Objective: To assess the utility of a test-based approach to shorten isolation of healthcare workers with COVID-19 in the setting of the highly transmissible omicron variant Methods: Between December 24th, 2021, to January 5th, 2022 HCWs who tested positive for SARS-CoV-2 were re-tested at least five days since onset of symptoms. Results: 46 sequential fully COVID-19 vaccinated HCWs who had tested positive for SARS-CoV-2 underwent follow up testing. All the isolates were confirmed as omicron variants and only 4 (8.7%) were negative 5 days or more since onset of symptoms., Conclusions: Implementation of a test-based strategy is logistically challenging, increases costs and did not lead to shorter isolation in our institution.
We evaluated uptake and factors associated with COVID-19 vaccination among health workers (HWs) in Azerbaijan. Among 1,575 HWs, 73% had received at least one dose and 67% received two doses; all received CoronaVac. Factors associated with vaccination uptake included no previous COVID-19 infection, older age, belief in the vaccine’s safety, previous vaccination for influenza, having patient-facing roles, and good or excellent health by self-assessment. These findings could inform strategies to increase vaccination uptake as the campaign continues.
Respiratory syncytial virus (RSV) is the leading cause of severe lower respiratory infection and therefore, a major threat to global health. In the Philippines, RSV is the second most common respiratory viral pathogen next to rhinovirus among children with severe pneumonia. Since 2006, national influenza-like illness (ILI) and severe acute respiratory infection (SARI) surveillances have been mainly focused only on influenza viruses. The prevalence and genetic diversity of RSV in the last decades were not completely elucidated. This study determined the epidemiological and molecular characteristics of RSV among (ILI) and (SARI) cases of children in the Philippines. The Philippine National Influenza Centre (PNIC) collected oropharyngeal swab and nasopharyngeal swab samples from patients under the age of five who are presented with ILI and SARI for the period of 2006-2016. These swabs have been examined for RSV subgroup by multiplex real-time qRT-PCR. Sequencing and phylogenetic analyses were used to determine the genotype of RSV samples. A total of 1,036 samples were systematically selected and tested. Of these samples, 122 were RSV-positive at 11.8 % prevalence rate, and 58.2% (71/122) were classified as RSV-A. Six genotypes were identified, which included NA1 (27/122, 22.1%), ON1 (5/122, 4.1%), GA2 (1/122, 0.8%) and GA5 (1/123, 0.8%) for RSV-A; and BA2 (13/122, 10.7%) and BA9 (1/122, 0.8%) for RSV-B. Most RSV-related cases were significantly associated with pneumonia and bronchitis. The pattern of RSV activity in the Philippines resembles the transmission of RSV globally.
Background: In France, each year, influenza viruses are responsible for seasonal epidemics leading to 2-6 million cases. Influenza can cause severe disease that may lead to hospitalization or death. As severe disease may be due to the virus itself or to disease complications, estimating the burden of severe influenza is complex. The present study aimed at estimating the epidemiological and economic burden of severe influenza in France during eight consecutive influenza seasons (2010-2018). Methods: Influenza-related hospitalization and mortality data and patient characteristics were taken from the French hospital information database, PMSI. An ecological approach using cyclic regression models integrating the incidence of influenza syndrome from the Sentinelles Network supplemented the PMSI data analysis in estimating excess hospitalization and mortality (CépiDc – 2010-2015) and medical costs. Results: Each season, the average number of influenza-related hospitalizations was 18,979 (range: 8,627-44,024), with an average length of stay of 8 days. The average number of respiratory hospitalizations indirectly related with influenza (i.e., influenza-associated) was 31,490 (95% CI: 24,542-39,012), with an average cost of \euro141 million (range: 54-217); 70% of these hospitalizations and 77% of their costs concerned individuals ≥ 65 years of age (65+). More than 90% of excess mortality was in 65+ subjects. Conclusions: The combination of two complementary approaches allowed estimation of both influenza-related and associated hospitalizations and deaths and their burden in France, showing the substantial impact of complications. The present study highlighted the major public health burden of influenza and its severe complications, especially in 65+ subjects.
Background: While the high burden of illness caused by seasonal influenza in children and the elderly is well-recognized, 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 vaccination 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 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 included. Reported hospitalization rates associated with laboratory-confirmed influenza 5.7 to 112.8 per 100,000. Rates tended to be higher in 2015-2019 compared to 2010-2014, 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 0.8-3.5 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 in 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 policy.
