South-to-north migration preceded the advent of intensive farming in the Maya region.

The genetic prehistory of human populations in Central America is largely unexplored leaving an important gap in our knowledge of the global expansion of humans. We report genome-wide ancient DNA data for a transect of twenty individuals from two Belize rock-shelters dating between 9,600-3,700 calibrated radiocarbon years before present (cal. BP). The oldest individuals (9,600-7,300 cal. BP) descend from an Early Holocene Native American lineage with only distant relatedness to present-day Mesoamericans, including Mayan-speaking populations. After ~5,600 cal. BP a previously unknown human dispersal from the south made a major demographic impact on the region, contributing more than 50% of the ancestry of all later individuals. This new ancestry derived from a source related to present-day Chibchan speakers living from Costa Rica to Colombia. Its arrival corresponds to the first clear evidence for forest clearing and maize horticulture in what later became the Maya region.

Exploring convolutional neural networks and spatial video for on-the-ground mapping in informal settlements.

BACKGROUND: The health burden in developing world informal settlements often coincides with a lack of spatial data that could be used to guide intervention strategies. Spatial video (SV) has proven to be a useful tool to collect environmental and social data at a granular scale, though the effort required to turn these spatially encoded video frames into maps limits sustainability and scalability. In this paper we explore the use of convolution neural networks (CNN) to solve this problem by automatically identifying disease related environmental risks in a series of SV collected from Haiti. Our objective is to determine the potential of machine learning in health risk mapping for these environments by assessing the challenges faced in adequately training the required classification models. RESULTS: We show that SV can be a suitable source for automatically identifying and extracting health risk features using machine learning. While well-defined objects such as drains, buckets, tires and animals can be efficiently classified, more amorphous masses such as trash or standing water are difficult to classify. Our results further show that variations in the number of image frames selected, the image resolution, and combinations of these can be used to improve the overall model performance. CONCLUSION: Machine learning in combination with spatial video can be used to automatically identify environmental risks associated with common health problems in informal settlements, though there are likely to be variations in the type of data needed for training based on location. Success based on the risk type being identified are also likely to vary geographically. However, we are confident in identifying a series of best practices for data collection, model training and performance in these settings. We also discuss the next step of testing these findings in other environments, and how adding in the simultaneously collected geographic data could be used to create an automatic health risk mapping tool.

Isolation of Mayaro Virus from a Venezuelan Patient with Febrile Illness, Arthralgias, and Rash: Further Evidence of Regional Strain Circulation and Possible Long-Term Endemicity.

Fifty-two febrile patients living in Barquisimeto, Venezuela, were screened for arbovirus infection by virus culture during an outbreak of what was thought to be Zika virus infection. We report identification of Mayaro virus (MAYV) on culture of plasma from one patient, an 18-year-old woman with acute febrile illness, arthralgias, and psoriasiform rash. The strain was sequenced and was found to be most closely related to a 1999 strain from French Guiana, which, in turn, was related to two 2014 strains from Haiti. By contrast, previously reported outbreak-related MAYV strains from a sylvatic area approximately 80 miles from where the case patient lived were most closely related to Peruvian isolates. The two strain groups show evidence of having diverged genetically approximately 100 years ago.

Micro-Space Complexity and Context in the Space-Time Variation in Enteric Disease Risk for Three Informal Settlements of Port au Prince, Haiti.

Diffusion of cholera and other diarrheal diseases in an informal settlement is a product of multiple behavioral, environmental and spatial risk factors. One of the most important components is the spatial interconnections among water points, drainage ditches, toilets and the intervening environment. This risk is also longitudinal and variable as water points fluctuate in relation to bacterial contamination. In this paper we consider part of this micro space complexity for three informal settlements in Port au Prince, Haiti. We expand on more typical epidemiological analysis of fecal coliforms at water points, drainage ditches and ocean sites by considering the importance of single point location fluctuation coupled with recording micro-space environmental conditions around each sample site. Results show that spatial variation in enteric disease risk occurs within neighborhoods, and that while certain trends are evident, the degree of individual site fluctuation should question the utility of both cross-sectional and more aggregate analysis. Various factors increase the counts of fecal coliform present, including the type of water point, how water was stored at that water point, and the proximity of the water point to local drainage. Some locations fluctuated considerably between being safe and unsafe on a monthly basis. Next steps to form a more comprehensive contextualized understanding of enteric disease risk in these environments should include the addition of behavioral factors and local insight.

