33 research outputs found
Molecular Diagnosis of Malaria Infection: A Survey in a Hospital in Central Italy
Malaria is a dramatic disease caused by the protozoan parasites Plasmodium. The diagnosis is mainly based on microscopy and rapid
diagnostic tests (RDT). Molecular approaches based on PCR techniques may be an alternative tool particularly favourable in regions with
declining prevalence. This work aimed to assess pros and cons of molecular diagnosis of malaria in a district of Central Italy were several tens
of imported malaria cases are diagnosed every year. Thirty-three blood samples were analysed by microscopy, RDT and molecular techniques to
monitor the relative efficiency in malaria diagnosis. Molecular analysis and microscopy diagnosed 32 out of 33 samples as positive for malaria,
while RDT only 29. More differences concerned the diagnosis of mixed infections. Our findings remark the importance of the molecular approach
in supporting and improving malaria diagnosis. In the cases here presented, the molecular analysis was particularly useful to unveil parasites
presence in infections not detectable by blood smear analysis and to additionally solve real and/or presumed mixed infections
The mosquito microbiota: a new way to look at mosquito vectors and to investigate other insect pests
I. Ricci, C. Damiani, P. Rossi, A. Capone, P. Scuppa, A. Cappelli, U. Ulissi, M. Mosca, M. Valzano, S. Epis, E. Crotti, D. Daffonchio, A. Alma, L. Sacchi, M. Mandrioli, C. Bandi & G. Favia, Mosquito symbioses: from basic research to the paratransgenic control of mosquito-borne diseases, J. Appl. Entomol. 135 (2011) 487–493\ud
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Guido Favia, Irene Ricci, Patrizia Scuppa, Claudia Damiani, Paolo Rossi, Aida Capone, Chenoa De Freece, Matteo Valzano, Alessia Cappelli, Michela Mosca and Ulisse Ulissi, Facing\ud
Malaria Parasite with Mosquito Symbionts\ud
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Irene Ricci, Matteo Valzano, Ulisse Ulissi, Sara Epis, Alessia Cappelli, Guido Favia, Symbiotic control of mosquito borne disease\ud
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M. Valzano, G. Achille, F. Burzacca, I. Ricci, C. Damiani, P. Scuppa, G. Favia, Deciphering microbiota associated to Rhynchophorus ferrugineus in Italian samples: a preliminary study, Journal of Entomological and Acarological Research 2012; volume 44:e16\u
Symbiotic Control of mosquito borne disease
It is well accepted that the symbiotic relationships insects have established with several
microorganisms have had a key role in their evolutionary success. Bacterial symbiosis is also
prevalent in insects that are efficient disease vectors, and numerous studies have sought to decrypt
the basic mechanisms of the host-symbiont relationships and develop ways to control vector borne
diseases. "Symbiotic control", a new multi-faceted approach that uses symbiotic microorganisms to
control insect pests or reduce vector competence, seems particularly promising. Three such
approaches currently at the cutting edge are: i) the disruption of microbial symbionts required by
insect pests; ii) the manipulation of symbionts that can express anti-pathogen molecules within the
host; and iii) the introduction of endogenous microbes that affect life-span and vector capacity of
the new hosts in insect populations.
This work reviews current knowledge on microbial symbiosis in mosquitoes that holds promise for
development of symbiotic control for mosquito borne diseases
Deciphering microbiota associated to Rhynchophorus ferrugineus in Italian samples: a preliminary study
The Red Palm Weevil, Rhynchophorus ferrugineus (Olivier, 1790) is
the most dangerous and deadly pest of date, coconut, oil, sago and
other palms. Recently introduced in the Mediterranean basin, it
became the most relevant insect pest for ornamental palms in the
urban environment. Given the development of an innovative control
method based on symbiotic control, we have performed a pilot project
to decrypt the microbiota associated to both adults and larval stages of
the insect to identify potential tools for biocontrol agents against the
Palm Weevil. A number of bacterial species were found associated with
the insect. In particular, species of the genera Lactococcus, Proteus,
and others were detected
Detection and isolation of the α-proteobacterium Asaia in Culex mosquitoes.
