In the early days of the coronavirus pandemic, the harried health officials of Peru faced a quandary. They knew molecular tests for Covid-19 were the best option to detect the virus – yet they didn’t have the labs, the supplies, or the technicians to make them work.But there was a cheaper alternative – antibody tests, mostly from China, that were flooding the market at a fraction of the price and could deliver a positive or negative result within minutes of a simple fingerstick.In March,…