PubMed Health⌕ Search

Biomedical subjects

R Romi

Publications and source records attributed to R Romi.

At least 19 recordsLinked to original sources
PubMed2006

High levels of human chitotriosidase hinder the formation of peritrophic membrane in anopheline vectors.

In the Anopheles midgut, Plasmodium falciparum produces a specific chitinase able to penetrate the blood meal surrounding the chitin-containing peritrophic membrane (PM). High levels of an analogous chitinase, chitotriosidase (CHIT), may be found in human blood, being the markers of macrophage activation. To verify the hypothesis that CHIT present in malaria patient blood could help parasite to overcome PM, we carried out a bioassay by feeding Anopheles stephensi females on an artificial apparatus that contained human blood from four different sources and with different chitinase concentrations: (1) healthy donors, as negative controls; (2) patients with malaria; (3) patients with Gaucher disease; and (4) whole blood enriched with commercial P. falciparum chitinase, as positive controls. After 16, 20 and 24 h of bloodfeeding, mosquitoes were dissected to extract the midgut and assess the effect of the different chitinases on membrane structure. Optical microscopy showed that formation of PM was clearly complete after 16 h in the posterior midgut from Anopheles already fed with healthy donor bloods. By contrast, PM formation was visible after 16 h in the posterior midgut of mosquitoes fed with malaria and Gaucher patient bloods but appeared clearly damaged at 20 and 24 h. At the same time, the PM formation was almost completely inhibited in the midgut of Anopheles fed with P. falciparum chitinase-enriched bloods. These alterations were clearly confirmed by transmission electronic microscopy. In the present paper, we demonstrate that human CHIT from different sources is active on anophelines' PM.

Animals↗
PubMed2006

Laboratory evaluation of the bioinsecticide Spinosad for mosquito control.

Spinosad, a naturally occurring product of the fermentation of the bacterium Saccharopolyspora spinosa, is a highly effective bioinsecticide against a broad range of agriculturally important insect pests, and this agent has an excellent environmental and mammalian toxicological profile. In this study the efficacy of a Spinosad-based product (Laser 4.8% emulsifiable concentrate) was evaluated in laboratory bioassays against laboratory-reared mosquito strains of 3 species of medical importance: Aedes aegypti, Anopheles stephensi, and Culex pipiens. Spinosad was particularly effective against larval Aedes and Culex, with a less marked activity against anophelines (24-h median lethal concentration = 0.0096, 0.0064, and 0.039 mg/liter, respectively), showing a persistence of the insecticide action of about 6 wk in laboratory containers. The activity of the Spinosad-based product against adult mosquitoes (toxicity by ingestion and a possible irritant or repellent effect on gravid females) also was evaluated. Results are discussed and compared with those available in the literature.

Aedes↗
PubMed2004

Potential vectors of West Nile virus following an equine disease outbreak in Italy.

In the late summer of 1998, an outbreak of equine encephalomyelitis due to West Nile virus (WNV) occurred in the Tuscany region of central Italy. The disease was detected in 14 race horses from nine localities in four Provinces: Firenze, Lucca, Pisa and Pistoia. The outbreak area included Fucecchio wetlands (1800 ha), the largest inland marsh in Italy, and the adjacent hilly Cerbaie woodlands with farms breeding horses. To detect potential vectors of WNV, entomological surveys of Fucecchio and Cerbaie were undertaken during 1999-2002 by collecting mosquito larvae from breeding sites and adult mosquitoes by several methods of sampling. Among 6023 mosquitoes (Diptera: Culicidae) collected, 11 species were identified: Aedes albopictus (Skuse), Ae. vexans (Meigen), Anopheles atroparvus Van Thiel, An. maculipennis Meigen s.s., An. plumbeus Stephens, Culex impudicus Ficalbi, Cx. pipiens L., Culiseta longiareolata Macquart), Ochlerotatus caspius (Pallas), Oc. detritus (Haliday) and Oc. geniculatus (Olivier). In Fucecchio marshes, Cx. impudicus predominated with seasonal peak densities in spring and autumn: its greatest abundance during early spring coincides with arrival of migratory birds from Africa. In Cerbaie hills, Cx. pipiens predominated with peak population density in late summer. No viruses were isolated from 665 mosquitoes processed. These findings, plus other data on Italian mosquito bionomics, suggest a possible mode of WNV transmission involving the most abundant Culex in the Fucecchio-Cerbaie areas. Culex impudicus, being partly ornithophilic, might transmit WNV from migratory to non-migratory birds during springtime; Cx. pipiens, having a broader host range, would be more likely to transmit WNV from birds to horses and, perhaps, to humans by late summer.

