John R. Paul

Isolation from Human Sera in Egypt of a Virus Apparently Identical to West Nile Virus.

Summary 1. Three strains of a filterable virus closely related to West Nile have been isolated from the blood of children living on the outskirts of Cairo, Egypt. 2. The 3 strains of virus appear to be immunologically identical. 3. In addition to a strong relationship and apparent identity with West Nile virus, the Egyptian virus crosses, although to a lesser degree, with both Japanese B and St. Louis encephalitis viruses. This was found by both neutralization and complement fixation tests. 4. The virus produces a marked encephalomyelitis in monkeys inoculated intracerebrally. Lesions are found throughout the spinal cord and brain including the cerebellum. 5. Chimpanzees develop a silent infection following intracutaneous infection of the virus. This is characterized by a viremia lasting 3 days followed by the appearance of both neutralizing and complement fixing antibodies. 6. The Egyptian virus was not neutralized by human gamma globulin collected in the United States, nor by 24 different hyperimmune sera, each containing antibodies to an antigenically distinct virus type. 7. Infection with this virus has been widespread in the local Egyptian population in 1950, with more than 70% of the inhabitants aged 4 years and over having both neutralizing and complement fixing antibodies.

Experimental Production of Hepatitis by Feeding Icterogenic Materials.

Summary An experiment on the transmission of infectious hepatitis has been carried out among 19 volunteers at 2 institutions. At one of the institutions 3 different samples of serum containing the icterogenic agent were inoculated intracutaneously into 5 human subjects, and the disease was produced in 3 after incubation periods of 56 to 70 (avg 64) days. At another institution other samples of serum and also specimens of feces (and urine) were fed to 9 human subjects, and the disease was produced in 5 after an incubation period of 20 to 84 (avg 37) days by both of these materials. One case of “naturally acquired” hepatitis has appeared among the institutional personnel 51 days after the beginning of the experiment and 31 days after the appearance of the first experimental case.

The Epidemiology of Rheumatic Fever

FOR some years reasons have been obvious for promoting the public health aspects of rheumatic fever, a disease which may be classed as our third most common chronic infection (after tuberculosis and syphilis). But in spite of the obvious need, there have also been reasons why relatively little public health work has been done on rheumatic fever in this country, and not the least among them is the fact that it has not been at all clear what should be done. Rheumatic fever is not a disease which is going to be brought under control easily. First of all its etiology is obscure, for in spite of the plain fact that this disease has something to do with hemolytic streptococcus infections, the real nature of rheumatic fever is still poorly understood. Second, there are few, if any, tests which are yet available for diagnosis like the tuberculin test or the Wassermann test. In their absence, the practitioner must resort largely to his wits and to his stethoscope. There is nothing specific, nothing as yet beyond the experimental stage, which can be recommended as a means of prevention. All of these things tend to make the public health officer regard rheumatic fever with some

THE SPREAD OF RHEUMATIC FEVER THROUGH FAMILIES

A number of epidemiological studies on rheumatic fever have been made, but in this disease, this field of endeavor is in its infancy as compared with other lines of approach. It has seemed to us, however, that here is another valuable weapon which may be brought to bear, not only because we would like to know more about the epidemiology of rheumatic fever, but it may tell us more about the nature of this obscure disease. Knowledge concerning the actual distribution and spread of human disease, that is, its epidemiology is obtained in two ways: by direct observation, and by statistical methods, the latter being wholly dependent upon the former. There has been no dearth of direct observations of one sort or another in rheumatic fever, but in spite of them, actual facts which lend themselves to statistical analyses along epidemiological lines are few. The difficulties seem to lie primarily in the nonspecific character of many of the clinical aspects of this disease. Some of its forms seem to be recognized with reasonable accuracy, but unfortunately no specific test has yet been devised to tell us when an individual actually has rheumatic fever, and we are thus unable to determine its true incidence or distribution. With these limitations in mind we have made an attempt to study the spread of rheumatic fever through families, as an epidemiological problem. We have chosen the family as a unit for study, (a) because it represents a small group in which an intimate investigation may be carried out; and (b), because one of the striking things about rheumatic fever is its high familial incidence, of which there is ample evidence (1) (2) (3). Cohn (4) has assembled figures obtained by different observers on this point and calls attention to the fact that in so-called rheumatic families, 8-10 per cent of exposed persons are

Experimental Attempts to transmit Phlebotomus (Sandfly, Pappataci) and Dengue Fevers to Chimpanzees.

Summary 1. Six chimpanzees inoculated with human serum believed to contain phlebotomus (sandfly, pappataci) fever virus, exhibited no clinical signs of infection. A slight febrile response in the 2 chimpanzees, whose temperatures were being recorded, could not be interpreted with certainty, and no evidence, pro or con, was adduced regarding the susceptibility of chimpanzees to this virus. 2. Nine chimpanzees inoculated with human dengue virus (Hawaii strain) also exhibited no clinical signs of infection, but evidence of inapparent infection was obtained by neutralization tests with the homologous mouse-adapted virus. None of 6 chimpanzees, whose serum was tested, had any anti-bodies for the dengue virus before inoculation and all developed them in high titre after inoculation.

Isolation of Poliomyelitic Virus from Human Stools.

Summary A virus fulfiling the clinical and pathologic criteria for its identification as poliomyelitic virus has been recovered from the stools from a child with abortive poliomyelitis on the second, fourteenth and twenty-fifth days after onset. This was accomplished twice after intracerebral and intraäbdominal monkey inoculation, and once after intraäbdominal inoculation alone.

Poliomyelitic Virus from Feces in Non-Paralytic Poliomyelitis. II. Infectivity by Various Routes.

Summary The SK. strain of poliomyelitic virus has been shown to be occasionally infectious by the intraperitoneal, intracutaneous, intratonsillar, and oral routes. The Mac. mordax species of monkey, as well as the Mac. cynomolgus, is susceptible to infection with poliomyelitic virus by the oral route.

POLIOMYELITIS: EARLY DIAGNOSIS AND EARLY MANAGEMENT OF ACUTE CASES

Excerpt The title of this paper indicates that it will be concerned with early aspects of diagnosis and therapy. But the adjectiveearlyshould be especially stressed, for, from the standpoint of the...

Experimental Fort Bragg Fever (Pretibial Fever) in Chimpanzees.

Summary Inoculation of Fort Bragg fever virus into chimpanzees resulted in a mild infection. This appeared to be characterized by a short febrile period with viremia and by the appearance of neutralizing antibodies in the serum a few weeks after the infection.

Serological Epidemiology and the Function of Serum Banks.

Techniques and principles which are used in serological epidemiologic investigations are described, and it has been pointed out that the World Health Organization has recently established “Serum Reference Banks” to expand the potentialities in this field.Techniques and principles which are used in serological epidemiologic investigations are described, and it has been pointed out that the World Health Organization has recently established “Serum Reference Banks” to expand the potentialities in this field. Serologic and hematologic surveys of diverse populations living in different environments have been studied recently and have yielded information regarding the fields of the epidemiology of infectious and non-infectious diseases, anthropology, and genetics. Examples of the application of serologic epidemiology to surveys of populations in several parts of the world are given.