Disease severity determines health-seeking behaviour amongst individuals with influenza-like illness in an internet-based cohort

A shared journey: evaluating a patient-assessed measure of self-management of chronic conditions in an Australian setting

Background Patient Assessment of Care in Chronic Conditions (PACIC+), included in some Australian guidelines, has been shown reliable for measuring patient engagement and perception of their care in primary care settings. Various studies have focussed on PACIC+ use in specific conditions. This study aims to expand PACIC+ to measure patient empowerment to self-manage their chronic condition and validate it in the broader Australian primary care population. This study aims to evaluate internal consistency and reliability of PACIC+ and six new supplementary items proposed to assess patient wellbeing and empowerment to self-manage their chronic condition. Methods A repeated-measures correlation design study assessed the expanded PACIC+ over three time-points. Particpants were patients with at least one chronic disease, referred by consultant physician, or recruited by advertisement posters in hospital clinic areas. Results PACIC+ (26-item) had acceptable internal consitency (Cronbach's alpha 0.96). Test-retest reliability (Time-1 and 2, P r (48)=0.43; and New supplementary items: Confidence r (48)=0.54; Understanding r (48)=0.62; Support r (48)=0.43; Overall Health r (48)=0.42; Overall Health Change r (48)=-0.31, P =0.03; and Acute Episodes of Care in 1-month r (48)=0.42, P Conclusions The expanded PACIC+ is an improved psychometric tool providing for the patient's voice in a shared health journey. It is a valid, reliable tool to monitor and measure self-management of chronic conditions in Australian population clinic and primary healthcare settings.

Estimating and Explaining the Differences in Health Care Seeking by Symptom Burden Among Persons With Presumptive Tuberculosis: Findings From a Population-Based Tuberculosis Prevalence Survey in a High-Burden Setting in India

Background

There is a lack of research evidence on the quantitative relationship between symptom burden and health care seeking among individuals with presumptive tuberculosis (TB).

Methods

Data were derived from a cross-sectional population-based TB survey conducted between February 2021 and July 2022 in 32 districts of India. Eligible and consented participants (age >15 years) underwent TB symptom screening and history elicitation. Fairlie decomposition analysis was used to estimate the net differences in health care seeking due to varied symptom burden-from 1+ burden (>1 symptom) to 4+ burden (>4 symptoms)-and decomposed by observable covariates based on logit models with 95% CIs.

Results

Of the 130 932 individuals surveyed, 9540 (7.3%) reported at least 1 recent TB symptom, of whom 2678 (28.1%; 95% CI, 27.1%-28.9%) reportedly sought health care. The net differences in health care seeking among persons with symptom burden 1+ to 4+ ranged from 6.6 percentage points (95% CI, 4.8-8.4) to 7.7 (95% CI, 5.2-10.2) as compared with persons with less symptom burden. The presence of expectoration, fatigue, and loss of appetite largely explained health care seeking (range, 0.9-3.1 percentage points [42.89%-151.9%]). The presence of fever, cough, past TB care seeking, weight loss, and chest pain moderately explained (range, 5.3%-25.3%) health care seeking.

Conclusions

Increased symptom burden and symptoms other than the commonly emphasized cough and fever largely explained health care seeking. Orienting TB awareness and risk communications toward symptom burden and illness perceptions could help address population gaps in health care seeking for TB.

Test-Negative Study Designs for Evaluating Vaccine Effectiveness

This JAMA Guide to Statistics and Methods article explains the test-negative study design, an observational study design routinely used to estimate vaccine effectiveness, and examines its use in a study that estimated the performance of messenger RNA boosters against the Omicron variant.

Key Challenges for Respiratory Virus Surveillance while Transitioning out of Acute Phase of COVID-19 Pandemic

To support the ongoing management of viral respiratory diseases while transitioning out of the acute phase of the COVID-19 pandemic, many countries are moving toward an integrated model of surveillance for SARS-CoV-2, influenza virus, and other respiratory pathogens. Although many surveillance approaches catalyzed by the COVID-19 pandemic provide novel epidemiologic insight, continuing them as implemented during the pandemic is unlikely to be feasible for nonemergency surveillance, and many have already been scaled back. Furthermore, given anticipated cocirculation of SARS-CoV-2 and influenza virus, surveillance activities in place before the pandemic require review and adjustment to ensure their ongoing value for public health. In this report, we highlight key challenges for the development of integrated models of surveillance. We discuss the relative strengths and limitations of different surveillance practices and studies as well as their contribution to epidemiologic assessment, forecasting, and public health decision-making.

Changes in public health-seeking behaviours for self-limiting respiratory tract infections across England during the COVID-19 pandemic

BACKGROUND

National Health Service (NHS) guidance for acute respiratory tract infections (RTIs) advocates self-care, encourages utilization of local pharmacies and recommends consulting general practitioners (GPs) primarily for the vulnerable or those with persistent symptoms. Coronavirus disease 2019 exerted substantial strain on the English NHS, affecting public access to primary care services.

METHODS

For 3 years, public surveys assessed RTI incidences in the previous 12 months and associated health-seeking behaviours. Telephone surveys of 1676 respondents across England were conducted in March 2021 and 1663 respondents in March 2022. Findings were compared with a face-to-face baseline survey of 2022 respondents from March 2020. Key demographics were representative of the population.

RESULTS

In 2021, the proportion of respondents who reported an RTI (51%) significantly declined from 2020 (70%, P < 0.05), then returned to pre-pandemic rates in 2022 (67%). Respondents reported more proactive symptom management in both 2021 and 2022 from 2020: there were greater reports of seeking over-the-counter treatments (55%, 55% vs. 35%, P < 0.05) and use of alternative remedies (38%, 38% vs. 21%, P < 0.05). 2022 observed a reduction in those who reported consulting their GP for their most recent RTI (15%) compared to 2021 (25%, P < 0.05) and 2020 (23%), which was not accounted for through greater consultation rates with other healthcare services.

