Overview of latest articles and publications on ebola in PubMed. PubMed is a service of the US National Library of Medicine that includes over 18 million citations from MEDLINE and other life science journals.
- Correction: Spread of the Invasive Mosquitoes Aedes aegypti and Aedes albopictus in the Black Sea Region Increases Risk of Chikungunya, Dengue, and Zika Outbreaks in Europe.
Akiner MM, Demirci B, Babuadze G, et al. Correction: Spread of the Invasive Mosquitoes Aedes aegypti and Aedes albopictus in the Black Sea Region Increases Risk of Chikungunya, Dengue, and Zika Outbreaks in Europe. [PUBLISHED ERRATUM]PLoS Negl Trop Dis 2016 May; 10(5):e0004764.[This corrects the article DOI: 10.1371/journal.pntd.0004664.].
- First Case of Zika Virus Infection in a HIV+ Patient.
Barreiro P First Case of Zika Virus Infection in a HIV+ Patient. [JOURNAL ARTICLE]AIDS Rev 2016 Apr-Jun; 18(2):112.Zika virus is an enveloped, single-stranded RNA virus that belongs to the flavivirus genre. As with arbovirus, it is transmitted by arthropods (mosquitoes), both Aedes aegypti (urban) and albopictus (rural). Zika virus was first isolated in 1947 from monkeys in Uganda. The first human cases were reported in 1952 in East Africa. Outbreaks were reported in Micronesia (2007), Polynesia (2013), and Chile (2014). Both diagnostic procedures and therapeutics are poorly developed. Serological tests cross-react with dengue and there are neither specific antivirals nor vaccines.
- Effects of temperature on the life cycle, expansion, and dispersion of Aedes aegypti (Diptera: Culicidae) in three cities in Paraiba, Brazil.
Marinho RA, Beserra EB, Bezerra-Gusmão MA, et al. Effects of temperature on the life cycle, expansion, and dispersion of Aedes aegypti (Diptera: Culicidae) in three cities in Paraiba, Brazil. [Journal Article]J Vector Ecol 2016 Jun; 41(1):1-10.The mosquito Aedes aegypti is the primary vector of dengue and is common throughout tropical and subtropical regions. Its distribution is modulated by environmental factors, such as temperature. This study aimed to evaluate the influence of temperature on the life cycle and expansion of Ae. aegypti populations in the cities of Campina Grande, João Pessoa, and Patos. Samples of Ae. aegypti were collected in the three cities and raised in the laboratory. We assessed the life cycles of the three Ae. aegypti populations under six constant temperatures (16, 22, 28, 33, 36, and 39°C), selected on the basis of historical temperature tendencies of each city. We also used existing climate data to calculate projected temperature increases for all three areas. Our results suggest that Campina Grande, João Pessoa, and Patos will experience, respectively, maximum temperature increases of 0.030°C/year, 0.069°C/year, and 0.061°C/year, and minimum temperature increases of 0.019°C/year, -0.047°C/year, and -0.086°C/year. These projected increases will result in temperatures favorable to the Ae. aegypti life cycle, causing rapid population growth. Therefore, Ae. aegypti populations are likely to expand in the mesoregions represented by these cities.
- Hajj-associated infections.
