In an article published in The Lancet, Dr. T Jacob John, the doctor who pushed for the pulse polio campaign, and Dr. Dhanya Dharmapalan, Mumbai based pediatrician underlined that the wild poliovirus follows the respiratory transmission or airborne route. Dr, John stated that during the ‘80s and the ’90s, wild virus polio was not prevalent in rich countries, whereas low-income countries had polio as well as poor sanitation/hygiene, consequent diarrheal diseases, etc. Hence, the experts surmised that natural polio was spread through the fecal-oral route. 

Strategies based on the guess that polio is transmitted through the fecal-oral route did not work completely and the Global Polio Eradication Initiative had to set a new target of 2026.  Dr. Dharmapalan stated that polio infection has been noted in infancy during exclusive breastfeeding, with a basic reproduction number of wild poliovirus in the range of 40-45. On the other hand, the reproduction number of measles is 30. “Hence, polio is more contagious than measles”, stated Dr. Dharmapalan. 

Dr, Mangala Gomare, BMC executive health officer stated that the best course of action would be to promote IPV (three doses per child) and to withdraw OPV from countries that have reached 85%  coverage in children younger than five years. Dr. Nitin Shah, Indian Academy of Pediatricians, explained that the injectable vaccine should be given as a part of a six-vaccine-in-one-shot in the 6th, 10th, and 14th weeks. Thereafter, children should receive two boosters at 15 to 18 months and 5 years of age.

(Source: https://health.economictimes.indiatimes.com/news/industry/polio-spreads-through-air-need-injectable-rather-than-oral-vaccines-now-say-experts/92871195 )