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R Killick-Kendrick

Publications and source records attributed to R Killick-Kendrick.

At least 55 records · Page 3Linked to original sources
PubMed1990

Phlebotomine vectors of the leishmaniases: a review.

An account is given of work published during the past 10 years incriminating species of phlebotomine sandflies as vectors of Leishmania species which infect man. An assessment is made of the degrees of certainty of the vectorial roles of eighty-one species and subspecies of sandflies (thirty-seven Old World and forty-four New World) in the transmission of twenty-nine leishmanial parasites of mammals. At least one species of sandfly is considered to be a proven vector of each of ten parasites. Of the eighty-one sandfly taxa, evidence is judged to be sufficient to incriminate nineteen as proven vectors (eleven Phlebotomus species and eight Lutzomyia species or subspecies) and evidence for a further fourteen (nine Phlebotomus species and five Lutzomyia species or subspecies) is considered to be strong. The suggested criteria for incrimination of a vector are anthropophily and common infection with the same leishmanial parasite as that found in man in the same place. More weight should be given to natural infections persisting after the digestion of a bloodmeal than those in the presence of blood. Supporting evidence is a concordance in the distribution of the fly and the disease in man, proof that the fly feeds regularly on the reservoir host, a flourishing development of the parasite in infected flies and the experimental transmission of the parasite by the bite of the fly.

Animals↗
PubMed1989

Absence of outer caudal setae on all larval instars of Phlebotomus tobbi from the Ionian Greek islands.

Larval instars 2, 3 and 4 of Phlebotomus tobbi Adler, Theodor & Lourie from the Greek islands of Corfu and Zakynthos were found to have two caudal setae instead of the four usually present on these instars of Phlebotomus larvae. In a scanning electron microscope comparison with larvae of P. papatasi (Scopoli), a sensillum was seen in place of each outer seta of P. tobbi larvae, suggesting secondary loss of the setae. As the larvae of less than a tenth of the species and subspecies of the genus Phlebotomus have been seen and described, it cannot be assumed that those of P. tobbi are unique in having only two caudal setae. However, four caudal setae in late instars can no longer be considered as a constant character of the genus Phlebotomus. Observations on the larvae of P. tobbi also raise the question of the unknown function of the caudal setae.

Animals↗
PubMed1988

DNA hybridizations on squash-blotted sandflies to identify both Phlebotomus papatasi and infecting Leishmania major.

Epidemiological field studies on leishmaniasis have been hampered by the laborious, and often inefficient, methods used to assess the rates of infection of sandfly vectors (Diptera; Phlebotominae) by species of the causative disease organisms, protozoal parasites of the genus Leishmania (Kinetoplastida; Trypanosomatidae). We report the rapid and accurate identification of both sandfly vector (Phlebotomus (Phlebotomus) papatasi (Scopoli] and infecting Leishmania major Yakimov & Schokov by DNA hybridizations to squash-blotted sandflies. Large numbers of whole (infected) sandflies can be quickly squashed on to nylon hybridization filters and (following standard procedures) the filter-bound DNA can be hybridized sequentially to cloned, multicopy genomic sequences that are specific for species of Leishmania (kinetoplast DNA) or for the sandfly (ribosomal (r) DNA). Our sandfly probe consists of a 3.2 kb fragment of the intergenic 'non-transcribed' spacer of rDNA of P. papatasi that we have detected only in this species: it is present in all six geographically isolated populations tested (from Tunisia through to India) but cannot be detected in the morphologically similar P. (Phlebotomus) duboscqi Neveu-Lemaire, the vector of Leishmania major south of the Sahara; it also cannot be detected in Phlebotomus species of the subgenera Larroussius and Paraphlebotomus that together with P. papatasi are the dominant man-biting sandflies in north African foci of zoonotic cutaneous leishmaniasis, where (as in many arid regions of western Asia) P. papatasi is believed to be the sole vector of L. major.

Animals↗
PubMed1987

Two populations of Phlebotomus ariasi in the Cévennes focus of leishmaniasis in the south of France revealed by analysis of cuticular hydrocarbons.

Two distinct populations of Phlebotomus ariasi Tonnoir have been identified in the Cévennes focus of leishmaniasis in the south of France using gas-liquid chromatography (GLC) of cuticular hydrocarbons extracted from individual dried female flies. Results were obtained after analysis of flies collected from CDC light traps from a domestic and a sylvatic site separated by a distance of 900 m. Flies were provided for GLC analysis as six blind samples. Using cluster and discriminant analysis techniques, five of the samples were shown to form two distinct groups, while a sixth was identified as a mixture. These findings were subsequently confirmed to correspond exactly with the way the samples had been presented. Samples grouped together on the basis of the flies' cuticular hydrocarbon profiles had been taken from the same site, while the ungrouped sample had been deliberately mixed. Using a jack-knifed estimator, it is shown that specimens can be correctly allocated to the population to which they belong with a 92% success rate. These results confirm the value of the technique for the identification of populations of medical vectors. The implication of the findings for the epidemiology of leishmaniasis is discussed with special reference to the need to determine if both populations are vectors and to study differences in behaviour. In addition to adults, profiles of larval sandflies have been obtained for the first time.

