CD4 and seasonal allergic rhinitis: The findings that the fraction of CD4+ lymphocytes was lower in winter, whereas the fractions of the CD4+ cells that were Th1 and Th2 cells were higher, are consistent with the general thinking regarding increased infectious burden and/or allergic burden in the different seasons.34 The former result is consistent with recent small studies in healthy volunteers with allergic hay fever.52 The latter findings, to our knowledge, have not been observed before.