Could polio make a comeback?

by Melissa Beattie Moss
Could polio make a comeback?
Two children with polio, in the Democratic Republic of Congo. Credit: World Health Organization

It's one of the most famous global public health success stories of the 20th century: the near-eradication of polio, the dreaded childhood disease that paralyzed or killed more than half a million people around the world annually at its peak in the 1940s and 50s. Following mass immunization campaigns with two kinds of polio vaccine—Jonas Salk's inactivated polio virus and Albert Sabin's live-attenuated vaccine—the annual number of polio cases plummeted in the United States.

The fight against in developing nations has been a more protracted battle, but great strides have been made. Since the 1988 World Health Assembly resolution to eradicate the disease, polio cases worldwide have dropped to fewer than 700.

However, in early May 2014, the World Health Organization (WHO) released a statement pointing to an alarming spike in the international spread of wild poliovirus, originating from three "hot spot" nations, Pakistan, Syria and Cameroon. The WHO called this an "international health emergency" requiring "extraordinary measures."

Could we be facing another polio epidemic?

"Vaccination protects against the disease for a lifetime," says Craig Cameron, who holds Penn State's Eberly Chair in Biochemistry and Molecular Biology. "And the WHO, Centers for Disease Control and their partners have the will to vaccinate every individual that can be reached.

The problem is access, which remains difficult in some cases. Often it's war that is a major limitation. Sometimes the barrier is due to ignorance, but in others to stupidity. In some countries, governments still feel that this effort is contrived to do harm to their people."

Until this year, global vaccination campaigns—at a cost of up to one billion dollars per year—have kept the transmission rates very low, notes Cameron. So what has changed recently? Experts point to disruptions such as the war in Syria, which has interrupted vaccination programs and allowed the virus to return. In Pakistan, the Taliban has attacked workers trying to vaccinate children.

The WHO concurs that "Pakistan, Cameroon, and the Syrian Arab Republic pose the greatest risk of further wild poliovirus exportations in 2014," and has urged that "all residents and long-term visitors receive a dose of at least a month before traveling internationally and should require proof of vaccination to travel."

The risk for citizens in more economically developed nations remains very low, stresses Cameron. "Outbreaks in this country do occur on rare occasion," he notes, especially among communities that do not vaccinate (the Amish are a notable example). However, for the general population, "as long as one gets vaccinated, there is no need to worry about your personal risk."

That doesn't mean there's no cause for worry about the larger global picture. After the International Health Regulations committee convened an emergency meeting in late April 2014, the WHO issued the unequivocal statement that "if unchecked, this situation could result in failure to eradicate globally one of the world's most serious vaccine preventable diseases." The committee unanimously agreed to declare the surge of polio a "Public Health Emergency of International Concern."

It's sobering news, agrees Cameron. "There are many of us that believe it will be impossible to eradicate poliovirus globally because of the sociopolitical circumstances such as those that we are witnessing at present."

add to favorites email to friend print save as pdf

Related Stories

WHO starts emergency polio talks

Apr 28, 2014

The World Health Organization announced on Monday that it had convened emergency talks amid rising concern over polio after cases were discovered in Afghanistan, Iraq and Equatorial Guinea.

WHO declares polio 'public health emergency' (Update)

May 05, 2014

The World Health Organization warned Monday that polio has reemerged as a public health emergency, after new cases of the crippling disease began surfacing and spreading across borders from countries like ...

Recommended for you

Cerebral palsy may be hereditary

5 hours ago

Cerebral palsy is a neurological developmental disorder which follows an injury to the immature brain before, during or after birth. The resulting condition affects the child's ability to move and in some ...

19 new dengue cases in Japan, linked to Tokyo park

11 hours ago

Japan is urging local authorities to be on the lookout for further outbreaks of dengue fever, after confirming another 19 cases that were contracted at a popular local park in downtown Tokyo.

User comments