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1.
MMWR Morb Mortal Wkly Rep ; 70(47): 1623-1628, 2021 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-34818320

RESUMO

Enterovirus D68 (EV-D68) is associated with a broad spectrum of illnesses, including mild to severe acute respiratory illness (ARI) and acute flaccid myelitis (AFM). Enteroviruses, including EV-D68, are typically detected in the United States during late summer through fall, with year-to-year fluctuations. Before 2014, EV-D68 was infrequently reported to CDC (1). However, numbers of EV-D68 detection have increased in recent years, with a biennial pattern observed during 2014-2018 in the United States, after the expansion of surveillance and wider availability of molecular testing. In 2014, a national outbreak of EV-D68 was detected (2). EV-D68 was also reported in 2016 via local (3) and passive national (4) surveillance. EV-D68 detections were limited in 2017, but substantial circulation was observed in 2018 (5). To assess recent levels of circulation, EV-D68 detections in respiratory specimens collected from patients aged <18 years* with ARI evaluated in emergency departments (EDs) or admitted to one of seven U.S. medical centers† within the New Vaccine Surveillance Network (NVSN) were summarized. This report provides a provisional description of EV-D68 detections during July-November in 2018, 2019 and 2020, and describes the demographic and clinical characteristics of these patients. In 2018, a total of 382 EV-D68 detections in respiratory specimens obtained from patients aged <18 years with ARI were reported by NVSN; the number decreased to six detections in 2019 and 30 in 2020. Among patients aged <18 years with EV-D68 in 2020, 22 (73%) were non-Hispanic Black (Black) persons. EV-D68 detections in 2020 were lower than anticipated based on the biennial circulation pattern observed since 2014. The circulation of EV-D68 in 2020 might have been limited by widespread COVID-19 mitigation measures; how these changes in behavior might influence the timing and levels of circulation in future years is unknown. Ongoing monitoring of EV-D68 detections is warranted for preparedness for EV-D68-associated ARI and AFM.

2.
Emerg Infect Dis ; 27(12): 3020-3029, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34477548

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections may be underestimated because of limited access to testing. We measured SARS-CoV-2 seroprevalence in South Africa every 2 months during July 2020-March 2021 in randomly selected household cohorts in 2 communities. We compared seroprevalence to reported laboratory-confirmed infections, hospitalizations, and deaths to calculate infection-case, infection-hospitalization, and infection-fatality ratios in 2 waves of infection. Post-second wave seroprevalence ranged from 18% in the rural community children <5 years of age, to 59% in urban community adults 35-59 years of age. The second wave saw a shift in age distribution of case-patients in the urban community (from persons 35-59 years of age to persons at the extremes of age), higher attack rates in the rural community, and a higher infection-fatality ratio in the urban community. Approximately 95% of SARS-CoV-2 infections were not reported to national surveillance.


Assuntos
COVID-19 , SARS-CoV-2 , Adulto , Criança , Humanos , Pessoa de Meia-Idade , População Rural , Estudos Soroepidemiológicos , África do Sul/epidemiologia
3.
Euro Surveill ; 26(29)2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34296675

RESUMO

BackgroundIn South Africa, COVID-19 control measures to prevent SARS-CoV-2 spread were initiated on 16 March 2020. Such measures may also impact the spread of other pathogens, including influenza virus and respiratory syncytial virus (RSV) with implications for future annual epidemics and expectations for the subsequent northern hemisphere winter.MethodsWe assessed the detection of influenza and RSV through facility-based syndromic surveillance of adults and children with mild or severe respiratory illness in South Africa from January to October 2020, and compared this with surveillance data from 2013 to 2019.ResultsFacility-based surveillance revealed a decline in influenza virus detection during the regular season compared with previous years. This was observed throughout the implementation of COVID-19 control measures. RSV detection decreased soon after the most stringent COVID-19 control measures commenced; however, an increase in RSV detection was observed after the typical season, following the re-opening of schools and the easing of measures.ConclusionCOVID-19 non-pharmaceutical interventions led to reduced circulation of influenza and RSV in South Africa. This has limited the country's ability to provide influenza virus strains for the selection of the annual influenza vaccine. Delayed increases in RSV case numbers may reflect the easing of COVID-19 control measures. An increase in influenza virus detection was not observed, suggesting that the measures may have impacted the two pathogens differently. The impact that lowered and/or delayed influenza and RSV circulation in 2020 will have on the intensity and severity of subsequent annual epidemics is unknown and warrants close monitoring.


