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At least 127 records · Page 7Linked to original sources
PubMed2003

[Prevalence of hepatitis B, hepatitis C and syphilis in female sex workers in Venezuela].

OBJECTIVE: In Venezuela, female sex workers are submitted to a preventive control of syphilis and human immunodeficiency virus (HIV). However, other very important sexually transmitted infections are not evaluated. A study was carried out to identify the sociocultural background of a group of sex workers and its association with the seroprevalence of hepatitis B and C markers, in addition to routine evaluation. METHOD: A total of 212 female sex workers who attended the control center of sexually transmitted infections (STI) in the city of Los Teques, Venezuela, were evaluated. Women were asked their age, educational background, use of contraceptive methods and condoms. Blood was drawn to determine the prevalence of syphilis, hepatitis B surface antigen (HBsAg), antibodies to hepatitis B core (anti-HBc), hepatitis C (anti-HCV) and HIV. RESULTS: The prevalence of syphilis was 2.4%, seroprevalence of anti-HCV was 0.5%, HBsAg 3.8% and anti-HBc 13.8%. No cases of HIV were observed. Higher prevalence of hepatitis B markers was associated with a lower level of education (p<0.05) and higher age (p<0.05). It was found that 38.5% of participant women never used condoms and 25.6% did not use any contraceptive method. CONCLUSION: It could be necessary to implement preventive programs to immunize sex workers against hepatitis B virus as well as education programs on condom use for their protection against sexually transmitted infections.

Adolescent↗
PubMedDate not supplied

Colonization and laboratory maintenance of Anopheles albimanus Wiedemann in Venezuela.

Anopheles albimanus is one of the main vectors of malaria in Central America and the Caribbean, based on its importance, there are previous reports of the successful colonization of this species in Latin America countries. Mosquitoes were collected in the Aragua State of Venezuela colonized in the laboratory, using a simple and efficient maintenance method. Based on life table calculations under well established laboratory conditions, the Survival Rate Probability was constant and always close to 1 in immature stages, the Reproductive Net Rate (Ro) was 3.83, the generation time (Tc) was 24.5 days and the Intrinsic Growth Rate (rm) was 0.0558. This is the first report of the colonization of A. albimanus in Venezuela.

Animals↗
PubMedDate not supplied

Zoonotic cutaneous leishmaniasis due to Leishmania (Viannia) braziliensis associated with domestic animals in Venezuela and Brazil.

After outbreaks of cutaneous leishmaniasis in Solano State, Venezuela, 5% of the population had parasitized ulcers while after similar outbreaks in Mesquita, Rio de Janeiro State, Brazil, 9% had the disease. In these foci children, including some under six years of age, were affected. There was no significant difference in the occurrence of the disease according to sex or type of employment. In Solano, 3% of dogs and 28% of donkeys had parasitized lesions, while in Mesquita these indices were 19.8% and 30.8% respectively. The parasite from man, dogs and equines was identified as Leishmania (Viannia) braziliensis, by zymodeme and serodeme characterization. In these foci there is evidence suggesting that leishmaniasis is a zoonosis, possibly with equines and dogs as reservoirs, although both a wild enzootic cycle and the role of man as a source of infection can not be ruled out. Transmission is assumed to occur peridomestically by sandfly vectors such as Lutzomyia panamensis in Venezuela and Lutzomyia intermedia in Brazil. Information about the origin of these foci suggests that infected equines may be an important factor in the dissemination of the parasite in a peridomestic situation where these sandflies are abundant.

Adolescent↗
PubMed1992

Field evaluation of an exoantigen-containing Babesia vaccine in Venezuela.

Bovine babesiosis is endemic in Venezuela, causing significant losses in highly susceptible imported cattle. Current immunoprophylactic methods include the less desirable use of live parasites. Inactivated vaccines derived from exoantigen-containing supernatant fluids of in vitro Babesia bovis and B. bigemina cultures have been developed and constitute a major improvement in vaccine safety, stability and ease of handling. Vaccination trials conducted under field conditions provide the final evaluation of a culture-derived B. bovis-B. bigemina vaccine. During a 5-year period, approximately 8,000 cattle were vaccinated and 16 clinical trials carried out in 7 states of Venezuela. Clinical, serologic and parasitologic data were collected monthly from 10% of the animals over a 2-year period. Data were also collected from a similar number of nonvaccinated control cattle. Analysis of results from these trials demonstrated a reduction in the incidence of clinical disease among vaccinated animals and complete protection against mortality caused by babesiosis. Vaccine efficacy was measured calculating the incidence rates of disease and mortality among vaccinated and nonvaccinated cattle. Use of this inactivated vaccine offers the best combination of safety, potency and efficacy for the effective immunoprophylactic control of bovine babesiosis.

