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In this article, a new species of salamander of the genus Bolitoglossa (Eladinea) from the cloud forest near La Mucuy in Sierra Nevada de Mérida, Venezuelan Andes, is described. Bolitoglossa mucuyensis sp. nov. differs from all Venezuelan salamanders, except B. orestes, by a larger SVL/TL ratio, and from La Culata salamander B. orestes by a reduced webbing extension of the front and hind limbs. Additionally, B. mucuyensis sp. nov. and B. orestes diverge 3.12% in terms of the nucleotide sequence of the 16S rRNA gene, as previously reported, and in 8.1% for the cytb gene as shown in this study.

Background: Hospital-based studies to determine the etiology of deaths from diarrhea are scarce. In this study, we specifically analyzed deaths due to rotavirus to assess the rotavirus impact on diarrhea mortality., Methods: To determine the rotavirus proportion contributing to mortality due to diarrhea, we analyzed data obtained from a hospital-based mortality surveillance, conducted over 7 years, in the Ciudad Hospitalaria Dr. Enrique Tejera, Valencia, Venezuela. Rotavirus was identified in stool samples collected from children who died of diarrhea, by a confirmatory ELISA and/or reverse transcription polymerase chain reaction., Results: Our results show that rotavirus (21%; 21/100) is the leading cause of death due to diarrhea among children <5 years of age; rotavirus also has an important impact (2%; 21/1336) on deaths from all causes in this age group. Shigella spp. (19%; 13/69) was the second most important cause of death, followed by calicivirus (6%; 3/53). Furthermore, this study documents a seasonal pattern in the deaths due to rotavirus (odds ratio 3.28; 95% confidence interval 1.13-9.76)., Conclusions: For Venezuela, it is estimated that approximately 300 children <5 years of age die of rotavirus each year, which means that 1 in 1800 children die by the age of 5. Rotavirus was found to be the main cause of death due to diarrhea, which supports previous estimations. This is the first study to present data of cause-specific mortality due to diarrhea based on hospital surveillance of diarrhea etiologies.

We describe the hourly patterns of parous biting activity of the three main simuliid vectors of human onchocerciasis in the Amazonian focus straddling between Venezuela and Brazil, namely, Simulium guianense s.l. Wise; S. incrustatum Lutz, and S. oyapockense s.l. Floch and Abonnenc. Time series of the hourly numbers of host-seeking parous flies caught in five Yanomami villages during dry, rainy, and their transition periods from 1995 to 2001 were investigated using harmonic analysis (assuming an underlying circadian rhythm) and periodic correlation (based on Spearman's r). Parous S guianense s.l. showed a bimodal activity pattern, with a minor peak in mid-morning and a major peak at 16:00 h. S. incrustatum exhibited mainly unimodal activity during either early morning or midday according to locality. S. oyapockense s.l. bit humans throughout the day mainly between 10:00 and 16:00 h but also showed bimodal periodicity in some localities. Superimposed on the endogenous, species-specific daily cycles, parous activity showed variation according to locality, season, air temperature and relative humidity, with biting being promoted by warmer and drier hours during wet seasons/periods and reduced during hotter times in dry seasons or transitions. The results are discussed in terms of their implications for blackfly biology and ecology as well as onchocerciasis epidemiology and control.

Background: To effectively introduce a rotavirus vaccine in developing countries, it is necessary to estimate the burden of rotavirus disease. Therefore we examined the epidemiologic and clinical features of rotavirus diarrhea in children younger than 5 years of age in Carabobo State and extrapolated these results to the rest of Venezuela., Methods: From January 1, 1998 to December 31, 2002, we conducted surveillance for rotavirus diarrhea in all children younger than 5 years of age at the Ciudad Hospitalaria Dr Enrique Tejera, in Valencia (Carabobo)., Results: Rotavirus is the major cause of diarrhea in children younger than 5 years of age in Venezuela, accounting for one-fourth (23%) of all episodes of diarrhea requiring medical treatment and one-third (33%) of those requiring hospitalization. Rotavirus diarrhea was responsible for 3% of all hospitalizations and 2% of all medical visits. In Valencia, rotavirus had a marked seasonal peak during the dry and cold months of the year. Rotavirus was most frequent in children 3-23 months of age, and 61% of the cases occurred by the age of 1 year. In addition, rotavirus diarrhea was more severe in younger children. Overall, by the age of 5 years, 1 child in 72 will be hospitalized and 1 in 24 will visit the clinic for rotavirus disease. In Venezuela, we estimated that each year, 118,000 children experience rotavirus illness requiring medical care and 39,000 children require hospitalization., Conclusions: This study confirms the significant impact of rotavirus disease in Venezuela. Rotavirus vaccines currently in development could diminish the morbidity associated with this common cause of childhood diarrheal disease.

Background: The first licensed rotavirus vaccine was withdrawn from use in the United States because of a low risk of intussusception. Consequently tests of new rotavirus vaccines will require some baseline knowledge of the rates and treatment of intussusception in countries where these vaccines will be tested. Therefore the objective of this study was to assess hospitalization rates and describe the epidemiologic and clinical characteristics of intussusception in Carabobo, Venezuela., Methods: This study reviewed hospital data and clinical records of pediatric patients with intussusception admitted to eight hospitals in Carabobo between January 1, 1998 and December 31, 2001., Results: For the 4-year period the average annual hospitalization rate for intussusception among infants (<1 year old) in Carabobo was 35 per 100 000 infants per year (range, 22 to 44), and intussusception was more common among boys (58 per 100 000 infants per year) than girls (29 per 100 000 infants per year) (P = 0.006). One of 67 cases occurred in the first 3 months of life (0 to 2), 55% (37) patients were 3 to 5 months old, 31% (21) were 6 to 11 months old and 12% (8) were > or =12 months old. Surgical reduction was required in 88% (52 of 59) of infants but only 1 required bowel resection. The monthly distribution of intussusception-associated hospitalizations showed no consistent seasonal pattern with the seasonality observed for patients hospitalized with rotavirus disease., Conclusions: This study provides some data about the incidence of intussusception and its epidemiology in a developing country where current or future field trials with rotavirus vaccine will be conducted.

Objective: To develop a Bayesian hierarchical model for human onchocerciasis with which to explore the factors that influence prevalence of microfilariae in the Amazonian focus of onchocerciasis and predict the probability of any community being at least mesoendemic (>20% prevalence of microfilariae), and thus in need of priority ivermectin treatment., Methods: Models were developed with data from 732 individuals aged > or =15 years who lived in 29 Yanomami communities along four rivers of the south Venezuelan Orinoco basin. The models' abilities to predict prevalences of microfilariae in communities were compared. The deviance information criterion, Bayesian P-values, and residual values were used to select the best model with an approximate cross-validation procedure., Findings: A three-level model that acknowledged clustering of infection within communities performed best, with host age and sex included at the individual level, a river-dependent altitude effect at the community level, and additional clustering of communities along rivers. This model correctly classified 25/29 (86%) villages with respect to their need for priority ivermectin treatment., Conclusion: Bayesian methods are a flexible and useful approach for public health research and control planning. Our model acknowledges the clustering of infection within communities, allows investigation of links between individual- or community-specific characteristics and infection, incorporates additional uncertainty due to missing covariate data, and informs policy decisions by predicting the probability that a new community is at least mesoendemic.