Polio Eradication: How to Achieve It?

Polio currently poses a major challenge for Pakistani children and future generations. The modern world has successfully eradicated this debilitating disease, securing a healthier future for its children. Regrettably, Pakistan and Afghanistan remain the only two countries where polio cases persist. Alarming still, nuclear-capable Pakistan leads the world in polio cases.

Polio Myelitis: An Overview
The term “Polio Myelitis” originates from Greek, meaning “inflammation of the grey matter,” named by the German physician Adolf in 1874. This disease affects the nervous system’s grey matter, causing inflammation and often leading to paralysis. Initially called “infantile paralysis,” the early history of polio remains uncertain, though evidence suggests a history spanning thousands of years. For instance, ancient Egyptian carvings depict a man walking with a stick due to a weakened leg and foot, characteristic of polio.

The first medical description of polio was documented by British physician Michael Underwood in 1789, and it was later recognized as a specific condition by Jacob Heine in 1840. Polio’s first modern epidemic emerged with urbanization following the Industrial Revolution, becoming an unusually virulent disease.

The Early 20th Century Polio Outbreaks
Around 1905, major polio outbreaks appeared in Norway and Sweden. The United States faced a severe outbreak in 1916, recording over 9,000 cases and 3,432 deaths. Throughout the 20th century, polio spread widely; in 1952 alone, the United States saw a record 62,857 cases. Franklin D. Roosevelt, diagnosed with polio at 39, spent his life in a wheelchair, yet his perseverance became a symbol of hope for polio survivors.

What is Polio?
Polio is a highly contagious disease caused by the poliovirus, primarily affecting children under ten and potentially causing permanent paralysis in the lower limbs. The virus spreads through human contact, often in unsanitary conditions, entering the body through contaminated food or water. Once in the intestines, it can invade the nervous system and lead to paralysis, which is often irreversible and can sometimes be fatal. While there is no cure for polio, vaccination effectively protects children from this crippling disease.

Types of Poliovirus
Polio has two primary forms: Wild Poliovirus (WPV) and Vaccine-Derived Poliovirus (VDPV). Both types have three subtypes. Currently, Pakistan is affected by WPV Type 1 and circulating VDPV Type 2. The virus spreads through contaminated food and water, multiplying in the digestive system, where it can enter the bloodstream and attack the nervous system. About 1-2% of infected individuals develop paralysis.

Interestingly, the poliovirus only affects humans. WPV Types 1 and 2 were eradicated globally in 1999 and 1912, respectively. The incubation period, from virus entry to symptom onset, lasts up to 10 days, with most infections showing no immediate symptoms.

Types of Polio
1.Non-Paralytic Polio:

In some cases, symptoms are mild and do not lead to paralysis. They can last up to 10 days and include fever, sore throat, headache, nausea, fatigue, and muscle weakness.
2.Paralytic Polio:

This rare but severe form causes paralysis. Initial symptoms may resemble non-paralytic polio, but within a week, severe pain, muscle weakness, and even limb flaccidity may develop.
3.Post-Polio Syndrome (PPS):

This condition emerges years after initial polio infection, affecting muscles and joints. Symptoms include muscle weakness, fatigue, muscle shrinkage (atrophy), breathing and swallowing difficulties, and reduced body temperature.

Diagnosis
Doctors diagnose polio based on symptoms like neck and back stiffness, difficulty swallowing, and breathing issues. Additional tests, such as throat swabs, stool analysis, and spinal fluid examination, are also used for confirmation.

Treatment
As there is no cure for polio, supportive care is critical. Patients with severe infections may require ventilators if respiratory muscles are affected. Physical therapy, massage, and exercise are crucial for maintaining muscle strength. Pain relief and fever management are also part of care. Vaccination remains the most effective prevention method. Polio vaccines include oral polio vaccine (OPV) and inactivated polio vaccine (IPV).

Polio Vaccines
– Oral Polio Vaccine (OPV): OPV is cost-effective, safe, and offers long-lasting protection. While the virus is live, it lacks the ability to cause disease, providing quick immune response and sustained protection.
– Inactivated Polio Vaccine (IPV):Used primarily in developed countries, IPV contains inactivated virus, eliminating the risk of vaccine-derived infection. IPV may cause mild allergic reactions in some individuals.

Global Polio Eradication Efforts
The World Health Organization (WHO) launched the Global Polio Eradication Initiative (GPEI) in 1988. At the time, there were around 350,000 cases worldwide across 125 countries. By 2018, polio cases had decreased by 99%, a monumental achievement. WHO declared the Americas polio-free in 1994, followed by the Western Pacific Region in 2000, Europe in 2002, Southeast Asia in 2014, and Africa in 2020.

WHO recognizes regions rather than individual countries as polio-free. To qualify, a region must meet these criteria:
1. Three consecutive years with no local polio cases.
2. A reliable monitoring system.
3. The ability to detect and investigate imported cases.

Pakistan has been striving for eradication since 1994 with the Polio Eradication Program, which employs nearly 270,000 trained workers to administer vaccines. Pakistan recorded the highest number of cases globally in 2011 with 198 cases.

With significant international support, Pakistan continues its polio eradication efforts, despite temporary suspension due to COVID-19 in 2020. After resuming in July 2020, vaccination campaigns reached over 3.4 million children across 100+ districts.

Polio Eradication Challenges
Only two wild poliovirus strains remain, and the world is on the cusp of eradicating the disease entirely. However, polio remains a public health threat in Pakistan and Afghanistan.

Global Health Regulations
The International Health Regulations identify Pakistan as a region affected by polio, with risks of global spread. For travelers to and from high-risk areas, vaccination is mandatory.

Conclusion
The annual World Polio Day, observed on October 24, reminds us of polio’s impact. Pakistan’s polio vaccination schedule for children under five includes doses administered at birth, six weeks, 10 weeks, and 14 weeks. Additionally, a regional or national campaign ensures full vaccination for all children, even those who have already received their scheduled doses.