Estimation of influenza and respiratory syncytial virus hospitalizations using sentinel surveillance data-La Paz, Bolivia. 2012-2017

The economic burden of viral severe acute respiratory infections in the Kingdom of Saudi Arabia: A nationwide cost-of-illness study

Objectives

The authors conducted a study to estimate the rising disease and economic burden of viral severe acute respiratory infections and their management, including COVID-19, respiratory syncytial virus, and influenza types A and B, in early and delayed diagnosis scenarios in the Kingdom of Saudi Arabia from a national perspective.

Methods

This cross-sectional study was conducted in May 2022 using a de novo Excel-based universal cost-of-illness calculator model. The study used primary data, such as expert interviews, as well as secondary data from a thorough literature search.

Results

The total economic burden of viral severe acute respiratory infections in patients with an early diagnosis was lower than those with a delayed diagnosis among patients with complications, both from the payer's (United States dollar [USD] 3846 million vs USD 4726 million) and societal (USD 4048 million vs USD 5020 million, respectively) perspectives. The major cost driver of the total economic burden for both early and delayed diagnosis was disease management costs: 49% (USD 1880 million) and 58% (USD 2730 million), respectively.

Conclusions

In the Kingdom of Saudi Arabia, the total economic burden for COVID-19, influenza (epidemic phase), and respiratory syncytial virus was higher with a delayed diagnosis vs an early diagnosis, emphasizing the importance of using a broader diagnostic method.

Year-to-year variation in attack rates could result in underpowered RSV vaccine efficacy trials

OBJECTIVE

Year-to-year variation of respiratory viruses may result in lower attack rates than expected. We aimed to illustrate the impact of year-to-year variation in attack rates on the likelihood of demonstrating vaccine efficacy (VE) .

STUDY DESIGN AND SETTING

We considered an individually randomized maternal vaccine trial against respiratory syncytial virus-associated hospitalisations (RSVH). For 10 RSVH per 1,000 infants, sample size to have 80% power for true VE of 50% and 70% was 9,846 and 4,424 participants. We reported power to show VE for varying attack rates, selected to reflect realistic year-to-year variation using observational studies. Eight scenarios including varying number of countries and seasons were developed to assess the influence of these trial parameters.

RESULTS

Including up to three seasons decreased the width of the interquartile range for power. Including more seasons concentrated statistical power closer to 80%. Least powered trials had higher statistical power with more seasons. In all scenarios, at least half of the trials had <80% power. For three-season trials, increasing the sample size by 10% reduced the percentage of underpowered trials to less than one-quarter of trials.

CONCLUSION

Year-to-year variation in RSV attack rates should be accounted for during trial design. Mitigation strategies include recruiting over more seasons, or adaptive trial designs.

Burden of severe illness associated with laboratory confirmed influenza in adults aged 50-64 years: A rapid review

BACKGROUND

While the high burden of illness caused by seasonal influenza in children and the elderly is well recognize, less is known about the burden in adults 50-64 years of age. The lack of data for this age group is a key challenge in evaluating the cost-effectiveness of immunization programs. We aimed to assess influenza-associated hospitalization and mortality rates and case fatality rates for hospitalized cases among adults aged 50-64 years.

METHODS

This rapid review was conducted according to the PRISMA; we searched MEDLINE, EMBASE, Cochrane, Web of Science, and grey literature for articles and reports published since 2010. Studies reporting rates of hospitalization and/or mortality associated with laboratory-confirmed influenza among adults 50-64 or 45-64 years of age for the 2010-11 through 2019-20 seasons were included.

RESULTS

Twenty studies from 13 countries were reviewed. Reported rates of hospitalization associated with laboratory-confirmed influenza were 5.7 to 112.8 per 100,000. Rates tended to be higher in the 2015-2019 compared with the 2010-2014 seasons and were higher in studies reporting data from high-income versus low and middle-income countries. Mortality rates were reported in only one study, with rates ranging from 0.8 to 3.5 per 100,000 in four different seasons. The case fatality rate among those hospitalized with influenza, as reported by population-based studies, ranged from 1.3% to 5.6%.

CONCLUSIONS

Seasonal influenza imposes a significant burden of morbidity on adults 50-64 years of age but with high heterogeneity across seasons and geographic regions. Ongoing surveillance is required to improve estimates of burden to better inform influenza vaccination and other public health policies.

