Journal of Medical Entomology 

About: Journal of Medical Entomology is an academic journal published by Oxford University Press. The journal publishes majorly in the area(s): Ixodidae & Population. It has an ISSN identifier of 0022-2585. Over the lifetime, 8468 publications have been published receiving 222857 citations.

Forensic Entomology: An Introduction

Abstract: Dorothy E. Gennard. Forensic Entomology: An IntroductionJohn Wiley and Sons, Chichester, United Kingdom, 2007224 pp., $55.00 (soft), ISBN: 978-0-470-01479-0 As forensic entomologists, we constantly hear claims that student interest in forensic science is a passing fad. However, a close inspection of past and future needs soon shows that the demand for more and better qualified forensic scientists has been strong and continues to grow. In much the same way, readers sometimes make a cursory scan of a book and dismiss it as light weight or superficial. We made that mistake with Forensic Entomology: An Introduction —we didn’t expect the book to amount to much, but the more we read, the more we found to value. As we have learned yet again, whereas you can judge a blow fly by its puparium, you can’t judge a booklouse by its exoskeleton. Forensic Entomology: An Introduction is not a reference or a manual; it is an introductory undergraduate text. Actually, it could even serve as a supplemental text in some graduate courses …

The epidemiology of tick-borne Crimean-Congo hemorrhagic fever in Asia, Europe, and Africa.

