The number of polio cases in the country has shown a decline but there has been a sharp rise in AFP (Acute Flaccid Paralysis) cases as is evident from non polio AFP rates (Table 1) (1). A sensitive surveillance system detects a rate of 1 per 1 lakh children less than 15 years old. Non polio AFP rate in India has exceeded 5 while that in Bihar and UP have touched figures of 10.9 and 11.2 respectively(1). Values exceeding one need introspection and careful evaluation.

Prodromal infections or vaccines in several reports have been found to be temporally followed by a new onset of autoimmune diseases. This has been accepted for diphtheria and tetanus toxoid, polio and measles vaccines and GBS (Guillain Barre Syndrome)(2).

Several studies have been conducted on GBS or its relation with nation wide oral polio vaccination. Results have demonstrated a temporal association between polio virus infection caused by either wild virus or live attenuated vaccine, and an episode of increased occurrence of GBS. However, they cannot prove the suspected cause- effect relation between GBS and OPV administration(3,4).

Molecular characterization of polio virus isolated from paralysis cases of GBS, transverse myelitis and facial paralysis have confirmed the vaccine origin of the strain and demonstrated mutation known to increase neurovirulence. This suggests that the Sabin-vaccine–derived poliovirus strains could also trigger such diseases(5).

Increase in non-polio AFP rates thus mandates exploring the causes of such cases as this might have perplexing implications for immunization program.

Sutapa Bandyopadhyay Neogi,
C3A/33A, Janakpuri,
New Delhi 110 058, India.
E-mail: [email protected]  

1. AFP Surveillance Bulletin- India. Available at: www.npspindia.org. (Accessed on Oct 25, 2005).

2. Molina V, Shoenfeld Y. Infection, vaccines and other environmental triggers of autoimmunity. Autoimmunity 2005; 38: 235-245.

3. Kinnunen E, Junttila O, Haukka J, Hovi T. Nationwide oral polio virus vaccination campaign and the incidence of Guillain Barre Syndrome. Am J Epidemiol 1998; 147: 69-73.

4. Ismail EA, Shabani IS, Badawi M, Sanaa H, Madi S, Al-Tawari A, et al. An epidemiologic, clinical and therapeutic study of childhood Guillain-Barre syndrome in Kuwait: Is it related to the oral polio vaccine? J Child Neurol 1998;13: 488-492.

5. Friedrich F. Rare adverse events associated with oral poliovirus vaccine in Brazil. Braz J Med Biol Res 1997; 30: 695-703.