The Community Burden of Influenza

Background: Influenza causes substantial morbidity and mortality. Novel strains from animals can infect humans, but such transmission is poorly understood. Serosurveillance estimates levels of influenza population immunity and infection but obtaining representative sera is challenging. Health-related quality of life (HRQoL) and absenteeism inform cost-effectiveness models of influenza interventions but these parameters are poorly understood. The National Pandemic Flu Service (NPFS) aimed to treat community cases. Little is known about the scheme’s coverage or effectiveness. / Objectives: 1) Investigate whether occupational exposure to pigs increases risk of seasonal, pandemic and zoonotic influenza infection. 2) Describe population-level patterns of influenza infection and immunity in England during 2012/13. 3) Quantify work and school absences and HRQoL from community influenza illnesses. 4) Evaluate the success of the NPFS and propose algorithm changes to improve antiviral targeting. / Methods: Flu Watch is a prospective community cohort of influenza and included recruitment of pig workers during the 2009 pandemic. The Pandemic Immunity and Population Spread study (PIPS) is a novel, population-level, cross-sectional, pandemic serosurveillance system utilizing the Health Survey for England. / Results: Pig workers had increased odds of seropositivity to seasonal, pandemic, and zoonotic influenza compared to the general population. A(H1N1)pdm09 and A(H3N2) infected 40% and 25% of the population in 2012/13. HRQoL loss and absenteeism is low for individual community-level influenza cases. NPFS consultation was low and the case definition specificity was 51%. / Conclusions: Influenza spreads readily from pigs to pig workers, posing risks for novel virus emergence and pandemics. Representative, population-level serology show that, before COVID-19, a large proportion of the population was infected each winter. Most community influenza cases take little time off work and school and this has implications for transmission. The coverage and impact of NPFS was low. Community-based surveys are needed to inform the control of seasonal and pandemic respiratory infections

Making use of Capuchins’ behavioral propensities to obtain hair samples for DNA analyses

Genotyping wild and captive capuchins has become a priority and hair bulbs have high quality DNA. Here, we describe a method to non-invasively collect fresh-plucked strands of hair that exploits capuchins’ manual dexterity and propensity to grasp and extract food. The apparatus consists of a transparent tube baited with food. Its extraction requires the monkey to place its forearm in contact with double-sided tape applied on the inner surface of the tube entrance. The “tube” method, successfully implemented with captive (N=23) and wild (N=21) capuchins, allowed us to obtain hair bulbs from most individuals and usable genomic DNA was extracted even from a single bulb

Development of guidelines for construction control of pile driving and estimation of pile capacity

Journal ArticleThe work upon which this report is based was supported by the Washington State Department of Transportation and the U. S. Department of Transportation, Federal highway Administration

Cyclic Strength Evaluation of Rockfill Dams

A method of modeling the cyclic behavior of gravelly soils containing particles too large to be tested in standard laboratory equipment has been described. This matrix model is based on the understanding that oversize particles floating in a matrix of smaller grains can be removed without significantly affecting the cyclic behavior of the total soil. Successful modeling of the total soil requires that the matrix be tested at the same relative density as that of the total material. Cyclic triaxial test results on two different gravelly soils are presented. Results of tests performed on the total soil with maximum grain size of 2 in. are accurately predicted by cyclic tests on smaller samples of matrix soil with 0.5 in. maximum grain size

Proximate factors underpinning receiver responses to deceptive false alarm calls in wild tufted capuchin monkeys: is it counterdeception?

Previous research demonstrates that tufted capuchin monkeys use terrestrial predator alarm calls in a functionally deceptive manner to distract conspecifics when feeding on contestable resources, although the success of this tactic is limited because listeners frequently ignore these calls when given in such situations. While this decreased response rate is suggestive of a counterstrategy to deception by receivers, the proximate factors underpinning the behavior are unclear. The current study aims to test if the decreased response rate to alarm calls in competitive contexts is better explained by the perception of subtle acoustic differences between predator-elicited and deceptive false alarms, or by receivers varying their responses based on the context in which the signal is received. This was tested by first examining the acoustic structure of predator-elicited and deceptive false alarms for any potentially perceptible acoustic differences, and second by comparing the responses of capuchins to playbacks of each of predator-elicited and false alarms, played back in noncompetitive contexts. The results indicate that deceptive false alarms and predator-elicited alarms show, at best, minimal acoustic differences based on the structural features measured. Likewise, playbacks of deceptive false alarms elicited antipredator reactions at the same rate as did predator-elicited alarms, although there was a nonsignificant tendency for false alarms to be more likely to elicit escape reactions. The lack of robust acoustic differences together with the high response rate to false alarms in noncompetitive contexts suggests that the context in which the signal is received best explains receiver responses. It remains unclear, however, if listeners ascribe different meanings to the calls based on context, or if they generally ignore all signals in competitive contexts. Whether or not the decreased response rate of receivers directly stems from the deceptive use of the calls cannot be determined until these latter possibilities are rigorously tested

