13 this year!).
Today, polio remains a significant problem in Afghanistan, Nigeria and Pakistan – areas affected by conflict and poor sanitation. Conquering polio is a human rights issue, and this is where the final stage of the eradication campaign is focused.
Challenges for vaccination
Breaking Chains of Infection
Once you have a working vaccine it seems like the hard work is over, right? I like to reflect on a quote by vaccine advocate and leading microbiologist Dr. Samir Saha, “it is not a vaccine that prevents disease, it is vaccination that does.” The challenge remains that people must be mobilized to get themselves and their kids vaccinated.
How vaccines can stop the spread of infection can be explained by a quick math lesson. The R0 of an infectious disease is the average number of infections that one infected individual can cause over the course of the disease cycle in a population with no immunity to the disease. Measles, a highly infectious disease, has an R0 of 12-18 per case! When R0 is less than 1, it means each case of disease is not really causing new cases. Vaccines are our tool to break down the R0 and end this chain of infection (for more on the math, look here). But, some people are either too young for vaccines, or have medical exemptions (for example, allergies or immune deficiencies). These people rely on communities of vaccinated people to break infection chains to keep themselves safe from disease – it’s the only barrier they have! This protection is known as herd immunity, here’s how it works:
Outbreaks of Previously Eliminated Disease
Americans celebrated the elimination of measles from their country in the year 2000, but behind the scenes, non-medical vaccine exemptions (NMEs) were increasing. Parents can get NMEs for their children based on either religious or personal beliefs. But why would parents do this? The rise in NMEs across America is likely due to the misinformation spread by the anti-vaxx community, which provokes fear and hesitancy.
“Fear leads to hate, hate leads to anger, anger leads to suffering” – Yoda
As a result, in 2014, a devastating measles outbreak occurred at Disneyland in California. This outbreak was attributed to the large number of unvaccinated children visiting the park, which made it all too easy for measles to spread. This outbreak caused 179 cases of measles across 21 states, and unfortunately, this included 12 children who were too young to be vaccinated.
So how can we avoid more outbreaks like this?
How can we protect ourselves?
Vaccination has saved more lives than any other scientific discovery in history (check out this infographic).However, if we become complacent in getting vaccinated, previously eliminated diseases will return.
Several states in America have made progress by getting serious about vaccination. California, West Virginia, and Mississippi have banned all non-medical vaccine exemptions, arguing that, “Parental duties trump parental rights.” There’s still plenty of work to do, as religious exemptions are still available in most states and personal exemptions are available in at least 18.
Perhaps we can avoid more outbreaks by:
- Making it easier to receive vaccinations
- Making non-medical exemptions more difficult
- Strengthening or changing laws to improve vaccine uptake
- Improving vaccine knowledge of healthcare providers
- Fighting misinformation
This article covers some of the milestone progress made by vaccines. To learn about the myriad of benefits vaccines have over economies, human rights, and more, check out this vaccine advocacy tool.
Have any other ideas? We’d love to hear them!
Until next time, stay safe & vaccinate.