Assuntos
COVID-19 , Vacinas contra Influenza , Influenza Humana , Infecções por Vírus Respiratório Sincicial , Vírus Sincicial Respiratório Humano , Adulto , Criança , Humanos , Influenza Humana/diagnóstico , Influenza Humana/epidemiologia , Influenza Humana/prevenção & controle , Pandemias/prevenção & controle , Infecções por Vírus Respiratório Sincicial/diagnóstico , Infecções por Vírus Respiratório Sincicial/epidemiologia , Infecções por Vírus Respiratório Sincicial/prevenção & controle , SARS-CoV-2 , África do Sul/epidemiologia
4.
Influenza Other Respir Viruses ; 15(6): 789-803, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34296810

RESUMO

PURPOSE: The PHIRST study (Prospective Household cohort study of Influenza, Respiratory Syncytial virus, and other respiratory pathogens community burden and Transmission dynamics in South Africa) aimed to estimate the community burden of influenza and respiratory syncytial virus (RSV) including the incidence of infection, symptomatic fraction, and to assess household transmission. PARTICIPANTS: We enrolled 1684 individuals in 327 randomly selected households in a rural and an urban site over three consecutive influenza and two RSV seasons. A new cohort of households was enrolled each year. Participants were sampled with nasopharyngeal swabs twice-weekly during the RSV and influenza seasons of the year of enrolment. Serology samples were collected at enrolment and before and after the influenza season annually. FINDINGS TO DATE: There were 122 113 potential individual follow-up visits over the 3 years, and participants were interviewed for 105 783 (87%) of these. Out of 105 683 nasopharyngeal swabs, 1258 (1%) and 1026 (1%) tested positive on polymerase chain reaction (PCR) for influenza viruses and RSV, respectively. Over one third of individuals had PCR-confirmed influenza each year. Overall, there was influenza transmission to 10% of household contacts of an index case. FUTURE PLANS: Future planned analyses include analysis of influenza serology results and RSV burden and transmission. Households enrolled in the PHIRST study during 2016-2018 were eligible for inclusion in a study of SARS-CoV-2 transmission initiated in July 2020. This study uses similar testing frequency to assess the community burden of SARS-CoV-2 infection and the role of asymptomatic infection in virus transmission.


Assuntos
COVID-19 , Influenza Humana , Infecções por Vírus Respiratório Sincicial , Vírus Sincicial Respiratório Humano , Estudos de Coortes , Humanos , Influenza Humana/epidemiologia , Estudos Prospectivos , Infecções por Vírus Respiratório Sincicial/epidemiologia , SARS-CoV-2 , África do Sul/epidemiologia
5.
BMC Public Health ; 21(1): 1055, 2021 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-34078327

RESUMO

BACKGROUND: Describing contact patterns is crucial to understanding infectious disease transmission dynamics and guiding targeted transmission mitigation interventions. Data on contact patterns in Africa, especially South Africa, are limited. We measured and compared contact patterns in a rural and urban community, South Africa. We assessed participant and contact characteristics associated with differences in contact rates. METHODS: We conducted a cross-sectional study nested in a prospective household cohort study. We interviewed participants to collect information on persons in contact with for one day. We described self-reported contact rates as median number people contacted per day, assessed differences in contact rates based on participant characteristics using quantile regression, and used a Poisson model to assess differences in contact rates based on contact characteristics within age groups. We also calculated cumulative person hours in contact within age groups at different locations. RESULTS: We conducted 535 interviews (269 rural, 266 urban), with 17,252 contacts reported. The overall contact rate was 14 (interquartile range (IQR) 9-33) contacts per day. Those ≤18 years had higher contact rates at the rural site (coefficient 17, 95% confidence interval (95%CI) 10-23) compared to the urban site, for those aged 14-18 years (13, 95%CI 3-23) compared to < 7 years. No differences were observed for adults. There was a strong age-based mixing, with age groups interacting more with similar age groups, but also interaction of participants of all ages with adults. Children aged 14-18 years had the highest cumulative person hours in contact (116.3 rural and 76.4 urban). CONCLUSIONS: Age played an important role in the number and duration of contact events, with children at the rural site having almost double the contact rate compared to the urban site. These contact rates can be utilized in mathematical models to assess transmission dynamics of infectious diseases in similar communities.


