Ans. is 'd' i.e. AFP surveillance is done in all children < 5 years of age AFP surveillance is carried out in all children below 15 years of age AFP SurveillanceAcute flaccid paralysis (AFP) surveillance is carried out to identify all remaining infected areas, monitor progress towards eradication and target supplementary immunization appropriately.The term AFP means paralysis of acute onset involving limbs leading to flaccidity. Poliomylelitis is most important etiology of AFP, other are - GBS (Guillain-Barre syndrome), transverse myelitis and traumatic neuritis.AFP surveillance aims at detecting cases of AFP and reporting them immediately to district immunization officer.Surveillance is carried out for all cases of AFP and not just for poliomyelitis. All cases of AFP are reported, regardless of the final diagnosis. As paralytic poliomyelitis is one cause of AFP, maintaining a high sensitivity of AFP reporting will ensure that all cases of paralytic poliomyelitis are detected, reported and investigated, resulting in preventive central measures to interrupt the transmission of disease.The aim of AFP surveillance is to detect polio virus transmission, and the earlier the stool is collected, the greater the chance of detecting polio virus.WHO recommends the immediate reporting and investigation of every case of AFP in children less than 15 yrs (As AFP in a person > 15 yrs is unlikely to be polio. Still, AFP surveillance must be flexible enough to report any case of AFP in an adult, if suspected to be due to poliomyelitis)Cases of AFP are classified as Polio if:Wild polio virus is isolated from any stool specimen.Cases of AFP without isolation of wild polio virus may be classified as 'polio compatible' if:Stool specimens were inadequate andResidual weakness was present 60 days after onset of paralysis or 60-day follow-up was not done (due to death or absence) and'Expert review' concludes that these cases could not be discarded as 'non-polio' based on available data.WHO recommends obtaining 2 stool samples from AFP cases within 14 days of paralysis onset and sent to WHO accredited laboratory using Reverse cold chain.AFP surveillance is evaluated by 2 key indicators :the sensitivity of reporting (target being non-polio AFP rate of at least 1 case per 100,000 children aged less than 15 years, this is the 'background' rate of AFP among children. Non-polio causes of AFP such as GBS, transverse myelitis, & traumatic neuritis account for this background rate.)the completeness of specimen collection (target being 2 adequate stool specimens from at least 80 per cent of all AFP cases).Mop-up ActivityMop-up activity is a house-to-house activity where two rounds of polio immunization, 4-6 weeks apart are conducted to limit the transmission of wild poliovirus.Under the mop-up activity, children below 5 years of age are covered in affected and neighbouring districts around every detected positive polio case.The basic strategy for eradicating polio consists of:High infant immunization coverage with four doses of oral polio vaccine in the first year of life;National Immunization Days during which every child below 5 years gets 2 additional doses of OPV on 2 days separated by 4 to 6 weeks.Surveillance of AFP to identify all reservoirs of wild polio virus transmission through reporting and laboratory testing of all cases of acute flaccid paralysis (AFP) among children under fifteen years of age;.Extensive house-to-house immunization mopping-up campaigns in the final stages where wild poliovirus transmission persists.