Poliomyelitis A80.9

• Poliovirus, genus Enterovirus, family Picornaviridae.
• Three serotypes: type I (Brunhilde), the most paralysing and epidemic spread; type II (Lansing) and type III (Leon). There is no cross-immunity between the three pathogen types.
• Mainly fecal-oral transmission. Shortly after the onset of infection massive virus reproduction occurs in the intestinal epithelia, so that infectious viruses can be excreted with the stool. Because of the primary virus reproduction in the pharyngeal epithelia, the virus can also be transmitted aerogenously shortly after infection. Poor hygienic conditions favour the spread of poliovirus infections. Sources of infection include contaminated water and food (mussels).
• Asymptomatic or sick people excrete the virus with stool and droplets (throat). Polioviruses can be detected in throat secretions at the earliest 36 hours after infection and persist there for about a week. Virus excretion in the stool begins after 72 hours and can last several weeks.

• Mainly occurring in developing countries in Africa and Asia with poor hygienic status. In the first years of life up to 90% of people in endemic areas become infected.
• Periodic outbreaks in endemic areas (e.g. 2006 in Namibia).
• Due to vaccination campaigns and improved hygienic conditions, the incidence of the disease is shifted into adulthood, sometimes with severe clinical progression.
• As a result of vaccination campaigns and the WHO poliomyelitis eradication programme, the entire American continent has been polio-free since 1994, the Western Pacific region since 2000 and Europe since 2002. The last case of poliomyelitis in Germany was registered in 1990.

• Abortive cases (5-10% of cases): incubation period: 6-9 days. Non-specific flu-like symptoms with fever, nausea, sore throat, lymphadenopathy, myalgias and headache. Furthermore symptoms of the upper respiratory tract (catarrh, non-purulent bronchitis) or gastroenteritis with diarrhoea.
• Non-paralytic poliomyelitis (1-2%): 3-7 days after abortive poliomyelitis, fever, neck stiffness, back pain and muscle spasms up to aseptic meningitis appear. Complete healing. Virus exanthema rarely occurs.
• Paralytic course or polioencephalitis (0.1-2%): After one or more days, meningism, asymmetrical flaccid paralysis or pareses appear within 24-48 hours. Partial and complete convalescence is possible. Fatal courses of bulbar paralysis are frequent.
• Sometimes the disease has a biphasic course. Initially, the symptoms of aseptic meningitis improve, but after 2-3 days there is an increase in fever and paralysis. This biphasic and rapid course of the disease is more common in children than in adults. The motor weakness usually occurs asymmetrically and can affect leg muscles (most commonly), arm, abdominal, thoracic or eye muscles. The bulbar form occurs less frequently and has a poor prognosis due to damage to cerebral or vegetative nerve centres.
• Post-polio syndrome: Sometimes occurring years or decades after infection as a late consequence. Symptoms: Extreme fatigue, muscle pain and muscle atrophy in new and previously affected muscles as well as breathing and swallowing difficulties.

• Virus cultivation from stool, from pharyngeal rinsing water and from cerebrospinal fluid.
• Molecular biological detection of RNA by PCR.
• Serum antibody detection by ELISA.

• Meningitis of other genesis, mainly caused by pathogens of the enterovirus group such as Coxsackie and Echoviruses and early summer meningoencephalitis.
• In bulbar form: diphtheria.
• Guillain-Barré syndrome, characterized by symmetrical paralysis rising from the feet in contrast to poliomyelitis.

• Hygiene, especially water treatment.
• Polio vaccination with inactivated polio vaccine (IPV; dead vaccine Salk against type I-III). This vaccine is safely effective and does not cause vaccine-associated paralytic poliomyelitis (VAPP). Even people with immunodeficiency can therefore be vaccinated with IPV without risk (inactivated vaccine Salk against type I-III). The oral live vaccine according to Sabin is no longer recommended due to the side effects (vaccination poliomyelitis).
• In individual cases the occurrence of acrodermatitis papulosa eruptiva infantilis after polio vaccination has been described.

Remember! According to § 6 IfSG, the public health department is notified by name of the suspected disease, the illness as well as death from poliomyelitis (suspicion is any acute flaccid paralysis of a limb, except when caused by trauma), and according to § 7 the direct or indirect detection of poliovirus, if it indicates an acute infection.

1. Reynolds T (2007) Polio: an end in sight? BMJ 27: 852-854
2. Thompson KM, Tebbens RJ (2007) Eradication versus control for poliomyelitis: an economic analysis. Lancet 21: 1363-1371