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Oscar D Salomón

Publications and source records attributed to Oscar D Salomón.

10 recordsLinked to original sources

[Transmission of tegumentary leishmaniasis in Argentina].

The total cases of tegumentary leishmaniasis in Argentina increased since 1985, as the frequency, intensity and geographic distribution of the epidemic outbreaks, and the relative incidence in women and children. The characterization of the new scenarios of transmission generated in the last decades is needed for the design of appropriate control measures. With this aim, four outbreaks were described as case studies, based on epidemiological and entomological data together with the qualitative analysis of satellite imaginery: Urugua-i (2004), Esperanza (1998), Alberdi (2003) and Monteros-Simoca (2004). These descriptions allowed to define four scenarios of transmission according to a cycle: a) sylvatic with transmission in primary or residual vegetation; b) sylvatic with eventual peridomestic transmission due to changes within patches of residual vegetation; c) sylvatic with peridomestic transmission in domiciles contiguous with the residual vegetation; and d) peridomestic in rural, ruralized periurban or urban-rural interfase environment. All the epidemic outbreaks since 1985 were consistent with the scenarios characterized here, indicating that the tipification is comprehensive of the transmission of tegumentary leishmaniasis in Argentina up to now. In conclusion, four scenarios of epidemic outbreaks were defined for Argentina, while it is highlighted the qualitative analysis of field and remote sensing data as a tool to understand the epidemiology of the disease, and so to develop adequate measures for prevention and control.

Adult↗

[Phlebotominae: vectors of leishmaniasis in the provinces of Santa Fe and Entre Ríos, Argentina].

The transmission of tegumentary leishmaniasis (TL) has increased in 9 provinces of Argentina since 1985. Santa Fe and Entre Ríos did not record in this period autochtonous probed cases: however, an epidemic outbreak took place in 2003 in Bella Vista, Corrientes, located in an area with ecological continuity and contiguous to both provinces. In order to evaluate the potential risk of transmission of LT, Phlebotominae were captured at locations close to and southern from Bella Vista during February 2004. The traps located on the shores of Parana river in Santa Fe (El Rabón, Villa Ocampo, Cayastá), and Entre Ríos (La Paz. La Celina-Villa Urquiza) captured 860 individuals of Lutzomyia neivai (99.5%) and Lu. migonei (0.5 %), both species with vectorial capacity for Leishmania (V.) braziliensis. In Tartagal, Santa Fe, the captures were consistent with the residual "chaco" landscape, 7 individuals of Lu. nerivai, Lu. migonei and Lu. cortelezzii. The risk of LT epidemic transmission in these provinces is highlighted, mainly due to the progressive southern tropicalization of the paranaense gallery forest. Clinical and entomological surveillance is recommended.

Animals↗

Lutzomyia longipalpis in Clorinda, Formosa province, an area of potential visceral leishmaniasis transmission in Argentina.

Phlebotomine captures were performed during 2004 in Clorinda, Argentina. Clorinda is located across the branches of the Paraguay river in front of Asunción city, Paraguay. Reports of canine and human visceral leishmaniasis in Asunción have been increasing since 1997, however neither leishmaniasis cases nor sand flies were ever recorded from Clorinda. Light traps were located in migration paths (bridges, port), and peridomestic environments of Clorinda and surrounding localities. Lutzomyia longipalpis was found in Clorinda and Puerto Pilcomayo, first report in a potential visceral leishmaniasis transmission area for Argentina. Active surveillance is required immediately in the localities involved and the surrounding area.

Animals↗

Visceral leishmaniasis caused by Leishmania infantum in a Spanish patient in Argentina: What is the origin of the infection? Case report.