Acute Respiratory Illness in Rural Haiti.

OBJECTIVES: Acute Respiratory Infection (ARI) is the most common cause of childhood morbidity and mortality in developing countries, including Haiti. Our objective was to detect pathogens found in children with ARI in rural Haiti to help develop evidence-based guidelines for treatment and prevention. METHODS: Retrospective study of students with ARI at four schools in rural Haiti. Viral and/or bacterial pathogens were identified by qPCR in 177 nasal swabs collected from April 2013 through November 2015. RESULTS: Most common viruses detected were Rhinovirus (36%), Influenza A (16%) and Adenovirus (7%), and bacteria were Streptococcus pneumoniae (58%) and Staphylococcus aureus (28%). Compared to older children, children aged 3-5 years had more Influenza A (28% vs. 9%, p=0.002) and Adenovirus detected (14% vs. 3%, p=0.01). Similarly, S. pneumoniae was greatest in children 3-5 years old (71% 3-5yrs; 58% 6-15 years; 25% 16-20 years; p=0.008). Children 3-10 years old presented with fever more than children 11-20 years old (22% vs 7%; p=0.02) and were more often diagnosed with pneumonia (28% vs 4%, p<0.001). CONCLUSIONS: Younger children had increased fever, pneumonia, and detection of Influenza A and S. pneumoniae. These data support the need for influenza and pneumococcus vaccination in early childhood in Haiti.

A new "American" subgroup of African-lineage Chikungunya virus detected in and isolated from mosquitoes collected in Haiti, 2016.

As part of on-going arboviral surveillance activity in a semi-rural region in Haiti, Chikungunya virus (CHIKV)-positive mosquito pools were identified in 2014 (the peak of the Caribbean Asian-clade epidemic), and again in 2016 by RT-PCR. In 2014, CHIKV was only identified in Aedes aegypti (11 positive pools/124 screened). In contrast, in sampling in 2016, CHIKV was not identified in Ae. aegypti, but, rather, in (a) a female Aedes albopictus pool, and (b) a female Culex quinquefasciatus pool. Genomic sequence analyses indicated that the CHIKV viruses in the 2016 mosquito pools were from the East-Central-South African (ECSA) lineage, rather than the Asian lineage. In phylogenetic studies, these ECSA lineage strains form a new ECSA subgroup (subgroup IIa) together with Brazilian ECSA lineage strains from an isolated human outbreak in 2014, and a mosquito pool in 2016. Additional analyses date the most recent common ancestor of the ECSA IIa subgroup around May 2007, and the 2016 Haitian CHIKV genomes around December 2015. Known CHIKV mutations associated with improved Ae. albopictus vector competence were not identified. Isolation of this newly identified lineage from Ae. albopictus is of concern, as this vector has a broader geographic range than Ae. aegypti, especially in temperate areas of North America, and stresses the importance for continued vector surveillance.

Socioeconomic Vulnerability and Sexually Transmitted Infection Among Pregnant Haitian Women.

