Last May, as the first cases of Zika were being detected in Brazil, cities at the frontlines of the epidemic stopped receiving government shipments of insecticide to kill mosquitoes.

In Campina Grande, a city of 400,000, the shortages continued even after President Dilma Rousseff declared the mosquito-borne virus a national health emergency on Nov 11.

The lack of larvicide is one of a string of public health failings crippling Brazil's ability to manage the Zika outbreak and the surge in rare birth defects believed linked to it. A weeklong tour by The Associated Press of the impoverished northeast where the epidemic is most severe found public hospitals starved for funding and local officials scrambling to care for the stricken babies.