Abstract: Crimean-Congo hemorrhagic fever (CCHF) came to modern medical attention in 1944–1945, when about 200 Soviet military personnel were infected while assisting peasants in war-devastated Crimea (Ukrainian SSR). Subsequent epidemics occurred in Astrakhan (1953–1968) and Rostov Oblasts (1963–1971) of USSR and in Bulgaria (1953–1973). There have been numerous lesser outbreaks in southern USSR and, in 1976, outbreaks in Pakistan. However, it was only in 1967, when Soviet workers first used the generally accepted newborn white mouse (NWM) inoculation technique for CCHF virus isolation and study, that the etiologic agent could be characterized antigenically, physiochemically, and morphologically. Collaboration in 1968 between the Soviet and American experts M. P. Chumakov and Jordi Casals demonstrated the serologically identical properties of virus strains from human CCHF patients and corpses, lower mammals, and ticks from Asian and European areas of the USSR and from Bulgaria, Congo (Zaire), Nigeria, and Pakistan. These results, confirmed and broadened in subsequent studies, enabled serological and other research tools to be developed for producing identifiable antibodies and antigens required in experimental procedures and seroepidemiological surveys and obtaining scientific evidence to demonstrate vector and reservoir species and virus dynamics in nature. CCHF virus, a member (without generic assignment) of the family Bunyaviridae, is the prototype of the CCHF serogroup, which also includes Hazara virus (from Ixodes redikorzevi parasitizing alpine voles in Pakistan). CCHF virus is enzootic in the Palearctic, Oriental, and Ethiopian Faunal Regions, chiefly in steppe, savanna, semidesert, and foothill biotopes where 1 or 2 Hyalomma species are the predominant ticks parasitizing domestic and wild animals. Presence of the virus has been demonstrated by isolations from humans, other mammals, and/or ticks, or by seroepidemiological survey results, in western and southern India, Pakistan, Afghanistan, Iran, Soviet Middle Asia (Turkmen, Uzbek, Kazakh, Kirgiz, and Tadzhik SSR), Transcaucasia (Armenian and Azerbaijan SSR), European USSR (Ukrainian and Moldavian SSR, Kalmyk and Daghestan ASSR, Astrakhan and Rostov Oblasts, and Krasnodar and Stavropol Regions of RSFSR), Bulgaria, Yugoslavia, Greece, Hungary, France, Senegal, Nigeria, Central African Empire, Zaire, Uganda, Kenya, Ethiopia, Tanzania, and Egypt. The ecologically atypical CCHF foci in Moldavian deciduous forest habitats of Ixodes ritinus and Dermatentor and Rhipicephalus species may represent a spillover phenomenon associated with environmental changes created by humans. CCHF virus is a true tick-associated arbovirus; it survives transstadially (from larva to nymph to adult) and interseasonally in several tick species and is transmitted transovarially to the F1 generation (in some cases to F2) in Hyalomma m. marginatum, H. marginatum rufipes, Dermacentor marginatus , and Rhipicephalus rossicus . Twenty-five tick species and subspecies have been reported to be CCHF virus reservoirs/vectors (the single record from an argasid, the birdparasitizing Argas persicus, remains to be confirmed). One-host ticks, Boophilus annulatus, B. microplus, B. decoloratus (and probably B. geigyi ), appear to maintain intense virus interaction for many weeks or months between several tick species infesting artiodactyls (especially cattle). The 2-host vectors are Hyalomma m. marginatum, H. mmginatum turanicum and H. marginatum rufipes (and probably H. marginatum isaaci ); they feed as immatures on birds, hares, or hedgehogs and, as adults, chiefly on artiodactyls (often also on humans). Other 2-host vectors, H. anatolicum anatolicum, H. detritum , and Rhipicephalus bursa , feed both as immatures and adults on artiodactyls. The H. marginatum complex, and H. a. anatolicum , are especially important in causing epidemics and outbreaks of human CCHF owing to their great numbers during certain periods and to their aggressiveness in seeking human hosts. Others, including 13 species of 3-host ticks [ Haemaphysalis punctata, Amblyomma variegatum, Dermacentor (2 spp.), Hyalomma (5 spp.), and Rhipicephalus (4 spp.)], which generally seek human hosts less aggressively than the cited hyalommas, serve chiefly to maintain enzootic foci of CCHF virus circulation between ticks and wild and domestic mammals. Ground-feeding birds are often hosts of CCHF virus-infected ticks but birds apparently do not become viremic; the epidemiological role of these birds is to support populations of certain vector species and to disseminate these species intracontinentally and/or intercontinentally. CCHF epidemics have developed on a background of favorable climatic factors and environmental changes beneficial for survival of large numbers of hyalommas and of the hosts of both their immature and adult stages. The environmental changes have been wartime neglect of agricultural lands, introduction of susceptible military personnel or new settlers into infected foci, widescale collectivization of agriculture, changing pasture patterns, converting floodplains and marshy deltas to farmland and pastures, flood control, etc. Unusually severe winter-spring weather, resulting in decimation of Hyalomma populations and also of hosts of immature stages, appears to have been largely responsible for virus circulation to revert from epizootic (epidemic) to enzootic intensity. Humans become infected when bitten by infected ticks, or when crushing these ticks in their bare hands or shearing tick-infested sheep. Household and nosocomial cases resulting from contamination by bloody discharges from CCHF patients have been especially numerous and severe, often with great mortality, in villages and hospitals where the disease was unrecognized. Other cases have occurred from laboratory accidents and from handling infected animal carcasses. Mild, moderate, and severe disease courses are described. A certain number of human infections may be clinically inapparent. Mortality rates in CCHF patients have ranged from 15 to 40% or more. Despite the absence of specific drugs for treating CCHF, the Leshchinskaya regimen of hospital care has resulted in appreciable reduction in mortality rates. There are no scientific data to indicate that the virus is less virulent in Africa than in Eurasia. An apparently effective vaccine has been developed to prevent infections in persons in high-risk situations. Various measures applied to prevent human illness have had mixed success. The sensitivity of serological tests for CCHF antibodies needs to be improved to obtain more reliable survey results and to determine whether there are significant differences between CCHF virus strains. The fluorescent antibody technique (FAT) is useful for determining the presence of antibodies to the virus in vertebrate tissues and in ticks (but the dynamics of the virus in ticks has not been investigated). The indirect FAT is an important candidate for research in relation to epidemiological surveys. Most CCHF strains yield no agglutinating antigens (unlike all other arboviruses causing significant human disease, except Colorado tick fever virus); CCHF virus also replicates poorly or not at all in most cell cultures and no visible cytopathogenic effect has been described. Addendum . In 1978, while this manuscript was in press, CCHF isolates were reported from Hyalomma dromedarii in Turkmenia and Rhipicephalus appendiculatus in Uganda. Thus, 27 tick taxa have been associated with CCHF virus.

