[Leukocyte count in French people living in Mali]

The authors studied the leucocytes count of 173 French people living in Mali (West Africa) during 4 years. 8.3% of these subjects presented neutropenia under 1,800/mm3, 12.2% had lymphocytosis over 4,000/mm3 and 11.6% hypereosinophilia over 500/mm3. These abnormalities differ considerably from one year to another in the same subject; their frequency does not depend upon the age, the sex, the duration of the stay in Africa. Eosinophilia is secondary to helminthiasis. Neutropenia and lymphocytosis are probably secondary to unknown evironmental factors.