September 20, 2007

When Normal Isn't Normal

n a discovery that could mean progress for HIV/AIDS research, a group of experts in Africa have determined that “healthy” levels of various blood components differ between people in some African countries and people in North America and Europe.

Previously, many Africans who showed up to participate in AIDS vaccine trials were turned away because their white blood cell count and other blood indicators were not in the designated “normal” range. However, researchers have now discovered that the standards used to judge what is normal in the United States may be different than what is normal in some sub-Saharan African countries.

But while this means that more people may be eligible to participate in AIDS research trials, it also raises question about why some people’s normal blood levels might differ from others—and how much poor access to health care and nutrition in sub-Saharan Africa play roles in this difference.