DES MOINES, Iowa — Pressure from medical experts and politicians mounted Thursday on Iowa Gov. Kim Reynolds to issue a statewide stay-at-home order, despite her repeated insistence that such a move isn’t necessary.Governors in most states have issued such an order, but Reynolds has argued that data shows the move isn’t needed in Iowa even though she has imposed other restrictions to slow the spread of the coronavirus.State public health officials reported Thursday that there were 66 new cases in Iowa of COVID-19, the diseased caused by the virus.