The animals are kept in quarantine on Plum Island 
long enough to insure that no disease is in the incuba- 
tion period before they are taken into the Laboratory. 
While in quarantine, they are treated to eliminate 
external parasites, such as ticks and lice. 
Animals are introduced into the research buildings 
through double-doored air locks. (The inside door is 
closed before the outside door is opened to permit 
entry.) Animals that enter the research buildings 
never come out, and none that land on Plum Island are 
ever permitted to leave the island. No virus studies 
are conducted except in the enclosed laboratory build- 
ings, and there no contact is possible with other live- 
stock or with birds and insects. 
4. Controlled introduction of all materials.—All 
equipment, supplies, feed, and other materials arriving 
at the island are received under rigid controls. Trans- 
actions, particularly at the Plum Island dock-area plat- 
form, are so regulated that persons making delivery 
do not contact or receive aid from those accepting 
delivery. The transfer platform is thoroughly cleaned 
and disinfected between such transactions. Equipment 
and supplies moving into the research buildings must 
pass over similar transfer platforms and must pass 
through autoclaves and the same type of double- 
doored air locks that are used to introduce animals. 
Feeds are processed to kill insects, rodents, and other 
vermin before being taken into the research buildings. 
In the principal research building, feed is introduced 
from an outside opening where it is dropped through 
trap doors to the basement below. Here it is hammer 
milled and then blown into feed hoppers on the second 
floor area. From these hoppers, it is taken through a 
feed corridor to chutes directly over the mangers in 
Tissue-culture flasks and test tubes are inoculated with 
foot-and-mouth disease virus. Quart-sized flasks are 
used for production of virus needed in the laboratory 
research. 
each of the animal rooms. There is a double gate 
system on each feed chute, and one gate is closed at all 
times. This feed corridor on the second floor is entirely 
independent of the rest of the building. 
5. Written permit required for entry—Only author- 
ized persons are permitted on Plum Island. All persons 
must have an approved pass and must be prepared to 
show it to any guard or safety representative upon 
request while they are on the island. They are required 
to read the printed safety regulations and to sign a 
certified statement that they will comply with them. 
Laboratory employees may be discharged for violation 
of these regulations. 
6. Protection of large compound and double fence.— 
Upon approaching the Laboratory buildings, Labora- 
tory personnel pass a guard and proceed through gates 
of a double fence. The inner fence, about 20 feet from 
the outer fence, is set in concrete extending 3 feet 
underground to prevent burrowing animals from dig- 
ging their way inside. Between the fence and the 
research building is a large open compound; it is with- 
out vegetation so as to discourage birds, rodents, and 
other animals. 
7. Regulated movement of persons entering the 
research buildings——A person entering a_ research 
building must leave street clothing and personal belong- 
ings—even jewelry and eyeglasses—in an outer locker 
room and put on laboratory clothing. He may then 
pass through a one-way turnstile to his assigned 
work area. 
If he enters such areas as the animal isolation or 
laboratory areas, he must leave the laboratory clothing 
behind and change into different laboratory clothing. 
When he comes out of the animal isolation or laboratory 
Eroded areas on the gums of this steer are typical lesions 
The animal was experi- 
of foot-and-mouth disease. 
mentally infected as part of the laboratory research. 