Salmon-Rousseau A, Piednoir E, Cattoir V, et al. Hajj-associated infections. [REVIEW, JOURNAL ARTICLE]Med Mal Infect 2016 May 24.The Hajj is the largest annual mass gathering event in the world, thus favoring the transmission of various infections: 183 different nationalities, high temperatures, coincidence with the start of the flu season in the Northern hemisphere, a long barefoot walk, tent-type accommodation, communal toilet facilities, absence of food control, and sharing of razors. Infections are the first cause of hospital admission, which often occurs in the home country of pilgrims.Literature review on PubMed from 1952 to November 2015 on the epidemiology and prevention of infections contracted during the Hajj, using the keywords "Hajj" and "infections".Respiratory tract infections, ENT infections, influenza, pyogenic pneumonia, whooping cough, and tuberculosis are most frequently observed during the Hajj. Outbreaks of meningococcal meningitis have been reported in pilgrims and their contacts. Waterborne infections such as gastroenteritis and hepatitis A are common, despite the improvement of health conditions. Pyoderma and furuncles are also frequently observed. Recently, dengue fever, Alkhumra hemorrhagic fever, and Rift Valley fever have emerged but no case of MERS-coronavirus, appeared in Saudi Arabia in 2012, have yet been observed during the 2012-2014 Hajj.Prevention is based on compulsory meningococcal vaccination, vaccination against seasonal influenza and pneumococcal infections for pilgrims at high risk of contracting the infection, and on vaccination against hepatitis A. Updating immunization for diphtheria/tetanus/poliomyelitis/pertussis and measles/mumps is also crucial and pilgrims must comply with hygiene precautions.
- Association of microvascular function and endothelial biomarkers with clinical outcome in dengue: an observational study.
Yacoub S, Lam PK, Vu LH, et al. Association of microvascular function and endothelial biomarkers with clinical outcome in dengue: an observational study. [JOURNAL ARTICLE]J Infect Dis 2016 May 26. The hallmark of severe dengue is increased microvascular permeability however alterations in the microcirculation and their evolution over the course of dengue are unknown. We conducted a prospective observational study to evaluate the sublingual microcirculation using sidestream dark field imaging in patients presenting early (<72 hours fever) and patients hospitalized with warning signs or severe dengue in Vietnam. Clinical, microvascular function, global haemodynamics assessed by echocardiograms and serological markers of endothelial activation were performed at 4 time points. 165 patients were enrolled. No difference was found between the microcirculatory parameters comparing dengue with other febrile illnesses. Proportion of perfused vessels (PPV) and Mean Flow Index (MFI) were lower in dengue patients with plasma leakage (PPV: 88.1% vs. 90.6%, P=0.010 and MFI: 2.1 vs. 2.4, P=0.007) most marked during the critical phase. PPV and MFI correlated with the endothelial activation markers, VCAM-1 (P<0.001 for both) and Angiopoietin-2 (P<0.001 and P=0.001 respectively) with a negative association. Modest microcirculatory alterations occur in dengue, are associated with plasma leakage and correlate with molecules of endothelial activation, Angiopoietin-2 and VCAM-1.
- Two different dengue virus strains in the Japanese epidemics of 2014.
Nakayama E, Kotaki A, Tajima S, et al. Two different dengue virus strains in the Japanese epidemics of 2014. [JOURNAL ARTICLE]Virus Genes 2016 May 26.In late August 2014, dengue cases were reported in Japan, and a total of 162 cases were confirmed. In the present study, the envelope (E) gene sequences of 12 specimens from the dengue patients were determined. A dengue virus serotype 1 (DENV1) strain (D1/Hu/Shizuoka/NIID181/2014), which was clearly different from the first reported strain (D1/Hu/Saitama/NIID100/2014), was identified, although the other 11 specimens showed the same nucleotide sequences as D1/Hu/Saitama/NIID100/2014. The E gene sequences of two different strains were compared with those of nine DENV1 strains of imported cases in Japan in 2014. Phylogenetic analysis based on the E gene sequences showed that the D1/Hu/Saitama/NIID100/2014 strain was closely related to a strain isolated from an imported case from Singapore. Although no strain closely related to D1/Hu/Shizuoka/NIID181/2014 was found in these imported strains, the strain was closely related to isolates in Thailand and Taiwan in 2009. These data indicate that the dengue cases in Japan were caused by two different dengue virus strains that entered Japan through different means.
- Association of Polymorphisms in IL1β -511C>T, IL1RN 86 bp VNTR, and IL6 -174G>C Genes with Clinical Dengue Signs and Symptoms in Brazilian Dengue Patients.
