SAO PAULO (AP) — Many countries are gingerly starting to lift their lockdown measures, and experts warn that a further surge of the coronavirus in under-developed regions with shaky public health systems could undermine efforts to halt the pandemic. They say more realistic measures to stop the outbreaks are needed. Countries like Brazil, Mexico, South Africa, India and Pakistan are easing tight restrictions before their outbreaks have peaked and also before any detailed surveillance and testing system is in place to keep the virus under control. Health experts worry that could ultimately have devastating consequences. Other experts say lockdowns were always “panic measures” and not designed to be sustainable, particularly in developing countries.