All EniciUa abortus strain 19 vaccine pro- 

 duced in the United States for use in State- 

 Federal brucellosis eradication is examined at 

 Heltsville before release. Vaccines that do not 

 meet the rigid requirements for purity, hy- 

 drogen ion concentration (pH), total cell con- 

 centration, viability, and colonial characteris- 

 tics are rejected. During the year, 1,516 serial 

 lots, i-epresenting 8,604,946 do.ses, were tested. 

 Of this amount, more than 7,949,876 doses 

 (92.4 percent) were released as safe and reli- 

 able for use. There has been a gradual in- 

 crease in volume production of desiccated 

 strain 19 vaccine (lyophilized) since the re- 

 lease of this i)roduct in 1945. Eighty-six per- 

 cent of the 43,024,733 milliliters produced in 

 1960 were desiccated vaccines. 



Brucella abortus Strain 19 



VACCINE RELEASED FOLLOWING TEST 



Ml I. DOSES 



1950 



1953 



1959 



US oeParthcmto^aomiculTure 



■ SHICULtUtttL HtSCKCH SCKVlCC 



In addition to the Brucella strain 19 vaccine 

 (liquid) produced at Beltsville for reference 

 purposes, 840 doses were distributed for vac- 

 cinating calves in 19 Federal in.stitution herds. 



On numerous occasions, cultures of the or- 

 ganism causing brucellosis have been supplied 

 to private and Government laboratories in the 

 United States and in many foi'eign count I'ies. 



To replace stock cultures for use in produc- 

 ing the vaccine, continuous since the jjrocedure 

 was inaugurated in 1940, 107 selected Brucella 

 abortus strain 19 cultures were supplied to 17 

 commercial laboratories and 2 State in.stitu- 

 tions during 1960, and 106 selected cultures 

 were sent to 17 foreign countries. Of the 213 

 cultures di.'^tributed, 50 percent were furnished 

 for distribution outside the continental United 

 States. 



Thirty-six selected cultures of Brucella 

 abortus antigen strain 1119-3 were distributed 

 to 1 States and 10 foreign countries for use 

 in producing antigens and for research pur- 

 poses. Stock cultures of Brucella abortus 

 .strains 19 and 1119-3 (lyophilized) are main- 

 tained at the Division laboratories at Beltsville 

 for immediate distribution to approved insti- 

 tutions throughout the world. 



The Division al.so extends technical assist- 

 ance and training to scientists from many 

 foreign lands interested in the brucellosis erad- 

 ication program of the United States. As a 

 result of those exchanges, a close working re- 

 lationship has been e.stabli.shed with .scientists 

 in many parts of the world. 



Through arrangements with the Interna- 

 tional Cooperation Administration and other 

 agencies, 26 individuals rei)re.senting 16 

 foreign countries and the Pan American Sani- 

 tai\- Bureau were approved for visits to the 

 Beltsville Laboratories in 1959. The various 

 l)ha.ses of production, .standardization, and 

 control of Brucella antigens and vaccine and 

 the diagnosis of brucellosis in animals were 

 demonstrated and discussed. 



During the year, 1,716,460 milliliters of 

 mammalian contract tuberculins i)roduced com- 

 mercially for the Agricultural Ke.search Serv- 

 ice were tested and released as satisfactory for 

 use in the State-Federal program for diag- 

 nosis of tuberculosis. 



Vesicular Diseases. — Serological testing is 

 another important function of Laboratory 

 Services at Beltsville. Of special importance 

 is the diagnosis of vesicular exanthema, in- 

 fectious bovine rhinotracheitis, and vesicular 

 .stomatiti.s, and their differentiation from foot- 

 and-mouth disease. 



Vesicular stomatitis of the New Jersey type 

 was the only vesicular disease diagnosed in 

 1959 from 36 tissue and 257 sei'um samples 

 received. The first cases again were reported 

 during May from the enzootic coastal i)lain 

 areas of North Carolina, South Carolina, 

 Georgia and Louisiana. Simultaneously, ve- 

 sicular stomatitis appeared in six counties 

 bordering the Texas side of the Rio Grande 

 River. The Texas outbreak was part of an 

 epidemic that progressed northward through 

 Mexico, crossed the Rio Grande into Texas, 

 and finally abated. 



39 



