Field Evidence Against Rodent Burrow Entering by \u3ci\u3eAedes Triseriatus\u3c/i\u3e (Diptera: Culicidae)

(excerpt) The tree-hole developing mosquito Aedes triseriatus (Say) is the major vector of La Crosse encephalitis virus in the upper mid-western United States (Calisher and Thompson 1983). This virus overwinters in the eggs of this mosquito, and in the summer infects chipmunks and squirrels which have been bitten by infected mosquitoes (op. cit). Non-infected mosquitoes may become infected when they blood-feed on viremic sciurid rodents (Pantuwatana et al. 1972)

Seasonal Abundance and Species Diversity of Adult Tabanidae (Diptera) at Lake Lansing Park-North, Michigan

A two year study was undertaken to determine the seasonal abundance and diversity of adult deer flies and horse flies, to compare two methods of sampling (Malaise trap and sweep net), and to estimate attack rates by tabanids on people at Lake Lansing Park-North, Ingham County, Michigan, in 1990 and 1991. Tabanids were sampled using dry ice-baited Malaise traps, and by making over- head sweeps with a standard insect net while hiking a trail. Hybomitra spp. (299 individuals of 9 species) peaked in abundance in mid-May to early June in both years. Chrysops spp. (11,675 individuals of 14 species) and Tabanus spp. (324 individuals of 8 species) peaked in early-to late-July in both study years. Peak abundance for Chrysops and Tabanus spp. occurred earlier in 1991 than 1990, probably because the spring of 1991 was warmer. There were six new species records for County. More individual Hybomitra and Tabanus were taken by M traps (77.3% for Hybomitra; 76.2% for Tabanus) than by netting (22.7% for Hybomitra; 23.8% for Tabanus). In contrast, sweep netting yielded more individual Chrysops (98.3%) than Malaise traps (1.7%). Tabanid attack rates on people hiking the trail exceeded 1,000 per hour on one occasion each year, at mid-season

Straw Itch Mite, \u3ci\u3ePyemotes Tritici\u3c/i\u3e, Infestation in Brome Seed Related to Acute Dermatitis in Michigan Granary Workers

An infestation of Pyemotes tritici, the straw itch mite, apparently caused dermatitis on the arms and trunks of four workers in south-central Michigan who had unloaded a shipment of brome seed bags. Sampling of bag surfaces and contents indicated that mites occurred inside and on the surface of brome seed bags, but not in bags of other seed present at the site. One bag of fescue in contact with brome seed bags had mites on its surface. Pyemotes tritici densities on the brome seed bags ranged from 0.7 -5.6 per cm , while infestations in brome seed ranged from 0.08-0.33 mites per ml of seed. An insect repellent containing DEET was effective in preventing mite bites

\u3ci\u3eIxodes Dentatus\u3c/i\u3e (Acari: Ixodidae) in Michigan: First State Records and Occurrence on a Human

An Ixodes dentatus adult female was taken from a cottontail rabbit in Kalamazoo County, and a nymph from a child in Berrien County, in 1992 in Michigan. These findings represent the first records of I.dentatus in the state, and document an unusual parasitization of a human being by this species of tick

Replacing Members with Managers? Mutualism among Membership and Nonmembership Advocacy Organizations in the United States

Associations with a professional staff but no members (nonmembership advocacy organizations, or NMAOs) are the subject of lively debate. Many argue that their proliferation has allowed an expansion of advocacy without an accompanying growth in civic engagement. This article asks if there has been significant recent growth of NMAOs and if those organizations have displaced membership advocacy organizations (MAOs). The authors find no evidence for a proportional increase of NMAOs since the 1960s. Further, among all organizations in three populationspeace, women's issues, and human rightsNMAOs have not displaced MAOs. In particular, the authors find that MAO density shapes NMAO founding, as membership groups provide a base for professional advocacy. These findings challenge the notion that U.S. civic life has undergone a systemic transformation away from organizational forms that promote civic engagement

Magellan/M2FS Spectroscopy of Galaxy Clusters: Stellar Population Model and Application to Abell 267

We report the results of a pilot program to use the Magellan/M2FS spectrograph to survey the galactic populations and internal kinematics of galaxy clusters. For this initial study, we present spectroscopic measurements for $223$ quiescent galaxies observed along the line of sight to the galaxy cluster Abell 267 ($z\sim0.23$). We develop a Bayesian method for modeling the integrated light from each galaxy as a simple stellar population, with free parameters that specify redshift ($v_\mathrm{los}/c$) and characteristic age, metallicity ($\mathrm{[Fe/H]}$), alpha-abundance ($[\alpha/\mathrm{Fe}]$), and internal velocity dispersion ($\sigma_\mathrm{int}$) for individual galaxies. Parameter estimates derived from our 1.5-hour observation of A267 have median random errors of $\sigma_{v_\mathrm{los}}=20\ \mathrm{km\ s^{-1}}$, $\sigma_{\mathrm{Age}}=1.2\ \mathrm{Gyr}$, $\sigma_{\mathrm{[Fe/H]}}=0.11\ \mathrm{dex}$,$\sigma_{[\alpha/\mathrm{Fe}]}=0.07\ \mathrm{dex}$, and$\sigma_{\sigma_\mathrm{int}}=20\ \mathrm{km\ s^{-1}}$. In a companion paper, we use these results to model the structure and internal kinematics of A267.Comment: 16 pages, 11 figures, accepted for publication in The Astronomical Journa

