African-American troops

Andrew K. Black, In the Service of the United States Comparative Mortality Among African-American and White Troops in the Union Army, Journal of Negro History 19 1994) 331. 

Andrew K. Black has indicated that incidents of malaria among black were considerably lower than among whites due to the fact that nearly all had previous exposure to malaria and had acquired either natural immunity or exhibited attenuated symptoms. See Andrew K. Black, In the Service of the United States Comparative Mortality Among African-American and White Troops in the Union Army, Journal of Negro History 79 (1994) 324-325. 

The conclusion of the studies carried out in India, that Indian troops were less sensitive than Caucasians, is similar to conclusions from early US studies that African Americans were less sensitive than Caucasians. ... 

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