41 research outputs found
Serološka i entomološka istraživanja lišmanioze u pasa u Hrvatskoj.
In Croatia, canine leishmaniosis has been recognized in the southern littoral area (Dalmatia) as a reemerging disease since 1997. This paper reports the fi ndings of a survey carried out 2.5 years after the suspension of control measures for canine leishmaniosis. Entomological and cross-sectional serological surveys were carried out in the Kaštela municipality in the Split-Dalmatia County (where stable foci of canine leishmaniosis were reported previously), and in a few localities from the Šibenik-Knin county where a few unstable foci were previously reported. Serological surveys detected a focus with 31% seropositive dogs in Rudine (the known enzootic area); a tendency for a new stable focus appearance in the Šibenik-Knin County (Rogoznica), with cumulative seropositivity of 13.5% in both areas. Entomological studies evidenced two competent Leishmania vectors, Phlebotomus neglectus and P. tobbi; the fi rst was prevalent (75.9%) being also the species much more associated to habitats where dogs are present. Moreover, prevalence for P. neglectus females feeding on human blood reached 30%.Na jugu hrvatskoga priobalja (Dalmacija) lišmanioza pasa u ponovnom je porastu od 1997. godine. U ovom radu izneseni su rezultati istraživanja provedenih 2,5 godine nakon ukidanja obveznih mjera suzbijanja lišmanioze pasa. Serološko i entomološko istraživanje provedeno je na području općine Kaštela u Splitsko-dalmatinskoj županiji (područje s poznatim stalnim žarištima pasje lišmanioze) i na nekoliko lokacija Šibensko-kninske županije gdje je zabilježeno samo povremeno javljanje lišmanioze. Serološkim je istraživanjima otkriveno žarište s 31% serološki pozitivnih pasa u Rudinama (enzootsko područje) s tendencijom nastanka novoga stalnog žarišta u Šibensko-kninskoj županiji (Rogoznica), a ukupno je bilo 13,5% serološki pozitivnih pasa. Entomološkim istraživanjima dokazana je prisutnost dviju vrsta prijenosnika koji podržavaju razvoj roda Leishmania, Phlebotomus neglectus i P. tobbi; prvi je mnogo zastupljeniji (75,9%) i češće prisutan tamo gdje ima pasa, a čak 30% pretraženih ženki P. neglectus hranilo se na ljudima
Identification of sex determination genes and their evolution in Phlebotominae sand flies (Diptera, Nematocera)
Phlebotomine sand flies (Diptera, Nematocera) are important vectors of several pathogens, including Leishmania parasites, causing serious diseases of humans and dogs. Despite their importance as disease vectors, most aspects of sand fly biology remain unknown including the molecular basis of their reproduction and sex determination, aspects also relevant for the development of novel vector control strategies
Canine leishmaniosis in the Italian northeastern Alps: A survey to assess serological prevalence in dogs and distribution of phlebotomine sand flies in the Autonomous Province of Bolzano - South Tyrol, Italy
Abstract The Autonomous Province of Bolzano-South Tyrol (APB), located in the northernmost territory of the Italian eastern Alps, is still considered non-endemic for canine leishmaniosis (CanL) despite clinical cases being observed and a competent Leishmania infantum vector (Phlebotomus perniciosus) having been recorded since 2008. A serological survey of leishmaniosis among a randomly-selected subpopulation of registered owned dogs was carried in 2018, followed by entomological investigations performed in 2019 and driven by canine survey results. A total of 457 resident dogs from all over the APB territory were examined through IFAT for antibodies against L.infantum, of which 63 (13.8%) tested positive. Thirty-five seropositive cases (7.7%) were considered autochthonous to APB, i.e. dogs born and lived in the province, or imported dogs with no travel history in the past 5 years. Most of these animals showed an antibody titre at the threshold level of 1:40, suggesting a low degree of parasite transmission/contacts. In 2 autochthonous cases with moderately high IFAT titre, the infection was confirmed by nested-PCR in peripheral blood. Thirty-one georeferenced sites were monitored for sand flies by means of interception (sticky papers) and attraction (CDC miniature light traps) collection devices. Traps were set during summer approximately on monthly basis, and extended up to October for positive sites. Only 2 sites were found positive for a total of 317 phlebotomine specimens collected by sticky traps, which included a previously known P. perniciosus-endemic site near Bolzano town. Sergentomyia minuta was by far the most prevalent (98.1%) and the only recorded sand fly species in the most northerly Italian site ever investigated (Coldrano municipality in Venosta valley). For the first time, Leishmania serology and n-PCR positive dogs autochthonous to APB were identified, however the spread of sand flies competent for L. infantum transmission could not be demonstrated in several places where endemic seropositive cases were recorded. APB can be considered a territory of low CanL endemicity, however awareness and continuous monitoring are needed to detect changes in the epidemiological status of the zoonosis
