February 24, 2014
LONDON: In what could be the biggest blow in recent years to the global fight against polio, fears have now emerged that the crippling disease has returned to America after 35 years.
Polio is a highly contagious disease and has been wiped out from the developed world decades ago. India recorded its last case three years back.
February 24, 2014
LONDON: In what could be the biggest blow in recent years to the global fight against polio, fears have now emerged that the crippling disease has returned to America after 35 years.
Polio is a highly contagious disease and has been wiped out from the developed world decades ago. India recorded its last case three years back.
Researchers have identified a polio-like syndrome in a cluster of children from California over a one-year period. A detailed analysis of five cases showed enterovirus-68 — which is related to poliovirus — could be to blame.
Interestingly, all the children had been vaccinated against polio. Symptoms have ranged from restricted movement in one limb to severe weakness in both legs and arms.
The cases have been spread over a 100-mile diameter (160km) so the research team do not think the virus represents a single cluster or outbreak.
Polio is a highly contagious disease and has been wiped out from the developed world decades ago. In case the virus returns to this region, it will throw back all progress made to eradicate the disease by half a century. In the late 1940s to the early 1950s, polio crippled an average of more than 35,000 people in the United States each year.
However the United States has been polio-free since 1979.
In 1994, the entire WHO Region of the Americas was certified polio-free. In a highly worrying development, US doctors have warned of an emerging polio-like disease in California where up to 20 people have been infected.
A meeting of the American Academy of Neurology has been told today that some patients had developed paralysis in all four limbs, which had not improved with treatment.
Polio was recently eradicated from India leaving it endemic only in three countries — Afghanistan, Nigeria and Pakistan.
"Although poliovirus has been eradicated from most of the globe, other viruses can also injure the spine, leading to a polio-like syndrome," said case report author Keith Van Haren, with Stanford University and a member of the American Academy of Neurology.
"In the past decade, newly identified strains of enterovirus have been linked to polio-like outbreaks among children in Asia and Australia. These five new cases highlight the possibility of an emerging infectious polio-like syndrome in California".
Van Haren said he and his colleagues noticed several of these cases at their medical centers and decided to look for similar cases in California. They reviewed all polio-like cases among children who had samples referred to California's Neurologic and Surveillance Testing program from August 2012 to July 2013.
Cases were included in the analysis if the children had paralysis affecting one or more limbs with abnormal MRI scans of the spinal cord that explained the paralysis. They did not include children who met criteria for Guillain-Barre syndrome and botulism, which can cause similar symptoms.
The five children experienced paralysis of one or more arms or legs that came on suddenly and reached the height of its severity within two days of onset. Three of the children had a respiratory illness before the symptoms began. All of the children had been previously vaccinated against poliovirus.
The children were treated but their symptoms did not improve and they still had poor limb function after six months. Two children tested positive for enterovirus-68, a rare virus previously associated with polio-like symptoms. No cause was identified in the remaining three children.
"Our findings have important implications for disease surveillance, testing and treatment," said Van Haren. "We would like to stress that this syndrome appears to be very, very rare. Any time a parent sees symptoms of paralysis in a child, the child should be seen by a doctor right away".
CDC Atlanta says it is crucial to maintain the success rate of US vaccination efforts since the disease still exists in some parts of the world. People most at risk are those who never had polio vaccine, those who never received all the recommended vaccine doses, and those traveling to polio endemic countries.
Courtesy: TNN
