Logan Reed
The first polio vaccine, developed by Jonas Salk, arrived at the Mayo Clinic on April 13, 1955, one day after it was licensed in the US. However, the process of inactivating the live virus proved defective, causing 40,000 cases of polio and leading to the Cutter Incident, which opened the floodgates to a wave of litigation. This resulted in the National Vaccine Injury Compensation Program in 1986. Today, the inactivated polio vaccine (IPV) is the only polio vaccine administered in the US, offering 99–100% protection against the disease. However, the oral polio vaccine (OPV), which is no longer licensed in the US, can, in rare cases, mutate into a form that causes disease in under-vaccinated populations.
| Characteristics | Values |
|---|---|
| Date of first polio vaccine | 12 April 1955 |
| Creator of the first polio vaccine | Jonas Salk |
| Type of first polio vaccine | Inactivated polio vaccine (IPV) |
| Number of children vaccinated in the first mass vaccination programme | 200,000 |
| Number of cases of polio caused by the first polio vaccine | 40,000 |
| Number of children left with varying degrees of paralysis due to the first polio vaccine | 200 |
| Number of deaths caused by the first polio vaccine | 10 |
| Replacement polio vaccine creator | Albert Sabin |
| Type of replacement polio vaccine | Oral polio vaccine (OPV) |
| Year OPV came into commercial use | 1961 |
| Year polio was eliminated in the US | 1979 |
| Year polio was eliminated in the Western Hemisphere | 1994 |
| Number of cases of wild poliovirus recorded globally as of July 2021 | 2 |
Explore related products
The Cutter Incident
On April 12, 1955, the success of Jonas Salk's polio vaccine trial was announced, and Cutter Laboratories was one of several companies recommended to be licensed by the US government to produce the vaccine. However, despite passing the required safety tests, some batches of the Cutter vaccine contained a live poliovirus, which was supposed to be inactive. On April 27, Cutter withdrew its vaccine from the market after vaccine-associated cases were reported. This incident, known as the Cutter Incident, resulted in 40,000 cases of polio, with 200 children suffering varying degrees of paralysis and 10 deaths.
Vaccine Status: Second Shot — Fully Vaccinated?
You may want to see also
Explore related products
Salk vs Sabin
In the 1950s, Jonas Salk and Albert Bruce Sabin developed separate vaccines to combat polio, a highly infectious disease that mostly affects young children and can lead to paralysis and death. The Salk vaccine was made with a killed virus, while the Sabin vaccine was made with a live but weakened virus.
The Salk vaccine, or inactivated polio vaccine (IPV), was the first polio vaccine to be approved, in 1955. It was produced on a large scale with the assistance of several well-known pharmaceutical companies. By 1961, annual polio cases in the US had dropped from 58,000 to 161. Salk was committed to equitable access to his vaccine and did not profit from sharing its formulation.
The Sabin vaccine, or oral polio vaccine (OPV), was introduced in the United States in the 1960s and replaced the Salk vaccine. OPV was easier to administer than IPV as it did not require sterile syringes, and it provided longer-lasting immunity. It was also more suitable for mass vaccination campaigns and did not need to be kept cold. Sabin conducted large-scale trials of his vaccine in the Soviet Union, where it was approved for manufacture in 1961.
While both vaccines were successful in bringing polio under control, the science behind them has fuelled a debate that continues today. The primary disadvantage of OPV is that, as an attenuated but active virus, it can very rarely induce vaccine-associated paralytic poliomyelitis (VAPP) in undervaccinated populations. On the other hand, IPV does not contain any live virus and cannot cause polio, but it may be less effective in preventing the spread of the disease between children.
Vaccines: Immune System Superpowers Explained
You may want to see also
Explore related products
OPV vs IPV
There are two types of polio vaccines: inactivated poliovirus vaccine (IPV) and oral poliovirus vaccine (OPV). IPV is administered as a series of shots and contains a killed, or inactivated, poliovirus. OPV, on the other hand, is given by mouth as a liquid and contains a weakened live vaccine.
IPV is the polio vaccine used in the United States, Canada, Europe, and many other countries where the risk of poliovirus infection is low. It is safe and proven to help prevent the spread of polio, protecting against poliovirus types 1, 2, and 3. IPV can cause mild side effects, such as a fever, pain, redness, or swelling at the injection site. However, it is important to note that IPV does not contain any live virus and cannot cause polio. Three doses of IPV provide at least 99% protection against severe disease caused by poliovirus.
OPV, on the other hand, is still used in some countries where the risk of poliovirus infection is high. It is low-cost and easy to administer to large numbers of people. OPV can create immunity in the vaccinated individual and can also spread to provide immunity to others nearby through saliva or faeces. However, rarely, the live virus in OPV can lead to paralysis in those it spreads to when the community is not sufficiently vaccinated. OPV was previously used in nationwide immunisation programmes in Cuba in 1962 and the Soviet Union in 1959, where it played a crucial role in interrupting the transmission of polio.