Examining the Relationship of Clinical and Laboratory Parameters With Infectiousness to Phlebotomus perniciosus and Its Potential Infectivity in Dogs With Overt Clinical Leishmaniasis
Infected dogs are considered the main domestic animal reservoirs for Leishmania
infantum parasite. Infectiousness to competent phlebotomine vectors has been
associated with many factors, the main being the severity of the disease exhibited by
infected dogs. This study examines the relationship between different clinical parameters
and the infectiousness to colonized Phlebotomus perniciosus sand flies having a blood
meal on dogs. Data obtained in the present study come from an untreated group
of Leishmania sick dogs submitted to xenodiagnosis for the evaluation of a spot on
insecticide solution. Seventeen dogs were diagnosed as affected by leishmaniasis
through clinical examination, immunofluorescence antibody test (IFAT) serology, and
loop-mediated isothermal amplification (LAMP). The disease severity (clinical score)
was staged by using a numeric value derived from eight clinical and parasitological
parameters. Xenodiagnosis was performed on caged dogs exposed for 1.5 h to sand-fly
bites. The following parameters related to sand flies were examined: blood feeding
(% of blood engorged females), promastigote detection (% of promastigote-positive
sand flies), promastigote burden, and the promastigote stage maturation (potential
transmissibility rate). Statistical relationship between the clinical score and entomological
parameters was investigated, as well as the possible correlation between each clinical
and laboratory parameters and sand fly infection/infectivity. The severity of clinical score
may influence the blood feeding by, and the probability of promastigote detection in,
sand flies; skin lesions seem to be the main factor that influences the rate of blood
feeding. Promastigote burden is related to IFAT titer, skin lesions, and clinical score. All
entomological parameters are strongly related among them. This study confirms that
both P. perniciosus infection and infectivity are influenced by a dog’s clinical condition
The spatial clustering of X-ray selected AGN in the XMM-COSMOS field
We study the spatial clustering of 538 X-ray selected AGN in the 2 deg^2
XMM-COSMOS field that are spectroscopically identified to I_{AB}<23 and span
the redshift range z=0.2-3.0. The median redshift and luminosity of the sample
are z = 0.98 and L_{0.5-10}=6.3 x 10^{43} erg/s, respectively. A strong
clustering signal is detected at ~18sigma level, which is the most significant
measurement obtained to date for clustering of X-ray selected AGN. By fitting
the projected correlation function w(r_p) with a power law on scales of
r_p=0.3-40 Mpc/h, we derive a best fit comoving correlation length of r_0 = 8.6
+- 0.5 Mpc/h and slope of gamma=1.88 +- 0.07 (Poissonian errors; bootstrap
errors are about a factor of 2 larger). An excess signal is observed in the
range r_p~5-15 Mpc/h, which is due to a large scale structure at z ~ 0.36
containing about 40 AGN. When removing the z ~ 0.36 structure, or computing
w(r_p) in a narrower range around the peak of the redshift distribution (e.g.
z=0.4-1.6), the correlation length decreases to r_0 ~ 5-6 Mpc/h, which is
consistent with that observed for bright optical QSOs at the same redshift.
We investigate the clustering properties of obscured and unobscured AGN
separately. Within the statistical uncertainties, we do not find evidence that
AGN with broad optical lines (BLAGN) cluster differently from AGN without broad
optical lines (non-BLAGN).
The correlation length measured for XMM-COSMOS AGN at z~1 is similar to that
of massive galaxies (stellar mass M_*> 3 x 10^{10} M_sun) at the same redshift.
This suggests that AGN at z~1 are preferentially hosted by massive galaxies, as
observed both in the local and in the distant (z~2) Universe. (shortened)Comment: 16 pages, 11 figures; accepted for publication in A&A. Language
edited versio
Risk assessment for canine leishmaniasis spreading in the north of Italy
Abstract. The incidence of zoonotic visceral leishmaniasis has not only been recognized but is, in fact, increasing in territories of northern continental Italy previously regarded as non-endemic. Recent findings of sporadic autochthonous canine infections and the presence of phlebotomine vectors in some provinces of north-eastern Italy have stimulated risk assessment for the spreading of leishmaniasis in the autonomous province of Bolzano-South Tyrol, the northernmost territory of the Italian eastern Alps. In July 2008, 61 phlebotomine sand flies (Diptera, Psychodidae) were caught and identified as Phlebotomus perniciosus and Sergentomyia minuta. This is the first record in South Tyrol of P. perniciosus, the most competent vector of Leishmania infantum in Mediterranean countries. Leishmania serology on local dogs kept in kennels gave negative results, while only imported canine leishmaniasis cases were reported by local veterinarians through a questionnaire survey. Bio-geographic aspects and epidemiological consequences are analyzed in relation with the risk of leishmaniasis introduction into the area. Keywords: Phlebotomus perniciosus, sand flies, Leishmania infantum, canine, leishmaniasis, Italy