Polio Has Returned to the Philippines

The New York Times is reporting that health authorities in the Philippines have announced the first case of polio in 19 years. According to the article:

“Health Secretary Francisco Duque said government scientists have confirmed the “re-emergence of polio” after one case in the southern province of Lanao del Sur and another suspected case of the disease. He blamed “poor immunization coverage,” a lack of sanitation and proper hygiene and poor surveillance by health workers as among the reasons the disease returned.

Polio is an infectious disease that can spread rapidly and mainly affects young children. It can cause muscle weakness, paralysis and, on rare occasions, it can be fatal. There is no cure for polio, but it can be prevented with multiple doses of polio vaccines.

Despite aggressive eradication efforts around the world, the disease has hung on in a handful of countries and even gained a stronger foothold in some, like Pakistan and Afghanistan. There are currently cases this year in several African countries, such as the Central African Republic and Somalia.

Mr. Duque said on Thursday that the case in Lanao del Sur involved a 3-year-old girl. Apart from that confirmed case, a case of “acute flaccid paralysis” thought to also be polio was awaiting confirmation, he said.”

In the United States, a locally acquired case of polio has not been documented since 1979, according to the Centers for Disease Control and Prevention (CDC). However, because there are still small pockets of the disease in different parts of the world, children in the US are immunized with the inactivated poliovirus vaccine (IPV) in four doses at childhood. In other parts of the world, where polio is yet to be eliminated or there is a high risk of an epidemic if the virus is reintroduced by travelers, the oral poliovirus vaccine (OPV) is still given.

Any kind of decrease in polio vaccine coverage can trigger an outbreak because one case of polio can infect between 5 and 7 other people (usually children). Based on this level of transmissibility, the threshold of vaccination needed for community immunity is around 85%. In recent years, the Philippines has encountered a wave of anti-vaccine sentiment. A recent dengue vaccine proved to be ineffective and triggered an excess number of injuries. Based on this, many parents stopped vaccinating altogether, leading to an explosion in the number of measles cases and an eventual appeal from President Duterte for parents to immunize their children.

Along with measles cases numbering in the thousands — and deaths in the hundreds — public health authorities in the Philippines are facing numerous obstacles in their response to this polio cases. The biggest obstacle will be restoring public trust after the dengue vaccine controversy. After all, in any society, if the public does not trust public health, it is very difficult to conduct any kind of public health program.

Author: René F. Najera, DrPH

I am the editor of the History of Vaccines site, an online project by the College of Physicians of Philadelphia. All opinions expressed on these blog posts are not necessarily those of the College or any of my employers. Check out my professional profile on LinkedIn: https://www.linkedin.com/in/renenajera Feel free to follow me on Twitter: @EpiRen