Animals↗
PubMed2003

First finding of Dirofilaria repens in a natural population of Aedes albopictus.

The invasive mosquito Aedes albopictus (Skuse) (Diptera: Culicidae) has become widespread in Italy during the past decade. Also Italy has foci of canine filariasis caused by Dirofilaria (Spirurida: Onchocercidae), due to subcutaneous D. repens Railliet & Henry as well as the dog heartworm D. immitis (Leidy) transmitted by various vector mosquitoes (Diptera: Culicidae). In 2002, at Fiumicino, west of Rome (Lazio Region), 17% of dogs were found to have D. repens microfilariae in peripheral blood. To evaluate the role of Ae. albopictus as a vector of Dirofilaria in this area, female mosquitoes were collected daily, June-October 2002, landing on dog or human bait in a rural house at Focene. Mosquitoes were maintained at 27 degrees C and 70% RH for 6 days, to allow development or purging of filaria larvae, then identified and frozen for subsequent molecular assay with filaria-specific ribosomal S2-S16 primers. To distinguish specimens harbouring infective L3 Dirofilaria larvae, DNA was extracted separately from the mosquito abdomen and head-thorax. Dirofilaria species were identified by sequencing, confirmed by polymerase chain reaction of positive specimens using primers specific for D. immitis and D. repens. Dirofilaria DNA was detected in 3/154 (2%) of Ae. albopictus females examined: D. repens DNA in head-thorax and abdomen of one collected 27th July; D. immitis in the abdomen of one collected 24th September; DNA of both D. immitis and D. repens in the head-thorax of one collected 11th October 2002. Thus Ae. albopictus is a potential vector of both Dirofilarias in Italy, representing risks for veterinary and human health.

Aedes↗
PubMed2002

Anopheles sacharovi (Diptera: Culicidae): a reemerging malaria vector in the Ararat Valley of Armenia.

In 1994, the first indigenous case of malaria since the 1960s was reported in Armenia, and the number of cases quickly increased in the ensuing years. In 1998, a roll-back malaria program was developed to eliminate the recently established foci of malaria infection and to prevent the reestablishment of malaria in Armenia. As part of this program, we carried out entomological surveys to identify the potential malaria vectors in the Ararat Valley, the area where most of the indigenous malaria cases had been reported. In particular, we attempted to ascertain the presence of Anopheles sacharovi Favre, which is historically the most important malaria vector in Armenia yet which had not been reported since 1965. In 1998-2000, we collected adult mosquitoes and larvae in the city of Masis and in three rural villages of the Ararat Valley. Species identification of the members of the Anopheles maculipennis complex was performed through egg and larval morphology, heteroduplex analysis, and sequencing of the second internal transcribed spacer of ribosomal DNA. Two species of the complex were identified: An. sacharovi, found in all of the study sites, andAn. maculipennis s.s. Meigen, the most common species in the area. The reemergence of An. sacharovi in the study sites shows that the receptivity for malaria is still high in the Ararat Valley and, likely, in other regions of Armenia.

Animals↗
PubMed2002

Impact of the malaria control campaign (1993-1998) in the highlands of Madagascar: parasitological and entomological data.

Malaria transmission in the central highlands of Madagascar was interrupted in the 1960s by a national control program that used DDT indoor spraying and mass treatment with chloroquine. At the end of the 1980s in this region, epidemic malaria reappeared. Italian health authorities provided technical assistance to the National Malaria Control Program since the beginning of the resurgence of malaria in the central highlands. Yearly residual house spraying performed for 5 years (1993-1998) and the availability of antimalarial drugs reduced malaria transmission to very low levels, with improvement in parasitologic and entomologic indexes. A significant reduction of malaria prevalence was observed in the villages located at altitudes of 1,000-1,500 m, corresponding to the stratum of unstable malaria that was the main target of the antivector interventions. A significant reduction of malaria prevalence was also observed in the villages located at altitudes of 900-1,000 m, where malaria transmission is stable. The main vector Anopheles funestus was dramatically reduced in abundance and distribution in the sprayed areas.

Adolescent↗
PubMed2001

Malaria incidence and mortality in Italy in 1999-2000.