Background: Human respiratory syncytial virus (HRSV) is a major cause of severe viral acute respiratory illness and contributes significantly to severe pneumonia cases in Africa. Little is known about its spatial-temporal distribution as defined by its genetic diversity. Methods: A retrospective study conducted utilizing archived nasopharyngeal specimens from patients attending outpatient clinics in hospitals located in five demographically and climatically distinct regions of Kenya; Coast, Western, Highlands, Eastern and Nairobi. The viral total RNA was extracted and tested using multiplex real time RT-PCR (reverse transcriptase polymerase chain reaction). A segment of the G-gene was amplified using one-step RT-PCR and sequenced by Sanger di-deoxy method. Bayesian analysis of phylogeny was utilized and subsequently median joining methods for haplotype network reconstruction. Results: Three genotypes of HRSVA were detected; GA5 (14.0%), GA2 (33.1%) and NA1 (52.9%). HRSVA prevalence varied by location from 33% to 13.2% in the Highlands and the Eastern regions respectively. The mean nucleotide diversity (Pi(π)) varied by genotype: highest of 0.018 for GA5 and lowest of 0.005 for NA1. A total of 58 haplotypes were identified (GA5 10; GA2 20; NA1 28). These haplotypes were introduced into the population locally by single haplotypes and additional subsidiary seeds amongst the GA2 and the NA1 haplotypes. Conclusions: HRSVA was found across all the regions throughout the study period and comprised three genotypes; GA5, GA2 and NA1 genotypes. The genotypes were disproportionately distributed across the regions with GA5 gradually increasing towards the Western zones and decreasing towards the Eastern zones of the country.
Background: Data on disease burden of respiratory syncytial virus (RSV) associated acute lower respiratory infection (ALRI) among young children are limited in China. This study aimed to estimate the hospitalization rate of RSV-associated ALRI (RSV-ALRI) among children aged 0~59 months in Suzhou, China. Methods: We retrospectively identified all hospitalized ALRI children aged 0~59 months in Suzhou University Affiliated Children’s Hospital during January 2010 to December 2014. Detailed diagnosis and treatment data were collected by individual medical chart review. Referring to WHO influenza disease burden estimation method, we estimated the hospitalization rate of RSV-ALRI among children aged 0~59 months in Suzhou, China. Results: Among 28,209 ALRI cases, 19,317 (68.5%) were tested for RSV and the RSV positive proportion was 21.3% (4,107/19,317). The average hospitalization rate of RSV-ALRI for children aged 0~59 months was 14 (95% confidence interval [CI]:14~14)/1,000 children-years, for children aged 0~5, 6~11, 12~23, and 24~59 months were 70 (95%CI: 67~73), 31 (95%CI: 29~33), 11 (95%CI: 10~12), and 3 (95%CI: 3~3) /1,000 children-years, respectively. Conclusion: There is considerable RSV-ALRI hospitalization among children aged 0~59 months, particularly among children aged <1 years. An effective monoclonal antibody or vaccine is urgently needed to address the substantial hospitalization burden owing to RSV infection. Key words: Respiratory syncytial virus, Hospitalization rate, Acute lower respiratory infection, Children, China
Background. We sought to evaluate the impact of changes in estimates of COVID-19 vaccine effectiveness on the incidence of laboratory-confirmed infection among frontline workers at high risk for SARS-CoV-2. Methods. We analyzed data from a prospective frontline worker cohort to estimate the incidence of COVID-19 by month as well as the association of COVID-19 vaccination, occupation, demographics, physical distancing and mask use with infection risk. Participants completed baseline and quarterly surveys, and each week self-collected mid-turbinate nasal swabs and reported symptoms. Results. Among 1,018 unvaccinated and 3,531 fully vaccinated workers, the monthly incidence of laboratory-confirmed SARS-CoV-2 infection in January 2021 was 13.9 (95% confidence interval [CI]: 10.4-17.4), declining to 0.5 (95% CI -0.4-1.4) per 1000 person-weeks in June. By September 2021, when the Delta variant predominated, incidence had once again risen to 13.6 (95% CI 7.8-19.4) per 1000 person-weeks. In contrast, there was no reportable incidence among fully vaccinated participants at the end of January 2021, and incidence remained low until September 2021 when it rose modestly to 4.1 (95% CI 1.9-3.8) per 1000. Below average facemask use was associated with a higher risk of infection for unvaccinated participants during exposure to persons who may have COVID-19, and vaccinated participants during hours in the community. Conclusions. COVID-19 vaccination was significantly associated with a lower risk of SARS-CoV-2 infection despite Delta variant predominance. Our data demonstrate the added protective benefit of facemask use among both unvaccinated and vaccinated frontline workers.
