No evidence was found to support the idea that vaccine virus placed in the cisterna magna is capable of producing an acute disseminated encephalomyelitis with perivascular demyelination either in normal or in partially immune monkeys. A testicular extract (Reynals' factor) did not induce vaccine virus to cause an acute disseminated encephalomyelitis in… (More)
The repeated intramuscular injections of aqueous emulsions and alcohol-ether extracts of sterile normal rabbit brains in some manner produced pathological changes accompanied by myelin destruction in the brains of 7 of 8 monkeys (Macacus rhesus). Eight, control monkeys remained well. Cultures from the involved brains remained sterile, and no transmissible… (More)
Rabbits injected with fresh emulsions of homologous brain developed few or no antibodies capable of fixing complement in the presence of aqueous emulsions or alcoholic extracts of rabbit brain. Complement-fixing antibodies, however, were produced in rabbits by means of injections (1) of sterile emulsions of homologous brain which had been allowed to stand… (More)
Virus III and vaccine virus multiply in a transplantable rabbit tumor of epithelial origin; are carried along with the tumor through an indefinite number of transplants; and despite an immunity developed by the rabbit host survive longer in the tumor than when injected into the testicles of normal rabbits.
Colon bacilli, Virus III, vaccine virus, herpes virus, bacteriophage, complement, and trypsin are either killed or inactivated by repeated freezing (-185 degrees C.) and thawing. As might be expected, some of the agents are more resistant than others. Hence it may be concluded that destruction or inactivation of an active agent by repeated freezing (-185… (More)
1. The intradermal method of inoculating Virus III, a hitherto unknown filterable virus producing lesions in rabbits, gives more reliable results than those obtained by smearing the virus on the scarified skin. 2. Virus III, heated 10 minutes at 55 degrees C., will not produce visible reactions in the skin of rabbits. 3. Virus III passes through Berkefeld N… (More)
The pathological changes produced by the virus under investigation are similar to those deemed characteristic of a certain well known group of filterable viruses.
1. A dermal strain of vaccine virus has been adapted to a simple culture medium consisting of minced chick embryo suspended in Tyrode's solution. 2. The bacteria-free culture virus, thus obtained, produces in lower animals and in man typical vaccinia that renders them refractory to infection with ordinary vaccine virus harvested from calves.
A l t h o u g h Rift Valley fever is a natural disease of sheep with a mortality of 50-95 per cent, it occurs also in m a n as an acute febrile illness, usually of such a mild character t h a t in over 200 cases k n o w n to have occurred in British E a s t Africa no u n t o w a r d sequelae were observed (1). T h e purpose of the present c o m m u n i c a… (More)
Monkeys that have recovered from psittacosis pneumonia have an increased resistance to infection with the virus and possess neutralizing antibodies in their sera. Large amounts of active psittacosis virus can be introduced intravenously and intramuscularly into monkeys without the production of a serious infection such as pneumonia. Relatively small amounts… (More)