A rapid review and meta-analysis of the asymptomatic proportion of PCR-confirmed SARS-CoV-2 infections in community settings [version 1; peer review: awaiting peer review]

Background: Cross-sectional studies indicate that up to 80% of active SARS-CoV-2 infections may be asymptomatic. However, accurate estimates of the asymptomatic proportion require systematic detection and follow-up to differentiate between truly asymptomatic and pre-symptomatic cases. We conducted a rapid review and meta-analysis of the asymptomatic proportion of PCR-confirmed SARS-CoV-2 infections based on methodologically appropriate studies in community settings. / Methods: We searched Medline and EMBASE for peer-reviewed articles, and BioRxiv and MedRxiv for pre-prints published before 25/08/2020. We included studies based in community settings that involved systematic PCR testing on participants and follow-up symptom monitoring regardless of symptom status. We extracted data on study characteristics, frequencies of PCR-confirmed infections by symptom status, and (if available) cycle threshold/genome copy number values and/or duration of viral shedding by symptom status, and age of asymptomatic versus (pre)symptomatic cases. We computed estimates of the asymptomatic proportion and 95% confidence intervals for each study and overall using random effect meta-analysis. / Results: We screened 1138 studies and included 21. The pooled asymptomatic proportion of SARS-CoV-2 infections was 23% (95% CI 16%-30%). When stratified by testing context, the asymptomatic proportion ranged from 6% (95% CI 0-17%) for household contacts to 47% (95% CI 21-75%) for non-outbreak point prevalence surveys with follow-up symptom monitoring. Estimates of viral load and duration of viral shedding appeared to be similar for asymptomatic and symptomatic cases based on available data, though detailed reporting of viral load and natural history of viral shedding by symptom status were limited. Evidence into the relationship between age and symptom status was inconclusive. / Conclusion: Asymptomatic viral shedding comprises a substantial minority of SARS-CoV-2 infections when estimated using methodologically appropriate studies. Further investigation into variation in the asymptomatic proportion by testing context, the degree and duration of infectiousness for asymptomatic infections, and demographic predictors of symptom status are warranted

Investigating obesity as a risk factor for influenza-like illness during the 2009 H1N1 influenza pandemic using the Health Survey for England.

BACKGROUND: Following the 2009 H1N1 influenza pandemic, obesity was shown to be associated with severe influenza outcomes. It remains unclear whether obesity was a risk factor for milder influenza-like illness (ILI). OBJECTIVES: To determine whether obesity was associated with an increased risk of self-reported ILI during the 2009 H1N1 influenza pandemic using Health Survey for England (HSE) 2010 cross-sectional data. METHODS: This study used HSE data collected from English households between January and December 2010. Weight and height measurements were taken by trained fieldworkers to determine obesity. ILI was defined as a positive response to the question "Have you had a flu-like illness where you felt feverish and had a cough or sore throat?" with illness occurring between May and December 2009. Multivariable logistic regression was used to evaluate the association between obesity and ILI. RESULTS: The study comprised 8407 participants (6984 adults, 1436 children), among whom 24.7% (95% CI: 23.6-25.9) were classified as obese. Of obese participants, 12.8% (95% CI: 11.1-14.8) reported ILI compared to 11.8% (95% CI: 10.8-12.8) of non-obese participants. The adjusted OR for ILI associated with obesity was 1.16 (95% CI: 0.98-1.38, P=.093). For adults and children, the adjusted ORs were 1.16 (95% CI: 0.97-1.38, P=.101) and 1.26 (95% CI: 0.72-2.21, P=.422), respectively. CONCLUSION: Household survey data showed no evidence that obesity was associated with an increase in self-reported ILI during the 2009 H1N1 influenza pandemic in England. Further studies using active prospective ILI surveillance combined with laboratory reporting would reduce bias and improve accuracy of outcome measurements

Emerging scarcity and emerging commons: Water management groups and groundwater governance in Aotearoa New Zealand