Effects of mechanical ventilation on indoor air quality and occupant health status in energy-efficient homes: A longitudinal field study

Despite the growing interest in energy-efficient homes (EEHs), there is still a lack of evidence regarding whether the mechanical ventilation system of an EEH positively or negatively impacts indoor air quality (IAQ) and the health and wellbeing of occupants. This study aimed to evaluate the IAQ level and daily health symptoms of adults and children living in EEHs compared to conventional buildings over the course of one year. A two-way mixed analysis of variance was conducted to compare the level of IAQ between the two housing types. A binomial generalized linear mixed model (GLMM) and generalized additive mixed model was developed to investigate the association between IAQ and daily risks of symptoms. Differences in the daily prevalence of symptoms between the two housing types were assessed using a Poisson GLMM model. Overall, the indoor concentrations of particulate matter (PM₁₀ and PM_2.5), carbon dioxide (CO₂), and volatile organic compounds (VOCs) were lower in EEH after controlling for seasonality. The indoor temperature and relative humidity level were relatively constant in the EEH. We also found that an increased level of indoor air quality parameters, particularly CO_2, which is closely related to the indoor ventilation rate, was associated with the daily risk of eye fatigue, allergic rhinitis, and atopic dermatitis symptoms. Considering that EEH effectively reduced indoor air pollutants and IAQ improvement was associated with a reduction in the risk of individual symptoms, the IAQ improvement of EEH may have positively impacted occupants' health. Symptoms such as eye fatigue and skin dryness, which have been reported in previous studies as potential side effects of mechanical ventilation, were reported in this study; however, they were not found to be statistically significantly different from those reported in the conventional building.

Seasonal Influenza Prevention and Control Progress in Latin America and the Caribbean in the Context of the Global Influenza Strategy and the COVID-19 Pandemic

Each year in Latin America and the Caribbean, seasonal influenza is associated with an estimated 36,500 respiratory deaths and 400,000 hospitalizations. Since the 2009 influenza A(H1N1) pandemic, the Region has made significant advances in the prevention and control of seasonal influenza, including improved surveillance systems, burden estimates, and vaccination of at-risk groups. The Global Influenza Strategy 2019–2030 provides a framework to strengthen these advances. Against the backdrop of this new framework, the University of Colorado convened in October 2020 its Immunization Advisory Group of Experts to review and discuss current surveillance, prevention, and control strategies for seasonal influenza in Latin America and the Caribbean, also in the context of the COVID-19 pandemic. This review identified five areas for action and made recommendations specific to each area. The Region should continue its efforts to strengthen surveillance and impact evaluations. Existing data on disease burden, seasonality patterns, and vaccination effectiveness should be used to inform decision-making at the country level as well as advocacy efforts for programmatic resources. Regional and country strategic plans should be prepared and include specific targets for 2030. Existing investments in influenza prevention and control, including for immunization programs, should be optimized. Finally, regional partnerships, such as the regional networks for syndromic surveillance and vaccine effectiveness evaluation (SARInet and REVELAC-i), should continue to play a critical role in continuous learning and standardization by sharing experiences and best practices among countries.

Epidemiology and Seasonality of Childhood Respiratory Syncytial Virus Infections in the Tropics

Infections caused by respiratory syncytial virus (RSV) are a major cause of morbidity and mortality in young children worldwide. Understanding seasonal patterns of region-specific RSV activity is important to guide resource allocation for existing and future treatment and prevention strategies. The decades of excellent RSV surveillance data that are available from the developed countries of the world are incredibly instructive in advancing public health initiatives in those regions. With few exceptions, these developed nations are positioned geographically across temperate regions of the world. RSV surveillance across tropical regions of the world has improved in recent years, but remains spotty, and where available, still lacks the necessary longitudinal data to determine the amount of seasonal variation expected over time. However, existing and emerging data collected across tropical regions of the world do indicate that patterns of infection are often quite different from those so well described in temperate areas. Here, we provide a brief summary regarding what is known about general patterns of RSV disease activity across tropical Asia, Africa and South America, then offer additional country-specific details using examples where multiple reports and/or more robust surveillance data have become available.