In April 2016, a global "OPV Switch" took place, setting the stage for the eventual withdrawal of all OPV. This switch involved replacing trivalent oral polio vaccines (tOPV) with bivalent oral polio vaccines (bOPV) in all OPV-using countries. As of July 2021, only two cases of wild poliovirus have been recorded globally that year, one each in Afghanistan and Pakistan.
To summarise, while OPV has played a significant role in polio eradication efforts, particularly in interrupting transmission, IPV is now the recommended vaccine in many countries due to its safety, effectiveness, and inability to cause polio. IPV is administered as a series of shots and provides excellent protection against poliovirus types 1, 2, and 3, with mild and typically short-lived side effects.
Kennedy's Lawsuit: Vaccine Companies' Verdict
You may want to see also
Explore related products
Vaccine-derived polio
The oral polio vaccine (OPV) has been crucial in eradicating wild polioviruses worldwide, including in the United States. OPV is a safe and effective vaccine that contains a weakened live poliovirus. It is administered orally, eliminating the need for sterile syringes, making it suitable for mass vaccination campaigns.
However, one of the primary disadvantages of OPV is its potential to induce vaccine-associated paralytic poliomyelitis (VAPP) in approximately one individual per 2.7 million doses administered. This occurs when the live virus circulates in under-vaccinated populations, termed circulating vaccine-derived poliovirus (cVDPV) or variant poliovirus. Over time, the weakened virus can revert to a virulent form, causing paralytic polio, although this typically does not affect the person who was originally vaccinated.
Circulating vaccine-derived polioviruses (cVDPVs) can emerge and lead to outbreaks of paralytic polio, particularly in communities with a high percentage of unvaccinated or under-vaccinated individuals. In 2023, the World Health Organization reported 74 cVDPV outbreaks in 39 countries, with 64% being new outbreaks. These outbreaks predominantly occurred in Africa, with 38 countries reporting cVDPV type 2 (cVDPV2) outbreaks.
To prevent the emergence of cVDPVs, it is crucial to achieve high vaccination coverage with the inactivated poliovirus vaccine (IPV). IPV is given as an injection and protects against paralytic disease caused by any type of poliovirus, including VDPV. Maintaining good hygiene practices, such as handwashing and access to clean water, as well as modern sewage systems, are also important measures to prevent the spread of poliovirus.
Smallpox Vaccines: Availability and Access in the USA
You may want to see also
Explore related products
Polio eradication
In 1988, the World Health Assembly passed a resolution to eradicate polio, leading to the Global Polio Eradication Initiative (GPEI). Since then, polio cases have decreased by over 99%, and vaccines have prevented an estimated 20 million cases of paralysis in children. However, polio remains endemic in Afghanistan and Pakistan, and other countries have experienced outbreaks of poliovirus variants due to low immunization rates.
The oral poliovirus vaccine (OPV) and the inactivated poliovirus vaccine (IPV) are the two types of vaccines used to prevent polio globally. OPV is the preferred vaccine in most countries due to its low cost, ease of administration, and ability to interrupt the transmission chain. However, OPV contains an attenuated but active virus, which can, in rare cases, cause vaccine-associated paralytic poliomyelitis (VAPP).
IPV, on the other hand, is given as an injection and does not contain any live virus, making it safer and more effective in preventing polio. It is the only polio vaccine used in the United States since 2000 and has proven safe and effective in protecting 99-100% of individuals who receive the recommended doses.
To achieve polio eradication, several key strategies have been outlined:
- High infant immunization coverage with four doses of OPV in the first year of life in developing and endemic countries, and routine immunization with OPV or IPV elsewhere.
- Organization of "national immunization days" to provide supplementary doses of OPV to all children under five years old.
- Active surveillance for poliovirus through reporting and laboratory testing of all cases of acute flaccid paralysis (AFP), a clinical manifestation of poliomyelitis.
The success of polio eradication efforts will ensure that children worldwide are protected from the devastating effects of the disease.
US Vaccines: Made in China?
You may want to see also
Frequently asked questions
No, the polio vaccine does not have bugs in it. The term "bugs" is often used to refer to errors or problems, and while there have been challenges and setbacks in the development and distribution of the polio vaccine, these are not inherent errors in the vaccine itself.
One notable issue was the Cutter Incident in 1955, where a defective polio vaccine caused 40,000 cases of polio and led to the abandonment of the first mass vaccination program. This incident, however, was due to issues in the manufacturing process and not a flaw in the vaccine's formulation.
The inactivated polio vaccine (IPV), which is the only type administered in the United States since 2000, has been proven safe and effective, protecting 99-100% of individuals who receive the full course. While some people may experience mild side effects like soreness at the injection site, IPV has not been known to cause serious problems.
OPV, which contains a weakened form of the poliovirus, is safe and effective but has a rare risk of causing vaccine-derived poliovirus (cVDPV) in under-vaccinated communities. This occurs when the weakened virus circulates and, over time, genetically reverts to a "strong" virus capable of causing paralysis.
As of July 2021, only two cases of wild poliovirus have been recorded globally that year: one in Afghanistan and one in Pakistan. While polio has been eliminated in most countries, continued efforts are needed to ensure complete eradication and prevent the resurgence of the disease.