BACKGROUND: Despite evidence that education and poverty act through distinct pathways to influence sexually transmitted infection (STI), few studies have examined the unique, independent associations of these socioeconomic vulnerabilities with sexual risk behaviors and STI among women. METHODS: From August to October 2013, women at an antenatal clinic in Gressier, Haiti, were interviewed and tested for chlamydial infection, gonorrhea, and trichomoniasis (N = 200). We measured low educational attainment as less than 9 years of schooling and currently living in poverty based on crowding, defined as more than 2 people sleeping in one room. We used logistic regression to estimate independent associations between each socioeconomic indicator and outcomes of sexual behaviors and STI. RESULTS: Approximately 29% of the sample had a current STI (chlamydia, 8.0%; gonorrhea, 3.0%; trichomoniasis, 20.5%), with 2.5% testing positive for more than 1 STI. Forty percent of the sample reported low educational attainment and 40% reported current poverty. Low educational attainment was associated with early risk behaviors, including twice the odds of earlier sexual debut (adjusted odds ratio [AOR], 2.09; 95% confidence interval [CI],: 1.14-3.84). Poverty was associated with reporting the current main sexual partner to be nonmonogamous (AOR, 2.01; 95% CI, 1.00-4.01) and current STI (AOR, 2.50; 95% CI, 1.26-4.98). CONCLUSIONS: Education and poverty seem to independently influence STI behaviors and infection, with low education associated with early sexual risk and poverty associated with current risk and infection. Improving women's educational attainment may be important in improving risk awareness, thereby reducing risky sexual behaviors and preventing a trajectory of STI risk.

Detection of Alphacoronavirus vRNA in the Feces of Brazilian Free-Tailed Bats (Tadarida brasiliensis) from a Colony in Florida, USA.

Bats are natural reservoirs of coronaviruses and other viruses with zoonotic potential. Florida has indigenous non-migratory populations of Brazilian free-tailed bats (Tadarida brasiliensis) that mostly roost in colonies in artificial structures. Unlike their counterparts in Brazil and Mexico, the viruses harbored by the Florida bats have been underexplored. We report the detection of an alphacoronavirus RNA-dependent RNA polymerase (RdRp) gene sequence in the feces of two of 19 different T. brasiliensis that were capture/release bats that had been evaluated for overall health. The RdRp sequence is similar but not identical to previously detected sequences in the feces of two different species of bats (T. brasiliensis and Molossus molossus) in Brazil. In common with the experience of others doing similar work, attempts to isolate the virus in cell cultures were unsuccessful. We surmise that this and highly related alphacoronavirus are carried by Brazilian free-tailed bats living in a wide eco-spatial region. As various coronaviruses (CoVs) that affect humans emerged from bats, our study raises the question whether CoVs such as the one detected in our work are yet-to-be-detected pathogens of humans and animals other than bats.

Controlling cholera in the Ouest Department of Haiti using oral vaccines.

Following the 2010 cholera outbreak in Haiti, a plan was initiated to provide massive improvements to the sanitation and drinking water infrastructure in order to eliminate cholera from the island of Hispaniola by 2023. Six years and a half billion dollars later, there is little evidence that any substantial improvements have been implemented; with increasing evidence that cholera has become endemic. Thus, it is time to explore strategies to control cholera in Haiti using oral cholera vaccines (OCVs). The potential effects of mass administration of OCVs on cholera transmission were assessed using dynamic compartment models fit to cholera incidence data from the Ouest Department of Haiti. The results indicated that interventions using an OCV that was 60% effective could have eliminated cholera transmission by August 2012 if started five weeks after the initial outbreak. A range of analyses on the ability of OCV interventions started January 1, 2017 to eliminate cholera transmission by 2023 were performed by considering different combinations of vaccine efficacies, vaccine administration rates, and durations of protective immunity. With an average of 50 weeks for the waiting time to vaccination and an average duration of three years for the vaccine-induced immunity, all campaigns that used an OCV with a vaccine efficacy of at least 60% successfully eliminated cholera transmission by 2023. The results of this study suggest that even with a relatively wide range of vaccine efficacies, administration rates, and durations of protective immunity, future epidemics could be controlled at a relatively low cost using mass administration of OCVs in Haiti.

Increased isolation frequency of toxigenic Vibrio cholerae O1 from environmental monitoring sites in Haiti.

