Serum IgG, IgA and IgM Levels in Rural Namibian Infants

Serum IgG, IgA and IgM levels were measured in 300 Baster infants and 117 Nama infants living in the Rehoboth Gebiet of Namibia. The serum immunoglobulin levels were much higher than those of infants living in developed countries. This agrees with findings in infants or children of other developing communities. Differences in the mean levels of IgA and IgM appeared to be related to age, sex and ethnicity. These differences, even though of statistical significance, are not large enough to influence the practising physician in his interpretation of laboratory results in Namibian infants. The mean, standard deviation and ranges of immunoglobulin IgG, IgA and IgM levels of Baster and Nama infants may be used as reference values for infants living in the Rehoboth Gebiet. It was not possible to relate the immunoglobulin findings and their accelerated production compared to those of infants in North America and Scandinavia with any of the variables studied including, age, sex, ethnicity, feeding pattern, habitat, environment or serum methaemoglobin and ascorbic acid levels. These and other factors presumably all interact in some way on an immunological system which is genetically coded to provide the foetus, neonate, infant and child with support for healthy survival under adverse environmental conditions.