Assuntos
População Rural , Adulto , Criança , Estudos de Coortes , Estudos Transversais , Humanos , Estudos Prospectivos , África do Sul/epidemiologia , População Urbana
6.
Lancet Glob Health ; 9(6): e863-e874, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34019838

RESUMO

BACKGROUND: Data on influenza community burden and transmission are important to plan interventions especially in resource-limited settings. However, data are limited, particularly from low-income and middle-income countries. We aimed to evaluate the community burden and transmission of influenza in a rural and an urban setting in South Africa. METHODS: In this prospective cohort study approximately 50 households were selected sequentially from both a rural setting (Agincourt, Mpumalanga Province, South Africa; with a health and sociodemographic surveillance system) and an urban setting (Klerksdorp, Northwest Province, South Africa; using global positioning system data), enrolled, and followed up for 10 months in 2017 and 2018. Different households were enrolled in each year. Households of more than two individuals in which 80% or more of the occupants agreed to participate were included in the study. Nasopharyngeal swabs were collected twice per week from participating household members irrespective of symptoms and tested for influenza using real-time RT-PCR. The primary outcome was the incidence of influenza infection, defined as the number of real-time RT-PCR-positive episodes divided by the person-time under observation. Household cumulative infection risk (HCIR) was defined as the number of subsequent infections within a household following influenza introduction. FINDINGS: 81 430 nasopharyngeal samples were collected from 1116 participants in 225 households (follow-up rate 88%). 917 (1%) tested positive for influenza; 178 (79%) of 225 households had one or more influenza-positive individual. The incidence of influenza infection was 43·6 (95% CI 39·8-47·7) per 100 person-seasons. 69 (17%) of 408 individuals who had one influenza infection had a repeat influenza infection during the same season. The incidence (67·4 per 100 person-seasons) and proportion with repeat infections (22 [23%] of 97 children) were highest in children younger than 5 years and decreased with increasing age (p<0·0001). Overall, 268 (56%) of 478 infections were symptomatic and 66 (14%) of 478 infections were medically attended. The overall HCIR was 10% (109 of 1088 exposed household members infected [95% CI 9-13%). Transmission (HCIR) from index cases was highest in participants aged 1-4 years (16%; 40 of 252 exposed household members) and individuals with two or more symptoms (17%; 68 of 396 exposed household members). Individuals with asymptomatic influenza transmitted infection to 29 (6%) of 509 household contacts. HIV infection, affecting 167 (16%) of 1075 individuals, was not associated with increased incidence or HCIR. INTERPRETATION: Approximately half of influenza infections were symptomatic, with asymptomatic individuals transmitting influenza to 6% of household contacts. This suggests that strategies, such as quarantine and isolation, might be ineffective to control influenza. Vaccination of children, with the aim of reducing influenza transmission might be effective in African settings given the young population and high influenza burden. FUNDING: US Centers for Disease Control and Prevention.


