What is the treatment of chronic Vivax malaria?
Blood stage infection with Plasmodium vivax can usually be treated successfully with chloroquine, though resistance is spreading in some areas (notably the Pacific Islands, Papua New Guinea, parts of south-east Asia and especially Indonesia, and Peru). P. vivax is also sensitive to artemisinin-based combination therapies (ACTs) and as no resistance to artemisinin has been reported, these are widely recommended (though combinations which include sulfadoxine-pyrimethamine should be avoided as many strains of P. vivax appear to be resistant to pyrimethamine).
Liver stage (i.e. relapsing) P. vivax can only be treated with one drug: primaquine. Instances of liver stage treatment failure are relatively commonplace, and may be strain or dosage dependent. Primaquine is not recommended for people with G6DP deficiency, so potential patients, and particularly those from locations or ethnic groups known to have high levels of G6DP deficiency, should be tested prior to treatment.