Don't miss assessing the risk of G6PD-deficiency and Hydroxychloroquine
As already commented in a response on 20.4.2020 (1), I think one of the possible reasons for more Covid-19 victims among patients and medical staff with ancestors from malaria countries could be the widespread use of chloroquine (cq) and hydroxychloroquine (hcq) for therapy and for prophylactic indications with patients with a G6PD-deficiency. Most frequently high doses up to 800 mg daily are recommended.
Although it is long known that patients with a G6PD-deficiency should not get cq or hcq, it seems to be almost forgotten with new programs and studies against covid-19. In a rapid scan of 1830 "all COVID-19 trials from the ICTRP database" (2), hydroxychloroquine or chloroquine were mentioned in 1163 of them, but "G6PD" or "Glucose-6", or "glucose-6-phosphate dehydrogenase" was only mentioned less than 100 times.
In Sub-Saharan Africa e.g. the prevalence of G6PD-deficiency (3) has been found to be 20-30% of the population. But even in Mediterranean countries the prevalence is said to be something between 2 and 20%.
Mostly men with this enzyme constellation get serous hemolysis, which is dose dependent. The symptoms would be breathlessness, microthrombosis and multi-organ failure, something that has been reported with covid-19 but was misleadingly (4) explained as a direct effect of the SARS CoV-2. In addition to this, there is a massive ramping up of hcq (5) production in Africa and India to be used off label (compassionate use).
So, if someone wants to assess the risk to ethnic minority staff, who may be at greater risk, he should have in mind, that there is a common risk in staff and patients that have ancestors from malaria regions, which has to be added to the risk of cardiac complications. The risk to assess is the use of hcq or cq in staff or patients with G6PD-deficiency.
Competing interests: No competing interests