Assuntos
Infecções Assintomáticas/epidemiologia , Influenza Humana/epidemiologia , Influenza Humana/transmissão , Saúde da População Rural/estatística & dados numéricos , Saúde da População Urbana/estatística & dados numéricos , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Estações do Ano , África do Sul/epidemiologia , Adulto Jovem
7.
Clin Infect Dis ; 73(3): e745-e753, 2021 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-33530100

RESUMO

BACKGROUND: Policy recommendations on pertussis vaccination need to be guided by data, which are limited from low- and middle-income countries. We aimed to describe the epidemiology of pertussis in South Africa, a country with high human immunodeficiency virus (HIV) prevalence and routine pertussis vaccination for 6 decades including the acellular vaccine since 2009. METHODS: Hospitalized patients of all ages were enrolled at 5 sentinel sites as part of a pneumonia surveillance program from January 2013 through December 2018. Nasopharyngeal specimens and induced sputum were tested by polymerase chain reaction (PCR) for Bordetella pertussis. In addition, demographic and clinical information were collected. Incidence rates were calculated for 2013-2016, and multivariable logistic regression performed to identify factors associated with pertussis. RESULTS: Over the 6-year period 19 429 individuals were enrolled, of which 239 (1.2%) tested positive for B. pertussis. Detection rate was highest in infants aged <6 months (2.8%, 155/5524). Mean annual incidence was 17 cases per 100 000 population, with the highest incidence in children <1 year of age (228 per 100 000). Age-adjusted incidence was 65.9 per 100 000 in HIV-infected individuals compared to 8.5 per 100 000 in HIV-uninfected individuals (risk ratio 30.4, 95% confidence interval: 23.0-40.2). Ten individuals (4.2%) with pertussis died; of which 7 were infants aged <6 months and 3 were immunocompromised adults. CONCLUSIONS: Pertussis continues to be a significant cause of illness and hospitalization in South Africa, despite routine vaccination. The highest burden of disease and death occurred in infants; however, HIV-infected adults were also identified as an important group at risk of B. pertussis infection.


Assuntos
Coqueluche , Adulto , Bordetella pertussis , Criança , Humanos , Incidência , Lactente , Vacina contra Coqueluche , África do Sul/epidemiologia , Coqueluche/epidemiologia
8.
Influenza Other Respir Viruses ; 15(4): 446-456, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33452708

RESUMO

BACKGROUND: There are conflicting data concerning the impact of antenatal influenza vaccination on birth outcomes including low birthweight (LBW), preterm birth, small for gestational age (SGA), and stillbirth. METHODS: We conducted a retrospective observational cohort study of infants born to women residing in Mitchells Plain, Cape Town. Infants were born at 4 health facilities during May 28 - December 31, 2015 and April 15 - December 31, 2016. We performed crude and multivariable logistic regression, propensity score (PS) matching logistic regression, and inverse probability of treatment weighted (IPTW) regression to assess vaccine effectiveness (VE) against LBW, preterm birth, SGA, and stillbirth adjusting for measured confounders. RESULTS: Maternal vaccination status, antenatal history, and ≥1 birth outcome(s) were available for 4084/5333 (76.6%) pregnancies, 2109 (51.6%) vaccinated, and 1975 (48.4%) unvaccinated. The proportion LBW was lower in vaccinated (6.9%) vs. unvaccinated (12.5%) in multivariable [VE 0.27 (95% CI 0.07-0.42)], PS [VE 0.30 (95% CI 0.09-0.51)], and IPTW [VE 0.24 (95% CI 0.04-0.45)]. Preterm birth was less frequent in vaccinated (8.6%) than unvaccinated (16.4%) in multivariable [VE 0.26 (0.09-0.40)], PS [VE 0.25 (95% CI 0.09-0.41)], and IPTW [VE 0.34 (95% CI 0.18-0.51)]. The proportion SGA was lower in vaccinated (6.0%) than unvaccinated (8.8%) but not in adjusted models. There were few stillbirths in our study population, 30/4084 (0.7%). CONCLUSIONS: Using multiple analytic approaches, we found that influenza vaccination was associated with lower prevalence of LBW (24-30%) and preterm birth (25-34%) in Cape Town during 2015-2016.