Animals↗
PubMedDate not supplied

Identification of planorbids from Venezuela by polymerase chain reaction amplification and restriction fragment length polymorphism of internal transcriber spacer of the RNA ribosomal gene.

Snails of the genus Biomphalaria from Venezuela were subjected to morphological assessment as well as polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) analysis. Morphological identification was carried out by comparison of characters of the shell and the male and female reproductive apparatus. The PCR-RFLP involved amplification of the internal spacer region ITS1 and ITS2 of the RNA ribosomal gene and subsequent digestion of this fragment by the restriction enzymes DdeI, MnlI, HaeIII and MspI. The planorbids were compared with snails of the same species and others reported from Venezuela and present in Brazil, Cuba and Mexico. All the enzymes showed a specific profile for each species, that of DdeI being the clearest. The snails were identified as B. glabrata, B. prona and B. kuhniana.

Animals↗
PubMed2004

Intestinal helminths of capybaras, Hydrochoerus hydrochaeris, from Venezuela.

Quantitative parameters of intestinal helminth species and their potential relations to host characteristics in a population of capybaras (Hydrochoerus hydrochaeris) from Venezuela are reported for the first time. The intestines of 40 capybaras were collected during the 1992-annual harvest at Hato El Cedral. Six helminth species were found: 2 cestodes (Monoecocestus macrobursatum, M. hagmanni), 2 nematodes (Viannella hydrochoeri, Protozoophaga obesa), and 2 trematodes (Hippocrepis hippocrepis, Taxorchis schistocotyle). This is the first report for M. macrobursatum in Venezuela. Helminth abundance did not differ between sexes or age classes. Although patterns of distribution for all helminth species were overdispersed, the high prevalence found for all species (over 70%) and the high abundance observed for nematodes made it difficult to assess the effect that these helminths may produce on capybaras. Nevertheless, the negative associations found between the body condition of capybaras and helminth intensity for M. macrobursatum and V. hydrochoeri, might be pointing out potential host population regulatory role for these parasites which require further research.

Animals↗
PubMed2005

Update on Chagas disease in Venezuela--a review.

The present article reviews the status of Chagas disease in Venezuela based on the detection of Trypanosoma cruzi infections both in referred patients with clinical presumptive diagnosis (1988-2002) and in individuals sampled from rural localities representative of the different geographical regions of the country (1995-2002). In the former group from 306 individuals examined, 174 (56.8%) were seropositive to T. cruzi; 73 (42%) in the acute phase with 52 (71%) showing blood circulating parasites, and from these 38% were children under 10 years old. The other 101 (58%) showed chronic infection at different degrees of cardiac complication. In addition, serologic examination of 3835 individuals from rural areas revealed 11.7% seroprevalence. From these, 8.5% (38/448) were children aged from 0 to 10 years old. These figures suggest that Chagas disease may be re-emerging in Venezuela judging for the active transmission detected during the last decade. The success of the Venezuelan anti-chagasic campaign during the last 40 years is evaluated in the frame of the present results. The epidemiological situation is discussed and recommendation to consider Chagas disease as a national priority is given.

Acute Disease↗
PubMed2006

Population genetic structure of the dengue mosquito Aedes aegypti in Venezuela.

The mosquito Aedes aegypti is the main vector of dengue in Venezuela. The genetic structure of this vector was investigated in 24 samples collected from eight geographic regions separated by up to 1160 km. We examined the distribution of a 359-basepair region of the NADH dehydrogenase subunit 4 mitochondrial gene among 1144 Ae. aegypti from eight collections. This gene was amplified by the polymerase chain reaction and tested for variation using single strand conformation polymorphism analysis. Seven haplotypes were detected throughout Venezuela and these were sorted into two clades. Significant differentiation was detected among collections and these were genetically isolated by distance.

Aedes↗
PubMed2004

[Prevalence of Blastocystis hominis among food handlers from Caroni municipality, Bolivar State, Venezuela].

A cross-sectional survey was conducted to determine the prevalence of Blastocystis hominis infection in a random sample of apparently healthy food handlers. A total of 415 individuals attending the Manoa Urban Outpatient Clinic (Caroní Municipality, Bolívar State, Venezuela) in the Adult Hygiene Program and who requested health certification to work as food handlers were studied. Stool samples obtained by spontaneous evacuation were examined by direct microscopy and the Willis concentration method. A total of 150 individuals were infected (36.14%), 107 (25.78%) of whom with B. hominis. There was no difference between males and females (p > 0.05), but there was a significant difference between ages (chi(2) = 12.17; g.l. = 4), with infection more frequent between 18 and 27 years. In 71.02% of the cases, B. hominis was the only parasite. Giardia lamblia was the parasite most frequently associated with B. hominis (2.41%). In the majority (85%) of infected individuals, less than five microorganisms per microscopic field were observed. We conclude that B. hominis is a frequent intestinal parasite among food handlers in Caroní Municipality, Bolivar State, Venezuela.