BACKGROUND: The question "Where have you been?" is a common one asked by doctors in Northern Europe and America when faced with clinical symptoms not typical of their country. This question must also arise in the clinics of developing countries in which non-autochthonous cases such as the one described here can appear. Important outbreaks of Leishmania infantum have been recorded in the last decade in several Latin American countries but its presence has not yet been recorded in Argentina. We report the first case of visceral leishmaniasis owing to L. infantum in this country. CASE PRESENTATION: A 71-year-old Spanish woman who has been living in Mendoza, Argentina, during the last 40 years presented with a history of high fever and shivering, anemia, leukopenia and splenomegaly over two years. Argentinian doctors did not suspect visceral leishmaniasis even when the histological analysis revealed the presence of "intracytoplasmatic spheroid particles compatible with fungal or parasitic infection". After a serious deterioration in her health, she was taken to Spain where she was evaluated and visceral leishmaniasis was established. Specific identification of the parasite was done by PCR-ELISA, isoenzyme electrophoresis and RAPD-PCR. CONCLUSION: We would like to point out that: i) cases such as the one described here, which appear in non-endemic areas, can pass unnoticed by the clinical physician. ii) in countries in which these introduced cases reside, in-depth parasitological studies are required into vectors and possible reservoirs to rule out the rare case of local infection and, once infection has taken place, to ensure that this does not spread by anthroponotic transmission or a competent reservoir.

Aged↗

Effectiveness of residual spraying of peridomestic ecotopes with deltamethrin and permethrin on Triatoma infestans in rural western Argentina: a district-wide randomized trial.

OBJECTIVE: To compare the effectiveness of a single residual spraying of pyrethroids on the occurrence and abundance of Triatoma infestans in peridomestic ecotopes in rural La Rioja. METHODS: A total of 667 (32.8%) peridomestic sites positive for T. infestans in May 1999 were randomly assigned to treatment within each village, sprayed in December 1999, and reinspected in December 2000. Treatments included 2.5% suspension concentrate (SC) deltamethrin in water at 25 mg active ingredient (a.i.)/m(2) applied with: (a) manual compression sprayers (standard treatment) or (b) power sprayers; (c) 1.5% emulsifiable concentrate (EC) deltamethrin at 25 mg a.i./m(2); and (d) 10% EC cis-permethrin at 170 mg a.i./m(2). EC pyrethroids were diluted in soybean oil and applied with power sprayers. All habitations were sprayed with the standard treatment. FINDINGS: The prevalence of T. infestans 1-year post-spraying was significantly lower in sites treated with SC deltamethrin applied with manual (24%) or power sprayers (31%) than in sites treated with EC deltamethrin (40%) or EC permethrin (53%). The relative odds of infestation and catch of T. infestans 1-year post-spraying significantly increased with the use of EC pyrethroids, the abundance of bugs per site before spraying, total surface, and host numbers. All insecticides had poor residual effects on wooden posts. CONCLUSION: Most of the infestations probably originated from triatomines that survived exposure to insecticides at each site. Despite the standard treatment proving to be the most effective, the current tactics and procedures fail to eliminate peridomestic populations of T. infestans in semiarid rural areas and need to be revised.

Animals↗

Phlebotominae sand flies in Paraguay: abundance distribution in the Southeastern region.

From September 1993 to August 2001, 7,190 phlebotomine were collected with CDC light trap in an endemic area for human leishmaniasis, in the departments of Misiones and Itap a, Paraguay. Eleven species were identified: Lutzomyia neivai (93.7%), L. whitmani (4.1%), and L. fischeri, L. shannoni, L. migonei, L. misionensis, L. cortelezzii, L. pessoai, L. alphabetica, Brumptomyia avellari and B. guimaraesi (less than 1%). The last three species are new records for the country. The biodiversity and phlebotomine abundance were associated with the proximity to primary forest or gallery forest, but L. neivai was also found in peridomestic periurban environment. L. neivai was found throughout the year, and showed a period of higher activity from September to April (spring to fall) with a unimodal or bimodal pattern in relation to the annual rainy peaks during the summer. Background literature about phlebotomine from Paraguay has been reviewed.

Animals↗

Epidemiological and clinical aspects of scorpionism by Tityus trivittatus in Argentina.