Animals↗
PubMed1987

Honeydew of aphids as a source of sugar for Phlebotomus ariasi.

Wild-caught Phlebotomus ariasi Tonnoir, starved until their sugar meals had been digested, were caged for 24 h with plants or plants infested with aphids and then tested for fructose, a constituent of plant sap. No evidence was found that the flies took sap directly from nine types of plants present in their habitat. About two-thirds of flies caged with oak (Quercus ilex L.) infested with an aphid [Lachnus roboris (L.)] and about a fifth kept with leaves of the french bean (Phaseolus vulgaris L.) infested with an aphid took honeydew. Experiments with three other aphid species gave negative results. Of sandflies caught in an oak tree infested with aphids, half of the females and three-quarters of the males contained fructose. Tests on females caught in a house and grouped according to state of engorgement showed that, having taken blood, the females stop taking sugar until the bloodmeal is completely digested. It is predicted that honeydews are important in the development of Leishmania infantum Nicolle in the gut of P. ariasi.

Animals↗
PubMed1987

The life expectancy of phlebotomine sandflies: first field estimates from southern France.

1. A field study of Phlebotomus ariasi Tonnoir, the vector of Leishmania infantum Nicolle in southern France, addressed the following questions: Is it possible to estimate reliably the life expectancy of this sandfly; can spatial or temporal variation in the life expectancy be detected, and is such variation significant for disease transmission? 2. Life expectancy was estimated by examining follicular relics in the ovaries of more than ten thousand females caught in light traps at seven sites in the Cévennes and the Garrigues, throughout their active period in 1985 and 1986. Whilst the distinction between nulliparous and parous flies was easily made, assessments of the number of times a parous fly had laid eggs were unreliable. Best estimates of life expectancy were therefore calculated from the parous rate. 3. Large samples collected from one site in the Cévennes in both years gave very similar estimates of life expectancy. 4. There was also no significant difference between estimates obtained from the Cévennes and the Garrigues, despite their distinct vegetation and climates. Therefore, large regional differences in sandfly population size and the prevalence of canine leishmaniasis cannot be explained by a difference in adult survival rate. 5. With no systematic annual or regional variation, a useful mean life expectancy can be calculated from the data collected at all sites in both years. It is 1.54 (SE 0.04) ovarian cycles. However, this estimate is sensitive to the assumption that survival rate is a discrete rather than a continuous variable. 6. Local variation in the parous rate may be associated with the proximity of traps to P.ariasi emergence sites.

Age Factors↗
PubMed1987

Honeydew sugars in wild-caught Phlebotomus ariasi detected by high performance liquid chromatography (HPLC) and gas chromatography (GC).

Phlebotomus ariasi Tonnoir sandflies were caught in light traps hung in oak trees and in a house in the Cévennes focus of leishmaniasis in the South of France. The flies were cryopreserved either immediately on removal from the traps, or after starvation for 6-7 days, or after 6-7 days starvation followed by exposure to oak infested with the aphid genera Lachnus or Thelaxes. After transportation to the laboratory, the sandflies were thawed and aqueous extracts of the crushed flies were analysed for their carbohydrate content using high performance liquid chromatography (HPLC) and gas chromatography (GC). Starved female sandflies lacked significant amounts of any saccharides. Four types of sugar, melezitose and its hydrolysis products turanose, glucose and fructose, were observed in flies which had been starved previously and then placed with Lachnus infested oak. The results also indicate the presence of hydrolysis products of melezitose: (a) in flies previously starved and placed with Thelaxes infested oak, (b) in P.ariasi cryopreserved direct from the light traps hung in oak trees infested with Lachnus and Thelaxes, and (c) flies caught in a house. Unidentifiably small quantities of a trisaccharide were also detected in the latter groups of flies. In previous tests, sugars were detected in P.ariasi after their exposure to aphid-infested oak (Quercus ilex L.), but not when P.ariasi females were exposed to washed oak leaves without aphids. The results indicate that P.ariasi feed on melezitose and/or turanose, the main local source of which is aphid honeydew. A better understanding of sugar meal sources of sandflies using HPLC and GC techniques will assist in our understanding of sandfly/Leishmania relationships, parasite transmission and epidemiology.