Adolescent↗
PubMed2001

[Low impact of silent hepatitis B virus infection on the incidence of post-transfusion hepatitis in Venezuela].

OBJECTIVE: Silent infection by hepatitis B virus (HBV) occurs in the absence of serological markers for the virus. This type of occult infection is generally chronic, asymptomatic, and associated with low levels of viral replication. This study determined the presence of HBV DNA in the sera of blood donors who were negative for serological markers that were tested during screening, with the goal of evaluating the impact of silent HBV infection in posttransfusion hepatitis B in Venezuela. METHODS: A total of 2,075 sera were tested in 53 serum pools of 25-50 donations (0.5-1.0 mL from each sample). The pools were subjected to ultracentrifugation prior to DNA extraction by the proteinase K, phenol/chloroform method. RESULTS: No HBV DNA was found in any of the pools by nested polymerase chain reaction, using primers for highly conserved regions of the genes that code for the surface antigen and for the viral capsid. Aminotransferase levels were normal in 98% of 200 sera that were tested. CONCLUSIONS: These results suggest that there is a low risk of acquiring posttransfusion hepatitis B in Venezuela.

Adolescent↗
PubMed2004

[Morphologic identification of Ehrlichia sp. in the platelets of patients infected with the human immunodeficiency virus in Venezuela].

OBJECTIVE: To determine the frequency of infection by bacteria of the genus Ehrlichia in a population of patients infected with the human immunodeficiency virus (HIV). As is widely recognized, HIV infection is usually followed by the acquired immunodeficiency syndrome (AIDS) after a variable period during which the individual can develop different types of opportunistic infections whose severity depends on his/her immune status. Human ehrlichiosis is a newly-recognized tick-borne infectious disease caused by Ehrlichia spp., which are obligate intracellular, Gram-negative bacteria showing tropism for blood cells (leukocytes and platelets). In Venezuela, the disease was first recognized in humans in 1994, when intra-cytoplasmic microcolonies (morula) were found in human platelets. METHODS: We collected peripheral blood samples from 87 HIV-positive persons that were received at the Immunology Laboratory of the Oncology and Hematology Institute in Caracas, Venezuela, one of the country's referral centers for cases of HIV infection. Slides prepared from buffy coat that had been stained with Wright's solution and sealed with resin for preservation were examined retrospectively under the light microscope. RESULTS: Ehrlichia spp. were found in the platelets of 12 of the 87 (13.8%) patients whose slides were examined. CONCLUSION: The presence of Ehrlichia sp. in the platelets of HIV-positive patients suggests that ehrlichiosis should be among the differential diagnoses of opportunistic infection in this group of patients.

AIDS-Related Opportunistic Infections↗
PubMed2000

Factors associated with distribution of Anopheles aquasalis and Anopheles oswaldoi (Diptera: Culicidae) in a malarious area, northeastern Venezuela.

Spatial and temporal abundance patterns of anopheline larvae and their relationships with wetland conditions were studied in an endemic malaria area in northeastern Venezuela, where Anopheles aquasalis Curry is the main vector. Larvae were sampled over a 2-yr period in 7 wetland types (brackish and freshwater herbaceous swamps, mangrove swamps, freshwater ponds, clear-cut marsh forests, small irrigation canals, and swamp forests), covering 3 environmental gradients (salinity, aquatic vegetation, and habitat permanence). Twelve variable were quantified to describe each habitat. Two species of anophelines were collected. An. aquasalis was the species with the widest distribution, and its highest abundance was in the seasonal brackish mangrove habitat during the rainy season. An. oswaldoi Peryassu was rarely encountered, but was mainly associated with the dry season and with the permanent fresh water wetlands (such as ponds). Principal components and correlation analyses revealed that the physicochemical (salinity, dissolved oxygen) variables of the wetland were associated most strongly with the spatial distribution of both species. Variations in salinity were strongly associated with the abundance of An. aquasalis. Both the occurrence and abundance of An. oswaldoi were most closely correlated with dissolved oxygen. Changes in seasonal abundance of both species were associated with rainfall. The relevance of these results to vector control in northern Venezuela is discussed.

Animals↗
PubMed2001

Detection of insecticide resistance in Aedes aegypti (Diptera: Culicidae) from Cuba and Venezuela.

