(Adds comments on vaccine rollout, details of inflation report) BRASILIA, Dec 17 (Reuters) - Questions about the rollout and acceptance of COVID-19 vaccines in Brazil are adding uncertainty to economic forecasts, Central Bank President Roberto Campos Neto said on Thursday while discussing the bank’s quarterly inflation report. Brazil’s government faces sharp questions about how soon it will begin a national immunization program, as new cases rise again in the world’s second-deadliest outbreak. The health minister said on Thursday that Pfizer’s efforts to get emergency approval for its vaccine had hit a regulatory snag. “We have to wait a little to see the result of what’s being done, how the logistical part of the vaccination advances and, furthermore, what will be the reaction of the population once the vaccination is underway,” Campos Neto told journalists. President Jair Bolsonaro, one of the world’s most prominent COVID-19 skeptics, has said he will not take any vaccine, stoking resistance to vaccines in a country that once served as a model of national immunization efforts. Nearly a quarter of Brazilians now say they are unwilling to take any COVID-19 vaccine, up from just 9% in August. Half would refuse the shot developed by China’s Sinovac Biotech — one of the two vaccines to be produced in Brazil. The central bank said in its quarterly inflation report that a speedy vaccination campaign could unlock repressed demand, restore confidence in the economy and push up prices faster than in the bank’s base scenario. On the other hand, the bank’s analysts calculated that a more drawn out pandemic would weigh on growth and knock a full percentage point off inflation next year, lowering it to 2.4%. “If there were a delay to vaccination resulting in lower mobility because the number of cases is higher, obviously that will have an impact on economic activity,” Campos Neto said. “Today nothing suggests that that will happen.” (Reporting by Marcela Ayres Editing by Brad Haynes and Grant McCool)