On July 21, 2022, New York state health officials announced the first case of polio in the U.S. since 2013. The individual had not received a vaccine against polio.
Prior to the development of safe and effective vaccines in the mid-20th century, polio was a leading cause of paralysis in children. Due to global vaccination efforts, the disease is now close to being eradicated, with only 13 cases of wild poliovirus reported worldwide in 2022.
The New York patient contracted a form of polio linked to the weakened live poliovirus used in the oral vaccine, which has not been used in the U.S. since 2000. Health officials believe the virus was acquired overseas, where oral vaccines are still administered.
According to William Petri, an infectious disease expert, the inactivated polio vaccine used in the U.S. today cannot result in vaccine-derived poliovirus.
Vaccines play a crucial role in preventing infectious diseases and building immunity in individuals. By introducing a weakened or inactivated form of a pathogen into the body, vaccines stimulate the immune system to produce antibodies and memory cells that can recognize and fight off the actual virus or bacteria if exposed to it in the future.
In addition to the oral and injected polio vaccines mentioned, there are different types of vaccines available, including live attenuated vaccines, inactivated vaccines, subunit, recombinant, and conjugate vaccines. Each type works in a unique way to provide protection against specific diseases.
Vaccination not only helps protect the individual who receives the vaccine but also contributes to achieving herd immunity in the community. This means that when a large percentage of the population is vaccinated, the spread of infectious diseases is significantly reduced, benefiting those who are unable to receive vaccines due to medical reasons or age.
Understanding Vaccine-Derived Poliovirus
Although the weakened virus in the oral vaccine cannot cause disease, it can mutate and regain its ability to cause paralysis if it circulates among unvaccinated individuals for an extended period.
Instances of vaccine-derived polio are rare, with less than 800 cases reported globally out of over 10 billion doses of oral vaccine administered.
Efforts are underway to develop a safer oral polio vaccine that eliminates the risk of mutation, ensuring better protection against the disease.
Progress Towards Polio Eradication
With two of the three polioviruses eradicated, the world is close to eliminating the final strain, wild poliovirus 1.
Endemic polio remains in limited countries, emphasizing the importance of continued vaccination efforts to prevent future cases of vaccine-derived polio.
Once wild poliovirus is eradicated, the focus can shift to using the inactivated polio vaccine exclusively, reducing the risk of vaccine-derived poliovirus.
This article is republished from The Conversation. Read the original article.
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Left: A child receiving an oral polio vaccine in Yemen during a vaccination campaign. Khaled Abdullah/Reuters
The most effective way to protect against polio is by getting a polio vaccine, a standard part of childhood immunization schedules in the United States. While only IPV has been used in the U.S. since 2000, other countries still utilize OPV.
There are two types of polio vaccines available:
– IPV: Given by injection, it is the primary polio vaccine in the U.S. since 2000.
– OPV: No longer used in the U.S., but still found in various parts of the world.
Children in the U.S. should receive IPV to prevent polio, while adults may also need this vaccine based on their vaccination history or potential exposure risks. Those traveling to high-risk polio regions should also get vaccinated, and at-risk adults should consider booster shots.
IPV offers robust protection against polio, preventing lifelong paralysis and potential fatalities associated with the disease. It is crucial to keep all individuals, especially children, up to date with polio vaccinations to prevent the spread of the virus.
Various resources, such as health insurance and vaccination programs, can help cover vaccine costs. State laws mandate immunization requirements for children in schools and childcare facilities.
Good hand hygiene and regular vaccination are key preventive measures against polio. Regular check-ups ensure individuals are adequately protected. If planning to travel overseas, consult with a healthcare professional beforehand.
Polio, a highly contagious virus, is primarily spread through feces, though it can also be transmitted through coughs or sneezes. Although the risk of polio in the UK is low due to vaccination, traveling to countries like Afghanistan or Pakistan where polio is still present carries a slight risk.
While most polio cases are asymptomatic, some individuals may experience mild flu-like symptoms such as high temperature, extreme fatigue, headaches, vomiting, stiff neck, and muscle pain. In severe cases, polio can cause muscle weakness or paralysis.
If experiencing symptoms like inability to move parts of the body or difficulty breathing, seek immediate medical attention. Do not attempt to drive yourself, call for an ambulance or have someone take you to the hospital.
If you develop flu-like symptoms and are concerned about a child’s symptoms, elderly, pregnant, have a chronic medical condition, weakened immune system, or symptoms persist beyond 7 days, seek medical advice.
While there is no cure for polio, certain types of care can help reduce the risk of long-term issues such as bed rest in a hospital setting, pain relief medication, assistance with breathing, and regular stretching and exercises. Some individuals may require specialized care like physiotherapy or surgery if long-term problems arise.
Polio can lead to lifelong challenges, including paralysis and ongoing medical needs like muscle weakness, joint issues, and swallowing difficulties. Individuals who have had polio previously may experience a recurrence of symptoms known as post-polio syndrome.