Daily temperature profiles in and around Western Kenyan larval habitats of Anopheles gambiae as related to egg mortality

BACKGROUND: Anopheles gambiae eggs are more frequently found on soil around puddle habitats of the larvae, than on the water surface itself in Western Kenya. Thus, eggs can experience temperatures more wide-ranging and lethal than those experienced by larvae or pupae confined within puddles. METHODS: Small batches of eggs from house-collected An. gambiae as well as from the Kisumu laboratory strain were bathed for defined times in water whose temperature was precisely controlled. Daily temperature profiles were recorded by an infrared thermometer on seven different days in and around three types of typical An. gambiae larval habitats at Kisian. RESULTS: For wild eggs, significant mortality occurred upon brief heating between 42 – 44°C. Few eggs hatched after 10 min at 45°C and none hatched above this temperature. A similar pattern occurred for eggs of the Kisumu strain, except it was shifted downwards by 1°C. Egg mortality was time-dependent above 40°C. Temperatures of water in the three types of larval habitats never exceeded 35°C. Wet or damp mud rarely and only briefly exceeded 40°C; thus, water and mud would be highly conducive to egg survival and development. However, dry soils frequently reached 40 – 50°C for several h. Eggs stranded on dry surfaces would experience substantial mortality on hot, sunny days. CONCLUSION: Moist mud around puddles constitutes suitable habitat for An. gambiae eggs; however, eggs on the surface of dry soil under direct sunlight are unlikely to survive for more than a few hours

Association of West Nile virus illness and urban landscapes in Chicago and Detroit

BACKGROUND: West Nile virus infection in humans in urban areas of the Midwestern United States has exhibited strong spatial clustering during epidemic years. We derived urban landscape classes from the physical and socio-economic factors hypothesized to be associated with West Nile Virus (WNV) transmission and compared those to human cases of illness in 2002 in Chicago and Detroit. The objectives were to improve understanding of human exposure to virus-infected mosquitoes in the urban context, and to assess the degree to which environmental factors found to be important in Chicago were also found in Detroit. RESULTS: Five urban classes that partitioned the urban space were developed for each city region. The classes had many similarities in the two settings. In both regions, the WNV case rate was considerably higher in the urban class associated with the Inner Suburbs, where 1940–1960 era housing dominates, vegetation cover is moderate, and population density is moderate. The land cover mapping approach played an important role in the successful and consistent classification of the urban areas. CONCLUSION: The analysis demonstrates how urban form and past land use decisions can influence transmission of a vector-borne virus. In addition, the results are helpful to develop hypotheses regarding urban landscape features and WNV transmission, they provide a structured method to stratify the urban areas to locate representative field study sites specifically for WNV, and this analysis contributes to the question of how the urban environment affects human health

Vaccine-preventable haemophilus influenza type B disease burden and cost-effectiveness of infant vaccination in Indonesia.

BACKGROUND: Most of Asia, including Indonesia, does not use Haemophilus influenzae type b (Hib) conjugate vaccines. We estimated total vaccine-preventable disease burden and the cost-effectiveness of Hib conjugate vaccine in Indonesia. METHODS: Hib pneumonia and meningitis incidences for children with access to health care were derived from a randomized vaccine probe study on Lombok Island, Indonesia during 1998-2002. Incidences were adjusted for limited access to care. Health system and patient out-of-pocket treatment cost data were collected concurrent with the probe study. For Hib vaccine in monovalent and combined (with DTP-HepB) presentations, we used 2007 UNICEF vaccine prices of US$3.30 and$3.75 per dose. RESULTS: For the 2007 Indonesian birth cohort, Hib vaccine would prevent meningitis in 1 of every 179 children, pneumonia in 1 of every 18 children, and 4.9% of mortality among those younger than 5 years. The total incremental societal costs of introducing Hib vaccine in monovalent and pentavalent presentations were, respectively, US$11.74 and$8.93 per child vaccinated. Annual discounted treatment costs averted amounted to 20% of pentavalent vaccine costs. For the pentavalent vaccine, the incremental costs per discounted death and disability adjusted life-year averted amounted to US$3102 and$74, respectively, versus $4438 and$102 for monovalent vaccine. CONCLUSIONS: Routine infant Hib vaccination would prevent a large burden of pediatric illness and death in Indonesia. Even without external funding support, Hib vaccine will be a highly cost-effective intervention in either a monovalent or pentavalent presentation based on commonly used benchmarks