In New Zealand, intensifying agricultural production, particularly in the Canterbury and Heretaunga Plains, has led to groundwater overabstraction. Aquifer connectivity to lowland streams results in decreased streamflow with concomitant impacts on nutrient concentrations and other relevant factors for indigenous flora and fauna. Recent legislative reforms including the 2017 amendments to the National Policy Statement – Freshwater Management have increased local government responsibility and authority to address cumulative effects of diffuse resource use and have increased pressure on agricultural communities to farm within environmental constraints. Numerous water management groups (WMGs) have emerged across New Zealand in the past decade to deal with these reforms and ensure reliability of irrigation water supply. Regional governments view WMGs as helpful in dealing with water allocation challenges and integrated environmental management approaches. This paper uses two case study WMGs from Hawke’s Bay and Canterbury to illustrate aspects of common property management and explore the viability of this type of localised resource governance. The study highlights how these WMGs have navigated groundwater, local government, and environmental management issues and how their local context and constraints shaped their development. It also illustrates how WMGs can engage with water quality and broader environmental challenges while ensuring members’ economic viability

Seasonality and immunity to laboratory-confirmed seasonal coronaviruses (HCoV-NL63, HCoV-OC43, and HCoV-229E): results from the Flu Watch cohort study [version 1; peer review: 2 approved with reservations]

Background: There is currently a pandemic caused by the novel coronavirus SARS-CoV-2. The intensity and duration of this first wave in the UK may be dependent on whether SARS-CoV-2 transmits more effectively in the winter than the summer and the UK Government response is partially built upon the assumption that those infected will develop immunity to reinfection in the short term. In this paper we examine evidence for seasonality and immunity to laboratory-confirmed seasonal coronavirus (HCoV) from a prospective cohort study in England. Methods: In this analysis of the Flu Watch cohort, we examine seasonal trends for PCR-confirmed coronavirus infections (HCoV-NL63, HCoV-OC43, and HCoV-229E) in all participants during winter seasons (2006-2007, 2007-2008, 2008-2009) and during the first wave of the 2009 H1N1 influenza pandemic (May-Sep 2009). We also included data from the pandemic and ‘post-pandemic’ winter seasons (2009-2010 and 2010-2011) to identify individuals with two confirmed HCoV infections and examine evidence for immunity against homologous reinfection. Results: We tested 1,104 swabs taken during respiratory illness and detected HCoV in 199 during the first four seasons. The rate of confirmed HCoV infection across all seasons was 390 (95% CI 338-448) per 100,000 person-weeks; highest in the Nov-Mar 2008/9 season at 674 (95%CI 537-835). The highest rate was in February at 759 (95% CI 580-975). Data collected during May-Sep 2009 showed there was small amounts of ongoing transmission, with four cases detected during this period. Eight participants had two confirmed infections, of which none had the same strain twice

Household transmission of seasonal coronavirus infections: Results from the Flu Watch cohort study [version 1; peer review: 1 approved, 2 approved with reservations]

Background: In the context of the current coronavirus disease 2019 (COVID-19) pandemic, understanding household transmission of seasonal coronaviruses may inform pandemic control. We aimed to investigate what proportion of seasonal coronavirus transmission occurred within households, measure the risk of transmission in households, and describe the impact of household-related factors of risk of transmission. Methods: Using data from three winter seasons of the UK Flu Watch cohort study, we measured the proportion of symptomatic infections acquired outside and within the home, the household transmission risk and the household secondary attack risk for PCR-confirmed seasonal coronaviruses. We present transmission risk stratified by demographic features of households. Results: We estimated that the proportion of cases acquired outside the home, weighted by age and region, was 90.7% (95% CI 84.6- 94.5, n=173/195) and within the home was 9.3% (5.5-15.4, 22/195). Following a symptomatic coronavirus index case, 14.9% (9.8 - 22.1, 20/134) of households experienced symptomatic transmission to at least one other household member. Onward transmission risk ranged from 11.90% (4.84-26.36, 5/42) to 19.44% (9.21-36.49, 7/36) by strain. The overall household secondary attack risk for symptomatic cases was 8.00% (5.31-11.88, 22/275), ranging across strains from 5.10 (2.11-11.84, 5/98) to 10.14 (4.82- 20.11, 7/69). Median clinical onset serial interval was 7 days (IQR= 6-9.5). Households including older adults, 3+ children, current smokers, contacts with chronic health conditions, and those in relatively deprived areas had the highest transmission risks. Child index cases and male index cases demonstrated the highest transmission risks. Conclusion: Most seasonal coronaviruses appear to be acquired outside the household, with relatively modest risk of onward transmission within households. Transmission risk following an index case appears to vary by demographic household features, with potential overlap between those demonstrating the highest point estimates for seasonal coronavirus transmission risk and COVID-19 susceptibility and poor illness outcomes