Population Density, Poor Sanitation, and Enteric Infections in Nueva Santa Rosa, Guatemala

Poor sanitation could pose greater risk for enteric pathogen transmission at higher human population densities because of greater potential for pathogens to infect new hosts through environmentally mediated and person-to-person transmission. We hypothesized that incidence and prevalence of diarrhea, enteric protozoans, and soil-transmitted helminth infections would be higher in high-population-density areas compared with low-population-density areas, and that poor sanitation would pose greater risk for these enteric infections at high density compared with low density. We tested our hypotheses using 6 years of clinic-based diarrhea surveillance (2007–2013) including 4,360 geolocated diarrhea cases tested for 13 pathogens and a 2010 cross-sectional survey that measured environmental exposures from 204 households (920 people) and tested 701 stool specimens for enteric parasites. We found that population density was not a key determinant of enteric infection nor a strong effect modifier of risk posed by poor household sanitation in this setting.

Experimentally induced innovations lead to persistent culture via conformity in wild birds

In human societies, cultural norms arise when behaviours are transmitted through social networks via high-fidelity social learning. However, a paucity of experimental studies has meant that there is no comparable understanding of the process by which socially transmitted behaviours might spread and persist in animal populations. Here we show experimental evidence of the establishment of foraging traditions in a wild bird population. We introduced alternative novel foraging techniques into replicated wild sub-populations of great tits (Parus major) and used automated tracking to map the diffusion, establishment and long-term persistence of the seeded innovations. Furthermore, we used social network analysis to examine the social factors that influenced diffusion dynamics. From only two trained birds in each sub-population, the information spread rapidly through social network ties, to reach an average of 75% of individuals, with a total of 414 knowledgeable individuals performing 57,909 solutions over all replicates. The sub-populations were heavily biased towards using the technique that was originally introduced, resulting in established local traditions that were stable over two generations, despite a high population turnover. Finally, we demonstrate a strong effect of social conformity, with individuals disproportionately adopting the most frequent local variant when first acquiring an innovation, and continuing to favour social information over personal information. Cultural conformity is thought to be a key factor in the evolution of complex culture in humans. In providing the first experimental demonstration of conformity in a wild non-primate, and of cultural norms in foraging techniques in any wild animal, our results suggest a much broader taxonomic occurrence of such an apparently complex cultural behaviour.

Civil Surgeon Tuberculosis Evaluations for Foreign-Born Persons Seeking Permanent U.S. Residence

Foreign-born persons in the United States seeking to adjust their status to permanent resident must undergo screening for tuberculosis (TB) disease. Screening is performed by civil surgeons (CS) following technical instructions by the Centers for Disease Control and Prevention. From 2011 to 2012, 1,369 practicing CS in California, Texas, and New England were surveyed to investigate adherence to the instructions. A descriptive analysis was conducted on 907 (66%) respondents. Of 907 respondents, 739 (83%) had read the instructions and 565 (63%) understood that a chest radiograph is required for status adjustors with TB symptoms; however, only 326 (36%) knew that a chest radiograph is required for immunosuppressed status adjustors. When suspecting TB disease, 105 (12%) would neither report nor refer status adjustors to the health department; 91 (10%) would neither start treatment nor refer for TB infection. Most CS followed aspects of the technical instructions; however, educational opportunities are warranted to ensure positive patient outcomes.

Automatic oral fluid-based HIV testing in HIV screening programmes: automatic for the people

OBJECTIVES

UK guidelines recommend routine HIV testing in general clinical settings when the local HIV prevalence is > 0.2%. During pilot programmes evaluating the guidelines, we used laboratory-based testing of oral fluid from patients accepting tests. Samples (n = 3721) were tested manually using the Bio-Rad Genscreen Ultra HIV Ag-Ab test (Bio-Rad Laboratories Ltd, Hemel Hempstead, UK). This was a methodologically robust method, but handling of samples was labour intensive. We performed a validation study to ascertain whether automation of oral fluid HIV testing using the fourth-generation HIV test on the Abbott Architect (Abbott Diagnostics, Maidenhead, UK) platform was possible.

METHODS

Oral fluid was collected from 143 patients (56 known HIV-positive volunteers and 87 others having contemporaneous HIV serological tests) using the Oracol+ device (Malvern Medicals, Worcester, UK). Samples were tested concurrently: manually using the Genscreen Ultra test and automatically on the Abbott Architect.

RESULTS

For oral fluid, the level of agreement of results between the platforms was 100%. All results agreed with HIV serology. The use of the Oracol+ device produced high-quality samples. Subsequent field use of the test has shown a specificity of 99.97% after nearly 3000 tests.

