Background:
Our study:
My job:
- Malaria has nearly been eliminated in Zanzibar (reaching historically low prevalences).
- Pregnant woman, especially during their first two pregnancies, are particularly susceptible to malaria sequestering in the placenta.
- Blood tests of peripheral parasitemia (peripheral = in the blood circulating around the whole body, parasitemia = the parasites that cause malaria) do not reveal the presence of placental parasitemia, but peripheral blood tests are the only ones that are systematically done to monitor malaria rates in Zanzibar and elsewhere.
- In areas of stable, high rates of malaria transmission (which it what Zanzibar was a few years ago), it is recommended by the WHO that all women receive a particular chemoprophylactic (chemo- = chemical, prophylactic = preventative) regimen called IPTp = Intermittent Preventive Treatment in pregnancy using a combination drug called SP = sulphadoxine-pyrimethamine. One dose of SP is given once after quickening, and then a second dose a month after the first dose; a third dose is recommended for HIV-positive mothers (of which there are relatively few in Zanzibar). However, no recommendations have been set for areas with historically high transmission rates but where those rates have been significantly reduced.
Our study:
- After pregnant women who have NOT received even one dose of SP as a part of IPTp give birth, but before the placenta is discarded by the medical staff, we will take a small blood sample from the placenta and check for parasitemia. This will help us judge the prevalence of placental parasitemia among women who do not receive IPTp, and therefore help us judge what the prevalence would be in the population if IPTp were not recommended for all pregnant women.
- We will try to use this data along with a cost-benefit analysis to inform a decision as to whether IPTp should be continued as a general prophylactic method to keep malaria rates down.
My job:
- Design the study (there was already a basic design in place; I am fiddling with details, doing sample size calculations, etc)
- Get ethical clearance
- Design data collection tools
- That kind of stuff.
And, thus far, I love my job.
What a neat and informative post! But I'm afraid I might sound like a poor reader in asking whether you've already obtained IRB approval for your protocol, because it sounds like from your description that you're doing work leading up to the creation of the study design for a proposed protocol. Correct? If the informed consent document you eventually write (or is it already written) is allowed to be shared, I'd love to read it! (Have you encountered the ethical dispute about the 076 study about AZT therapy for pregnant women in your coursework?)
ReplyDeleteGreat questions! The study was generally proposed and designed for the sake of obtaining funding, which is a different process from (and often predecessor to) obtaining ethical clearance. We have only done the former.
ReplyDeleteOur study is strictly observational. We know IPTp is effective; another arm of the organization is a part of scaling up the number of women who receive IPTp as a part of their antenatal care. However, we do not know if women are really still at enough risk in a low prevalence setting that the effects of IPTp are notable. For example, IPTp is not a part of antenatal care in the States because malaria prevalence is far too low to be considered a threat that warrants a policy of treating every woman as though she has malaria (which is what IPTp does -- it is not really a chemoprophylactic so much as it is a curative approach to malaria that is safe to use even if you don't have malaria, are pregnant, etc).
As for the 076 study... I'll have to look that up. I don't think I have heard of it.
By "strictly observational", I mean that we will not tell some women to use IPTp and others not to use IPTp. We will simply collect samples when they give birth and data about whether they received IPTp. My guess is that the study you mentioned gave effective therapies to some and withheld it from others; that is not a part of our study design.
ReplyDelete