CONCLUSIONS

Public health bodies should consider how pandemic-related changes may have facilitated increased self-care for self-limiting infections such as RTIs. Resources and support must include safety-netting advice to safeguard against unintentional consequences of increased self-care.

Factors associated with health-seeking patterns among internally displaced persons in complex humanitarian emergency, Northeast Nigeria: a cross-sectional study

BACKGROUND

Currently, over two million persons are internally displaced because of the complex humanitarian emergency in Nigeria's northeast region. Due to crowded and unsanitary living conditions, the risk of communicable disease transmission, morbidity, and mortality among this population is high. This study explored patterns and factors associated with health-seeking among internally displaced persons (IDPs) in northeast Nigeria to inform and strengthen disease surveillance and response activities.

METHODS

In a cross-sectional study conducted during June-October 2022, we employed stratified sampling technique to select 2,373 IDPs from 12 IDPs camps. A semi-structured tool was used to collect data on health-seeking patterns, socio-demographics, households, and IDPs camps characteristics. We classified health-seeking patterns into three outcome categories: 'facility care' (reference category), 'non-facility care' (patent medicine vendors, chemists, traditional healers, religious centers), and 'home care/no care'. We performed complex survey data analysis and obtained weighted statistical estimates. Univariate analysis was conducted to describe respondents' characteristics and health-seeking patterns. We fitted weighted multivariable multinomial logistic regression models to identify factors associated with health-seeking patterns.

RESULTS

Of 2,373 respondents, 71.8% were 18 to 39 years old, 78.1% were females, and 81.0% had no formal education. Among the respondents, 75.7% (95% CI: 72.9-78.6) sought 'facility care', 11.1% (95% CI: 9.1-13.1) sought 'non-facility care', while 13.2% (95% CI: 10.9-15.4) practiced 'home care/no care'. Respondents who perceived illness was severe (Adjusted Odds Ratio (AOR) = 0.15, [95% CI: 0.08-0.30]) and resided in officially-recognized camps (AOR = 0.26, [95% CI: 0.17-0.39]) were less likely to seek 'non-facility care' compared to 'facility care'. Similarly, respondents who resided in officially-recognized camps (AOR = 0.58, [95% CI: 0.36-0.92]), and received disease surveillance information (AOR = 0.42, [95% CI: 0.26-0.67) were less likely to practice 'home care/no care' rather than seek 'facility care'.

CONCLUSIONS

This population exhibited heterogeneous patterns of health-seeking at facility and non-facility centers. Perception of illness severity and camps' status were major factors associated with health-seeking. To enhance surveillance, non-facility care providers should be systematically integrated into the surveillance network while ramping up risk communication to shape perception of illness severity, prioritizing unofficial camps.

Care-seeking correlates of acute respiratory illness among sheltered adults experiencing homelessness in Seattle, WA, 2019: a community-based cross-sectional study

Objective

Multifarious barriers to accessing healthcare services among people experiencing homelessness (PEH) lead to delays in seeking care for acute infections, including those caused by respiratory viruses. PEH are at high risk of acute respiratory illness (ARI)-related complications, especially in shelter settings that may facilitate virus spread, yet data characterizing healthcare utilization for ARI episodes among sheltered PEH remained limited.

Methods

We conducted a cross-sectional study of viral respiratory infection among adult residents at two homeless shelters in Seattle, Washington between January and May 2019. We assessed factors associated with seeking medical care for ARI via self-report. We collected illness questionnaires and nasal swabs were tested for respiratory viruses by reverse transcription quantitative real-time PCR (RT-qPCR).

Results

We observed 825 encounters from 649 unique participants; 241 (29.2%) encounters reported seeking healthcare for their ARI episode. Seasonal influenza vaccine receipt (adjusted prevalence ratio [aPR] 1.39, 95% CI 1.02-1.88), having health insurance (aPR 2.77, 95% CI 1.27-6.02), chronic lung conditions (aPR 1.55, 95% CI 1.12-2.15), and experiencing influenza-like-illness symptoms (aPR 1.63, 95% CI 1.20 - 2.20) were associated with increased likelihood of seeking care. Smoking (aPR 0.65, 95% CI 0.45-0.92) was associated with decreased likelihood of seeking care.

Discussion

Findings suggest that care seeking for viral respiratory illness among PEH may be supported by prior engagement with primary healthcare services. Strategies to increase healthcare utilization may lead to earlier detection of respiratory viruses.

Impact of influenza vaccination on GP-diagnosed COVID-19 and all-cause mortality: a Dutch cohort study

OBJECTIVES

As clinical presentation and complications of both viruses overlap, it was hypothesised that influenza vaccination was associated with lower general practitioner (GP)-diagnosed COVID-19 rates and lower all-cause mortality rates.

STUDY DESIGN

From a primary care population-based cohort in the Netherlands, GP-diagnosed COVID-19 (between 10 March and 22 November 2020) and all-cause mortality events (between 30 December 2019 and 22 November 2020) were recorded. 223 580 persons were included, representing the influenza vaccination 2019 target group (all aged ≥60 years, and those <60 years with a medical indication). Proportional hazards regression analyses evaluated associations between influenza vaccination in 2019 and two outcomes: GP-diagnosed COVID-19 and all-cause mortality. Covariables were sex, age, comorbidities and number of acute respiratory infection primary care consultations in 2019.

RESULTS

A slightly positive association (HR 1.15; 95% CI 1.08 to 1.22) was found between influenza vaccination in 2019 and GP-diagnosed COVID-19, after adjusting for covariables. A slightly protective effect for all-cause mortality rates (HR 0.90; 95% CI 0.83 to 0.97) was found for influenza vaccination, after adjusting for covariables. A subgroup analysis among GP-diagnosed COVID-19 cases showed no significant association between influenza vaccination in 2019 and all-cause mortality.

CONCLUSIONS

Our hypothesis of a possibly negative association between influenza vaccination in 2019 and GP-diagnosed COVID-19 was not confirmed as we found a slightly positive association. A slightly protective effect on all-cause mortality was found after influenza vaccination, possibly by a wider, overall protective effect on health. Future research designs should include test-confirmed COVID-19 cases and controls, adjustments for behavioural, socioeconomic and ethnic factors and validated cause-specific mortality cases.

