Polio, or poliomyelitis, is a crippling and potentially deadly infectious disease. It is caused by the polio virus. The virus spreads from person to person and can invade an infected person’s brain and spinal cord, causing paralysis (can’t move parts of body). SYMPTOMS Most people who get infected with polio virus (about 72 out of 100) will not have any visible symptoms. About 1 out of 4 people with polio virus infection will have flu-like symptoms that may include sore throat, Fever, Tiredness, Nausea, Headache, and Stomach pain. These symptoms usually last 2 to 5 days then go away on their own. A smaller proportion of people with polio virus with polio virus infection will develop other more serious symptom that affect the brain and spinal cord: Paresthesia (feeling of pins and needles in the legs), Meningitis (infection of the covering of the spinal cord and/or brain) occurs in about 1 out of 25 people with polio virus infection, Paralysis (can’t move parts of the body) or weakness in the arms, legs, or both, occurs in about 1 out of 200 people with polio virus infection Paralysis is the most severe symptom associated with polio because it can lead to permanent disability and death. Between 2 and 10 out of 100 people who have paralysis from polio virus infection die because the virus affects the muscles that help them breathe. Even children who seem to fully recover can develop new muscle pain, weakness, or paralysis as adults, 15 to 40 years later. This is called post-polio syndrome. Note that “poliomyelitis” (or “polio” for short) is defined as the paralytic disease. So only people with the paralytic infection are considered to have the disease. TRANSMISSION Polio virus only infects humans. It is very contagious and spreads through person-to-person contact. The virus lives in an infected person’s throat and intestines. It enters the body through the mouth and spreads through contact with the feces (poop) of an infected person and, though less common, through droplets from a sneeze or cough. You can get infected with polio virus if you have feces on your hands and you touch your mouth. Also, you can get infected if you put in your mouth objects like toys that are contaminated with feces (poop). An infected person may spread the virus to other immediately before and about 1 to 2 weeks after symptoms appear. The virus can live in an infected person’s feces for many weeks. It can contaminate food and water in unsanitary conditions. People who don’t have symptoms can still pass the virus to others and make them sick. Prevention Polio vaccine protects children by preparing their bodies to fight the polio virus. Almost all children (99 children out of 100) who get all the recommended doses of vaccine will be protected from polio. There are two types of vaccine that can prevent polio: inactivated polio virus vaccine (IPV) and oral polio virus vaccine (OPV). Only IPV has been used in the United States since 2000; OPV is still used throughout much of the world. HISTORY OF POLIO In the early 20th century, polio was one of the most feared diseases in industrialized countries, paralyzing hundreds of thousands of children every year. Soon after the introduction of effective vaccines in the 1950s and 1960s, however, polio was brought under control and practically eliminated as a public health emergency in these countries. It took somewhat longer for polio to be recognized as a major problem in developing countries. Lameness surveys during the 1970s revealed that the disease was also prevalent in developing countries. As a result, during the 1970s, routine immunization was introduced worldwide as part of nation immunization programmes, helping to control the disease in many developing countries. In 1988, when the Global Polio Eradication Initiative began, polio paralyzed more than 1000 children worldwide every day. Since then, global incidence of polio has declined by 99%, and more than 2.5 billion children have been immunized against polio thank to the cooperation of more than 200 countries and 20 million volunteers, backed by an international investment of more than US$ 11 billion. There are now only 3 countries that have never stopped polio transmission: Pakistan, Afghanistan and Nigeria. There has also been success in eradicating certain strains of the WPV1 virus. For example, the cause of type 2 was reported in 1999 and its eradication was declared in September 2015. Meanwhile, the most recent cause of type 3 dates to November 2012. However, tracking the last 1% of polio cases has still proved to be difficult. Conflict, political instability, hard-to-reach populations, and poor infrastructure continue to pose challenges to eradicating the disease. Each country offers a unique set of challenges which require local solutions. In 2013, The Global Polio Eradication Initiative launched its most comprehensive and ambitious plan A smaller proportion of people with polio virus with polio virus infection will develop other more serious symptom that affect the brain and spinal cord: Parenthesis (feeling of pins and needles in the legs), Meningitis (infection of the covering of the spinal cord and/or brain) occurs in about 1 out of 25 people with polio virus infection, Paralysis (can’t move parts of the body) or weakness in the arms, legs, or both, occurs in about 1 out of 200 people with polio virus infection Paralysis is the most severe symptom associated with polio because it can lead to permanent disability and death. Between 2 and 10 out of 100 people who have paralysis from polio virus infection die because the virus affects the muscles that help them breathe. A smaller proportion of people with polio virus with polio virus infection will develop other more serious symptom that affect the brain and spinal cord: Parenthesis (feeling of pins and needles in the legs), Meningitis (infection of the covering of the spinal cord and/or brain) occurs in about 1 out of 25 people with polio virus infection, Paralysis (can’t move parts of the body) or weakness in the arms, legs, or both, occurs in about 1 out of 200 people with polio virus infection Paralysis is the most severe symptom associated with polio because it can lead to permanent disability and death. Between 2 and 10 out of 100 people who have paralysis from polio virus infection die because the virus affects the muscles that help them breathe. A smaller proportion of people with polio virus with polio virus infection will develop other more serious symptom that affect the brain and spinal cord: Parenthesis (feeling of pins and needles in the legs), Meningitis (infection of the covering of the spinal cord and/or brain) occurs in about 1 out of 25 people with polio virus infection, Paralysis (can’t move parts of the body) or weakness in the arms, legs, or both, occurs in about 1 out of 200 people with polio virus infection Paralysis is the most severe symptom associated with polio because it can lead to permanent disability and death. Between 2 and 10 out of 100 people who have paralysis from polio virus infection die because the virus affects the muscles that help them breathe. A smaller proportion of people with polio virus with polio virus infection will develop other more serious symptom that affect the brain and spinal cord: Parenthesis (feeling of pins and needles in the legs), Meningitis (infection of the covering of the spinal cord and/or brain) occurs in about 1 out of 25 people with polio virus infection, Paralysis (can’t move parts of the body) or weakness in the arms, legs, or both, occurs in about 1 out of 200 people with polio virus infection Paralysis is the most severe symptom associated with polio because it can lead to permanent disability and death. Between 2 and 10 out of 100 people who have paralysis from polio virus infection die because the virus affects the muscles that help them breathe.