Since the identification of the first cholera case in 2010, the disease has spread in epidemic form throughout the island nation of Haiti; as of 2014, about 700,000 cholera cases have been reported, with over 8,000 deaths. While case numbers have declined, the more fundamental question of whether the causative bacterium, Vibrio cholerae has established an environmental reservoir in the surface waters of Haiti remains to be elucidated. In a previous study conducted between April 2012 and March 2013, we reported the isolation of toxigenic V. cholerae O1 from surface waters in the Ouest Department. After a second year of surveillance (April 2013 to March 2014) using identical methodology, we observed a more than five-fold increase in the number of water samples containing culturable V. cholerae O1 compared to the previous year (1.7% vs 8.6%), with double the number of sites having at least one positive sample (58% vs 20%). Both seasonal water temperatures and precipitation were significantly related to the frequency of isolation. Our data suggest that toxigenic V. cholerae O1 are becoming more common in surface waters in Haiti; while the basis for this increase is uncertain, our findings raise concerns that environmental reservoirs are being established.

Protein network prediction and topological analysis in Leishmania major as a tool for drug target selection.

BACKGROUND: Leishmaniasis is a virulent parasitic infection that causes a worldwide disease burden. Most treatments have toxic side-effects and efficacy has decreased due to the emergence of resistant strains. The outlook is worsened by the absence of promising drug targets for this disease. We have taken a computational approach to the detection of new drug targets, which may become an effective strategy for the discovery of new drugs for this tropical disease. RESULTS: We have predicted the protein interaction network of Leishmania major by using three validated methods: PSIMAP, PEIMAP, and iPfam. Combining the results from these methods, we calculated a high confidence network (confidence score > 0.70) with 1,366 nodes and 33,861 interactions. We were able to predict the biological process for 263 interacting proteins by doing enrichment analysis of the clusters detected. Analyzing the topology of the network with metrics such as connectivity and betweenness centrality, we detected 142 potential drug targets after homology filtering with the human proteome. Further experiments can be done to validate these targets. CONCLUSION: We have constructed the first protein interaction network of the Leishmania major parasite by using a computational approach. The topological analysis of the protein network enabled us to identify a set of candidate proteins that may be both (1) essential for parasite survival and (2) without human orthologs. These potential targets are promising for further experimental validation. This strategy, if validated, may augment established drug discovery methodologies, for this and possibly other tropical diseases, with a relatively low additional investment of time and resources.

Lateral gene transfer of O1 serogroup encoding genes of Vibrio cholerae.

In Gram-negative bacteria, the O-antigen-encoding genes may be transferred between lineages, although mechanisms are not fully understood. To assess possible lateral gene transfer (LGT), 21 Argentinean Vibrio cholerae O-group 1 (O1) isolates were examined using multilocus sequence typing (MLST) to determine the genetic relatedness of housekeeping genes and genes from the O1 gene cluster. MSLT analysis revealed that 4.4% of the nucleotides in the seven housekeeping loci were variable, with six distinct genetic lineages identified among O1 isolates. In contrast, MLST analysis of the eight loci from the O1 serogroup region revealed that 0.24% of the 4943 nucleotides were variable. A putative breakpoint was identified in the JUMPstart sequence. Nine conserved nucleotides differed by a single nucleotide from a DNA uptake signal sequence (USS) also found in Pastuerellaceae. Our data indicate that genes in the O1 biogenesis region are closely related even in distinct genetic lineages, indicative of LGT, with a putative DNA USS identified at the defined boundary for the DNA exchange.

Oxford anatomía funcional: cabeza y cuello / Oxford anatomía funcional / Oxford Functional Anatomy: head and neck

Trata de manera sistemática las caractéristicas estructurales y los movimientos de la cabeza y el cuello y los tractos respiratorio superior y alimentario. Muestran el interior del cráneo, las órbitas, la cara y el cuello, con énfasis en las inervaciones craneales y autónomas. Da referencia del desarrollo del los órganos, muestra imágenes radiográficas y endoscópicas normales y anormales de los mismos

Oxford anatomía funcional: cabeza y cuello / Oxford anatomía funcional / Oxford Functional Anatomy: head and neck

Trata de manera sistemática las caractéristicas estructurales y los movimientos de la cabeza y el cuello y los tractos respiratorio superior y alimentario. Muestran el interior del cráneo, las órbitas, la cara y el cuello, con énfasis en las inervaciones craneales y autónomas. Da referencia del desarrollo del los órganos, muestra imágenes radiográficas y endoscópicas normales y anormales de los mismos