KRT1 and infection: The prevalence of multiple clonal infections with K1 and MAD20 allelic types in < 5 years age group was significantly higher than in ≥ 5 years age group (p = 0.017, two-proportions test); while the prevalence of multiple clonal infections with MAD20 and RO33 allelic types was significantly higher in the ≥ 5 years age group than in the < 5 years age group (p = 0.043, two-proportions test).