Polio vaccines vaccine-associated

Billions of doses of vaccines were safely administered over the last century to millions of infants, children, and adults [1,4], Vaccine-associated adverse events were nevertheless identified in a minority of patients. Many of the adverse events were directly related to the vaccine others as in the case of MMR have not been substantiated with data but still cause considerable public unease [1], One documented case is that of vaccination with a formalin-inactivated respiratory syncytial virus (RSV) that, when given prophylactically, caused enhanced disease after exposure to the virus and resulted in the death of some children [1,4,5], An increased incidence of Guillain-Barre syndrome appeared to be associated with a swine flu vaccine that was tested in humans in the late 1970s [1,6]. Guillain-Barre syndrome has also been associated with other vaccines including those for polio, measles, and hepatitis B [6]. 

In contrast to IPV, OPV causes important problems, including vaccine-associated polio and prolonged polio virus excretion. 

Acute disseminated encephalomyelitis associated with polio vaccine has been reported (32). 

The available reports on a possible association between polio vaccine and Guillain-Barre syndrome have been reviewed (34). The conclusion of a 1994 US Institnte of... 

VI. Vaccines containing live oral poliovirus (OPV) A. Paralytic polio in a non-immunodeficient recipient in an immunodeficient recipient in a vaccine associated community case B. Vaccine-strain polio viral infection in a non-immunodeficient recipient in an immunodeficient recipient in a vaccine associated community case C. Any acute complication or sequela (including death) of the above events 0-30 days 0-6 months Not applicable 0-30 days 0-6 months Not applicable Not applicable... 

An analogous example in the civilian context could be made in the case of polio immunizations, where a 1 in 2.4 million chance exists that an oral polio virus vaccine will actually cause the disease. The risk posed by the vaccine is extremely small, but it is real, and yet poliomyelitis hasn t been seen in the Western Hemisphere since 1991. On an individual basis, a case could be made that the chances of acquiring polio, unless one travels abroad or has contact with people from endemic regions, is even less than that of acquiring vaccine-associated paralytic poliomyelitis. But there is no question that continued polio vaccinations are required in the United States, and indeed a global eradication campaign is underway to completely eliminate the virus. 

Acute paralytic poliomyelitis is still endemic in some countries and vaccine-associated poliomyelitis continues to occur (125). After many years of stability, some patients do deteriorate (126). This post-polio syndrome may be characterized by the development of progressive weakness associated with respiratory symptoms among those ventilated during their acute illness (127). Respiratory failure results from thoracic restriction as well as muscle weakness and bulbar involvement (128). Tracheostomy can be avoided with continuous NIV and aggressive mechanical in-exsufflation (128). Retrospective studies of NIV have reported survival rates >90% at five years, making this group the one with the highest benefit (76,129). 

Poliomyelitis is a highly contagious disease that is often asymptomatic however, approximately 1 in every 100 to 1000 cases will develop a rapidly progressive paralytic disease. Polio is caused by poliovirus which has three serotypes type 1 is most frequently associated with paralytic disease. Poliovirus replicates in the oropharynx and intestinal tract and is excreted in oral secretions and feces, which can infect others. As a result, more than 90% of unvaccinated individuals will become infected with poliovirus following household exposure to wild-type poliovirus. Since the introduction of the first poliovirus vaccine, there has been a significant reduction in the number of polio cases. Today, polio caused by wild-type poliovirus has been eradicated from the Western Hemisphere with the goal of eradicating it from the world.11... 

The third policy, the Vaccine Injury Compensation Fund, introduced a government-run, no-fault product liability system that reduced the mean and variance of product liability costs associated with four childhood vaccines polio, diphtheria-tetanus, measles-mumps-rubella, and pertussis. 

In the 15 years since these criteria were promulgated by declaration, it will be evident that most vaccines are still administered parenterally with the exception of polio and typhoid vaccines. In many ways this can be attributed to the physicochemical characteristics of vaccine antigens themselves, which are large molecules susceptible to proteolytic degradation, denaturation, and rapid clearance from plasma. Some combination vaccines are available which reduce the number of injections. However, the MMR (measles, mumps, and rubella) combination vaccine has gained an unsafe image in the popular press, mainly due to a reputed link with autism in some children that as yet remains unproven scientifically. In some quarters the autism was associated with the use of thiomersalate as a mercurial preservative in multidose injections but, again, this supposition remains unproven. 

Guillain-Barrb syndrome was particularly associated with swine flu vaccine in 1976. It has rarely been associated with other vaccines — tetanus toxoid, BCG, rabies, smallpox, mumps, rubella, hepatitis B, diphtheria, and polio (Wraith et al., 2003). 

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