Four strains of Aedes aegypti (L.), one from Cuba and three from Venezuela, were bioassayed for susceptibility to eight insecticides, including the organophosphates, temephos, malathion, fenthion, pirimiphos methyl, and chlorpyrifos, and the pyrethroids, deltamethrin, lambda cyhalothrin and cypermethrin, S, S, S,-tributyl phosphorotrithioate and piperonyl butoxide were used as synergists to assess the involvement of esterases and monooxygenases in organophosphate resistance. Venezuelan strains had low levels of resistance to fenthion and malathion, and moderate to high resistance to temephos, pyrimphos methyl, and chlorpiriphos. All strains were susceptible to the pyrethroids, except the Cuban strain, which had moderate levels of resistance to cypermethrin. Organophosphate resistance in Ae. aegypti is a serious threat to control operations. Integrated strategies for Ae. aegypti control to prevent or delay pyrethroid resistance in Venezuela and Cuba are discussed.

Aedes↗
PubMed2005

Toxoplasma gondii infections in chickens from Venezuela: isolation, tissue distribution, and molecular characterization.

The prevalence of Toxoplasma gondii, in free-ranging chickens is a good indicator of the prevalence of T. gondii oocysts in the soil because chickens feed from the ground. The prevalence of T. gondii in 46 free-range chickens (Gallus domesticus) from Venezuela was determined. Antibodies to T. gondii were assayed by the modified agglutination test (MAT). Antibodies were found in 16 (32%) chickens with titers of 1:5 in 1, 1:10 in 2, 1:40 in 2, 1:80 in 2, 1:160 in 2, 1:320 in 3, 1: 640 in 2, and 1:1,280 or higher in 2. Hearts, pectoral muscles, and brains of 13 chickens with MAT titers of 1:40 or more were bioassayed individually in mice. Tissues of each of 3 chickens with titers of 1:5 or 1:10 were pooled and bioassayed in mice. Tissues from the remaining 30 seronegative chickens were pooled and fed to 1 T. gondii-free cat. Feces of the cat were examined for oocysts; it did not shed oocysts. Toxoplasma gondii was isolated from 12 of 13 chickens with MAT titers of 1:40 or more. Toxoplasma gondii was isolated from pooled tissues of 1 of 2 chickens with titers of 1:10. Eight of these 13 isolates were virulent for mice. Genotyping of 13 of these isolates using the SAG2 locus indicated that 10 were type III, and 3 were type II. Phenotypically and genetically these isolates were different from T. gondii isolates from North America and Brazil. This is the first report of isolation of T. gondii from chickens from Venezuela.

Agglutination Tests↗
PubMed2004

An alternative to the neoliberal model in health: the case of Venezuela.

The authors present a synthesis of the proposals put forth by the health sector of Venezuela during the framing of the new Venezuelan Constitution. They summarize the background to the National Constituent Assembly and the legal framework typical of the health sector at that time, identify the methodological aspects that substantiated the health topics included in the new Constitution, and analyze the articles that shape the current constitutional health framework in Venezuela, summarizing their most important features and comparing them with neoliberal health proposals.

Health Care Reform↗
PubMed2004

Family cluster of Mayaro fever, Venezuela.

A cluster of protracted migratory polyarthritis involving four adult family members occurred in January 2000 after a brief overnight outing in a rural area of Venezuela. Laboratory testing demonstrated Mayaro virus as the cause of the cluster. These results documented the first human cases of Mayaro virus in Venezuela.

Adult↗
PubMed1998

Giant toads Bufo marinus in Australia and Venezuela have antibodies against 'ranaviruses'.

A serological survey was conducted for antibodies against 'ranaviruses' in the giant toad Bufo marinus in Australia and Venezuela. Sera containing antibodies against 'ranaviruses' were found in both countries. In Australia positive antibodies were identified in populations throughout most of the known range of B. marinus. Results were confirmed by immunofluorescence and immunoelectron microscopy where a characteristic staining pattern of 'ranaviruses' in infected cells was observed. Whilst a 'ranavirus(es)' has been isolated from populations of B. marinus in Venezuela, no virus has been isolated from Australian B. marinus populations. The significance of 'ranavirus' sero-positive B. marinus in Australia is discussed.

Animals↗
PubMed1985

A field study of paragonimiasis in Venezuela.

In a natural focus of paragonimiasis in the northeastern region of Venezuela, 130 people were clinically, parasitologically and immunologically evaluated. A specific intradermal test was positive in 13%. Besides an index case, three other active cases of paragonimiasis were identified. Adult Paragonimus worms and metacercariae were recovered from Didelphis marsupialis and Eudaniela garmani, respectively. Previous reports of Paragonimus infection in Venezuela are discussed.

Adolescent↗