Assuntos
Vacinas contra Influenza , Influenza Humana , Nascimento Prematuro , Feminino , Humanos , Lactente , Recém-Nascido , Influenza Humana/epidemiologia , Influenza Humana/prevenção & controle , Gravidez , Nascimento Prematuro/epidemiologia , Nascimento Prematuro/prevenção & controle , Estudos Retrospectivos , África do Sul/epidemiologia , Vacinação
9.
Vaccine ; 38(45): 7007-7014, 2020 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-32980198

RESUMO

BACKGROUND: Data on influenza economic burden in risk groups for severe influenza are important to guide targeted influenza immunization, especially in resource-limited settings. However, this information is limited in low- and middle-income countries. METHODS: We estimated the cost (from a health system and societal perspective) and years of life lost (YLL) for influenza-associated illness in South Africa during 2013-2015 among (i) children aged 6-59 months, (ii) individuals aged 5-64 years with HIV, pulmonary tuberculosis (PTB) and selected underlying medical conditions (UMC), separately, (iii) pregnant women and (iv) individuals aged ≥65 years, using publicly available data and data collected through laboratory-confirmed influenza surveillance and costing studies. All costs were expressed in 2015 prices using the South Africa all-items Consumer Price Index. RESULTS: During 2013-2015, the mean annual cost of influenza-associated illness among the selected risk groups accounted for 52.1% ($140.9/$270.5 million) of the total influenza-associated illness cost (for the entire population of South Africa), 45.2% ($52.2/$115.5 million) of non-medically attended illness costs, 43.3% ($46.7/$107.9 million) of medically-attended mild illness costs and 89.3% ($42.0/$47.1 million) of medically-attended severe illness costs. The YLL among the selected risk groups accounted for 86.0% (262,069 /304,867 years) of the total YLL due to influenza-associated death. CONCLUSION: In South Africa, individuals in risk groups for severe influenza accounted for approximately half of the total influenza-associated illness cost but most of the cost of influenza-associated medically attended severe illness and YLL. This study provides the foundation for future studies on the cost-effectiveness of influenza immunization among risk groups.


Assuntos
Efeitos Psicossociais da Doença , Influenza Humana , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Análise Custo-Benefício , Feminino , Humanos , Influenza Humana/epidemiologia , Influenza Humana/prevenção & controle , Pessoa de Meia-Idade , Gravidez , África do Sul/epidemiologia , Vacinação , Adulto Jovem
10.
Vaccine ; 38(27): 4288-4297, 2020 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-32389494

RESUMO

BACKGROUND: Data on influenza burden in risk groups for severe influenza are important to guide targeted influenza immunization, especially in resource limited settings. However, this information is limited overall and in particular in low- and middle-income countries. We sought to assess the mean annual national burden of medically and non-medically attended influenza-associated mild, severe-non-fatal and fatal illness among potential target groups for influenza immunization in South Africa during 2013-2015. METHODS: We used published mean national annual estimates of mild, severe-non-fatal, and fatal influenza-associated illness in South Africa during 2013-2015 and estimated the number of such illnesses occurring among the following risk groups: (i) children aged 6-59 months; (ii) individuals aged 5-64 years with HIV, and/or pulmonary tuberculosis (PTB), and/or selected underlying medical conditions (UMC); (iii) pregnant women; and (iv) individuals aged ≥65 years. We also estimated the number of individuals among the same risk groups in the population. RESULTS: During 2013-2015, individuals in the selected risk groups accounted for 45.3% (24,569,328/54,086,144) of the population and 43.5% (4,614,763/10,598,138), 86.8% (111,245/128,173) and 94.5% (10,903/11,536) of the mean annual estimated number of influenza-associated mild, severe-non-fatal and fatal illness episodes, respectively. The rates of influenza-associated illness were highest in children aged 6-59 months (23,983 per 100,000 population) for mild illness, in pregnant women (930 per 100,000 population) for severe-non-fatal illness and in individuals aged ≥65 years (138 per 100,000 population) for fatal illness. CONCLUSION: Influenza immunization of the selected risk groups has the potential to prevent a substantial number of influenza-associated severe illness. Nonetheless, because of the high number of individuals at risk, South Africa, due to financial resources constrains, may need to further prioritize interventions among risk populations. Cost-burden and cost-effectiveness estimates may assist with further prioritization.


