Fig 1.
We identified 272 women who had one or more vivax malaria episodes during pregnancy diagnosed and treated with chloroquine alone between January 2014 and September 2016, and were not administered weekly chloroquine prophylaxis after treatment. Reasons for exclusion and the final number of subjects analyzed are indicated.
Fig 2.
Time-to-recurrence over 12 months of follow-up in PQ-untreated pregnant women and PQ-treated non-pregnant control experiencing a primary vivax malaria episode.
The shaded areas indicate the 95% confidence bands. PQ-untreated pregnant women were eligible for the second recurrence analysis if PQ was not given to treat the first episode. (A) Time to first vivax malaria recurrence, control vs. pregnant women; (B) Time to second vivax malaria recurrence, control vs. pregnant women; (C) Time to first recurrence vs. time to second recurrence, control women; (D) Time to first recurrence vs. time to second recurrence, pregnant women.
Fig 3.
Fitting of the mathematical model (Eqs 1 and 2) to the time to the first P. vivax recurrence over 1-year follow-up in PQ-untreated pregnant women and PQ-treated non-pregnant controls.
Fig 4.
Cumulative distribution function of first vivax malaria recurrences among PQ-untreated pregnant women and PQ-treated non-pregnant controls.
(A) First recurrence in pregnant women; (B) First recurrence in control women. The dark grey area in the graphs represents the proportion of subjects experiencing relapses/recrudescences and the light grey area represents the proportion of subjects experiencing new infections.
Fig 5.
Simulation of the potential effectiveness of post-treatment chemoprophylaxis with weekly chloroquine (CQ) to prevent P. vivax recurrences after a primary infection.
We considered scenarios with CQ prophylaxis being given over 4 (panels A, B and C), 8 (panels D, E and F) or 12 (panels G, H and I) weeks, being able to suppress 60% (panels A, D and G), 80% (panels B, E and H) or 100% (panels C, F and I) of blood-stage infections (regardless of its origin, whether hypnozoite- or mosquito bite-derived) during the period of administration. Dashed lines (“Ref.”) represent the scenario without intervention; the dark grey area represents the cumulative proportion of subjects with P. vivax relapses/recrudescences over time and the light grey area represents the cumulative proportion of subjects with new P. vivax infections.