Friday, September 16, 2022 (Kaiser News) — Before polioWhen vaccines were first made available in 1950s, many people who were worried about this crippling disease couldn’t allow their children to go outside or even to school. As polio appears again decades after it was considered eliminated in the U.S., Americans unfamiliar with the dreaded disease need a primer on protecting themselves and their young children — many of whom are emerging from the trauma of the covid-19 pandemic.
What is Poliomyelitis?
Polio is short for “poliomyelitis,” a neurological disease caused by a poliovirus infection. Of the three types of wild poliovirus — serotypes 1, 2, and 3 — serotype 1 is the most virulent and the most likely to cause Paralysis.
Most people infected with poliovirus don’t get sick and won’t have symptoms. Mild symptoms, such as fatigue, fever, headaches, stiffness of the neck, nausea, vomiting and sore throat, may be experienced by about 25% of those infected. Angina. So, as with covid-19, people who don’t have symptoms can unknowingly spread it as they interact with others. However, the virus could infect the brain or spinal cord of up to one in 200 people with poliovirus. People may experience paralysis or muscle weakness if the virus infects their spinal cord. Infections of the brain can also cause difficulties breathing or swallowing.
People can develop post-polio syndrome decades after infection. Muscle pain, weakness, or wasting are some of the symptoms.
Persons with poliomyelitis might remain paralysed or unable breathe for the rest of the life.
How does polio spread?
The virus that causes polio spreads through the “oral-fecal route,” which means it enters the body through the mouth by way of the hands, water, food, or other items contaminated with poliovirus-containing feces. Rarely, poliovirus can spread through saliva or upper respiratory droplets. The virus infects the throat, gastrointestinal tract, and then spreads to blood and into the nervous system.
How do doctors diagnose polio?
A combination of patient interviews and physical examinations, laboratory testing, and scans to the spine or brain can diagnose poliomyelitis. To perform lab testing, health care providers may request specimens such as feces and throat swabs. Because polio is a rare disease in the United States, doctors might not diagnose patients with symptoms. Because the tests for suspected polio are no longer performed at academic centers, it is important that you send them to the Centers for Disease Control and Prevention.
How can we stop poliovirus transmission?
The CDC recommends that children aged 2 to 6 years old be vaccinated against polio in four doses. The District of Columbia and all 50 states require that children in day care or public schools be immunized against Polio. However, some states allow exemptions for medical, religious or personal reasons. Children who are eligible for Medicaid, are uninsured or underinsured or are American Indians or Alaska Natives are eligible for polio vaccine at no cost through the Vaccines for Children program. The majority of Americans born after 1955 have likely been vaccinated against polio. But in some areas the vaccination rates are dangerously low, such as New York’s Rockland County, where it is 60%, and Yates County, where it is 54%, because so many families there claim religious exemptions.
There are two types polio vaccines available: the dead, inactivated polio virus (IPV), and the weaker, live oral poliovirus (OPV). IPV is an injectable vaccine. OPV may be given by drops in the mouth or on a sugar cube, so it’s easier to administer. Both vaccines have high effectiveness against paralytic poliomyelitis. However OPV seems to be more effective in preventing infection or transmission.
Infection can be caused by both the wild poliovirus virus and the weakened OPV viruses. It is not possible for IPV to infect, replicate, give birth to vaccine-derived Poliovirus or cause paralytic Poliomyelitis. The weakened, OPV viruses can mutate and regain their ability to cause paralysis — what’s called vaccine-derived poliomyelitis.
Only IPV has ever been administered in the United States since 2000. IPV is effective in at least 90% of cases, and at least 99% of paralytic poliomyelitis cases when used in three doses. The United States discontinued OPV use due to a 1-in-2 risk of paralysis among OPV-vaccinated individuals. Some countries still use OPV.
The United States began polio vaccination in 1955. The number of cases of paralytic Poliomyelitis disease has dropped dramatically from 15,000 to 100 per year in the 1950s, to less than 100 by the 1960s, and down to 10 to 10 in the 1970s. Poliovirus today is more likely to spread in areas where sanitation and hygiene are poor and vaccination rates low.
Why is polio returning to the streets?
According to the World Health Organization, North and South America were declared polio-free in 1994. However, in June 2022, a young man from Rockland County in New York was diagnosed with serotype 2 vaccine derived poliovirus. The patient complained about fever, stiffness in the neck, and weakness in his legs. The patient was not known to have traveled outside the United States in recent months and was therefore likely infected here. The CDC began to monitor the water supply for poliovirus. The Rockland County case of poliovirus has been genetically linked to wastewater samples from Orange, Sullivan, and Rockland counties. This shows that the virus spreads back as far as May 2022. New York City wastewater also contained poliovirus unrelated to that which was derived from vaccines.
How do I know if I’ve been vaccinated against polio?
Although there is not a national database of immunization records available, all 50 states and District of Columbia have immunization information networks that can store records dating back to the 1990s. You may have records from your vaccinations kept by your state or territory health department. Arizona, Washington, Louisiana and Mississippi are the only states that have immunization records. Those who have been immunized in Washington, Louisiana and Maryland can access them using the MyIR mobile app. Those who received vaccines in Idaho and Minnesota can use the Docket app.
Ask your parents, childhood physician, current pharmacist, K-12 schools or universities if they have any records of your vaccinations. Some employers, like the health care system, may keep records of your vaccinations at their occupational health office.
There is no test to determine if you’re immune to polio.
If I have been fully vaccinated against the disease as a child, do I still need to get a booster vaccine?
All children should have the recommended four-dose series polio vaccinations. If you have received an OPV, you don’t need an IPV booster.
An IPV booster is available for adults with immunocompromised who travel to countries where poliovirus can be found.
How is polio managed?
People with mild poliovirus infection don’t require treatment. Symptoms typically disappear on their own in a matter of days.
Paralytic poliomyelitis cannot be cured. The treatment focuses on occupational and physical therapy to aid patients in adapting and regaining function.
Why hasn’t poliovirus been eradicated?
The only known human virus that has been declared eliminated is smallpox. A disease can be considered eradicated if it only infects humans and there is a preventive or vaccine that works. The more severe a disease is, the harder it will be to eradicate. It is also more difficult for viruses to spread unsymptomatically.
The 1988 World Health Assembly resolution to eliminate polio by 2000 was passed. Although violence, conspiracy theories, vaccine doubticism, inadequate funding, political will, and poor quality vaccination efforts have slowed progress towards eradication, it was still very close before the covid epidemic. Children’s immunizations including polio vaccinations dropped in the U.S. as well as around the globe during the pandemic.
All vaccine-derived polioviruses as well as wild polioviruses must be eradicated in order to eradicate polio. The wild poliovirus serotypes 2, and 3, have been eliminated. Although wild poliovirus serotype 1 is the most dangerous, it remains endemic in Pakistan, Afghanistan, and some other countries in Africa, vaccine-derived polioviruses still circulate in some parts of the world. It would likely take a gradual approach that involves OPV, IPV, then a combination, and finally IPV alone to eradicate polio worldwide.
KHN (Kaiser Health News), a national newsroom, produces in-depth journalism on health issues. KHN (Kaiser Family Foundation) is part of three important operating programs. It includes Policy Analysis and Polling. KFF is an endowed non-profit organization that provides information to the nation on health issues.