Background Estimates of the disease burden associated with different respiratory viruses are severely limited in low- and middle-income countries, especially in Africa. Methods We estimated age-specific numbers and rates of medically and non-medically attended influenza-like illness (ILI) and severe respiratory illness (SRI) that were associated with influenza, respiratory syncytial virus (RSV), rhinovirus, human metapneumovirus, adenovirus, enterovirus and parainfluenza virus types 1-3 after adjusting for the attributable fraction (AF) of virus detection to illness in South Africa during 2013-2015. Rates were reported per 100,000 population. Results The mean annual rates were 51,383 and 4,196 for ILI and SRI, respectively. Of these, 26% (for ILI) and 46% (for SRI) were medically attended. Among outpatients with ILI, rhinovirus had the highest AF-adjusted rate (7,221), followed by influenza (6,443) and adenovirus (1,364); whereas, among inpatients with SRI, rhinovirus had the highest AF-adjusted rate (400), followed by RSV (247) and influenza (130). Rhinovirus (9,424) and RSV (2,026) had the highest AF-adjusted rates among children aged <5 years with ILI or SRI, respectively; whereas rhinovirus (757) and influenza (306) had the highest AF-adjusted rates among individuals aged ≥65 years with ILI or SRI, respectively Conclusions There was a substantial burden of ILI and SRI in South Africa during 2013-2015. Rhinovirus and influenza had a prominent disease burden among patients with ILI. Rhinovirus had the highest burden of illness among patients of any age with SRI, followed by RSV. RSV and influenza were the most prominent causes of SRI in children and the elderly, respectively.
Background: In response to the coronavirus disease (COVID-19) outbreak that unfolded across Europe in 2020, the World Health Organisation called for repurposing existing influenza surveillance systems to monitor COVID-19. This analysis aimed to compare descriptively the extent to which influenza surveillance systems were adapted and enhanced, and how COVID-19 surveillance could ultimately benefit or disrupt routine influenza surveillance. Methods: We used a previously developed framework in France, Germany, Italy, Spain and the United Kingdom to describe COVID-19 surveillance and its impact on influenza surveillance. The framework divides surveillance systems into 7 sub-systems and 20 comparable outcomes of interest, and uses 5 evaluation criteria based on WHO guidance. Information on influenza and COVID-19 surveillance systems were collected from publicly available resources shared by European and national public health agencies. Results: Overall, non-medically attended, virological, primary care and mortality surveillance were adapted in most countries to monitor COVID-19, whilst community, outbreak, and hospital surveillance were reinforced in all countries. Data granularity improved, with more detailed demographic and medical information recorded. A shift to systematic notification for cases and deaths enhanced both geographic and population representativeness whilst the sampling strategy benefited from the roll out of widespread molecular testing. Data communication was greatly enhanced, contributing to improved public awareness. Conclusions: Well-established influenza surveillance systems are a key component of pandemic preparedness and their upgrade allowed European countries to respond to the COVID-19 pandemic. However, uncertainties remain on how both influenza and COVID-19 surveillance can be jointly and durably implemented.
