A very recent South African research team paper shows that Artemisia afra has the lowest IC50 for impairing the development of late-stage gametocytes among 8 medicinal plants species . As not many plants have such an important gametocytocidal effect, this is a really significant finding.
It confirms the in vivo results obtained in a large-scale, double-blind, randomized clinical trial in Maniema, RD Congo at the end of 2015 where Artemisia afra was among one of the test branches. Artemisia herbal tea completely eliminated gametocytes, but in 10 percent of those treated with Coartem (a prescription medicine used to treat the symptoms of Malaria), they were still present on day 28.
In 2013, Dr. Constant Kansongo in Katanga had already found in a study with 44 Plasmodium falciparum infected patients that the gametocytes had completely disappeared after 7 days of treatment with 20 gr of Artemisia afra powder containing capsules, with the exception of one patient. Artemisia afra contains no artemisinin whatsoever. The high arginine content of Artemisia plants is the best available explanation.
A paper by the Swiss Tropical and Public Health Institute (BJ Huho et al., Malaria Journal, 2012 11:118) concludes that case management with ACT may have little effect on the human population’s overall infectiousness in high perennial transmission environments. In their research, they also found that the most direct human-to-mosquito transmission measure, namely the prevalence of oocysts, was significantly higher after the implementation of ACT.
A Burkina Faso study found, 12 months after a clinical trial with ACTs, that the number of symptomatic malaria episodes was slightly higher in the ACT arm than in the control arm and that the prevalence of gametocyte carriers was the same in both arms after many treatments (AB Tiono et al.,Malaria Journal 2013, 12:79). Another research showed that the proportion of contagious children has not been substantially decreased by ACT.
After treatment, submicroscopic gametocytaemia is normal and contributes significantly to the infection of mosquitoes. (Infect Dis., 2006, 193, 1151-59, JT Bousema J). Asexual forms, mostly rings, remaining after completion of ACT may grow into mature gametocytes 7-15 days later because of the short half-life of artemisinin and because high doses induce dormancy in the asexual parasite. Some patients have gametocytemia 4-8/day at first onset after 3-day-ACT completion. What worries the study authors from Mali is not only that similar findings were found in the 2002-2004 study, but also that the baseline carriage of gametocytes was significantly higher six years after the deployment of ACTs in this area. This is also disturbing if artemisinin derivatives actually improve recrudescence and gametocyte carriage. It will suggest that in the long term, Actions would not cure malaria but strengthen it.
At the University of Leiden, Frank van der Kooy found that ArtemisiaAfra has anti-HIV properties which are stronger than Artemisia annua.