An Update on the Potential of North American Mosquitoes (Diptera: Culicidae) to Transmit West Nile Virus

Abstract: Since first discovered in the New York City area in 1999, West Nile virus (WNV) has become established over much of the continental United States and has been responsible for >10,000 cases of severe disease and 400 human fatalities, as well as thousands of fatal infections in horses. To develop appropriate surveillance and control strategies, the identification of which mosquito species are competent vectors and how various factors influence their ability to transmit this virus must be determined. Therefore, we evaluated numerous mosquito species for their ability to transmit WNV under laboratory conditions. This report contains data for several mosquito species not reported previously, as well as a summary of transmission data compiled from previously reported studies. Mosquitoes were allowed to feed on chickens infected with WNV isolated from a crow that died during the 1999 outbreak in New York City. These mosquitoes were tested approximately 2 wk later to determine infection, dissemination, and transmission rates. All Culex species tested were competent vectors in the laboratory and varied from highly efficient vectors (e.g., Culex tarsalis Coquillett) to moderately efficient ones (e.g., Culex nigripalpus Theobald). Nearly all of the Culex species tested could serve as efficient enzootic or amplifying vectors for WNV. Several container-breeding Aedes and Ochlerotatus species were highly efficient vectors under laboratory conditions, but because of their feeding preferences, would probably not be involved in the maintenance of WNV in nature. However, they would be potential bridge vectors between the avian-Culex cycle and mammalian hosts. In contrast, most of the surface pool-breeding Aedes and Ochlerotatus species tested were relatively inefficient vectors under laboratory conditions and would probably not play a significant role in transmitting WNV in nature. In determining the potential for a mosquito species to become involved in transmitting WNV, it is necessary to consider not only its laboratory vector competence but also its abundance, host-feeding preference, involvement with other viruses with similar transmission cycles, and whether WNV has been isolated from this species under natural conditions.

Vector Competence of North American Mosquitoes (Diptera: Culicidae) for West Nile Virus

Abstract: We evaluated the potential for several North American mosquito species to transmit the newly introduced West Nile (WN) virus. Mosquitoes collected in the New York City metropolitan area during the recent WN virus outbreak, at the Assateague Island Wildlife Refuge, VA, or from established colonies were allowed to feed on chickens infected with WN virus isolated from a crow that died during the 1999 outbreak. These mosquitoes were tested ≈2 wk later to determine infection, dissemination, and transmission rates. Aedes albopictus (Skuse), Aedes atropalpus (Coquillett), and Aedes japonicus (Theobald) were highly susceptible to infection, and nearly all individuals with a disseminated infection transmitted virus by bite. Culex pipiens L. and Aedes sollicitans (Walker) were moderately susceptible. In contrast, Aedes vexans (Meigen), Aedes aegypti (L.), and Aedes taeniorhynchus (Wiedemann) were relatively refractory to infection, but individual mosquitoes inoculated with WN virus did transmit virus by bite. Infected female Cx. pipiens transmitted WN virus to one of 1,618 F1 progeny, indicating the potential for vertical transmission of this virus. In addition to laboratory vector competence, host-feeding preferences, relative abundance, and season of activity also determine the role that these species could play in transmitting WN virus.

Flies as forensic indicators.

Abstract: Synanthropic flies, particularly calliphorids, are initiators of carrion decomposition and, as such, are the primary and most accurate forensic indicators of time of death. The relevant biology and forensic applications of the egg, larva, pupa, and young adult are discussed for various species, with emphasis on thermal history and age markers.