49 
Of 244 tubes of glycerinated virus examined we found an average 
6f 1,742 bacteria per tube. A number of these capillaiw tubes con- 
tained over 10,000 bacteria and one as high as 30,000. This is of 
course much more than a carefully prepared glycerinated virus should 
contain. 
We found the pus cocci and other bacteria, pathogenic for labora- 
tory animals, in both the dry points and the ghmerinated virus. 
We have demonstrated that some of the gl}"cerinated virus marketed 
during the winter of 1901-2 contained an excessive number of bacteria, 
which decreased notably after a few weeks, indicating the sale of a 
“green” or unripe product; that is to sa}^, the virus was not glycer- 
inated a sufficient length of time before it was sold. 
It was also plain from our studies that too much confidence was 
placed by the producers in the germicidal power of glycerin. 
The excessive impurities found in some of the glycerinated virus 
upon the market we believe was largely due to this overconfidence in 
the germicidal value of ghmerin; operators become careless, trusting 
to the glycerin to purify their product. WeknoAvthat glycerin is 
too feeble in its properties to purif}^ vaccine matter which has initial 
contamination such as our work indicates. 
After we called attention to this point we found a marked improve- 
ment in the glycerinated virus on the market. For instance: 
During the winter of 1901-2 the glycerinated virus contained an 
average of 4,698 bacteria per tube. 
In the spring (April and May) of 1902 the average fell to 1,058 
bacteria per tube. 
This winter (November and December), 1902, the average of 89 
tubes examined was only 29 bacteria — maximum 239. 
Glycerinated virus, when proper!}^ prepared and kept a sufficient 
length of time, is freer from impurities than dry points made with 
fresh “lymph.” 
There^ is practically no difi'erence between the gh^cerinated virus 
dried upon ivory points and that hermetically sealed in capillary tubes, 
so far as bacteriological impurities are concerned. 
It will be seen that there is practically no vaccine on the market 
free from bacterial contamination, although the product of some man- 
ufacturers is remarkably pure. 
The unevenness of the purity of vaccine as marketed by some man- 
ufacturers is very marked. The greater contamination of the vaccine 
during the winter of 1901-2 may be accounted for, in part, b}" the 
undue haste and accompanying carelessness incidental to supplying 
the increased demand for vaccine virus at that period. 
W e have examined a great number of dry points and the contents of 
gl 3 'cerinated tubes for tetanus, but have been unable to find the 
organism of this disease. 
22158— No. 12— OT 4 
