Brazilian President Jair Bolsonaro neatly sums up how thoroughly politics has hijacked the debate over using malaria drugs against the new coronavirus: "Right-wingers take chloroquine."

Based on preliminary studies in China and France -- and, apparently, a heavy dose of hope for something other than economically painful lockdowns to contain the pandemic -- Trump and Bolsonaro have been touting chloroquine and hydroxychloroquine as potential wonder drugs against Covid-19, despite scientists' insistence that further testing is needed.

Brazil's former health minister Nelson Teich resigned last week after less than a month on the job, reportedly after clashing with Bolsonaro over the president's insistence on expanding the use of chloroquine against Covid-19.

Political analysts predicted Bolsonaro, now on his third health minister of the pandemic, would seek a pliable replacement willing to ignore the lack of scientific evidence on chloroquine.

The new guidelines recommend doctors in the public health system prescribe either chloroquine or hydroxychloroquine from the onset of symptoms of coronavirus infection, together with the antibiotic azithromycin.