Sunday, November 16, 2014

Oral Polio Vaccine : Safe?

Polio vaccine: Is it really as safe as it is claimed to be?

Published: November 10, 2014
Is the Oral Polio Vaccine (OPV), which is administered to millions of children in the developing world, really safe? PHOTO: AFP
Reporting on polio vaccination has secured a regular slot in major media outlets. The reporting is mostly always supportive of the vaccination campaign commonly called “polio eradication”. But is the Oral Polio Vaccine( OPV), or Sabin vaccine (named after Albert Sabin), which is administered to millions of children in the developing world, really safe? Does it have no harmful effect on human health a claimed by some doctor in a recent story?
The short answer is: no, it’s not completely safe. Not only can it cause permanent disability in some children, it actually has caused epidemics of paralysis in at least two countries – Nigeria and India. It’s been officially admitted and reported in media many a time, though the media in Pakistan tends not to talk about it or its history beyond the version endorsed by the authorities.
The most well-known (or infamous, for that matter) epidemic of the paralysis caused by the OPV happened in Nigeria in the period ranging July 2005 to June 2010. An outbreak of vaccine-derived poliovirus (VDPV) caused 315 reported cases of type 2 circulating vaccine-derived poliovirus (cVDPV2). The incident followed the use of OPV to immunise children in Nigeria where polio caused by wild poliovirus has remained endemic.
The Nigeria outbreak caused by the vaccine led Steven Wassilak of the Centers for Disease Control and Prevention (CDC) to write a research paper on such cases. His paper titled ‘Outbreak of Type 2 Vaccine-Derived Poliovirus in Nigeria: Emergence and Widespread Circulation in an Under-immunised Population’ was published in The Journal of Infectious Diseases (2011)’. The paper noted that vaccine-caused paralytic polio is clinically indistinguishable from that caused by the wild polioviruses.
In India, which was been declared free of polio in 2013, a notable rise in cases of vaccine-induced paralysis has been reported over the past three years. Acute Flaccid Paralysis (AFP) is one of the types of permanent paralysis, and is considered as a sign of acute or debilitating polio. The incidence of AFP reportedly soared in India over the period of 1996 to 2011 with 60,000 new cases reported in 2011. Various sources have placed the number of vaccine-associated AFP cases in India variedly, but hardly anyone reported less than 45,000 cases in 2012.
The risk of paralysis and serious harm associated with OPV was indeed the reason that led most of Europe, particularity Western Europe, as well as the United States to “discontinue” the use of OPV for immunisation. The word “discontinue” is of course a euphemism for “banned” so as to linguistically benefit the OPV which is the foundation of international health projects worth hundreds of millions of dollars a year. As reported in a 2004 paper published in the Journal of American Medical Association (JAMA), all cases of polio reported in the US since 1979 were cases of Vaccine-Associated Paralytic Poliomyelitis (VAPP). That is why the vaccination policy was changed to exclusive use of inactivated vaccine for polio, called Inactive Polio Vaccine (IPV) in short, which is administered as an injection, and is significantly more expensive than OPV.
Is it the ignorance regarding both the disease and the science of the medicine that worries critical thinkers? Yes, but more so it is the lack of freedom of questioning in a country that has effectively given itself to a form of slavery by so-called non-profit international organisations that earn millions from vaccination campaigns. The recent imposition of travel restrictions on Pakistanis as “recommended” by the World Health Organisation (WHO) are more than proof of such slavery.
Worse though is the one-sided media reporting that uses language as a tool to shape voice of dissent as “propaganda” by running headlines with terms like “anti-polio” campaigns when the questions raised are in fact directed at the safety of the vaccine claimed to be effective against polio. It’s true that oral polio vaccine’s risk of causing permanent disability is reported in only a handful of cases. Most children vaccinated with it don’t show any immediate adverse effects. However, the same holds for wild poliovirus. Less than one percent of wild poliovirus cases show any symptoms of the disease and of those permanent disability is still rare. The important question is: are parents made aware of the risks significantly early to let them make an informed decision on vaccinating their child?

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