Native American Age at Death in the USA.

There are persistent disparities in mortality rates between Native Americans and other groups in the USA. Public-use mortality data severely limits the ability of researchers to examine contextual factors that might explain these disparities. Using restricted-use mortality microdata, we examine the relationship between geographic location, specific causes of death, and age at death. We show that Native American women, on average, die 13 years earlier than White women; Native American men, on average, die 12 years earlier than White men. These disparities are largest in the northern Great Plains and Rocky Mountain states. The disparity in age at death is in part due to Native Americans dying from diseases at younger ages than White Americans. Native American women and men die younger and more often from homicide in counties with persistently higher White male to female ratios. Native American men also die younger and more often from homicide when White male to female ratios increase within their county over time. Supplementary Information: The online version contains supplementary material available at 10.1007/s41996-021-00095-0.

Investigation of bites and itching in a word processing department.

This study investigated arthropod and nonarthropod sources of reported bites and itching in a word processing division of a St. Louis, Mo., municipal department. Bird and rodent mites were suspected as causes of the bites because of the large population of pigeons around window ledges on some floors and the sighting of mice in the office. No mites or other arthropods were found to be responsible for the problem. Air samples were negative for fiber glass. Surface-vacuum samples collected around desks contained small quantities or traces of fiber glass or mineral wool. Humidity in the occupied space was considered low, about 35% relative humidity, with carbon dioxide measurements exceeding 1000 ppm. A single cause of the bites was not identified; however, a combination of surface-borne dust on desk tops and floors, the presence of minute quantities of mineral wool and fiber glass, relatively dry conditions, little or no outdoor air supplied to the work space, evidence of seasonally associated high work load, labor/management strife, and the presence of over 17 computers being used on a 24-hour basis (possibly leading to high levels of static electricity) were suspected as multiple causes of most of the "bites." After removal of loose mineral wool and dirt from an air handling unit and implementation of an aggressive cleaning routine, no more bites or itching were reported after a 6-month, 1- and 2-year follow-up period. Further research is needed to determine the relative importance of surface-borne dust and fibers, work stress, psychosocial support, and static electric fields, to produce bite-like sensations.

Evidence supporting the presence of Borrelia burgdorferi in Missouri.

Although Lyme disease is commonly seen in the southcentral United States, the epidemiology of the disease is poorly defined there. The purpose of this study was to document the presence of Borrelia burgdorferi in ticks collected in southeastern Missouri and around the city of St. Louis. Spirochetes were detected and identified as B. burgdorferi by immunofluorescent antibody (IFA) tests using the monoclonal antibody H5332 in 1.9% of Amblyomma americanum and 2.0% of Dermacentor variabilis ticks collected. The identity of IFA-positive organisms was verified by polymerase chain reactions (PCRs) with two different sets of B. burgdorferi-specific primers followed by Southern blotting. The DNA sequences of amplified 371-basepair PCR products from two positive Missouri ticks showed 97-98% identity with that obtained by the same method for the B31 strain of B. burgdorferi. These results confirm that B. burgdorferi is present in questing D. variabilis and A. americanum ticks in areas of Missouri where Lyme disease occurs. Additional studies are needed to determine the role of these ticks in the epidemiology of Lyme disease in Missouri and neighboring states.

Effect of inhibitors on acid phosphatase activity in the haemolymph of the large milkweed bug, Oncopeltus fasciatus (Hemiptera:Lygaeidae).

1. Cyanide and azide showed increases in inhibition during the latter part of the fifth stadium after juvenile hormone (Law-Williams) application. 2. Azide showed greater inhibition in the adults than in the fifth instars except for the JH-treated fifth female which showed approximately the same amount of inhibition as the adult female.