CONCLUSIONS

Laboratory-based HIV testing of oral fluid requires less training of local staff, with fewer demands on clinical time and space than near-patient testing. It is acceptable to patients. The validation exercise and subsequent clinical experience support automation, with test performance preserved. Automation reduces laboratory workload and speeds up the release of results. Automated oral fluid testing is thus a viable option for large-scale HIV screening programmes.

Economic and health impacts associated with a Salmonella Typhimurium drinking water outbreak-Alamosa, CO, 2008

In 2008, a large Salmonella outbreak caused by contamination of the municipal drinking water supply occurred in Alamosa, Colorado. The objectives of this assessment were to determine the full economic costs associated with the outbreak and the long-term health impacts on the community of Alamosa. We conducted a postal survey of City of Alamosa (2008 population: 8,746) households and businesses, and conducted in-depth interviews with local, state, and nongovernmental agencies, and City of Alamosa healthcare facilities and schools to assess the economic and long-term health impacts of the outbreak. Twenty-one percent of household survey respondents (n = 369/1,732) reported diarrheal illness during the outbreak. Of those, 29% (n = 108) reported experiencing potential long-term health consequences. Most households (n = 699/771, 91%) reported municipal water as their main drinking water source at home before the outbreak; afterwards, only 30% (n = 233) drank unfiltered municipal tap water. The outbreak’s estimated total cost to residents and businesses of Alamosa using a Monte Carlo simulation model (10,000 iterations) was approximately $1.5 million dollars (range: $196,677–$6,002,879), and rose to $2.6 million dollars (range: $1,123,471–$7,792,973) with the inclusion of outbreak response costs to local, state and nongovernmental agencies and City of Alamosa healthcare facilities and schools. This investigation documents the significant economic and health impacts associated with waterborne disease outbreaks and highlights the potential for loss of trust in public water systems following such outbreaks.

Minimagnetospheres above the lunar surface and the formation of lunar swirls

In this paper we present in situ satellite data, theory, and laboratory validation that show how small-scale collisionless shocks and minimagnetospheres can form on the electron inertial scale length. The resulting retardation and deflection of the solar wind ions could be responsible for the unusual "lunar swirl" patterns seen on the surface of the Moon.

The heart rate response to nintendo wii boxing in young adults

PURPOSE

To determine if 30 minutes of Nintendo Wii Sports boxing provides cardiorespiratory benefits and contributes to the daily exercise recommendations for healthy young adults.

METHODS

Twenty healthy 23- to 27-year-olds participated in two sessions to measure maximum heart rate (HR(max)) via a treadmill test and heart rate (HR) response to 30 minutes of Wii Sports boxing. Heart rate in beats per minute (bpm) was measured continuously, and exercise intensity during each minute of play was stratified as a percentage of HR(max). Mixed designs analysis of variance (ANOVA) and Pearson product moment correlations were used to analyze the data.

RESULTS

Mean (SD) HR response to boxing was 143 (15) bpm or 77.5% (10.0%) of HR(max). The mean HR response for experienced participants was significantly lower than inexperienced participants, P = .007. The ANOVA revealed a significant interaction between experience and time spent at various intensities, P = .009. Experienced participants spent more time in light to vigorous intensities, inexperienced participants in moderate to very hard intensities. Fitness was not correlated with mean HR response to boxing, P = .49.

CONCLUSION

Thirty minutes of Nintendo Wii Sports boxing provides a moderate to vigorous aerobic response in healthy young adults and can contribute to daily recommendations for physical activity.

Atrial remodeling in obstructive sleep apnea: implications for atrial fibrillation

BACKGROUND

There is a known association between obstructive sleep apnea (OSA) and atrial fibrillation (AF); however, how OSA affects the atrial myocardium is not well described.

OBJECTIVE

To determine whether patients with OSA have an abnormal atrial substrate.

METHODS

Forty patients undergoing ablation of paroxysmal AF and in sinus rhythm (20 with OSA [apnea-hypopnea index ≥ 15] and 20 reference patients with no OSA [apnea-hypopnea index < 15] by polysomnography) were studied. Multipolar catheters were positioned at the lateral right atrium (RA), coronary sinus, crista terminalis, and RA septum to determine the effective refractory period at 5 sites, conduction time along linear catheters at the RA and the coronary sinus, conduction at the crista terminalis, and sinus node function (corrected sinus node recovery time). Biatrial electroanatomic maps were created to determine the voltage, conduction, and distribution of complex electrograms (duration ≥ 50 ms).