Respiratory Infections Are More Common Than Healthcare Records Indicate: Results From an Anonymous Survey

INTRODUCTION

Influenza-like illnesses (ILIs) are common in military populations and can impair mission-readiness, particularly in the current severe acute respiratory syndrome coronavirus 2 pandemic; therefore, it is important to identify potential risk factors for infection and better understand the burden of infection.

MATERIALS AND METHODS

A survey was administered to military medical trainees living in a congregated setting on JBSA Fort Sam Houston, Texas, from January 2017 to February 2019. The survey included questions about ILI experience and potential ILI risk factors.

RESULTS

2,121 individuals completed the survey. Respondents had a median age of 21 years, 46% were female, 32.6% were Air Force, 33.6% were Army, and 33.8% were Navy/Marines. Among the 815 (38%) who reported an ILI during training, 40% sought health care. The primary reasons for seeking healthcare included illness severity, concern about transmission, and accessibility of healthcare. Over half (54%) of the trainees who reported an ILI said the ILI had an impact on their performance, including reduced study time, missed physical training, and missed class. Multivariate model results indicate that women and younger trainees (<30 years) were more likely to report having had an ILI (women: OR 1.58, (95% CI 1.30, 1.92); age <30 years: OR 1.58, (1.06, 2.36)). In a subset analysis, those who reported washing their hands 10+ times per day were less likely to report an ILI (OR 0.61 (0.42, 0.89)).

CONCLUSIONS

ILIs are likely to be more common during training than healthcare records indicate and may result in decreased training effectiveness. Increasing access to handwashing facilities and education about the importance of handwashing to prevent the spread of disease will likely reduce the ILI burden in this population.

Association of infant antibiotic exposure and risk of childhood asthma: A meta-analysis

Background

Infant antibiotic exposure may be associated with childhood asthma development.

Objective

To examine and detail this association considering potential confounders.

Study design

PubMed, EMBASE, Web of Science, and the Cochrane Library were searched for publications from January 2011 to March 2021. Eligible studies were independently reviewed to extract data and assess quality. Random effect model was used to pool odds ratio (OR) and corresponding 95% confidence intervals (CIs).

Results

A total of 52 studies were included. The association of infant antibiotic exposure and childhood asthma was statistically significant for overall analysis (OR, 1.37; 95% CI, 1.29-1.45) and for studies that addressed reverse causation (RC) and confounding by indication (CbI) (1.19; 95% CI, 1.11-1.28). Significance remained after stratification by adjustment for maternal antibiotic exposure, medical consultation, sex, smoke exposure, parental allergy, birth weight, and delivery mode. In detailed analyses, macrolides (OR, 1.56; 95% CI, 1.31-1.86), antibiotic course≥5 (OR, 1.79; 95% CI, 1.36-2.36), exposure within 1 week of birth (OR, 1.82; 95% CI, 1.34-2.47), asthma developed among 1-3 years (OR, 1.84; 95% CI, 1.63-2.08), short time lag between exposure and asthma onset (OR, 2.05; 95% CI, 1.91-2.20), persistent asthma (OR, 2.61; 95% CI, 1.49-4.59), and atopic asthma (OR, 2.14; 95% CI, 1.58-2.90) showed higher pooled estimates.

Conclusion

Infant antibiotic exposure is associated with increased risk of childhood asthma considering confounding, and the association varied with different settings of exposure and outcomes. This highlights the need for prevention of asthma after early antibiotic exposure. Heterogeneity among studies called for caution when interpretation.

The performance of COVID-19 Surveillance System as timely containment strategy in Western Oromia, Ethiopia

BACKGROUND

COVID-19 has been swiftly spreading throughout the world ever since it emerged in Wuhan, China, in late December 2019. Case detection and contact identification remain the key surveillance objectives for effective containment of the pandemic. This study was aimed at assessing performance of surveillance in early containment of COVID 19 in Western Oromia, Ethiopia.

METHODS

A cross-sectional study was conducted from August 1 to September 30, 2020, in the 7 kebeles of Nekemte and 2 kebeles of Shambu Town. Residents who lived there for at least the past six months were considered eligible for this study. Data were collected from community and health system at different levels using semi structured questionnaire and checklist, respectively. Participants' health facility usage (dependent variable) and perceived risk, awareness, Socioeconomic Status, and practices (independent variable) were assessed. Bivariable analysis was computed to test the presence of an association between dependent and independent variables. Independent predictors were identified on multivariable logistic regression using a p-value of (<0.05) significance level. We have checked the model goodness of fit test by Hosmer-lemeshow test.

RESULTS

One hundred seventy-nine (41%) of the participants believe that they have a high risk of contracting COVID-19 and 127 (29%) of them reported they have been visited by health extension worker. One hundred ninety-seven (45.2%) reported that they were not using health facilities for routine services during this pandemic. Except one hospital, all health facilities (92%) were using updated case definition. Three (33%) of the assessed health posts didn't have community volunteers. On multivariable logistic regression analysis, the source of income AOR=0.30, 95% CI (0.11, 0.86), perceived level of risk AOR=3.42, 95% CI (2.04, 5.7) and not visited by health extension workers AOR=0.46, 95% CI (0.29, 0.74) were found to be independent predictors of not using health facilities during this pandemic.

CONCLUSION

Event based surveillance, both at community and health facility level, was not performing optimally in identifying potential suspects. Therefore, for effective early containment of epidemic, it is critical to strengthen event based surveillance and make use of surveillance data for tailored intervention in settings where mass testing is not feasible.