Challenges in the prevention or treatment of RSV with emerging new agents in children from low- and middle-income countries

INTRODUCTION

Respiratory syncytial virus (RSV) causes approximately 120,000 deaths annually in children <5 years, with 99% of fatalities occurring in low- and middle-income countries (LMICs).

AREAS COVERED

There are numerous RSV interventions in development, including long-acting monoclonal antibodies, vaccines (maternal and child) and treatments which are expected to become available soon. We reviewed the key challenges and issues that need to be addressed to maximize the impact of these interventions in LMICs. The epidemiology of RSV in LMICs was reviewed (PubMed search to 30 June 2020 inclusive) and the need for more and better-quality data, encompassing hospital admissions, community contacts, and longer-term respiratory morbidity, emphasized. The requirement for an agreed clinical definition of RSV lower respiratory tract infection was proposed. The pros and cons of the new RSV interventions are reviewed from the perspective of LMICs.

EXPERT OPINION

We believe that a vaccine (or combination of vaccines, if practicable) is the only viable solution to the burden of RSV in LMICs. A coordinated program, analogous to that with polio, involving governments, non-governmental organizations, the World Health Organization, the manufacturers and the healthcare community is required to realize the full potential of vaccine(s) and end the devastation of RSV in LMICs.

Clinical features of the first cases and a cluster of Coronavirus Disease 2019 (COVID-19) in Bolivia imported from Italy and Spain

INTRODUCTION

In March 2020, Coronavirus Disease 2019 (COVID-19) arrived in Bolivia. Here, we report the main clinical findings, and epidemiological features of the first series of cases, and a cluster, confirmed in Bolivia.

METHODS

For this observational, retrospective and cross-sectional study, information was obtained from the Hospitals and the Ministry of Health for the cases that were laboratory-diagnosed and related, during March 2020. rRT-PCR was used for the detection of the RNA of SARS-CoV-2 following the protocol Charité, Berlin, Germany, from nasopharyngeal swabs.

RESULTS

Among 152 suspected cases investigated, 12 (7.9%) were confirmed with SARS-CoV-2 infected by rRT-PCR. The median age was 39 years (IQR 25-43), six of them male. Two cases proceed from Italy and three from Spain. Nine patients presented fever, and cough, five sore throat, and myalgia, among other symptoms. Only a 60 y-old woman with hypertension was hospitalized. None of the patients required ICU nor fatalities occurred in this group.

CONCLUSIONS

This is the first report of surveillance of COVID-19 in Bolivia, with patients managed mainly with home isolation. Preparedness for a significant epidemic, as is going on in other countries, and the deployment of response plans for it, in the country is now taking place to mitigate the impact of the COVID-19 pandemic in the population.

Estimation of influenza and respiratory syncytial virus hospitalizations using sentinel surveillance data-La Paz, Bolivia. 2012-2017

OBJECTIVE

The objective was to estimate the number of hospitalizations associated with influenza and RSV using data from severe acute respiratory infection (SARI) sentinel surveillance from El Alto-La Paz. Bolivia.

METHODS

All persons who met the case definition for SARI at one sentinel hospital had a clinical sample collected and analyzed by rRT-PCR for influenza and by indirect immunofluorescence for RSV. The SARI-influenza and SARI-RSV case counts were stratified by six age groups. The proportion of cases captured in the sentinel hospital in relation to the non-sentinel hospitals of area was multiplied by the age-specific census population, to build the denominators. The annual incidence and a 95% confidence interval (CI) were estimated.

RESULTS

During 2012-2017, n = 2606 SARI cases were reported (average incidence 120/100 000 inhabitants [95% CI: 116-124]); the average incidence of influenza-associated SARI hospitalization was 15.3/100 000 (95% CI: 14.1-16.7), and the average incidence of RSV-associated SARI hospitalization was 9/100 000 inhabitants (95% CI: 8.1-10.1). The highest incidence of influenza was among those less than one year of age (average 174.7/100 000 [range: 89.1-299.5]), followed by those one to four years of age (average 51.8/100 000 [range: 19.8-115.4]) and then those 65 years of age and older (average 47.7/100 000 [range: 18.8-117]). For RSV, the highest incidence was highest among those less than one year of age (231/100 000 [range: 119.9-322.9]).

CONCLUSION

Influenza and RSV represent major causes of hospitalization in La Paz, Bolivia-with the highest burden among children under one year of age. Our estimates support current prevention strategies in this age group.