Here is something of fundamental malariological interest:
A past suggestion is that both early and late homologous recurrences of Plasmodium vivax malaria can have a non-circulating merozoite origin [1–4].
There is now revealing new (February 2021) evidence which supports this idea. Some post-28-day recurrences that took place during a recent study appeared to be recrudescences rather than relapses . Thus, it seems likely that a combination of the two types of recurrence can occur after 28 days.