Spotlight influenza: Laboratory-confirmed seasonal influenza in people with acute respiratory illness: a literature review and meta-analysis, WHO European Region, 2004 to 2017

BackgroundAcross the World Health Organization European Region, there are few estimates of the proportion of people seeking medical care for influenza-like illness or acute respiratory infections and who have laboratory-confirmed seasonal influenza infection.MethodsWe conducted a meta-analysis of data extracted from studies published between 2004 and 2017 and from sentinel data from the European surveillance system (TESSy) between 2004 and 2018. We pooled within-season estimates by influenza type/subtype, setting (outpatient (OP)/inpatient (IP)) and age group to estimate the proportion of people tested who have laboratory-confirmed and medically-attended seasonal influenza in Europe.ResultsIn the literature review, the pooled proportion for all influenza types was 33% (95% confidence interval (CI): 30-36), higher among OP 36% (95% CI: 33-40) than IP 24% (95% CI: 20-29). Pooled estimates for all influenza types by age group were: 0-17 years, 26% (22-31); 18-64 years, 41% (32-50); ≥ 65 years, 33% (27-40). From TESSy data, 33% (31-34) of OP and 24% (21-27) of IP were positive. The highest proportion of influenza A was in people aged 18-64 years (22%, 16-29). By subtype, A(H1N1)pdm09 was highest in 18-64 year-olds (16%, 11-21%) whereas A(H3N2) was highest in those ≥ 65 years (10%, 2-22). For influenza B, the highest proportion of infections was in those aged 18-64 years (15%, 9-24).ConclusionsLaboratory-confirmed influenza accounted for approximately one third of all acute respiratory infections for which medical care was sought during the influenza season.

Risk factors associated with the incidence of self-reported COVID-19-like illness: data from a web-based syndromic surveillance system in the Netherlands

During the first wave of the severe acute respiratory syndrome-coronavirus-2 epidemic in the Netherlands, notifications consisted mostly of patients with relatively severe disease. To enable real-time monitoring of the incidence of mild coronavirus disease 2019 (COVID-19) – for which medical consultation might not be required – the Infectieradar web-based syndromic surveillance system was launched in mid-March 2020. Our aim was to quantify associations between Infectieradar participant characteristics and the incidence of self-reported COVID-19-like illness. Recruitment for this cohort study was via a web announcement. After registering, participants completed weekly questionnaires, reporting the occurrence of a set of symptoms. The incidence rate of COVID-19-like illness was estimated and multivariable Poisson regression used to estimate the relative risks associated with sociodemographic variables, lifestyle factors and pre-existing medical conditions. Between 17 March and 24 May 2020, 25 663 active participants were identified, who reported 7060 episodes of COVID-19-like illness over 131 404 person-weeks of follow-up. The incidence rate declined over the analysis period, consistent with the decline in notified cases. Male sex, age 65+ years and higher education were associated with a significantly lower COVID-19-like illness incidence rate (adjusted rate ratios (RRs) of 0.80 (95% CI 0.76–0.84), 0.77 (0.70–0.85), 0.84 (0.80–0.88), respectively) and the baseline characteristics ever-smoker, asthma, allergies, diabetes, chronic lung disease, cardiovascular disease and children in the household were associated with a higher incidence (RRs of 1.11 (1.04–1.19) to 1.69 (1.50–1.90)). Web-based syndromic surveillance has proven useful for monitoring the temporal trends in, and risk factors associated with, the incidence of mild disease. Increased relative risks observed for several patient factors could reflect a combination of exposure risk, susceptibility to infection and propensity to report symptoms.

Classification of covid related articles using machine learning

Covid 19 pandemic has placed the entire world in a precarious condition. Earlier it was a serious issue in china whereas now it is being witnessed by citizens all over the world. Scientists are working hard to find treatment and vaccines for the coronavirus, also termed as covid. With the growing literature, it has become a major challenge for the medical community to find answers to questions related to covid-19. We have proposed a machine learning-based system that uses text classification applications of NLP to extract information from the scientific literature. Classification of large textual data makes the searching process easier thus useful for scientists. The main aim of our system is to classify the abstracts related to covid with their respective journals so that a researcher can refer to articles of his interest from the required journals instead of searching all the articles. In this paper, we describe our methodology needed to build such a system. Our system experiments on the COVID-19 open research dataset and the performance is evaluated using classifiers like KNN, MLP, etc. An explainer was also built using XGBoost to show the model predictions.

Incidence, healthcare-seeking behaviours, antibiotic use and natural history of common infection syndromes in England: results from the Bug Watch community cohort study

BACKGROUND

Better information on the typical course and management of acute common infections in the community could inform antibiotic stewardship campaigns. We aimed to investigate the incidence, management, and natural history of a range of infection syndromes (respiratory, gastrointestinal, mouth/dental, skin/soft tissue, urinary tract, and eye).

METHODS

Bug Watch was an online prospective community cohort study of the general population in England (2018-2019) with weekly symptom reporting for 6 months. We combined symptom reports into infection syndromes, calculated incidence rates, described the proportion leading to healthcare-seeking behaviours and antibiotic use, and estimated duration and severity.

RESULTS

The cohort comprised 873 individuals with 23,111 person-weeks follow-up. The mean age was 54 years and 528 (60%) were female. We identified 1422 infection syndromes, comprising 40,590 symptom reports. The incidence of respiratory tract infection syndromes was two per person year; for all other categories it was less than one. 194/1422 (14%) syndromes led to GP (or dentist) consultation and 136/1422 (10%) to antibiotic use. Symptoms usually resolved within a week and the third day was the most severe.

CONCLUSIONS

Most people reported managing their symptoms without medical consultation. Interventions encouraging safe self-management across a range of acute infection syndromes could decrease pressure on primary healthcare services and support targets for reducing antibiotic prescribing.

