Polio was a global scourge as recently as three decades ago. Since then, it has been on the decline worldwide. Polio has now been eradicated in the wild from all but two countries. We wonder: Which countries still have not halted transmission of polio from the wild?
A. Afghanistan is correct.
Since September 2015, Afghanistan is one of just two countries worldwide in which polio is still endemic. This means the disease can be contracted from the wild, and not just from an infected person.
Polio is spread by person-to-person contact, especially in environments with poor sanitation and hygiene. Children under the age of five are especially susceptible. The disease can result in permanent paralysis and is sometimes fatal.
In 2013 and 2014, polio outbreaks were reported in at least ten countries — mostly in South Asia and Africa. However, in most of those countries, the virus arrived from outside the country.
The 28 documented cases of wild polio in Afghanistan in 2014 were double the 14 cases in 2013. Almost all of the Afghan cases occurred in the eastern region bordering Pakistan.
In September 2015, Afghanistan – along with 126 other countries — introduced the inactivated polio vaccine, a weaker version that is easier to transport to and deliver in remote regions. The hope is that every Afghan child under a year old will be able to receive it.
In 1988, the World Health Organization, Rotary International, UNICEF and the U.S. Centers for Disease Control (CDC) founded the Global Polio Eradication Initiative. At the time, worldwide, there were 350,000 new cases of polio paralyzing people each year.
Most of these new cases occurred among children in the world’s developing countries, where vaccination rates were extremely low. Since then, there has been a 99% reduction in the disease.
B. Pakistan is also correct.
Beyond Afghanistan, neighboring Pakistan is the other country where polio infections from the wild remain endemic. In 2014, there were 306 documented cases of wild polio in Pakistan — 85% of all new cases worldwide.
Most of Pakistan’s new cases of polio occur in the Taliban-controlled northwestern part of the country, where health workers have been murdered due to their vaccination efforts. CIA interference in general vaccination efforts during the search for Osama Bin Laden did not help community relations with health NGOs.
About 90% of people infected with the polio virus have no symptoms — or have very mild symptoms that often go undiagnosed. As such, they become “silent carriers” of the virus and can spread it unwittingly.
The development and widespread use of polio vaccines in the 1950s led to the virtual eradication of the disease in North America and Europe. The last outbreak of the disease in the United States occurred among Amish populations in the U.S. Midwest in 1979.
The last outbreaks in Western Europe occurred in the 1980s in Spain. Sporadic outbreaks in the former Soviet bloc countries of Eastern Europe continued until the early 2000s. Europe was finally declared polio-free in 2002.
C. Iraq is not correct.
The World Health Organization declared Iraq polio-free in 1990. The country remained free of the disease during the ten years of war that followed the U.S.-led invasion in 2003.
However, in early 2014 health workers confirmed two new cases of polio in Iraq. The polio virus in those cases appears to have spread from neighboring Syria, which in turn got it from Pakistan.
The Syrian civil war destroyed the public health infrastructure required to ensure widespread vaccination of children. Similarly, two cases of non-wild polio appeared in Ukraine in 2015, likely due to the war there.
International health workers have conducted many rounds of child vaccinations in Syria and Iraq since late 2013. Their efforts are severely hindered by the region’s violence and conflicts.
D. Nigeria is no longer correct.
In September 2015, the World Health Organization removed Nigeria from its list of countries with endemic polio. Its last reported case of the virus contracted from the wild was in July 2014.
Polio has now been declared officially eradicated in the wild from Nigeria after 12 months of negative lab tests.
This does not mean Nigeria is “polio-free.” One case of non-wild polio had been reported in 2015 as of mid-December. Additionally, polio could also still be transmitted from someone outside the country. But wild eradication puts Nigeria close to that goal.
In recent years, community and religious leaders, government officials, public health workers and volunteers had worked together to vaccinate 45 million Nigerian children.
As in Afghanistan and Pakistan, most of Nigeria’s new polio cases occurred in parts of the country in which violent conflicts had thwarted vaccination efforts.
The 53 documented cases of polio in 2013 occurred in Nigeria’s northern states, where the militant group Boko Haram resists all government activities and targets health workers for assassination.