Spinal cord anterior horn cell lesions are caused by these causes

Anterior horn cell lesions of the spinal cord are a manifestation of osteomyelitis and are also an acute disease caused by osteomyelitis virus. Studies have found that all antibiotics or chemotherapy drugs currently in use are not effective against myeloma virus, and the only relief is the use of myeloma virus vaccine.

1. Resistance: Poliovirus is insensitive to all known antibiotics and chemotherapeutic drugs, and can withstand chemical disinfectants of normal concentrations, such as 70% ethanol and 5% coal tar soap solution. 0.3% formaldehyde, 0.1mmol/L hydrochloric acid and (0.3～0.5)10-6 residual chlorine can quickly inactivate it, but it can be protected in the presence of organic matter. Heating to 56°C for 30 minutes can completely inactivate it, but it can be stored for several years in a frozen environment, for several weeks in a 4°C refrigerator, and for several days at room temperature. Sensitive to UV rays, dryness and heat. Can survive for months in water, feces and milk. Magnesium chloride can enhance the virus's resistance to temperature, so it is widely used to preserve live attenuated vaccines.

2. Antigenic properties can be divided into three serotypes: I, II, and III using serum neutralization test. Each serotype of virus has two type-specific antigens. One is the D (dense) antigen, which exists in mature virions. Viruses containing the D antigen are fully infectious and antigenic. The other is the C (coreless) antigen, which exists in the procapsid of the virus. Viruses containing the C antigen are empty shell particles lacking RNA and are not infectious. Under the action of neutralizing antibodies, the virus's D antigenicity can be transformed into C antigenicity, and it loses the ability to infect cells again. The heat-inactivated virus loses VP4 and RNA and becomes virus particles containing C antigen. The natural D antigen and the heated C antigen can be detected by precipitation reaction and complement fixation test.

3. Host range and virulence Humans are the natural hosts and reservoir hosts of poliovirus, and monkeys and gorillas are susceptible animals. The virus binds to specific receptors on the cell surface and is taken into the cell, replicating in the cytoplasm while releasing inhibitors to inhibit the synthesis of host cell RNA and protein.

Natural polio viruses are called wild strains, and virus strains that have been attenuated in the laboratory are called vaccine strains. The vaccine strain caused paralysis only when injected directly into the central nervous system of monkeys and was non-toxic to human nerve cells. Vaccine strain viruses, especially type III viruses, can mutate into toxic intermediate strains when spreading among the population. The most reliable method for distinguishing field and vaccine strains is nucleic acid sequence analysis.