Exploring the percentage of COVID-19 cases reported in the community in Canada and associated case fatality ratios

While surveillance can identify changes in COVID-19 transmission patterns over time and space, sections of the population at risk, and the efficacy of public health measures, reported cases of COVID-19 are generally understood to only capture a subset of the actual number of cases. Our primary objective was to estimate the percentage of cases reported in the general community, considered as those that occurred outside of long-term care facilities (LTCFs), in specific provinces and Canada as a whole. We applied a methodology using the delay-adjusted case fatality ratio (CFR) to all cases and deaths, as well as those representing the general community. Our second objective was to assess whether the assumed CFR (mean = 1.38%) was appropriate for calculating underestimation of cases in Canada. Estimates were developed for the period from March 11th, 2020 to September 16th, 2020. Estimates of the percentage of cases reported (PrCR) and CFR varied spatially and temporally across Canada. For the majority of provinces, and for Canada as a whole, the PrCR increased through the early stages of the pandemic. The estimated PrCR in general community settings for all of Canada increased from 18.1% to 69.0% throughout the entire study period. Estimates were greater when considering only those data from outside of LTCFs. The estimated upper bound CFR in general community settings for all of Canada decreased from 9.07% on March 11th, 2020 to 2.00% on September 16th, 2020. Therefore, the true CFR in the general community in Canada was likely less than 2% on September 16th. According to our analysis, some provinces, such as Alberta, Manitoba, Newfoundland and Labrador, Nova Scotia, and Saskatchewan reported a greater percentage of cases as of September 16th, compared to British Columbia, Ontario, and Québec. This could be due to differences in testing rates and criteria, demographics, socioeconomic factors, race, and access to healthcare among the provinces. Further investigation into these factors could reveal differences among provinces that could partially explain the variation in estimates of PrCR and CFR identified in our study. The estimates provide context to the summative state of the pandemic in Canada, and can be improved as knowledge of COVID-19 reporting rates and disease characteristics are advanced.

Influencing public health policy with data-informed mathematical models of infectious diseases: Recent developments and new challenges

Modern data and computational resources, coupled with algorithmic and theoretical advances to exploit these, allow disease dynamic models to be parameterised with increasing detail and accuracy. While this enhances models' usefulness in prediction and policy, major challenges remain. In particular, lack of identifiability of a model's parameters may limit the usefulness of the model. While lack of parameter identifiability may be resolved through incorporation into an inference procedure of prior knowledge, formulating such knowledge is often difficult. Furthermore, there are practical challenges associated with acquiring data of sufficient quantity and quality. Here, we discuss recent progress on these issues.

Impact of influenza vaccination programmes among the elderly population on primary care, Portugal, Spain and the Netherlands: 2015/16 to 2017/18 influenza seasons

Background

To increase the acceptability of influenza vaccine, it is important to quantify the overall benefits of the vaccination programme.

Aim

To assess the impact of influenza vaccination in Portugal, Spain and the Netherlands, we estimated the number of medically attended influenza-confirmed cases (MAICC) in primary care averted in the seasons 2015/16 to 2017/18 among those ≥ 65 years.

Methods

We used an ecological approach to estimate vaccination impact. We compared the number of observed MAICC (n) to the estimated number that would have occurred without the vaccination programme (N). To estimate N, we used: (i) MAICC estimated from influenza surveillance systems, (ii) vaccine coverage, (iii) pooled (sub)type-specific influenza vaccine effectiveness estimates for seasons 2015/16 to 2017/18, weighted by the proportion of virus circulation in each season and country. We estimated the number of MAICC averted (NAE) and the prevented fraction (PF) by the vaccination programme.

Results

The annual average of NAE in the population ≥ 65 years was 33, 58 and 204 MAICC per 100,000 in Portugal, Spain and the Netherlands, respectively. On average, influenza vaccination prevented 10.7%, 10.9% and 14.2% of potential influenza MAICC each season in these countries. The lowest PF was in 2016/17 (4.9–6.1%) with an NAE ranging from 24 to 69 per 100,000.

Conclusions

Our results suggest that influenza vaccination programmes reduced a substantial number of MAICC. Together with studies on hospitalisations and deaths averted by influenza vaccination programmes, this will contribute to the evaluation of the impact of vaccination strategies and strengthen public health communication.

Health-care seeking behavior for respiratory illness among Flu Near You participants in the United States during the 2015-16 through 2018-19 influenza season

Background

Flu Near You (FNY) is an online participatory syndromic surveillance system that collects health-related information. In this article, we summarized the healthcare-seeking behavior of FNY participants who reported influenza-like illness (ILI) symptoms.

Methods

We applied inverse probability weighting to calculate age-adjusted estimates of the percentage of FNY participants in the United States who sought health care for ILI symptoms during the 2015–2016 through 2018–2019 influenza season and compared seasonal trends across different demographic and regional subgroups, including age group, sex, census region, and place of care using adjusted χ ² tests.

Results

The overall age-adjusted percentage of FNY participants who sought healthcare for ILI symptoms varied by season and ranged from 22.8% to 35.6%. Across all seasons, healthcare seeking was highest for the <18 and 65+ years age groups, women had a greater percentage compared with men, and the South census region had the largest percentage while the West census region had the smallest percentage.

Conclusions

The percentage of FNY participants who sought healthcare for ILI symptoms varied by season, geographical region, age group, and sex. FNY compliments existing surveillance systems and informs estimates of influenza-associated illness by adding important real-time insights into healthcare-seeking behavior.

Active surveillance documents rates of clinical care seeking due to respiratory illness

Background

Respiratory viral infections are a leading cause of disease worldwide. However, the overall community prevalence of infections has not been properly assessed, as standard surveillance is typically acquired passively among individuals seeking clinical care.

Methods

We conducted a prospective cohort study in which participants provided daily diaries and weekly nasopharyngeal specimens that were tested for respiratory viruses. These data were used to analyze healthcare seeking behavior, compared with cross‐sectional ED data and NYC surveillance reports, and used to evaluate biases of medically attended ILI as signal for population respiratory disease and infection.

Results

The likelihood of seeking medical attention was virus‐dependent: higher for influenza and metapneumovirus (19%‐20%), lower for coronavirus and RSV (4%), and 71% of individuals with self‐reported ILI did not seek care and half of medically attended symptomatic manifestations did not meet the criteria for ILI. Only 5% of cohort respiratory virus infections and 21% of influenza infections were medically attended and classifiable as ILI. We estimated 1 ILI event per person/year but multiple respiratory infections per year.

