8 
SEASONAL VARIATION IN THE PURITY OF VACCINE VIRUS. 
A glance at the following tables will show the unevenness of the 
product of some manufactures. It will be noted that the contaminat- 
ing microbes seemed to rise in numbers during the winter of 1901-2, 
when the demand for vaccine virus was very great, indicating perhaps 
haste in its production, or the marketing of an unripe product. It will 0 
also be noted that there is a marked improvement in the glycerinated ! 
product this winter (1902) as compared with that placed on the market 
last year. We believe that our warning, showing the feeble germi- 
cidal properties of glycerin, and an exposition of the fact that some '• 
of the glycerinated virus found upon the market was “green, ” helped ! 
materially toward this beneficial result. (See article in American 
Medicine, April 19, 1902, page 637, “ Dry points versus glycerinated 
virus from a bacteriologic standpoint,” read at a meeting of the New 
York Academy of Medicine, February 20, 1902, by M. J. Rosenau.) 
Tables comparing the number of bacteria in the dry points and glycerinated virus marketed : 
by the various manufacturers at different times. i 
MANUFACTURER NO. 1. 
Dry points. 
Glycerinated virus. 
Winter, 
1901-2. 
April and 
May, 1902. 
November 
and Decem- 
ber, 1902. 
Winter, 
1901-2. 
April and 
May, 1902. 
November 
and Decem- 
ber, 1902. 
4,923 
7,240 
0 
192 
22 
1 
6,240 
7,326 
0 
1,332 
24 
2 
9, 050 
7, 625 
1 
1,456 
28 
2 
9, 289 
7,625 
1 
6,249 
46 
2 
9,884 ^ 
9,430 
2 
6, 876 
72 
3 
10, 629 
aO, 050 
3 
7, 274 
101 
3 
14, 826 
10, 340 
3 
48 
4 
20, 828 
10, 345 
3 
80 
4 
12,075 
5 
5 
102 
12, 100 
11 
no 
9 
112 
194 
MANUFACTURER NO. 3. 
847 
2, 518 
7,465 
111 
3,011 
41 
906 
2, 727 
8, 702 
138 
4,309 
70 
2, 088 
3, 275 
10, 022 
246 
6,022 
87 
2, 750 
3, 866 
10, 265 
352 
6,670 
95 
6,528 
4, 359 
10, 982 
1, 121 
7,294 
112 
13, 030 
4,446 
12, 923 
1, 750 
7,427 
152 
5, 577 
15, 552 
2, 070 
9,309 
230 
8,048 
25, 574 
2,263 
11,169 
234 
8, 384 
26,411 
2, 440 
239 
19, 107 
31, 380 
