How it is transmitted and what happens
The virus is excreted in the feces of an infected person and reaches another through dirty hands, water, food, and objects. Less commonly, transmission occurs by airborne droplets in the first days of illness. Having multiplied in the intestines and lymphoid tissue of the pharynx, the virus stops there in most people. But sometimes it enters the bloodstream and reaches the anterior horns of the spinal cord, where the motor neurons are located. Their death leads to the fact that the muscle stops receiving the command and weakens. Sensitivity is preserved - the child feels the touch, but cannot move his leg.
- Fecal-oral transmission is the main route
- The virus is shed in the stool for several weeks
- Most cases are asymptomatic
- Motor neurons of the anterior horns of the spinal cord are affected
- Sensitivity is preserved, only movement is affected
Forms and symptoms
The inapparent form occurs without any manifestations and is detected only in the laboratory. Abortion resembles a common viral infection: fever, sore throat, nausea, loose stools, and ends with recovery in a few days. The meningeal form is accompanied by headache, vomiting and tension in the neck muscles, but does not cause paralysis. The paralytic form is the most severe: after a short improvement, the temperature rises again, muscle pain appears, and then weakness develops within one or two days, usually in one leg.
- Two-wave temperature with an interval of imaginary well-being
- Pain in the muscles of the back, neck and limbs
- Flaccid asymmetrical paralysis, usually of the legs
- Decreased or absent tendon reflexes
- Preserved sensation in the affected limb
- Swallowing and breathing disorders in the bulbar form
Consequences and rehabilitation
Restoration of muscle strength occurs within several months after the acute period, and what has not been restored within a year usually remains. Due to uneven muscle strength, deformities are formed: limb growth retardation, clubfoot, pelvic distortion, spinal curvature. Therefore, early involvement of rehabilitation, orthoses and orthopedic supervision is fundamentally important. Decades later, some survivors develop post-polio syndrome - increasing weakness and fatigue of previously restored muscles, requiring observation by a neurologist.
- Persistent weakness and atrophy of the muscles of the limb
- Growth retardation of the affected leg in children
- Contractures, clubfoot, foot deformities
- Scoliosis and pelvic distortion
- Respiratory disorders due to damage to the diaphragm
- Post-polio syndrome after years
Diagnostics
Each case of acute flaccid paralysis in a child under fifteen years of age is investigated according to a special protocol. For confirmation, two stool samples are taken at intervals to isolate the virus - this is the main method. Additionally, the cerebrospinal fluid is examined, where a moderate increase in cells and protein is detected. Electroneuromyography shows involvement of the anterior horns and helps distinguish poliomyelitis from other causes of weakness. MRI is used to rule out spinal cord compression and other diseases.
- Isolation of virus from two stool samples
- Cerebrospinal fluid examination
- Determination of antibodies in paired sera
- Electroneuromyography
- MRI of the spinal cord according to indications
- Examination by a neurologist with assessment of strength and reflexes over time
Prevention and vaccination
There is no specific treatment: neither antibiotics nor antiviral drugs act on the polio virus, therefore, in the acute period, maintenance therapy is carried out, limb rest and correct position are ensured, and in case of respiratory disorders, hardware support is provided. The only real protection is vaccination, which is included in the national calendar. The regimen includes an inactivated vaccine in injections and a live oral one; The specific dates are determined by the pediatrician according to the calendar. Refusal to vaccinate puts the child and others at risk again, because the virus is imported from disadvantaged countries.
- Vaccination according to the national vaccination calendar
- Compliance with revaccination deadlines, monitoring vaccination status
- Additional dose before traveling to a disadvantaged region on the advice of a doctor
- Hand washing, boiled water, washing vegetables and fruits
- Rest and correct position of the limb in the acute period
- Early rehabilitation, orthoses, observation by an orthopedist