Biomedical subjects

R C Holman

Publications and source records attributed to R C Holman.

112 records · Page 7Linked to original sources

PubMedDate not supplied

The human ehrlichioses in the United States.

The emerging tick-borne zoonoses human monocytic ehrlichiosis (HME) and human granulocytic ehrlichiosis (HGE) are under reported in the United States. From 1986 through 1997, 1,223 cases (742 HME, 449 HGE, and 32 not ascribed to a specific ehrlichial agent) were reported by state health departments. HME was most commonly reported from southeastern and southcentral states, while HGE was most often reported from northeastern and upper midwestern states. The annual number of reported cases increased sharply, from 69 in 1994 to 364 in 1997, coincident with an increase in the number of states making these conditions notifiable. From 1986 through 1997, 827 probable and confirmed cases were diagnosed by serologic testing at the Centers for Disease Control and Prevention, although how many of these cases were also reported by states is not known. Improved national surveillance would provide a better assessment of the public health importance of ehrlichiosis.

Ehrlichiosis↗

PubMedDate not supplied

Rocky Mountain spotted fever in the United States, 1993-1996.

During 1993 through 1996, 2,313 cases of Rocky Mountain spotted fever (RMSF) were reported to the Centers for Disease Control and Prevention (CDC) by 42 states and the District of Columbia through the National Electronic Telecommunications System for Surveillance (NETSS). During this same interval, 1,752 case report forms (CRFs) were submitted to CDC and 1,253 (70%) of the cases were categorized as confirmed RMSF by laboratory testing. On the basis of analyses performed with NETSS data, the average annual RMSF incidence during 1993-1996 was 2.2 cases per million persons; the incidence rose from 1.8 in 1993 to 3.3 per million persons in 1996. Incidence for confirmed cases was highest among children 5-9 years of age (3.7 per million) and lowest among individuals older than 70 years of age (1.4 per million). The south Atlantic region accounted for the largest proportion of confirmed cases (52%). The case-fatality rate was highest among persons 70 years of age and older (9.0%) and lowest among adults 40-49 years of age (0.6%).

Adolescent↗

PubMedDate not supplied

Rocky Mountain spotted fever in Georgia, 1961-75: analysis of social and environmental factors affecting occurrence.

For the period of 1961 through 1975, 10 geographic and sociologic variables in each of the 159 counties of Georgia were analyzed to determine how they were correlated with the occurrence of Rocky Mountain spotted fever (RMSF). Combinations of variables were transformed into a smaller number of factors using principal-component analysis. Based upon the relative values of these factors, geographic areas of similarity were delineated by cluster analysis. It was found by use of these analyses that the counties of the State formed four similarity clusters, which we called south, central, lower north and upper north. When the incidence of RMSF was subsequently calculated for each of these regions of similarity, the regions had differing RMSF incidence; low in the south and upper north, moderate in the central, and high in the lower north. The four similarity clusters agreed closely with the incidence of RMSF when both were plotted on a map. Thus, when analyzed simultaneously, the 10 variables selected could be used to predict the occurrence of RMSF. The most important variables were those of climate and geography. Of secondary, but still major importance, were the changes over the 15-year period in variables associated with humans and their environmental alterations. Detailed examination of these factors has permitted quantitative evaluation of the simultaneous impacts of the geographic and sociologic variables on the occurrence of RMSF in Georgia. These analyses could be updated to reflect changes in the relevant variables and tested as a means of identifying new high risk areas for RMSF in the State. More generally, this method might be adapted to clarify our understanding of the relative importance of individual variables in the ecology of other diseases or environmental health problems.

Climate↗

PubMedDate not supplied

Heterosexual and mother-to-child transmission of AIDS in the hemophilia community.

Growing awareness of the potential modes of transmission of the human immunodeficiency virus (HIV) has encouraged interest in the epidemiology of infection among sexual partners and children of HIV-infected persons. The authors reviewed data on two groups, the first being those with HIV infection acquired heterosexually from a person whose hemophilia, or other chronic bleeding disorder, was treated with blood products. The second group was children with HIV infection acquired from a mother (vertical transmission) who either had been treated for a chronic bleeding disorder or had been the heterosexual partner of a person being treated. Surveillance data were examined for cases of acquired immunodeficiency syndrome (AIDS) in the United States reported to the Centers for Disease Control and Prevention, diagnosed before January 1, 1992, and for whom the only identified risk factor was being either the heterosexual partner or the child of a parent with a chronic bleeding disorder. Of the cases examined, 107 were in persons who were heterosexual partners of persons with chronic bleeding disorders. Of the 107, 98 (92 percent) were women and 87 (81 percent) were white; all were 17 years of age or older. In addition to the 107, there were 14 children, 10 (71 percent) of whom were diagnosed with AIDS in the first year of life. The rate of increase in such cases has not been as great in recent years as that observed early in the primary epidemic of AIDS among persons with hemophilia and other chronic bleeding disorders. These data underscore the risk of HIV transmission among heterosexually active couples, if one partner is seropositive, and the risk of transmission to offspring. Estimates of the prevalence of HIV infection among heterosexual women partners of HIV-infected men with hemophilia are comparable to estimates for women who had heterosexual contact with spouses infected with HIV from transfusions with cellular products. However, better data for estimates of persons at risk are needed to obtain more accurate comparisons.

Acquired Immunodeficiency Syndrome↗