One step away from eradicating polio in the world, a new neurological disease with similar characteristics has alerted the medical community. Until now, what is known is that it is linked to enterovirus D-68 and that it can also cause acute flaccid paralysis. But its origin is still unknown, as well as the affectation it could have in the coming years.
The outbreak was detected in 2014 in California when analyzing the clinical history of five children who presented the same symptoms: paralysis in one or both arms or one or both legs and suddenly. In all cases, the severity peaked two days after the infection started. Three of them had respiratory pathology before the symptoms showed their faces and, in addition, all were vaccinated against poliomyelitis. The doctors treated these children but they did not improve. In fact, after six months the mobility of its members remained scarce. In two of them, the tests tested positive for E-68, an uncommon enterovirus associated with symptoms similar to those of polio. In the other three, the cause was not identified.
Since then, the number of people affected by this strange pathology has not stopped growing in the US. In fact, yesterday, the Centers for Disease Control updated their databases and reported that since 2014, 386 cases have been confirmed. In Europe, several have also been detected, specifically in France and Germany. In Spain, three cases were diagnosed in 2016, one of them in the Vall d'Hebron of Barcelona. The head of pediatrics at this hospital, Carlos Rodrigo, attended to this minor and although he clarifies that his patient did affect his paralysis, he calls for calm: "The majority of those who contract the virus only have respiratory symptoms, infections type bronchitis, but nothing more ». What happens, Rodrigo continues, "is that some patients without knowing why, go further."
The pediatrician explains that this paralysis or myelitis is caused by an inflammation in some part of the marrow, "which acts as a center for the transfer of information from the brain to the rest of the body." This swelling "affects the gray matter and destroys the cells responsible for transmitting the current." The paralysis due to bone marrow involvement is different from that which originates in the brain, as happens with stroke, for example: "In these cases the extremities become hypertonic, while with polio or D-68 the muscle tone is flaccid ».
The cause of why only a few of those who get this disease develop myelitis is unknown – in the US, of the 386 cases, at least 62 suffered it. But Rodrigo believes that this "should not surprise us": "When polio became an epidemic, the same thing happened. Only 1 in 100 had symptoms and only 1 between 100 and 1,000 had paralysis without knowing the reason. "Perhaps certain genetic factors predispose the child to develop the most serious picture, but we must bear in mind that this also occurs with cancer and with a host of other diseases."
This new pathology affects mainly pediatric patients and although the cause is not well known "one of the theories is that adults have already been in contact with the enteroviruses that cause it and have created antibodies," says Rodrigo. But, as happened with polio, "you can run the risk that if you contract as an adult, it is more serious." However, "there have not yet been enough cases to study it". That same reason explains that still the scientific community has not achieved a vaccine to eradicate it. Although if the predictions are fulfilled they will have to get down to work: according to the estimates of the US Center for Disease Control, in less than a decade there could be more than one million affected in this country alone.
The good news, says the head of pediatrics Vall d'Hebron, is that "much more is known about it than other pathologies much more widespread." The reason? «That it is a virus from the same family of polio and as in Europe there is a program for its eradication that requires studying and analyzing all children under 15 years of age who have acute flaccid paralysis, to see if they have poliomyelitis or what a virus, we are very prepared for its existence and we know where to look ». A task in principle not easy because, as Rodrigo says, unlike what you can think "although the problem is neurological, in its most severe forms is only its trace in respiratory samples and feces." This specialist insists on lowering the alarm: "In very few cases this neurological disease ends in paralysis and also in Spain, due to our trajectory, we are very prepared".
Rodrigo, as Head of Pediatrics of the Vall d'Hebron, is in contact with the rest of the reference hospitals to report the cases that are appearing and to investigate their evolution. But, fortunately, unlike what happened with polio, in the event that at some point it becomes an epidemic, we have the scientific instruments necessary to contain it. By the way, poliomyelitis is only endemic in three countries: Nigeria, Pakistan and Afghanistan. In the rest of the world, its transmission has been halted.