Investigations of microbiota within mosquitoes continue to widen the
spectrum of possible symbiont-based applications against vector-borne diseases. In
this context, α-proteobacteria of the genus Asaia (Rhodospirillales: Acetobacteraceae)
are emerging as possible endosymbiotic candidates, particularly in paratransgenic
approaches aimed at interrupting pathogen transmission. Previous studies have
shown that Asaia spp. distribution among Anopheles gambiae and Anopheles
stephensi (Diptera: Culicidae) mosquitoes displayed positive rates of infection in
isolated midguts, salivary glands and reproductive tissues. Similarly, Asaia has been
detected in Aedes albopictus (Stegomyia albopicta) and Aedes aegypti (Stegomyia
aegypti ) (Diptera: Culicidae) populations. Within the Culex pipiens complex (Diptera:
Culicidae), Asaia infection is still largely unexplored. Here, we summarize a
preliminary survey of laboratory-reared Cx. pipiens complex and field-collected Culex
quinquefasciatus for the presence of Asaia spp., and present the first identification of
Asaia in some of the members of the Cx. pipiens complex and the first description in
West African populations of Cx. quinquefasciatus
Killer yeasts exert anti-plasmodial activities against the malaria parasite Plasmodium berghei in the vector mosquito Anopheles stephensi and in mice
Wickerhamomyces anomalus is a yeast associated with different insects including mosquitoes, where it is proposed to be involved in symbiotic relationships with hosts. Different symbiotic strains of W. anomalus display a killer phenotype mediated by protein toxins with broad-spectrum antimicrobial activities. In particular, a killer toxin purified from a W. anomalus strain (WaF17.12), previously isolated from the malaria vector mosquito Anopheles stephensi, has shown strong in vitro anti-plasmodial activity against early sporogonic stages of the murine malaria parasite Plasmodium berghei
Asaia Activates Immune Genes in Mosquito Eliciting an Anti-Plasmodium Response: Implications in Malaria Control
In mosquitoes, the discovery of the numerous interactions between components of the microbiota and the host immune response opens up the attractive possibility of the development of novel control strategies against mosquito borne diseases. We have focused our attention to Asaia, a symbiont of several mosquito vectors who has been proposed as one of the most potential tool for paratransgenic applications; although being extensively characterized, its interactions with the mosquito immune system has never been investigated. Here we report a study aimed at describing the interactions between Asaia and the immune system of two vectors of malaria, Anophelesstephensi and An. gambiae. The introduction of Asaia isolates induced the activation of the basal level of mosquito immunity and lower the development of malaria parasite in An. stephensi. These findings confirm and expand the potential of Asaia in mosquito borne diseases control, not only through paratransgenesis, but also as a natural effector for mosquito immune priming
Denaturing Gradient Gel Electrophoresis Analysis of Bacteria in Italian Ticks and First Detection of Streptococcus equi in Rhipicephalus bursa from the Lazio Region
Tick-borne diseases are an increasing problem for the community. Ticks harbor a complex microbial population acquired while feeding on a variety of animals. Profiling the bacterial population by 16S rDNA amplification and denaturing gradient gel electrophoresis enables detection of the broad spectrum of bacteria that settles in the ticks. This study identified known and unknown tick-infecting bacteria in samples from Italy. Seven adult ticks from different hosts and origins were analyzed: two Rhipicephalus sanguineus ticks from dogs (Lombardia), two Rhipicephalus bursa ticks from bovines (Lazio), and three Ixodes ricinus ticks from humans (Marche). The major result was the first report of the zoonotic agent Streptococcus equi in ticks. S. equi is a species complex of highly contagious pathogens. Subsequent to S. equi detection in a R. bursa tick removed from a bovine of Lazio in 2012, we studied 95 R. bursa samples collected from 3 bovines, 3 ponies, and 1 sheep grazing in the same area in 2012 and from 6 ponies grazing there in 2017. The results of a specific PCR assay indicated a not sporadic occurrence of S. equi in ticks. This finding provides a basis for assessing the potential of ticks to harbor and disperse S. equi