The virus spreads via person-to-person transmission, primarily through the fecal-oral route, and occasionally through contaminated water or food, where it then proliferates within the gastrointestinal system.
The array of clinical presentations varies, encompassing mild occurrences of respiratory troubles, gastrointestinal disturbances, and general unease, to more severe cases resulting in paralysis. These expressions of the disease are classified as asymptomatic infections, mild instances (known as abortive poliomyelitis), non-paralytic meningitis (referred to as aseptic meningitis), and paralytic poliomyelitis.
Approximately a quarter of individuals infected with the poliovirus undergo flu-like symptoms, such as a sore throat, fever, fatigue, nausea, headache, and stomach discomfort. These symptoms persist for approximately 2 to 5 days before resolving on their own.
A smaller subset of those afflicted by the poliovirus exhibit more grave symptoms impacting the brain and spinal cord:Meningitis, occurring in approximately 1–5% of cases depending on the virus type, involves infection of the protective coverings of the spinal cord and/or brain.
Paralysis or weakness in the arms, legs, or both is discerned in about 0.5% to 0.05% of cases, contingent on the virus type.
The poliovirus is categorized into three strains: wild poliovirus type 1, 2, and 3 (WPV1, WPV2, and WPV3). While types 2 and 3 have been eradicated, type 1 persists in a few isolated regions. Type 1 carries the highest likelihood of causing paralysis.
Global campaigns for vaccination have significantly curtailed the global incidence of cases in recent years. Nevertheless, instances of polio still emerge in regions with insufficient vaccination coverage.
The U.S. Centers for Disease Control and Prevention (CDC) furnishes travel advisories for countries with heightened polio risk. Typically, these countries are situated in Africa, the Middle East, and certain parts of Asia.
Polio: Causes, Symptoms, Vaccination