INTRODUCTION. Respiratory syncytial virus (RSV) is the major cause of lower respiratory tract illness in young children and can also cause influenza-like illness (ILI). Here we investigated the epidemiological features of RSV infection in pediatric ILI cases in Lombardy (a region in Northern Italy accounting nearly 10-million inhabitants) from 2014-2015 to 2020-2021 winter seasons. MATERIAL AND METHODS. Data for this study were retrieved and statistically analyzed from the database of virological influenza surveillance of the regional reference laboratory for Lombardy within the Italian influenza surveillance network (InfluNet). RESULTS. RSV accounting for nearly 19% of pediatric ILI with a risk of infection nearly 2-fold greater than that of individuals ≥15 years. The RSV positivity rate increased to 28% considering 0-5 years old children. Although in children ≤5 years the risk of infection from influenza viruses resulted nearly 2-fold higher than the risk of RSV infection, the age group 4-6 months and 7-12 months showed 5-fold greater risk of infection from RSV than from influenza. Children ≤5 years of age with presence of one or more comorbidities had a nearly 5-fold greater risk of getting RSV infection than otherwise healthy 0-5 years old children. DISCUSSION. The use of the ILI sentinel surveillance allowed us to identify groups at higher risk of RSV and influenza infection and to define the start, duration, timing and intensity of the RSV and influenza community circulation, determining thresholds based on historical data. This surveillance approach can be implemented to assess the nearly real-time RSV circulation and impact.
In March 2021, Lao People’s Democratic Republic (Laos) reported an avian influenza A(H5N6) virus infection in a 5-year-old child identified through sentinel surveillance. This was the first human A(H5N6) infection reported outside of China. A multidisciplinary investigation undertook contact tracing and enhanced human and animal surveillance in surrounding villages and live bird markets. Seven Muscovy ducks tested positive for highly pathogenic avian influenza A(H5N6) viruses. Sequenced viruses belonged to clade 126.96.36.199h and were closely related to viruses detected in poultry in Vietnam, and to previous viruses detected in Laos. Surveillance and coordinated outbreak response remain essential to global health security.
Stringent public health measures imposed across Canada to control the COVID-19 pandemic have nearly suppressed most seasonal respiratory viruses, with the notable exception of human rhinovirus/enterovirus (hRV/EV). Thanks to this unexpected persistence, we highlight that hRV/EV could serve as a sentinel for levels of contact rate in populations to inform on the efficiency¬, or the need of, public health measures to control the subsequent COVID-19 epidemic, but also for future epidemics from other seasonal or emerging respiratory pathogens.
Background: reliable country-specific data on influenza burden play a crucial role in informing prevention and control measures. Our purpose was to provide a comprehensive summary of the available evidence on the burden of seasonal influenza in Italy. Methods: we performed a sys-tematic literature review of articles published until 31 July 2020. PubMed, Embase and Web of Science were searched using terms related to burden, influenza, and Italian population. We in-cluded studies investigating seasonal influenza-related complications, hospitalizations and/or mortality. Results: sixteen studies were included: eight (50%) analyzed influenza-related compli-cations, eight (50%) hospitalizations, while seven (43.8%) influenza-related deaths. Only three studies (19.7%) concerned pediatric age. The synthesis of results showed that patients with chron-ic conditions have an increased risk for complications up to almost three times as compared to healthy people. Hospitalizations due to influenza can occur in as much as 5% of infected people depending on the study setting. Excess deaths rates were over six-fold higher in the elderly as compared to the rest of population. Conclusions: although there are still gaps in existing data, there is evidence of the significant burden that influenza places each year especially on high-risk groups. These data should be used to inform public health decision-making.
Background: The COVID-19 pandemic has highlighted the need for targeted local interventions given substantial heterogeneity within cities and counties. Publicly available case data are typically aggregated to the city or county level to protect patient privacy, but more granular data are necessary to identify and act upon community-level risk factors that can change over time. Methods: Individual COVID-19 case and mortality data from Massachusetts were geocoded to residential addresses and aggregated into two time periods: “Phase 1” (March–June 2020) and “Phase 2” (September 2020–February 2021). Institutional cases associated with long-term care facilities, prisons, or homeless shelters were identified using address data and modeled separately. Census tract sociodemographic and occupational predictors were drawn from the 2015-2019 American Community Survey. We used mixed-effects negative binomial regression to estimate incidence rate ratios (IRRs), accounting for town-level spatial autocorrelation. Results: Case incidence was elevated in census tracts with higher proportions of Black and Latinx residents, with larger associations in Phase 1 than Phase 2. Case incidence associated with proportion of essential workers was similarly elevated in both Phases. Mortality IRRs had differing patterns from case IRRs, decreasing less substantially between Phases for Black and Latinx populations and increasing between Phases for proportion of essential workers. Mortality models excluding institutional cases yielded stronger associations for age, race/ethnicity, and essential worker status. Conclusions: Geocoded home address data can allow for nuanced analyses of community disease patterns, identification of high-risk subgroups, and exclusion of institutional cases to comprehensively reflect community risk.