This is a descriptive study of epidemiological and clinical aspects of stings caused by the scorpion Tityus trivittatus in Argentina. We analyzed 511 cases recorded from different health centers in 22 provinces. Most accidents took place during the period November-April (76%), in or nearby houses (86%). Over 50% of the accidents involved children and teenagers. Envenomation by T. trivittatus was mainly characterized by local symptoms: pain (85%), edema (26.6%), burning sensation (24.7%), erythema (20.7%), local hyperthermia (13.1%), paresthesia (9.8%) and general manifestations such as vomiting (25%), paleness (18.8%), headache (11.4%) and sweating (8.2%). Neurological, cardiovascular and respiratory disorders were uncommon. Almost 90% of the injured people got treated with specific antivenom within 2 h, 6% were treated 2-h after the accident and only 2 people were treated 12 or more hours after being stung. The global mortality recorded was 6 per 1000 cases. Scorpionism in Argentina is a public health problem under control due to the relatively low incidence and the accessibility of specific antivenom.

Adolescent↗

[Poisoning by spiders of Loxosceles genus].

Despite the great number of spiders in the world, only a small group of them is capable of producing death in humans. In Argentina, there are only three of the four genera of spiders considered of high risk to humans: Latrodectus is present in rural areas, Phoneutria is restricted to small regions while Loxosceles is distributed throughout the country. Accidents by Loxosceles represent around 4% of the total number produced by venomous animals in Argentina. The bite is accidental and may produce considerable local necrosis with scar formation and ulcers of slow and difficult healing that may require surgical repair. Some bitten people may suffer from intravascular hemolysis, disseminated coagulation and acute renal insufficiency leading to death. Despite the great number of studies performed on Loxosceles venoms, at present, the physiopathological course of poisoning is not clear and there is not common criteria for its treatment. In this review, biological and epidemiological data of this spider are described as well as the venom composition and the possible participation of its components in the poisoning. These data provide biological and biochemical tools to understand the course of poisoning and to have better criteria for the treatment and prevention of these accidents and their complications.

Animals↗

[Tegumental leishmaniasis in Las Lomitas, Province of Formosa, Argentina, 1992-2001].

Las Lomitas Hospital reported 85 cases of tegumentary leishmaniasis between 1992 and 2001. The cases were males (72.9%), 91.8% older than 10 years, 10.5% presented mucosae involvement. A single ulcer on lower limbs was the most frequent manifestation. The epidemiological and clinical patterns were consistent with the infection due to Leishmania (Viannia) braziliensis. The annual distribution of ulcers onset was bimodal, the frequency of cases had a significant association with the Bermejo river volume, and the rainfall of the previous year. Intradermoreaction and recalling questions suggested that fishing in the river was the main risk activity. Among 1018 Phlebotominae collected, 97.1% were Lutzomyia neivai, 2.3% L. migonei and 0.6% L. cortelezzii (0.6%), the peridomestic/gallery forest of the Bermejo river proportion was 1/9, with similar composition to the populations around the same river in Salta province. The increase of cases since 1992, the ongoing environmental changes due to developmental works, and the potential installation of a periurban transmission cycle, require an active surveillance of cases and entomological components in the Chaco region.

Adolescent↗

[Poisoning by bee sting].

Among the human pathologies produced by venomous animals, bee stings constitute the largest number of accidents in several countries, exceeding the mortality rate caused by other venomous animals such as snakes, spiders or scorpions. The clinical picture after the bee sting may include anaphylaxis or poisoning. The latter is produced by massive attacks and is a serious problem that may put the patient's life at risk. People that are poisoned display hemolysis, rhabdomiolysis and acute renal failure that together with other systemic failures can bring about death. The knowledge of the physiopathological mechanisms involved in the massive attack of bees is crucial for health care professionals as to date we do not have antivenoms with proven clinical efficacy. In this review we include the bee's biological aspects, venom composition and its relation with the occurrence and severity of accidents as well as epidemiological data that can be useful for this type of accidents.

Animals↗