Brazil's new health minister is going on the offensive to dispel worries about the country's Zika outbreak, which has cast a pall over the upcoming Rio de Janeiro Olympics. Ricardo Barros insists the Aug. 5-21 games will be safe and there's minimal risk of contracting Zika for the 350,000-500,000 expected foreign visitors. The mosquito-borne virus has been linked to a surge in Brazil of the birth defect microcephaly, AP reported. Barros said mosquito populations drop significantly in August, a winter month in the Southern Hemisphere. He spoke Friday at the second news conference this week aimed at soothing concerns about Zika. Olympic, state and city officials made the same arguments earlier this week.