Cansanção IF, Carmo AP, Leite RD, et al. Association of Polymorphisms in IL1β -511C>T, IL1RN 86 bp VNTR, and IL6 -174G>C Genes with Clinical Dengue Signs and Symptoms in Brazilian Dengue Patients. [JOURNAL ARTICLE]Viral Immunol 2016 May 26.Dengue is an important infectious disease that has high morbidity and mortality rates in most tropical and subtropical areas of the world. The diversity of the clinical manifestations involved in the outcome of dengue virus infection is affected by the relationship between serotype/genotype of the virus, host immune status, host genetic background, and environmental factors. Polymorphisms in interleukin (IL) genes have been associated with risk of developing symptomatic dengue. This study aimed to determine the association of the single-nucleotide polymorphisms of IL1β -511C>T, IL1RN 86 bp VNTR, and IL6 -174G>C genes with the clinical features of 198 individuals admitted to the São José Infectious Diseases Hospital with suspected dengue infection. Dengue was confirmed in 118 of the patients. The control group consisted of 80 other individuals who had symptoms similar to dengue, but negative for that. A higher frequency of increased hematocrit (p = 0.009), leukopenia (p = 0.000007), neutropenia (p = 0.0004), lymphocytosis (p = 0.00001), monocytosis (p = 0.004), atypical lymphocytes (p = 0.03), and thrombocytopenia (p = 0.0000009) was observed in the dengue patients. Among the polymorphisms studied, only IL1β (-511C>T) was associated with dizziness, (p = 0.01), suggesting that IL1β may be related to hypotensive episodes and increased vascular permeability. These results pointed out the importance of the IL1β (-511C>T) polymorphism in the development of clinical symptoms of dengue symptomology.
- Projected Impact of Dengue Vaccination in Yucatán, Mexico.
Hladish TJ, Pearson CA, Chao DL, et al. Projected Impact of Dengue Vaccination in Yucatán, Mexico. [Journal Article]PLoS Negl Trop Dis 2016 May; 10(5):e0004661.Dengue vaccines will soon provide a new tool for reducing dengue disease, but the effectiveness of widespread vaccination campaigns has not yet been determined. We developed an agent-based dengue model representing movement of and transmission dynamics among people and mosquitoes in Yucatán, Mexico, and simulated various vaccine scenarios to evaluate effectiveness under those conditions. This model includes detailed spatial representation of the Yucatán population, including the location and movement of 1.8 million people between 375,000 households and 100,000 workplaces and schools. Where possible, we designed the model to use data sources with international coverage, to simplify re-parameterization for other regions. The simulation and analysis integrate 35 years of mild and severe case data (including dengue serotype when available), results of a seroprevalence survey, satellite imagery, and climatological, census, and economic data. To fit model parameters that are not directly informed by available data, such as disease reporting rates and dengue transmission parameters, we developed a parameter estimation toolkit called AbcSmc, which we have made publicly available. After fitting the simulation model to dengue case data, we forecasted transmission and assessed the relative effectiveness of several vaccination strategies over a 20 year period. Vaccine efficacy is based on phase III trial results for the Sanofi-Pasteur vaccine, Dengvaxia. We consider routine vaccination of 2, 9, or 16 year-olds, with and without a one-time catch-up campaign to age 30. Because the durability of Dengvaxia is not yet established, we consider hypothetical vaccines that confer either durable or waning immunity, and we evaluate the use of booster doses to counter waning. We find that plausible vaccination scenarios with a durable vaccine reduce annual dengue incidence by as much as 80% within five years. However, if vaccine efficacy wanes after administration, we find that there can be years with larger epidemics than would occur without any vaccination, and that vaccine booster doses are necessary to prevent this outcome.
- Quantifying the Epidemiological Impact of Vector Control on Dengue.
Reiner RC, Achee N, Barrera R, et al. Quantifying the Epidemiological Impact of Vector Control on Dengue. [Journal Article]PLoS Negl Trop Dis 2016 May; 10(5):e0004588.