A polio case has been detected in Luapula Province, in northern Zambia, making it the first case in the country since 2002.
Dr. Chitalu Chilufya, Zambia’s health minister, said the case of poliovirus type 2 (cVDPV2) was found in a 2-year-old boy who developed weakness in both lower limbs in July, and that recent tests determined he has the virus, according to the Lusaka Times.
According to the World Health Organization (WHO), 90% of people infected with polio have no symptoms or very mild symptoms. For those who do experience symptoms, these include fever, vomiting, stiffness in the neck, and pain in the limbs.
Chilufya said the health ministry is monitoring health facilities and communities in the area to mitigate the spread of the virus. He also urged parents to vaccinate their children against the virus, as the international community builds up to World Polio Day on Thursday.
The last recorded case of indigenous polio in Zambia was in 1995; while there were five cases of the wild poliovirus identified among Angolan refugees in the Western province of the country between 2001 and 2002, according to the WHO.
Vaccine-derived cases like this occur when the oral polio vaccine, which uses a live strain of the virus, mutates and causes polio — but they do not mean that the wild poliovirus is making a comeback. These cases are more so one last barrier to overcome in the fight to eradicate the disease altogether.
1. Zambia has joined the growing list of African countries that have reported cases of type 2 vaccine-derived #polio , @WHOAFRO reports. Other countries on the list include DRC, CAR, Ghana, Nigeria, Niger, Angola, Ethiopia, Benin & Somalia. pic.twitter.com/uUcbh4B2YX
— Helen Branswell (@HelenBranswell) October 21, 2019
Immunization remains key in combatting polio, and it is likely that the number of vaccine-derived cases will decrease as countries transition from using the oral vaccine to the injectable Salk vaccine (which uses a dead strain of the virus).
Polio, which is a potentially fatal and highly infectious viral disease has no cure. In the early 20th century, polio paralysed hundreds of thousands of children every year. However, it was practically eliminated as a widespread public health problem in much of the world by the 1960s because of effective vaccines.
According to Global Polio Eradication Initiative (GPEI), global incidence of polio cases has decreased by 99.9% — with an estimated 350,000 cases in 1988, to 33 reported cases in 2018.
“Conflict, political instability, hard-to-reach populations, and poor infrastructure continue to pose challenges to eradicating the disease,” states the GPEI. “Each country offers a unique set of challenges which require local solutions.”
Among the challenges is the gap in finances needed to combat the virus. The Global Polio Eradication Initiative cites an almost $3.3 billion gap in funding for the 2019- 2023 period.
On Nov. 19, Abu Dhabi will host the Reaching the Last Mile Forum, which will feature a Polio Pledging Moment where world leaders will have the opportunity to commit new funds to the GPEI.
Editor's note: This story has been edited and updated to include important information pertaining to vaccine-derived polio and the continued supported needed for polio immunization efforts around the world.