Viruses 405 



pending epidemics, and such precautions have been shown to stop 

 the further spread of the disease. The threat of a smallpox epi- 

 demic in New York City in 1942 was promptly controlled by mass 

 inoculation. Smallpox is no longer a common disease in countries 

 like the United States where compulsory vaccination is required 

 before children can enter public schools. The pock-marked faces 

 so prevalent among people just a few decades ago are now be- 

 coming a rarity, thanks to the effectiveness of smallpox vaccination. 



Measles 



Measles, or rubeola, is essentially a respiratory disease, even 

 though the skin lesions are typical diagnostic symptoms. This in- 

 fection is caused by one of the smaller viruses for which no active 

 immunizing agent is available at the present time. By employing 

 immune serum or globulin fractions obtained from the blood of 

 adult persons, however, an effective passive transfer of antibodies 

 can be effected to help prevent measles in children under the age 

 of three. These youngsters are more prone to secondary bacterial 

 complications which lead to permanent damage to organs, and 

 even death, and measles can usually be prevented by the prompt 

 injection of globulin fractions immediately after the child has been 

 exposed to an active case of the disease. Children over the age of 

 three years should be allowed to go for from six to ten days after 

 exposure before immune serum or globulin is administered. In 

 this way the disease will be contracted, but the svmptoms will be 

 modified by the immune bodies, and the children will build up an 

 active immunit)^ to protect themselves from subsequent attacks by 

 this virus. 



German measles, called rubella, is milder than "regular" 

 measles, but this disease appears to be particularlv serious in cases 

 of pregnant women, especiallv during the earlv stages of preg- 

 nancy. There are strong indications that the virus of German 

 measles has a particular affinity for the developing fetus, and 

 serious deformities have been reported in such babies if they are 

 not aborted before termination of the full nine-month gestaticni 

 period. 



