New research suggests a one-two punch could help battle polio in some of the world's most remote and strife-torn regions: Giving a single vaccine shot to children who've already swallowed drops of an oral polio vaccine greatly boosted their immunity. The World Health Organization officials said the combination strategy already is starting to be used in mass vaccination campaigns in some hard-hit areas and is being introduced for routine immunizations in developing countries, too. "It could play a major role in completing the job of polio eradication once and for all," said Dr. Hamid Jafari, WHO's director of polio operations, who led the study published Thursday in the journal Science.
The number of countries where polio regularly circulates dropped from 125 in 1988 to just three as of last year — Pakistan, Nigeria and Afghanistan. But with travel, the threat is re-emerging in countries previously free of the highly contagious virus. The WHO in May declared an international public health emergency, citing outbreaks in at least 10 countries. Particularly of concern were Syria, Somalia and Iraq, where violence has complicated efforts to contain new cases.