Specialists say creativity, one-on-one chats key to boosting Covid vaccination rate To hit the goal of herd immunity against Covid, vaccination rates must increase in Iowa and Dr. Megan Srinivas, an infectious disease specialist based in Fort Dodge, says creativity may be the key. “We’ve seen that incentive systems do work,” Srinivas says. “We saw in New Orleans that just having people who were willing to vaccinate during the time when people were going out at night and saying: ‘Hey, this bar is partnering with us. We’ll give you a free drink if you get your Johnson & Johnson one shot vaccine,’ was extremely effective.”