VITAMIN A 283 



toxic immunity, as demonstrated by the Dick test in a group of preg- 

 nant women attending an antenatal clinic and in patients recovering 

 from scarlet fever with variable and inconclusive results. The admin- 

 istration of a vitamin A concentrate to one patient with puerperal 

 fever appeared to have a favorable efifect, but this was attributed to 

 mere coincidence. Burton and Balmain concluded that "there is no 

 prophylactic value in administering vitamin A in pregnancy to prevent 

 the development of puerperal fever; also that it is doubtful whether 

 the effects which have been described as following its administration 

 for the purpose of treatment are not a coincidence. The conclusions 

 based on experimental evidence of other workers have recorded that 

 a deficiency of vitamin A in the diet predisposes to changes in the 

 epithelial linings of mucous tracts in animals, and, therefore, allows 

 infection to occur. This does not, in our opinion, justify a belief that 

 the adequate supply of such vitamin would, in the presence of a suffi- 

 cient infective dose and the absence of immunity, prevent the occur- 

 rence of infection." Cramer (1930) concurred with these views and 

 protested against the use of "antiinfective" as a descriptive name for 

 vitamin A alone. Admitting and emphasizing that an adequate supply 

 of vitamin A is a powerful physiological prophylactic against infections 

 entering by the mucous membranes, he states that "it may possibly be 

 of therapeutic value also in the treatment of some chronic intestinal 

 toxemias and of chronic infections of the respiratory and intestinal 

 tracts, especially where these have been associated with defective nutri- 

 tion. But that has yet to be demonstrated. There is no evidence, how- 

 ever, that vitamin A can cure infections once the barrier of the mucous 

 membranes has been passed or that it can prevent or cure these infec- 

 tions which enter by the blood stream or by the subcutaneous tissues, 

 as they do, for instance, in puerperal septicemia. To call vitamin A an 

 'antiinfective' vitamin is as much a misnomer as to call it a 'growth- 

 promoting' vitamin. It seems unwise to exaggerate the extent of its 

 real action and to make claims for it which can not be realized. Dis- 

 appointment is sure to follow. This will discredit the more limited 

 though really effective action of vitamin A of maintaining the physiol- 

 ogical defenses of the mucous membranes, which are the portals of 

 entry of most infections in man." 



However, there has come from the University Hygienic Institute 

 and the State Serum Institute, Copenhagen, a preliminary report by 

 Lassen (1930) which appears to furnish evidence hitherto lacking, as 

 Cramer has pointed out, of the cure of infections entering the blood 

 stream by the subcutaneous tissues. Having shown that young rats, 