Animals↗
PubMed1986

Observations on early and late post-sporozoite tissue stages in primate malaria. IV. Pre-erythrocytic schizonts and/or hypnozoites of Chesson and North Korean strains of Plasmodium vivax in the chimpanzee.

In a continuing reexamination of plasmodial tissue stages within the context of the hypnozoite theory of malarial relapse, 2 strains of Plasmodium vivax with distinct and disparate relapse characteristics in humans were studied in chimpanzees. Following intravenous inoculation of massive numbers of salivary gland sporozoites, both the frequently relapsing Chesson strain and a North Korean strain characterized by predominantly delayed relapses exhibited relapse patterns and antimalarial sensitivity in the splenectomized chimpanzee essentially indistinguishable from those seen in humans. Examination of hepatic biopsies obtained at 7 and 10 days after infection revealed both pre-erythrocytic (pre-e) schizonts and hypnozoites in tissue obtained from the animal infected with the Chesson strain, but only rare hypnozoites (no pre-e schizonts) at 7 days in the animal infected with the North Korean strain. These findings, combined with the comparability of relapse behavior--which indicates the suitability of the chimpanzee as a model for the natural (human) host-parasite relationship--are essentially as predicted by the hypnozoite theory, despite the small numbers of tissue forms seen. Pre-erythrocytic schizogony of the Chesson strain in the liver was essentially indistinguishable from that of other strains studied, also underlining the suitability of this model system for tissue stage studies of P. vivax.

Animals↗
PubMed1985

Leishmania infecting man and wild animals in Saudi Arabia. 1. General survey.

Using up to 13 enzymes, biochemical characterization of 75 isolates of Leishmania made from man, wild animals and sandflies from a wide variety of localities in the Kingdom of Saudi Arabia has revealed the presence of L. major (two similar zymodemes), L. tropica (two zymodemes) and a parasite of the L. donovani-L. infantum complex. Zymodeme LON-4 of L. major has been found in 52 of 53 isolates so far characterized from man, from one specimen of Phlebotomus papatasi, from 15 Psammomys obesus, from one Meriones libycus and from one dog. One isolate from man has been identified as a new variant of L. major. This variant, zymodeme LON-65, varies from zymodeme LON-4 in a single enzyme. While this is the only example of zymodeme LON-65 identified so far, zymodeme LON-4 has also been obtained from Kuwait and Iraq. These are the first reports of L. major in Meriones libycus from Saudi Arabia and the first proven isolate from the dog in any country. L. tropica was identified from only two foci, whereas L. major appears to be widely distributed in the Kingdom. Two infants with kala-azar were found to be infected with a parasite apparently identical to zymodeme LON-42 of L. donovani (sensu lato) which also occurs in the highlands of Ethiopia.

Animals↗
PubMed1985

Zoonotic cutaneous leishmaniasis in Saudi Arabia: the incrimination of Phlebotomus papatasi as the vector in the Al-Hassa oasis.

Surveys of the phlebotomine fauna in a focus of zoonotic cutaneous leishmaniasis (ZCL) in the Al-Hassa oasis, Eastern Province, Saudi Arabia, revealed only one species of Phlebotomus (P. papatasi) and three of Sergentomyia (S. antennata, S. clydei and S. fallax). 11 specimens of P. papatasi from six sites in the oasis were found with promastigotes in the midgut. An isolate from one of the sandflies was typed by the examination of isoenzymes and identified as Leishmania major, zymodeme LON-4 (= Montpellier zymodeme 26), the principal zymodeme of L. major isolated from patients with ZCL in the oasis. Three isolates from leishmanial lesions at sites of the bites of wild caught specimens of P. papatasi were also identified as the same zymodeme of L. major as the isolate from the sandfly. The findings show that P. papatasi is the vector of ZCL in the Al-Hassa oasis and probably in other ecologically similar foci in the Kingdom.

Animals↗
PubMed1985

Zoonotic cutaneous leishmaniasis in Saudi Arabia: lesions healing naturally in man followed by a second infection with the same zymodeme of Leishmania major.

A patient with a previous history of an infection with Leishmania b. braziliensis contracted zoonotic cutaneous leishmaniasis (ZCL) in the Al-Hassa oasis, Eastern Province, Saudi Arabia. Five lesions healed spontaneously over a period of 40 weeks without treatment. A year after acquiring ZCL he became infected again in the same focus. Isolates of parasites at both episodes were identified as L. major, zymodeme LON-4. Compared with the first infection of ZCL, parasites were fewer in the lesions on the second occasion, the lesions were smaller and healing was quicker (10 weeks). This work and a previous report of patients with active lesions and leishmanial scars suggest that second infections of L. major are not uncommon in the oasis where no autochthonous infections of other species of Leishmania have yet been recorded in man and only one species of Phlebotomus (P. papatasi) is known.

Adult↗