Michael Underwood first described the Polio disease in 1789. The highly contagious disease is also known as Poliomyelitis. Polio disease results from a virus known to attack a person’s nervous system and has been a problem globally, with the disease remaining endemic in Nigeria, Afghanistan, and Pakistan (Lima et al., 2021). Poliovirus is grouped under the enterovirus subgroup under the family Picornaviridae (“CDC,” 2021). The Picornaviruses are described as small viruses insensitive to ether and contain an RNA genome (CDC, 2021). Currently, there exist three types of wild Poliovirus. They include type 1, type 2, and type 3, abbreviated as WPV1, WPV2, and WPV3, respectively (“UNICEF,” 2021). Studies indicate that one in 200 people affected by the Poliovirus has irreversible paralysis, with 5% to 10% of the patients dying due to respiratory muscle paralysis (“WHO,” 2019).
Evidence of the existence of the disease can be traced back to as far as in Egyptian mummies (Sabbatani and Fiorino, 2008). The disease had been a significant problem until the 1950s, when the Sabin and Salk vaccines were developed (Lima et al., 2021). A report by the Unicef Executive Board indicates that between the years 2020 and 2021, there were 101 and 75 confirmed polio paralysis cases globally (“UNICEF,” 2021). The World Health Organization (2019) states that polio cases had decreased from 350,000 in 1988 to 33 cases in 2018. Among these numbers, the number of Wild Polio Virus (WPV) reported in Afghanistan and Pakistan were 5 and 41 in 2020 and 1 in both countries from the beginning of January to 5th May in both years (UNICEF,” 2021). The report further indicates that there have been significant efforts to reduce these numbers, with a reported 99.9 percent decrease between 1988 and 2021 (“UNICEF,” 2021). The pathogenesis of the disease is from the mouth and propagates in the oropharynx and gastrointestinal tract (“CDC,” 2021). The Poliovirus stays in the nasopharyngeal secretions for one to two weeks, where it can be discharged in stool for many weeks after the infection has occurred. In the intestines, the Poliovirus attacks the local lymphoid cells, and at times, it may invade the bloodstream and further cause infection to the central nervous system cells (“CDC,” 2021). The disease can cause further damage to the motor neurons at the anterior part of the spinal cord and further affect the brain stem cells, resulting in paralysis. The disease primarily affects children under the age of 5 years (“WHO,” 2019). However, research indicates that the risk of the disease increases as the age of individual increases.
Diagnosis of Polio
The period of incubation for nonparalytic polio commences from 3 to 6 days, while for paralytic poliomyelitis, the incubation period begins at 7 to 21 days (“CDC,” 2021). Studies also indicate that around 70% of Poliomyelitis is asymptomatic. The disease is usually diagnosed through checking of stool and throats since most of the viruses stay in the stool before being transmitted with the method being called. The diagnosis is carried mainly through laboratory testing of the stool or cerebrospinal fluid (“CDC,” 2021). The method of diagnosing through checking the stool sample, or through the throat, and from the cerebrospinal fluid is called viral culture. During the testing, stool samples should be collected at least 24 hours apart and after 14 days when the symptoms start since viral shedding may be irregular since the viral load decreases after the start of paralysis. The disease can also be diagnosed by monitoring its symptoms, including stiffness of the neck, vomiting, headache, fever, tiredness, and limb pain (WHO, 2019). Other methods of diagnosing Poliomyelitis include reverse transcriptase, which involves blood and cerebrospinal fluid (Tesini, 2021). If there are no symptoms in the central nervous system, serological testing can be applied (Tesini, 2021).
In nonparalytic Poliomyelitis, lumbar puncture is usually done for diagnostic purposes. Normal findings that indicate the presence of the virus in the cerebrospinal fluid include normal glucose levels, slightly high protein level, and a 10 to 500/mcL cell count, which is majorly lymphocytes (Tesini, 2021). The presence of the virus in the feces, though a throat swap, in the cerebrospinal fluid, or through an increase in a particular antibody proves that the virus infects the patient. In paralytic poliomyelitis, the virus may be present in children who are not immunized or adolescents with asymmetric flaccid limb paralysis (Tesini, 2021). However, other echovirus and enterovirus 71 may reveal indistinguishable results. Additionally, other epidemiological factors such as the immunization past, age, and travel history of the individual may help understand the cause of the virus.