Introduction: We describe epidemiology and outcomes of confirmed SARS-CoV-2 infection and admissions among children <18 years in South Africa, an upper-middle income setting with high inequality. Methods: Laboratory and hospital COVID-19 surveillance data, 28 January - 19 September 2020 was used. Testing rates were calculated as number of tested for SARS-CoV-2 divided by population at risk; test positivity rates were calculated as positive tests divided by total number of tests. In-hospital case fatality ratio (CFR) was calculated based on hospitalized positive admissions with outcome data who died in-hospital and death was judged SARS-CoV-2 related by attending physician. Findings: 315,570 children aged <18 years were tested for SARS-CoV-2; representing 8.9% of all 3,548,738 tests and 1.6% of all children in the country. Of children tested, 46,137 (14.6%) were positive. Children made up 2.9% (n=2,007) of all SARS-CoV-2 positive admissions to sentinel hospitals. Among children, 47 died (2.6% case-fatality). In-hospital deaths were associated with male sex [adjusted odds ratio (aOR) 2.18 (95% confidence intervals (CI) 1.08 - 4.40)] vs female; age <1 year [aOR 4.11 (95% CI 1.08-15.54)], age 10-14 years [aOR 4.20 (95% CI1.07-16.44)], age 15-17 years [aOR 4.86 (95% 1.28 -18.51)] vs age 1-4 years; admission to a public hospital [aOR 5.07(95% 2.01 -12.76)] vs private hospital and ≥1 underlying conditions [aOR 12.09 (95% CI 4.19-34.89)] vs none Conclusions: Children with underlying conditions were at greater risk of severe SARS-CoV-2 outcomes. Children > 10 years and those with underlying conditions should be considered for increased testing and vaccination.
Background Zanamivir is a neuraminidase inhibitor effective against influenza A and B viruses. In 2009, GlaxoSmithKline (GSK) began clinical development of intravenous (IV) zanamivir, and initiated a global Compassionate Use Program (CUP) in response to the evolving H1N1 global pandemic. The goal of the CUP was to provide zanamivir to critically ill patients with limited treatment options. Methods Zanamivir was administered to patients with suspected or confirmed influenza infection, who were not suitable for other approved antiviral treatments. Reporting of serious adverse events (SAEs) was mandatory and recorded in the GSK safety database. A master summary tracking sheet captured requests and patient characteristics. A case report form was available for detailing medical conditions, dosing, treatment duration, and clinical outcomes. Results In total, 4033 requests were made for zanamivir treatment of hospitalized patients from 38 countries between 2009 and 2019. Europe had the highest number of requests (n=3051) followed by North America (n=713). At least 20 patients were aged ≤6 months, of whom 12 were born prematurely. The GSK safety database included 466 patients with ≥1 SAE, of whom 374 (80%) had a fatal outcome. Drug-related SAEs were reported in 41 (11%) patients, including hepatic failure (n=6 [2%]) and acute kidney injury (n=5 [1%)]. Conclusions The CUP fulfilled the need to provide global access to zanamivir prior to product approval. No new safety concerns were identified in the CUP compared with IV zanamivir clinical studies.
Background. In the United States, infection with SARS-CoV-2 caused 380,000 reported deaths from March to December 2020. Methods. We adapted the Moving Epidemic Method to all-cause mortality data from the United States to assess the severity of the COVID-19 pandemic across age groups and all 50 states. By comparing all-cause mortality during the pandemic with intensity thresholds derived from recent, historical all-cause mortality, we categorized each week from March to December 2020 as either low severity, moderate severity, high severity, or very high severity. Results. Nationally for all ages combined, all-cause mortality was in the very high severity category for 9 weeks. Among people 18 to 49 years of age, there were 29 weeks of consecutive very high severity mortality. Forty-seven states, the District of Columbia, and New York City each experienced at least one week of very high severity mortality for all ages combined. Conclusions. These periods of very high severity of mortality during March through December 2020 are likely directly or indirectly attributable to the COVID-19 pandemic. This method for standardized comparison of severity over time across different geographies and demographic groups provides valuable information to understand the impact of the COVID-19 pandemic and to identify specific locations or subgroups for deeper investigations into differences in severity.