RESULTS

The groups had no differences in the prevalence of established risk factors for AF. Patients with OSA had the following compared with those without OSA: no difference in effective refractory period (P = .9), prolonged conduction times along the coronary sinus and RA (P = .02), greater number (P = .003) and duration (P = .03) of complex electrograms along the crista terminalis, longer P-wave duration (P = .01), longer corrected sinus node recovery time (P = .02), lower atrial voltage (RA, P <.001; left atrium, P <.001), slower atrial conduction velocity (RA, P = .001; left atrium, P = .02), and more widespread complex electrograms in both atria (RA, P = .02; left atrium, P = .01).

CONCLUSION

OSA is associated with significant atrial remodeling characterized by atrial enlargement, reduction in voltage, site-specific and widespread conduction abnormalities, and longer sinus node recovery. These features may in part explain the association between OSA and AF.

Which women default from follow-up cervical cytology tests? A cohort study within the TOMBOLA trial

OBJECTIVE

To identify factors associated with default from follow-up cervical cytology tests.

METHODS

A cohort study was conducted involving 2166 women, aged 20-59, with recent low-grade cervical cytology taken within the NHS Cervical Screening Programmes in Scotland and England, and managed by 6-monthly cytology in primary care. For the first (6-month) and second (12-month) surveillance cytology tests separately, women were categorized as 'on-time attendees' (attended ≤6 months of test being due), 'late attendees' (attended greater than 6 months after test was due) or 'non-attendees' (failed to attend). Multivariate odds ratios (ORs) were computed for factors associated with late and non-attendance.

RESULTS

For the first surveillance test, risk of non-attendance was significantly higher in younger women, those without post-secondary education, and non-users of prescribed contraception. Factors significantly associated with late attendance for the first test were the same as for non-attendance, plus current smoking and having children. The most important predictor of non-attendance for the second surveillance test was late attendance for the first test (OR = 9.65; 95% CI, 6.60-16.62). Non-attendance for the second test was also significantly higher among women who were younger, smokers and had negative cytology on the first surveillance test. Late attendance for the second surveillance test was higher in women who were younger, smokers, had children and attended late for the first test.

CONCLUSIONS

Women at highest risk of default from follow-up cytology tend to be young, smoke, lack post-secondary education, and have defaulted from a previous surveillance appointment. Tackling default will require development of targeted strategies to encourage attendance and research to better understand the reasons underpinning default.

Long-term psychosocial impact of alternative management policies in women with low-grade abnormal cervical cytology referred for colposcopy: a randomised controlled trial

BACKGROUND

The debate continues regarding the best management for women with low-grade abnormal cervical cytology attending colposcopy. We compared psychosocial outcomes of alternative management policies in these women.

METHODS

In all, 989 women, aged 20-59 years, with low-grade abnormal cytology, were randomised to immediate large loop excision (LLETZ) or two to four targeted punch biopsies taken immediately with recall for LLETZ if these showed cervical intra-epithelial neoplasia 2/3. At 6 weeks after the last procedure, women completed the hospital anxiety and depression scale (HADS) and the impact of event scale (IES). At 12, 18, 24 and 30 months post recruitment, women completed the HADS and process outcome specific measure (POSM). Prevalence of significant depression (≥ 8), significant anxiety (≥ 11) and distress (≥ 9) and median POSM scores were compared between arms. Multivariate odds ratios (ORs) for immediate LLETZ vs biopsy and recall were computed.

RESULTS

Over the entire follow-up, there was no significant difference between arms in cumulative prevalence or risk of significant depression (OR=0.78, 95% CI 0.52-1.17) or significant anxiety (OR=0.83, 95% CI 0.57-1.19). At 6 weeks post procedure, distress did not differ significantly between arms. At later time points, 8-11% had significant depression and 14-16% had significant anxiety but with no differences between arms. The POSM scores did not differ between the arms.

CONCLUSIONS

There is no difference in long- or short-term psychosocial outcomes of immediate LLETZ and punch biopsies with selective recall.

Real time control for reduced aeration and chemical consumption: a full scale study

The use of the activated sludge process (ASP) for the nitrification/denitrification of wastewaters is commonplace throughout the UK and many other parts of the industrial world. Associated with this process are significant costs arising from aeration requirements and for selected sites, the need to provide an external carbon source. These costs can constitute up to of 50% of the total running cost of the whole plant and as such, any effort to reduce them could realise significant benefits. This paper investigates the use of real time control (RTC) using online sensors and control algorithms to optimise the operation of the ASP, leading to greater efficiency and sustainability. Trials were undertaken at full scale to assess the benefit of such a system at a 250,000 population equivalent (PE) works on the south coast of the UK, using Activated sludge model No.1 (ASM 1) as a basis for the control system. Initial results indicate that it is possible to significantly reduce both aeration and chemical consumption costs whilst still delivering the required effluent quality. Over the trial period the aeration requirements were consistently reduced by 20% whereas, a reduction in methanol consumption of in excess of 50% was observed.