‘Fourth wave’: As mask mandates are lifted, Arizona health researchers urge Covid-19 caution

Health researchers on Wednesday urged caution despite the state’s lifting of restrictions on businesses and government, echoing a federal warning of a possible fourth wave of Covid-19 if Arizonans become too complacent. Dr. Joshua LaBaer, executive director of the Biodesign Institute at Arizona State University, ticked off positive developments, bookended by warnings. Vaccinations are rising and cases of Covid-19 “at a minimum” slowed and stabilized in recent weeks, he said. But new variants,…