Conclusion

Standard, healthcare‐based respiratory surveillance has multiple limitations. Specifically, ILI is an incomplete metric for quantifying respiratory disease, viral respiratory infection, and influenza infection. The prevalence of respiratory viruses, as reported by standard, healthcare‐based surveillance, is skewed toward viruses producing more severe symptoms. Active, longitudinal studies are a helpful supplement to standard surveillance, can improve understanding of the overall circulation and burden of respiratory viruses, and can aid development of more robust measures for controlling the spread of these pathogens.

A Systematic Review and Meta-analysis of the Prevalence of Community-Onset Bloodstream Infections among Hospitalized Patients in Africa and Asia

Community-onset bloodstream infections (CO-BSI) are major causes of severe febrile illness and death worldwide. In light of new data and the growing problem of antimicrobial resistance (AMR) among pathogens causing BSI, we undertook a systematic review of hospital-based studies of CO-BSI among patients hospitalized with fever.

Community-onset bloodstream infections (CO-BSI) are major causes of severe febrile illness and death worldwide. In light of new data and the growing problem of antimicrobial resistance (AMR) among pathogens causing BSI, we undertook a systematic review of hospital-based studies of CO-BSI among patients hospitalized with fever. Without restriction to language or country, we searched PubMed, Web of Science, and Scopus for prospective hospital-based studies of culture-confirmed CO-BSI among febrile inpatients. We determined by study the prevalence of BSI among participants, the pathogens responsible for BSI, and the antimicrobial susceptibility patterns of pathogens causing BSI, according to place and time. Thirty-four (77.3%) of 44 eligible studies recruited 29,022 participants in Africa and Asia combined. Among participants in these two regions, the median prevalence of BSI was 12.5% (range, 2.0 to 48.4%); of 3,220 pathogens isolated, 1,119 (34.8%) were Salmonella enterica, 425 (13.2%) Streptococcus pneumoniae, and 282 (8.8%) Escherichia coli. Antimicrobial susceptibility testing was reported in 16 (36.4%) studies. When isolates collected prior to 2008 were compared to those collected in the period of 2008 through 2018, the proportions of typhoidal Salmonella and Staphylococcus aureus isolates resistant to several clinically relevant antimicrobials increased over time, while S. pneumoniae susceptibility was stable. CO-BSI remain a major cause of severe febrile illness among hospitalized patients in Africa and Asia, with S. enterica, S. pneumoniae, and E. coli predominating. There is a concerning increase in AMR among serious infections caused by community-onset pathogens. Ongoing surveillance is needed to inform empirical management and strategies to control AMR.

Probiotics Reduce Health Care Cost and Societal Impact of Flu-Like Respiratory Tract Infections in the USA: An Economic Modeling Study

Acute respiratory tract infections (RTIs) of viral origin place a substantial burden on health care resources and society. Randomized controlled trials have shown positive effects of probiotics on clinical outcomes in these commonly occurring RTIs. Two meta-analyses published by the York Health Economics Consortium (YHEC) and Cochrane reported the efficacy of probiotics in reducing incidence and duration of RTIs, number of antibiotic courses, and days absent from work. The aim of this study was to assess the potential health-economic impact of probiotics on RTI-associated events and expenses in the US primary care setting. A state-transition microsimulation model reproduced a study population representative of the US national demographics for age and gender (1/1,000 sample). RTI incidence was based on the influenza-like illness outpatient consultation rate reported by the Centers for Disease Control and Prevention (CDC) FluView. Data on vaccination, on factors that negatively impact RTI outcomes, on resource utilization, and on productivity loss were obtained from US national databases. Analyses were performed for both meta-analyses independently. Outcomes included cost savings for the health care payer, related to a reduced number of RTI episodes, less outpatient consultations, and decreased medical prescriptions as well as cost savings from a broader societal perspective related to productivity loss. The analysis showed that generalized probiotic intake in the US population for 2017-2018 would have allowed cost savings for the health care payer of 4.6 million USD based on the YHEC scenario and 373 million USD for the Cochrane scenario, by averting 19 million and 54.5 million RTI sick days, respectively, compared to no probiotics. Antibiotic prescriptions decreased with 1.39-2.16 million courses, whereas absence from work decreased by 3.58-4.2 million days when applying the YHEC and Cochrane data, respectively. When productivity loss is included, total savings for society represented 784 million or 1.4 billion USD for the YHEC and Cochrane scenarios, respectively. Subgroup analyses demonstrated an incremental benefit of probiotics in at-risk groups, which might be of relevance for targeted interventions. Sensitivity analyses confirmed the robustness of the model outcomes. Our analysis demonstrated a positive impact of probiotics on the health care and economic burden of flu-like RTIs. Improved disease outcomes translated into considerable cost savings for both the payer and society.

Unsupervised extraction of epidemic syndromes from participatory influenza surveillance self-reported symptoms

