Polio vaccine contamination: Symptoms and causes of poliomyelitis, who should not get polio vaccine

Poliomyelitis, often called polio or infantile paralysis, is a highly infectious disease caused by the poliovirus that attacks the nervous system  |  Photo Credit: Thinkstock

New Delhi: Some oral polio vaccines containing 1.5 lakh vials that were administered to children in three states - Maharashtra, Telangana and Uttar Pradesh - were contaminated with strains of type-2 poliovirus. The Ministry of Health and Family Welfare taking WHO on board took immediate and comprehensive action following reports that bivalent oral polio vaccine supplied by a particular manufacturer had some quality issues. These vaccines were manufactured by a Ghaziabad-based pharmaceutical firm Biomed.

The Health Ministry, which has already issued advisories to the three states, has also clarified that the type 2 polio vaccine virus traces found in vaccine vials is not likely to cause infection. “Type 2 polio vaccine virus traces which have been found in bOPV vials is the attenuated (weakened) poliovirus and does not cause paralysis and was also earlier used in tOPV till April 2016. The recipients of such vaccine will usually shed the vaccine virus through faecal route for about 4-6 weeks after which it will die down,” the health ministry said in a statement.

“In small areas where such vials were used, polio surveillance in the environment and through stool collection has been significantly enhanced by MoHFW, with support from WHO and partners to keep a constant vigil on the shedding of the polio vaccine virus,” it added.

The ministry stated that to enhance immunity against type 2 poliovirus further, special mop-up rounds for administering IPV are being conducted in the specified areas to reach out to such children who may have missed IPV. This would provide immunity to all the children against all the three types of poliovirus including Type 2.

It may be noted that India was officially declared ‘polio-free ’by the WHO in March 2014, and the last case of wild poliovirus type 2 reported in the country was in 1999. On September 20, 2016, the Global Commission for the Certification of Poliomyelitis Eradication (GCC) concluded that wild poliovirus type 2 (WPV2) has been eradicated worldwide.

What is Poliomyelitis?

Poliomyelitis, often called polio or infantile paralysis is a highly infectious disease caused by the poliovirus that attacks the nervous system. It is transmitted through contaminated water or food, or contact with an infected person. But polio is preventable by vaccine. Children under the age of five are most at risk from contracting the poliovirus than any other group. Polio, in its most severe form, causes nerve injury, leading to paralysis and even death.

Three serotypes of poliovirus have been identified - poliovirus type 1 (PV1), type 2 (PV2), and type 3 (PV3) - each with a slightly different capsid protein. However, all three are extremely virulent and produce the same disease symptoms.

What are the signs and symptoms of Polio?

Most people who contract poliovirus are either asymptomatic or aren’t aware of the fact that they have been infected. But then, they can still spread the virus and cause infection in others.

Symptoms of non-paralytic polio: Some individuals who contract a type of polio that doesn't lead to paralysis (abortive polio) may show the following symptoms:

• Fever
• Sore throat
• Headache
• Meningitis
• Vomiting
• Fatigue
• Back pain or stiffness
• Neck pain or stiffness
• Muscle weakness or tenderness

Symptoms of paralytic polio: It is estimated that about 1% of polio cases can result in paralytic polio, which leads to paralysis in the spinal cord (spinal polio), brainstem (bulbar polio), or both. Initial signs and symptoms of paralytic polio are similar to non-paralytic polio. However, more severe symptoms may develop within a week and can include:

• Loss of reflexes
• Severe muscle aches or weakness
• Loose and floppy limbs (flaccid paralysis)
• Sudden paralysis, temporary or permanent
• Deformed limbs, especially the hips, ankles, and feet

Post-polio syndrome

Polio can return even after a person has recovered, and can occur after 15 to 40 years. Hence, it’s important to watch out for these common signs of post-polio syndrome (PPS). These may include-

• Progressive muscle or joint weakness and pain
• Muscle wasting (atrophy)
• Fatigue
• Trouble breathing and swallowing
• Sleep-related breathing disorders, such as sleep apnea
• Decreased tolerance of cold temperatures
• Depression

You must talk to your doctor and get medical help if you’ve had polio and are experiencing these symptoms Additionally, consult a child specialist if your child hasn’t completed the vaccine series. According to CDC, some people should not get the polio vaccine, for instance, if -

• the person getting the vaccine has any severe, life-threatening allergies
• the individual getting the vaccine is not feeling well.

Unfortunately, there is no cure for polio, it can only be prevented by immunisation.