Celebrating World Polio Day

Children using an iron lung, a device used to help those with severe polio cases breathe. ‘Two patients are treated in full-body respirators called iron lungs.” March of Dimes Foundation, https://www.pbs.org/wgbh/americanexperience/features/polio-crusade/

October 24th is World Polio Day, so let us go back in time, covering the history of polio and global efforts to eliminate and protect against it.

What is Polio?
Polio, short for poliomyelitis, is an illness caused by a poliovirus that primarily targets nerves in the spinal cord or brainstem. Though the pain and terror caused by polio during the 20th century, most people infected with polio will be asymptomatic. However, polio, like many other viruses, can be spread through sneezing or coughing. It can also be spread through feces and its contaminated water.

There are 3 main categorizations of polio:

Abortive polio: affecting about 5% of all poliovirus infections, this type causes flu-like symptoms, such as: fever, sore throat, loss of appetite and muscle aches. These symptoms generally last for 2-3 days on end.

Nonparalytic polio: affecting about 1% of infections, is much more serious and deadly than abortive polio. It initially begins as flu-like symptoms, along with some stiffness in the neck, arms or legs and headaches. Should it progress, a second phase of symptoms arise, with more stiffness, weaker muscles and the decreasing of reflexes which leads into the final, and most deadly form of polio.

Paralytic polio: one of the rarest forms of polio, which as the name suggests, starts as nonparalytic polio before progressing. Symptoms can include: intense pain, muscle spasms, further muscle weakness, and paralysis of muscles that help with breathing. In this form, individual limbs experience paralysis or deformities, and an iron lung was used in the past to assist with breathing.


Polio: A Blast From the Past
Though polio really first made its mark during the 1910’s - 1920’s and onwards, evidence of the disease dates back to Ancient Egypt. One of the first recorded polio cases is said to be a priest, recorded on the stele from 1365 to1403- BC, with the classic leg deformities that Polio can bring to a person. Even with this, the first clinical description of polio was made in 1789 by London Pediatrician Michael Underwood, describing its symptoms in infants. Despite the evidence of polio’s existence and spread, only sporadic cases were documented, mainly throughout industrialized countries. It’s still debated why this is, whether the cleaner conditions stopped natural immunization, or whether, overtime, better diagnosis tools came out, allowing for more cases to be determined. 51 years later, Dr Jacob von Heine conducted the first real investigation of polio, developing a theory that it may be contagious. This was right before one of the first real epidemics of the disease, with 14 people near Oslo, Norway being infected. From there, new epidemics soon arose, with about 132 cases in Vermont in 1894, and about 1031 in Sweden in 1905. This is also around the time that Swedish Paediatrician Dr. Ivar Wickman recognized that polio could very easily spread from the infected to the uninfected without proper quarantine measures. Another epidemic soon arose in Sweden yet again in 1911, with double the cases of the last, and 3840 in Stockholm. Here, professor Carl Kling and his colleagues managed to do a test on some victims and discovered polio in their throat (and sometimes small intestines). Even with all this research, a new outbreak was just around the corner.

Spreading Like Wildfire
Though a lot of polio outbreaks were first recorded in Scandinavia, epidemics in North America were annually reported. During the 1910’s, it was known as a season, a time period where parents would monitor their kids closely, attempting to catch polio symptoms early. Most polio infections at this time were in young children, often infants. In June of 1916 however, the US got its first major polio outbreak. In Pigtown, New York, polio began to spread like wildfire, with the community closing down to outsiders and patrolling train stations and roads. The city's outbreak lasted through October, killing 6,000 and leaving 27,000 paralyzed. In New York City, about 8,900 cases were reported and 2,400 deaths, 80% of which were children. Similar epidemics soon began to arise in the country, and even made its way over to Canada. Though this period saw numerous deaths and paralyzations, the worst time for polio outbreaks was actually the 1940’s to 1950’s, otherwise known as the WW2 era.

At this time, experts began to realize that not only were the cases of polio (specifically paralytic) going up, but the age at which people got infected was increasing as well, now affecting those over the age of 10. From 1940 to1944, polio cases sat at about 8 per 100,000, doubling in 1945 and peaking in 1952, with over 57,000 cases country wide. In 1953 Canada saw 9,000 cases and 500 deaths altogether. Oftentimes schools, playgrounds, and movie theatres had to be officially closed down during various regional epidemics. Additionally, cases of nurses coming out of retirement just to help with the epidemic increased. Many children suffering with polio came to various Sick Kids hospitals in the country, especially in Toronto. Here, homemade iron lungs were put together using parts found in the hospital's basement, as health officials and the government struggled to meet demand. In the end, the hospital was able to construct roughly 27 makeshift iron lungs within the span of weeks. For these people, children, and families, though all seemed quite troubling, help was around the corner.


Vaccines and Solutions


The inactivated polio vaccine, also known as “Salk vaccine”, is being drawn. “Inactivated poliovirus vaccine”Polioeradicaiton, https://polioeradication.org/about-polio/the-vaccines/ipv/.


With over half a million people paralyzed each year, and 3 rapidly spreading strains of wild poliovirus, vaccines became the main solution for this issue. The first real breakthrough came in 1949 and 1952, with John Enders, Thomas Weller and Frederick Robbins successful poliovirus cultivation in tissue, and Dorothy Horstmann’s experiments confirming poliovirus in blood. Both these discoveries helped the 1950’s vaccine creation, made by physician Jonas Salk. This version of the vaccine included an inactive (or “killed”) version of the virus, and was tested on himself, his family, and various others spanning the US, Canada and Finland. On April 12th 1955, it was officially licensed, now being created by six pharmaceutical companies. However, it was not patented, as he didn’t want to profit off of the elimination of polio. A second vaccine, this time oral, was made by physician and microbiologist Albert Sabin. This vaccine gave the virus a very weakened state. Though Salk's vaccine was favoured in the US, the convenience that an oral vaccine brought helped thousands, as it was tested and later given to children in the Soviet Union, Czechoslovakia from 1958 to1959. Unlike the inactive vaccine, this one could actively stop the spread and transmission of the virus. Czechoslovakia later became the first country to rid polio entirely in the early 1960’s. In 1988, the World Health Assembly created and passed resolutions to eradicate polio, with the Global Polio Eradication Initiative (GPEI) also being launched. With their assistance, vaccines (both Salks and Sabins) were distributed globally. By 1994, polio was eradicated from both Americas and by 1999, type 2 of wild poliovirus was completely eradicated. By 2003, polio was endemic in 6 countries, dropping further to 4 in 2006. The WHO’s South-East Asia region became polio free in 2014, with the African region meeting that goal in 2020. In the same year, wild poliovirus type 3 was also eradicated.

As of 2022, cases of polio are far and few inbetween, with 22 cases being recorded, and the virus endemic in only 2 countries; Afghanistan and Pakistan. They are one of the last places on earth where type 1 of the virus is still found.

Vaccinations
Though it's still recommended that travellers going to these areas get booster vaccinations, the successful near-eradication of polio shows the vaccine's effectiveness in dire situations and how the lives of many can be improved by a single dose.