Seasonal influenza surveillance is usually carried out by sentinel general practitioners (GPs) who compile weekly reports based on the number of influenza-like illness (ILI) clinical cases observed among visited patients. This traditional practice for surveillance generally presents several issues, such as a delay of one week or more in releasing reports, population biases in the health-seeking behaviour, and the lack of a common definition of ILI case. On the other hand, the availability of novel data streams has recently led to the emergence of non-traditional approaches for disease surveillance that can alleviate these issues. In Europe, a participatory web-based surveillance system called Influenzanet represents a powerful tool for monitoring seasonal influenza epidemics thanks to aid of self-selected volunteers from the general population who monitor and report their health status through Internet-based surveys, thus allowing a real-time estimate of the level of influenza circulating in the population. In this work, we propose an unsupervised probabilistic framework that combines time series analysis of self-reported symptoms collected by the Influenzanet platforms and performs an algorithmic detection of groups of symptoms, called syndromes. The aim of this study is to show that participatory web-based surveillance systems are capable of detecting the temporal trends of influenza-like illness even without relying on a specific case definition. The methodology was applied to data collected by Influenzanet platforms over the course of six influenza seasons, from 2011-2012 to 2016-2017, with an average of 34,000 participants per season. Results show that our framework is capable of selecting temporal trends of syndromes that closely follow the ILI incidence rates reported by the traditional surveillance systems in the various countries (Pearson correlations ranging from 0.69 for Italy to 0.88 for the Netherlands, with the sole exception of Ireland with a correlation of 0.38). The proposed framework was able to forecast quite accurately the ILI trend of the forthcoming influenza season (2016-2017) based only on the available information of the previous years (2011-2016). Furthermore, to broaden the scope of our approach, we applied it both in a forecasting fashion to predict the ILI trend of the 2016-2017 influenza season (Pearson correlations ranging from 0.60 for Ireland and UK, and 0.85 for the Netherlands) and also to detect gastrointestinal syndrome in France (Pearson correlation of 0.66). The final result is a near-real-time flexible surveillance framework not constrained by any specific case definition and capable of capturing the heterogeneity in symptoms circulation during influenza epidemics in the various European countries.

Culture-positive shigellosis cases are epidemiologically different to culture-negative/PCR-positive cases

OBJECTIVE

To review the epidemiological differences between culture-positive and culture-negative (but ipaH PCR-positive) cases of shigellosis in Sydney Local Health District (SLHD), NSW, to inform whether changes to the national case definition for shigellosis are required.

METHODS

An audit of all cases of shigellosis (culture-positive vs. culture-negative/PCR-positive) in SLHD from 1 January 2013 to 30 June 2015 was conducted and demographic, clinical and risk factors were analysed and compared between these groups.

RESULTS

Of the 148 shigellosis cases notified to SLHD, 122 cases (85 culture-positive vs. 37 culture-negative) were included for analysis. Culture-positive cases were more likely than culture-negative/PCR-positive cases to have experienced at least three symptoms (OR 3.18, 95%CI 1.3-7.5), been hospitalised (OR 4.2, 95%CI 1.4-13.2), and have had men-who-have-sex-with-men exposure identified as the source of their infection (OR 28.7, 95%CI 6.2-132.6).

CONCLUSIONS

This study has identified that culture-positive vs. culture-negative/PCR-positive shigellosis cases in NSW differ by clinical severity and risk factors for infection. Implications for public health: The study findings warrant further research to determine the true diagnostic prevalence of Shigella in the culture-negative/PCR-positive group in the Australian context, in order to inform further changes to the national case definition for shigellosis.

Climatic factors and long-term trends of influenza-like illness rates in The Netherlands, 1970-2016

BACKGROUND

Climatic factors affect the survival and transmissibility of respiratory viruses causing influenza-like illness (ILI), and we hypothesized that changes in absolute humidity and temperature may affect long-term trends of ILI incidence rate in temperate countries. We tested this hypothesis using ILI and meteorological time series in the Netherlands for the period 1970-2016.

METHODS

We described the long-term trends of ILI incidence, absolute humidity and temperature; modelled the association between climatic factors and ILI activity using negative binomial regression models; and assessed the strength of the association between the seasonal average absolute humidity (or temperature) and ILI incidence rate using the Spearman's rank correlation coefficient.

RESULTS

The ILI incidence rate declined from 1970 and reached a minimum in the season 2002-03, but started to increase again from the season 2003-04 onwards. In the negative binominal regression models, the weekly ILI count was inversely associated (p < 0.001) with 0- and 1-week lagged absolute humidity and temperature. After three decades of rising absolute humidity and temperature (1970-2000), the early 2000s represented a trend-reversal point for the climatic time series. The seasonal average ILI incidence rate and absolute humidity (or temperature) were strongly (inversely) correlated.

CONCLUSIONS

Our findings suggest that climate change may have played a role in the long-term trends of ILI incidence rates in the Netherlands, as we were able to show that lower humidity and temperature in a given week were associated with higher ILI incidence in the next week, there was a clear time point reversal in climatic parameters and ILI rates in the 2000s, and the average annual ILI incidence was inversely related to average annual temperatures and humidity.

Research Ethics in the European Influenzanet Consortium: Scoping Review

Background

Influenzanet was launched in several European countries to monitor influenza-like illness during flu seasons with the help of volunteering participants and Web-based technologies. As in the case of developing fields, ethical approaches are not well developed in the collection, processing, and analysis of participants’ information. Existing controversies and varying national ethical regulations can, thus, hamper efficient cross-border research collaboration to the detriment of quality disease surveillance.

Objective

This scoping review characterizes current practices on how ethical, legal, and social issues (ELSIs) pertinent to research ethics are handled by different Influenzanet country groups to analyze similarities and identify the need for further harmonization of ethical approaches.

Methods

A literature search was carried out on PubMed, Web of Science, Global Digital Library on Ethics, and Bioethics Literature Database to identify ELSIs for Influenzanet country platforms. Only English-language papers were included with publication dates from 2003 to 2017. Publications were screened for the application of bioethics principles in the implementation of country platforms. Additional publications gathered from the Influenzanet Consortium website, reference screening, and conference proceeding were screened for ELSIs.

Results

We gathered 96 papers from our search methodology. In total, 28 papers that mentioned ELSIs were identified and included in this study. The Research Ethics Committee (REC) approvals were sought for recruiting participants and collecting their data in 8 of 11 country platforms and informed e-consent was sought from participants in 9 of 11 country platforms. Furthermore, personal data protection was ensured throughout the Consortium using data anonymization before processing and analysis and using aggregated data.

Conclusions

Epidemics forecasting activities, such as Influenzanet, are beneficial; however, its benefits could be further increased through the harmonization of data gathering and ethical requirements. This objective is achievable by the Consortium. More transparency should be promoted concerning REC-approved research for Influenzanet-like systems. The validity of informed e-consent could also be increased through the provision of a user friendly and standard information sheet across the Consortium where participants agree to its terms, conditions, and privacy policies before being able to fill in the questionnaire. This will help to build trust in the general public while preventing any decline in participation.

