225 
SOREHEAD AND ITS CONTROL 
IN HAWAII 
By H. F. Fisher 
Contagious epithelioma, commonly known as chicken-pox 
or sorehead, has been one of the chief factors that has caused 
failure in poultry in Hawaii. Climatic conditions on the isl- 
ands are semi-tropical, and as such, sorehead makes its ap- 
pearance in chickens of all ages. 
Different remedies have been advised repeatedly — some 
good, others not so good — but all required individual treat- 
ment, and that over a long period. Recovery was not always 
certain. 
In 1916 the late Dr. Norgaard, former Territorial Veteri- 
narian, made experiments at this ranch to control chicken-pox. 
A vaccine was used, prepared after the method employed by 
Dr. Beach of the University of California. The result was 
excellent. This method required two injections of vaccine 
five days apart. This was a great improvement over any 
other method used heretofore as a labor saver. 
From a commercial standpoint the great objective is to 
have a vaccine that will do the work with one inoculation, and 
to be able to use it on chickens from seven to eight weeks of 
age, whether infected or not. At this age chicks are usually 
transferred from the brooder house to colony houses. 
One can well imagine what a labor saver this method would 
be, as all chicks could be vaccinated as they were taken out 
of the crates. 
Experiments that were conducted the latter part of the sea- 
son of 1922 were made with the above mentioned objective. 
Since 1916 the loss of chickens through sorehead at this ranch 
has not been over three per cent, and as low as one per cent. 
Chicken-pox or sorehead first appears as a small blister-like 
nodule. As these increase in size, they become yellow, finally 
changing in shape and color to resemble a wart. If this growth 
or tumor is removed the surface will be raw, showing many 
small indentations. Later the surface may ulcerate and spread 
until a sore of half an inch in diameter is observed. "^he 
disease usually makes its appearance on the comb, wattles 
and skin of the head. 
Experiments from June, 1922, to September, 4, 1922 : Method 
— Hypodermic injections, subcutaneously. Point of injec- 
tion to be disinfected with iodine. Care should be taken 
while injecting the needle under the skin not to penetrate the 
flesh. Experience has proven that this is usually fatal. On 
June 1, 1922, Dr. Leonard N. Case, Territorial Veterinarian, 
sent the writer a vaccine that had been prepared by him in 
a different manner from others sent out before this. In re- 