In 1999-2000, a total of 2060 malaria cases were reported by the ISS. Most of the patients took inappropriate treatments or did not have any prophylaxis. Ninety-three per cent became infected in African malarious countries, 4% in Asian countries, and 3% in Latin America. P. falciparum accounted for 84% of the cases, followed by P. vivax (8%), P. ovale (5%), and P. malariae (2%). Deaths corresponded to an annual case fatality rate of 0.3% in 1999 and 0.5% in 2000. In general, imported malaria cases reflect the number of Italian travellers who underestimate the infection risk in Asian and Latin American malarious countries and permanent residents of African origin who visit their relatives in their native countries.

Humans↗
PubMed2001

[Aedes albopictus in Italy: an underestimated health problem].

Since 1990, Ae. albopictus has spread in 9 regions and 30 provinces of the country. This species was introduced in Italy in shipments of scrap tires form the USA. In Italy, Ae. albopictus is the major biting pest throughout much of its range and, although there is no evidence that this mosquito is the vector of human disease in the country, the species might be involved in the transmission of some arboviruses which have been reported in the Mediterranean Basin. Aim of this paper is to provide an update on the distribution of Ae. albopictus in Italy and to renew the interest in a problem frequently underestimated. Public health implications after a ten-year presence of the species are also discussed.

Aedes↗
PubMed2001

[Aedes albopictus in Rome: monitoring in the 3-year period of 1998-2000].

Aedes albopictus was first reported in Italy in 1990 and in the urban area of Rome in the late summer 1997. Ae. albopictus is a daytime, outdoor mosquito, that bite preferably on man. In Rome (42 degrees South of latitude), larvae are found from March to November, but some adult females are active until December. The peak of adult abundance, and then of the annoyance caused to man, occurs in late August-September. The presence of the species in Rome represents the first example in Italy of extensive colonization of an urban area, with involvement of hundred-thousand people. Since 1997, Ae. albopictus has spread quickly from the initial foci to the whole city. In 2000, scattered foci of the species have been reported throughout the urban area and in some towns of the province.

Aedes↗
PubMed2000

Identification of the sibling species of the Anopheles maculipennis complex by heteroduplex analysis.

The group of anopheline mosquitoes referred to as 'Anopheles maculipennis complex' includes the most important malaria vectors of the Palearctic Western region. The species belonging to this complex, however, are difficult or impossible to distinguish by morphological characters. To differentiate sibling palearctic species belonging to this complex, interspecific differences in the ITS2 sequences were used to set up a rapid and sensitive diagnostic tool based on heteroduplex analysis. The relative heteroduplex mobility allowed the following seven species to be readily distinguished: An. atroparvus, An. labranchiae, An. maculipennis s.s. , An. martinius, An melanoon, An. messeae and An. sacharovi.

Animals↗
PubMed2000

Laboratory and field evaluation of metallic copper on Aedes albopictus (Diptera: Culicidae) larval development.

Laboratory bioassays and field trials were carried out to study the effect of metallic copper on the development of Aedes albopictus (Skuse). Multiwire electric cable was used as a source of metallic copper. Three different doses were used in laboratory tests (5, 10, and 20 g/liter) and two in field tests (20 and 40 g/liter). In the laboratory, 10 g/liter induced high mortality and a lack of development in Ae. albopictus larvae and doses of 20 g/liter completely inhibited development. Larval mortality was higher in earlier instars than in third through fourth instars and pupae. No effects were reported on egg hatching. Copper ion concentration in water increased up to 574 ppb for 5 g/liter dose, 710 ppb for 10 g/liter dose, and 1,210 ppb for 20 g/liter dose, within week 6. The increasing concentration of copper in water was correlated positively with the decreasing production of adults. Copper ions concentration < 500 ppb did not or only slightly affected larval development and mortality of Ae. albopictus in laboratory tests. Copper concentrations between 500 and 1,000 ppb delayed larval development and caused high mortality. Copper concentrations > 1,000 ppb inhibited larval development completely killing all the larvae. This last result has been achieved by the use of a 20 g/liter dose of metallic copper in water. Copper also affected adult weight. In field trials, 20 g/liter reduced the number of larvae in treated pots by 90%, and 40 g/liter completely prevented oviposition. Moreover, the persistence of the toxic action of metallic copper in the field lasted for several months.

Aedes↗
PubMed2000

[Insecticide sensitivity in malaria vectors in high altitude Madagascar after five years of vector control].