In the case of nonparalytic Poliomyelitis, there is a total recovery in patients suffering from the infection. The recovery period takes less than one week. In paralytic poliomyelitis, around two-thirds of the patients develop extra permanent weakness (Tesini, 2021). CDC (2021) outlines that less than 1% of children infected with polio lead to flaccid paralysis with the effect being biphasic in minors who may have suffered from minor illnesses that occur for several days that is characterized by lack of symptoms for up to 3 days and a further paralysis and muscle pain. There is no minor illness in adults, and the patients directly incur severe pain and paralysis (“CDC,” 2021). Paralysis resulting from Poliomyelitis is majorly permanent, with some minor cases of total and incomplete recovery occurring by the replacement of muscles that have not been affected (“CDC,” 2021). Paralysis as a result of Poliomyelitis is categorized into three types concerning the degree of complicity.
Spinal polio is the most incident and is attributed to irregular paralysis, which mostly occurs on the legs, followed by Bulbar polio, which is characterized by muscle weakness in the face and respiratory regions (“CDC,” 2021). The third type of paralytic polio is Bulbospinal polio which comprises both bulbar and spinal paralysis. The fatality rate associated with paralytic polio is 2% to 5% in minors, with the number rising to 15% to 30% in young adults and a further 25% to 75% with individuals suffering from bulbar polio (“CDC,” 2021). Other evidence indicates that after 15 to 40 years, 25 percent to 40 percent of individuals who had suffered from paralytic polio during their childhood start experiencing renewed pains in the muscles and aggravated underlying weakness and in some cases may suffer from new weaknesses and paralysis (“CDC,” 2021). This condition is referred to as post-polio syndrome.
There is no known cure for polio. However, some interventions have been recognized to be significantly contributing to the eradication of the disease. These interventions are offered through supportive care, which involves analgesics, rest for patients, and antipyretics (Tesini, 2021). The disease can be further alleviated through preventive measures, including immunization through the poliomyelitis vaccine. The immunization schedule against polio occurs four times after an individual has taken four doses of the vaccine. The first schedule occurs at two months after birth, followed by four months, the third vaccine at six to 18 months after birth, with the last dose at four to six years after birth and is known as the booster dose (Tesini, 2021). There are two types of polio vaccines used to prevent it. They include the Salk vaccine as well as the Sabin vaccine (Lima et al., 2021). Salk, IPV is injectable, and it comprises inactivated viruses with Sabin, Sabin, OPV, on the other hand, is administered orally and is made up of attenuated viruses (Lima et al., 2021). Applying these two types of vaccines among different populations has resulted in reduced polio cases globally, with reports indicating a 99.9% reduction of the Poliovirus between 1988 and 2021 (“UNICEF,” 2021). The vaccines have contributed to the alleviation of two types of wild Poliovirus since the start of their application.
Many regions have been marked polio-free by the World Health Organization, with Africa being the latest to be considered wild polio-free in 2020 (“UNICEF,” 2021). The alleviation process is divided into three distinct stages. The first stage began after the World Health Assembly made decisions and set 2000 as the date for eradicating the virus. However, this target was not achieved, but there was a significant reduction in the number of endemic countries, decreasing from 125 in 1988 to 20 in 2000 (Lima et al., 2021). During the first phase, the United States has declared a polio-free nation (Lima et al., 2021). The second stage of eradication commenced in 2001 and lasted until 2010, with the last phase emphasizing marginalized areas, with countries such as India being declared polio-free. These measures have, therefore, considerably contributed to the alleviation of polio.
Center for Disease Control and Prevention, CDC. (2021). Poliomyelitis. https://www.cdc.gov/vaccines/pubs/pinkbook/downloads/polio.pdf
Lima, E. S., Romero, E. C., & Granato, C. F. H. (2021). Current Polio Status in the World. Jornal Brasileiro de Patologia e Medicina Laboratorial, 57.
Sabbatani, S., & Fiorino, S. (2008). Contribution of Paleopathology to Defining the Pathocoenosis of Infectious Diseases (Part one). Le Infezioni in Medicina, 16(4), 236-250.
Tesini, L.B. (2021). Poliomyelitis (Infantile Paralysis; Acute Anterior Poliomyelitis; Polio). https://www.msdmanuals.com/professional/infectious-diseases/enteroviruses/poliomyelitis
UNICEF. (2021). Polio Global Overview- Status of Polio Eradication. https://www.unicef.org/executiveboard/media/5501/file/2021_AS-SFS-Polio_Global_Overview-Information_note-EN-2021.05.20.pdf
World Health Organization. (2019). Poliomyelitis. http://www.who.int/news-room/fact-sheets/detail/poliomyelitis