Self-Swabbing for Virological Confirmation of Influenza-Like Illness Among an Internet-Based Cohort in the UK During the 2014-2015 Flu Season: Pilot Study

Background

Routine influenza surveillance, based on laboratory confirmation of viral infection, often fails to estimate the true burden of influenza-like illness (ILI) in the community because those with ILI often manage their own symptoms without visiting a health professional. Internet-based surveillance can complement this traditional surveillance by measuring symptoms and health behavior of a population with minimal time delay. Flusurvey, the UK’s largest crowd-sourced platform for surveillance of influenza, collects routine data on more than 6000 voluntary participants and offers real-time estimates of ILI circulation. However, one criticism of this method of surveillance is that it is only able to assess ILI, rather than virologically confirmed influenza.

Objective

We designed a pilot study to see if it was feasible to ask individuals from the Flusurvey platform to perform a self-swabbing task and to assess whether they were able to collect samples with a suitable viral content to detect an influenza virus in the laboratory.

Methods

Virological swabbing kits were sent to pilot study participants, who then monitored their ILI symptoms over the influenza season (2014-2015) through the Flusurvey platform. If they reported ILI, they were asked to undertake self-swabbing and return the swabs to a Public Health England laboratory for multiplex respiratory virus polymerase chain reaction testing.

Results

A total of 700 swab kits were distributed at the start of the study; from these, 66 participants met the definition for ILI and were asked to return samples. In all, 51 samples were received in the laboratory, 18 of which tested positive for a viral cause of ILI (35%).

Conclusions

This demonstrated proof of concept that it is possible to apply self-swabbing for virological laboratory testing to an online cohort study. This pilot does not have significant numbers to validate whether Flusurvey surveillance accurately reflects influenza infection in the community, but highlights that the methodology is feasible. Self-swabbing could be expanded to larger online surveillance activities, such as during the initial stages of a pandemic, to understand community transmission or to better assess interseasonal activity.

Prevalence, perception and correlates of low back pain among healthcare workers in tertiary health institutions in Sokoto, Nigeria

BACKGROUND

Low back pain (LBP) is a common cause of disability worldwide. Healthcare workers are particularly prone to it because of the physical and emotional factors associated with their profession.

OBJECTIVES

To determine the prevalence, perception and correlates of LBP among healthcare workers in tertiary health institutions in Sokoto, Nigeria.

METHODS

A cross-sectional study was conducted among 320 healthcare workers selected by multistage sampling technique from July to September 2016. Anthropometry was done for the participants in addition to questionnaire administration.

RESULTS

The mean age of the study participants was 36.99 ± 8.23 years. The lifetime, annual, and point prevalence of LBP among the participants were 56.2%, 39.1% and 17.2% respectively. Most, 151 (83.9%) of the 180 participants that have ever experienced LBP reported that it commenced after starting work, and they perceived it to be due to standing for long hours (57.2%), awkward postures (22.2%) and carrying heavy objects/patients at work (20.6%). Older age, female sex, longer duration of practice, overweight/obesity, and lifting heavy objects/patients at work were significantly associated with LBP among the participants.

CONCLUSION

The prevalence of LBP is high among healthcare workers in Sokoto, Nigeria; although it was also associated with older age and female sex, being in practice for 10 years and above, overweight/obesity, and lifting heavy objects/patients at work were the predictors identified. Management of the respective hospitals should prevent workplace exposures to heavy weight/objects by establishing "lift teams" as a temporary measure, and also implement "zero lift programs" in their facilities.

FUNDING

Nil.

Influenzanet: Citizens Among 10 Countries Collaborating to Monitor Influenza in Europe

Background

The wide availability of the Internet and the growth of digital communication technologies have become an important tool for epidemiological studies and health surveillance. Influenzanet is a participatory surveillance system monitoring the incidence of influenza-like illness (ILI) in Europe since 2003. It is based on data provided by volunteers who self-report their symptoms via the Internet throughout the influenza season and currently involves 10 countries.

Objective

In this paper, we describe the Influenzanet system and provide an overview of results from several analyses that have been performed with the collected data, which include participant representativeness analyses, data validation (comparing ILI incidence rates between Influenzanet and sentinel medical practice networks), identification of ILI risk factors, and influenza vaccine effectiveness (VE) studies previously published. Additionally, we present new VE analyses for the Netherlands, stratified by age and chronic illness and offer suggestions for further work and considerations on the continuity and sustainability of the participatory system.

Methods

Influenzanet comprises country-specific websites where residents can register to become volunteers to support influenza surveillance and have access to influenza-related information. Participants are recruited through different communication channels. Following registration, volunteers submit an intake questionnaire with their postal code and sociodemographic and medical characteristics, after which they are invited to report their symptoms via a weekly electronic newsletter reminder. Several thousands of participants have been engaged yearly in Influenzanet, with over 36,000 volunteers in the 2015-16 season alone.

Results

In summary, for some traits and in some countries (eg, influenza vaccination rates in the Netherlands), Influenzanet participants were representative of the general population. However, for other traits, they were not (eg, participants underrepresent the youngest and oldest age groups in 7 countries). The incidence of ILI in Influenzanet was found to be closely correlated although quantitatively higher than that obtained by the sentinel medical practice networks. Various risk factors for acquiring an ILI infection were identified. The VE studies performed with Influenzanet data suggest that this surveillance system could develop into a complementary tool to measure the effectiveness of the influenza vaccine, eventually in real time.

Conclusions

Results from these analyses illustrate that Influenzanet has developed into a fast and flexible monitoring system that can complement the traditional influenza surveillance performed by sentinel medical practices. The uniformity of Influenzanet allows for direct comparison of ILI rates between countries. It also has the important advantage of yielding individual data, which can be used to identify risk factors. The way in which the Influenzanet system is constructed allows the collection of data that could be extended beyond those of ILI cases to monitor pandemic influenza and other common or emerging diseases.