In 1991, Anopheles gambiae and Anopheles funestus, the main malaria vectors in the Highlands of Madagascar, were reported to be fully susceptible to DDT; nevertheless a slight decrease in the susceptibility levels was recorded when compared with previous assays carried out in 1962. From 1993 to 1997, five cycles of indoor residual spraying have been carried out in the Highlands: a total of 1,482,000 kg of 70% wp DDT have been used for the treatment of houses and animal shelters. From 1996 to 1999, adult mosquito susceptibility tests to DDT and to some pyrethroids (lambdacyalothrine, deltamethrine, permethrine and cyfluthrine) have been carried out on samples collected in 20 areas of the Highlands. Bioassays were carried out following the WHO standard method. All tested populations of An. funestus showed a full susceptibility to DDT. An. gambiae showed a widespread decrease in the susceptibility to DDT, particularly marked in the region of the capital city Antananarivo. Both species were susceptible to pyrethroids.

Adult↗
PubMed1999

Phylogenetic relationships of seven palearctic members of the maculipennis complex inferred from ITS2 sequence analysis.

The sequences of the second internal transcribed spacer (ITS2) of ribosomal DNA (rDNA) were determined from seven palearctic mosquitoes species belonging to the Anopheles maculipennis species complex, namely An. atroparvus, An. labranchiae, An. maculipennis, An. messeae, An. melanoon, An. sacharovi and An. martinius. The length of the ITS2 ranged from 280 to 300 bp, with a GC content of 49.4-54.1%. With the exception of An. messeae, negligible levels of intraspecific polymorphism and no intrapopulation variation were observed. The phylogenetic relationships among the members of the maculipennis complex were inferred by maximum-parsimony analysis of the PAUP program and the neighbour-joining and maximum-likelihood analysis of the PHYLIP program. All of the trees obtained were almost identical in topology, although the relationships among three species, i.e. An. maculipennis, An. messeae and An. melanoon, remained unresolved. The phylogenies were in good agreement with the previous gene-enzyme and polytene chromosome banding pattern studies.

Animals↗
PubMed1999

Current status of Aedes albopictus and Aedes atropalpus in Italy.

Eight years after the 1st record in Italy, scattered foci of Aedes albopictus are reported in 9 regions and 107 municipalities belonging to 22 provinces, mainly located in the northeastern part of the country (Veneto region). In almost all infested areas the species is well controlled and at low levels of density, through source reduction and antilarval treatments. Aedes atropalpus, 1st recorded in 1996, remains limited to the original focus in the province of Treviso. Surveillance and control of both species are carried out by local health agencies within a national program coordinated by Istituto Superiore di Sanità (national Institute of Public Health).

Aedes↗
PubMed1998

Malaria in Maremma, Italy.

BACKGROUND: In August, 1997, a woman with no history of travel to malarious regions developed Plasmodium vivax malaria. She lived in a rural area of Italy where indigenous Anophyles labranchiae mosquitoes were present. METHODS AND FINDINGS: An environmental investigation was done within a 3 km radius of the patient's house. Adult mosquitoes and larvae were collected and examined by PCR with the gene for plasmodium circumsporozoite protein as target. About 200 people living in the area were interviewed to detect possible carriers of P. vivax. FINDINGS: None of the mosquitoes captured were carrying any malarial organisms. The house-to-house investigation identified a 7-year-old girl who had had a feverish illness a few days after her arrival in Italy from India, and who, 3 months later, still had P. vivax in her blood; she and her mother had antimalarial antibodies. INTERPRETATION: These investigations suggest that the index case of malaria was caused by local anopheline mosquitoes infected with exogenous P. vivax.

Animals↗
PubMed1998

[Zooprophylaxis: old and new problems].

In the present note the authors report on the most important works which have examined the application of zooprophylaxis as a means for malaria control from the onset of this century to the present day. The method of zooprophylaxis has evolved throughout the years in close connection with other problems, undoubtedly more important in the history of malaria, which in the present paper are amply discussed. From the very beginning this subject was the object of heated debates by those who retained it a valid method of malaria control and those who denied its validity, among whom some of the most important Italian and foreign malariologists. The experiments of zooprophylaxis received most attention in the twenties, but, following the works of Missiroli and co-workers in the early thirties by which the varieties of the "complex maculipennis" were identified, the interest on zooprophylaxis was less heightened. It should be noted, however, that the increase of cattle, and especially land reclamation, reduced considerably malaria endemicity in northern Italy where zoophilic varieties were most prevalent. Recently, renewed interest on zooprophylaxis has been shown in Pakistan, where some experiments on the use of cattle have led to an unexpected increase of malaria transmission.

Animals↗