Buruli ulcer is a necrotizing skin disease caused by Mycobacterium ulcerans and associated with exposure to aquatic habitats. To assess possible transmission of M. ulcerans by aquatic biting insects, we conducted a fi eld examination of biting water bugs (Hemiptera: Naucoridae, Belostomatidae, Nepidae) in 15 disease-endemic and 12 non-disease-endemic areas of Ghana, Africa. From collections of 22,832 invertebrates, we compared composition, abundance, and associated M. ulcerans positivity among sites. Biting hemipterans were rare and represented a small percentage (usually <2%) of invertebrate communities. No signifi cant differences were found in hemipteran abundance or pathogen positivity between disease-endemic and nondisease-endemic sites, and between abundance of biting hemipterans and M. ulcerans positivity. Therefore, although infection through insect bites is possible, little fi eld evidence supports the assumption that biting hemipterans are primary vectors of M. ulcerans. M ycobacterium ulcerans infection is an emerging skin disease often called Buruli ulcer (BU). Infection results in illness and lasting negative socioeconomic effects in rural areas of the tropics and subtropics (1). The pathologic changes, clinical signs and symptoms, and treatment have been reviewed elsewhere (2-5). In this article we evaluate fi eld evidence for the potential of aquatic invertebrates to be vectors of M. ulcerans.The exact mode of BU transmission remains unknown; however, past epidemiologic studies have associated BU with human activity near, or within, slow-fl owing or standing water bodies that have been created or disturbed by humans (2-4). Although several water-related risk factors have been recognized, none has been consistently reported, making it diffi cult to identify specifi c water-related risk activities (6-8). Most studies suggest that infection occurs through inoculation of M. ulcerans into skin lesions or insect bites (2,4,9-11). Portaels et al. (11) were the fi rst to propose that aquatic insects might serve as vectors of M. ulcerans. This hypothesis maintains that M. ulcerans is found in biofi lms of aquatic habitats and concentrated by grazing or fi lter-feeding invertebrates that are then consumed by predators known to bite humans (11). Initial evidence for this hypothesis used PCR detection of the insertion sequence IS2404 to document M. ulcerans' association with biting water bugs (Hemiptera), fi ltered concentrates of water, detritus, and aquatic plants (4,(12)(13)(14). These studies were important for understanding the possible environmental reservoirs of M. ulcerans. However, IS2404 is now understood to be not specifi c for M. ulcerans because this insertion sequence has been found in a number of other aquatic mycobacterial species, including M. marinum (15)(16)(17). When more discriminatory methods based on detection of variable number tandem repeats were used, many IS2404-positive environmental samples were reported to lack M. ulcerans (18). In light of these recent fi ndings, the relative fr...

Many Great Lakes coastal wetlands that remain today have been heavily fragmented by anthropogenic activities. The rate of fragmentation tends to increase during periods of low lake levels, especially in areas of low-gradient bathymetry where wetland area expands substantially and prompts the desire to dredge channels and groom shorelines. We sampled fish and invertebrates, using fyke nets and dipnets respectively, from wetland fragments paired with either areas where wetland vegetation was mowed or removed completely. Our concurrent studies showed that removal of vegetation by beach grooming and channel dredging created conduits for pelagic water to infiltrate the marsh and disrupt the ambient chemical/physical conditions. Alterations to both fish and macroinvertebrate communities were also evident where a significant amount of vegetation was removed. However, where only enough vegetation was removed to allow for boat access, impacts on fish communities were generally non-detectable. Mowing seemed to impact fish, but not invertebrates. Our data suggest that wetland fragmentation may have substantial and long lasting effects on wetland biota, but the magnitude of the impact is likely associated with the area of vegetation removed coupled with the potential for pelagic water to penetrate remaining fragments.

This report describes a cold case in which a cadaver of a 28-year-old female was exhumed in February 2005 from a cemetery in Battle Creek, Michigan. She had sustained a gunshot wound to the head and was found dead in her home on November 15, 1977. The body of the victim was subsequently embalmed and then buried at a depth of 1.8 m in an unsealed casket that was placed inside an unsealed cement vault. The exhumation yielded thousands of live specimens of a single species of the order Collembola or spring tails, Sinella (Coecobrya) tenebricosa (Entomobryidae). This species is considered to be a "tramp" species, cosmopolitan in the United States and Canada. Due to the ideal environmental conditions at the site, the population of this species underwent growth and development inside the casket for a number of years. Collected with the Collembola were large numbers of Acarina (mites) of the Family Glycyphagidae, and fly puparia, Conicera tibialis Schmitz (Order: Diptera, Family: Phoridae), also known as coffin flies. These invertebrates are sometimes mentioned by forensic investigators as occurring on corpses in graves, but aspects of their life history are rarely described. The species of Collembola that was found surviving and reproducing on this corpse in a casket exhumed after 28 years was the oldest reported grave site occurrence for any collembolan species based on a survey of the literature back to 1898.

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