Assuntos
Influenza Humana , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Efeitos Psicossociais da Doença , Análise Custo-Benefício , Feminino , Humanos , Lactente , Influenza Humana/epidemiologia , Influenza Humana/prevenção & controle , Pessoa de Meia-Idade , Gravidez , África do Sul/epidemiologia , Vacinação , Adulto Jovem
11.
Vaccine ; 37(46): 6874-6884, 2019 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-31575494

RESUMO

BACKGROUND: Pregnant women and infants are at increased risk of severe disease from influenza. Antenatal influenza vaccination is safe and can reduce the risk of illness for women and their infants. We evaluated for South Africa the health effects of antenatal influenza vaccination among pregnant women and their infants aged <6 months old and assessed its cost-effectiveness. METHODS: We constructed a decision tree model to simulate the population of pregnant women and infants aged <6 months in South Africa using TreeAge Pro Suite 2015. The model evaluated the change in societal costs and outcomes associated with a vaccination campaign that prioritized HIV-infected over HIV-uninfected pregnant women compared with no vaccination. We also examined the impacts of a campaign without prioritization. Upper and lower 90% uncertainty intervals (90% UI) were generated using probabilistic sensitivity analysis on 10000 Monte Carlo simulations. The cost-effectiveness threshold was set to the 2015 per capita gross domestic product of South Africa, US$5724. RESULTS: Antenatal vaccination with prioritization averted 9070 (90% UI: 7407-11217) total cases of influenza among pregnant women and infants, including 411 (90% UI: 305-546) hospitalizations and 30 (90% UI: 22-40) deaths. This corresponds to an averted fraction of 13.5% (90% UI: 9.0-20.5%). Vaccinating without prioritization averted 7801 (90% UI: 6465-9527) cases of influenza, including 335 (90% UI: 254-440) hospitalizations and 24 (90% UI: 18-31) deaths. This corresponds to an averted fraction of 11.6% (90% UI: 7.8-17.4%). Vaccinating the cohort of pregnant women with prioritization had societal cost of $4689 (90% UI: $3128-$7294) per Quality Adjusted Life Year (QALY) gained while vaccinating without prioritization had a cost of $5924 (90% UI: $3992-$9056) per QALY. CONCLUSIONS: Antenatal influenza vaccination campaigns in South Africa would reduce the impact of influenza and could be cost-effective.


Assuntos
Influenza Humana/prevenção & controle , Análise Custo-Benefício , Feminino , Infecções por HIV/imunologia , Humanos , Recém-Nascido , Influenza Humana/epidemiologia , Influenza Humana/imunologia , Masculino , Método de Monte Carlo , Gravidez , África do Sul/epidemiologia , Vacinação/estatística & dados numéricos
12.
Influenza Other Respir Viruses ; 13(5): 484-495, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31187609

RESUMO

BACKGROUND: Economic burden estimates are essential to guide policy-making for influenza vaccination, especially in resource-limited settings. METHODS: We estimated the cost, absenteeism, and years of life lost (YLL) of medically and non-medically attended influenza-associated mild and severe respiratory, circulatory and non-respiratory/non-circulatory illness in South Africa during 2013-2015 using a modified version of the World Health Organization (WHO) worksheet based tool for estimating the economic burden of seasonal influenza. Additionally, we restricted the analysis to influenza-associated severe acute respiratory illness (SARI) and influenza-like illness (ILI; subsets of all-respiratory illnesses) as suggested in the WHO manual. RESULTS: The estimated mean annual cost of influenza-associated illness was $270.5 million, of which $111.3 million (41%) were government-incurred costs, 40.7 million (15%) were out-of-pocket expenses, and $118.4 million (44%) were indirect costs. The cost of influenza-associated medically attended mild illness ($107.9 million) was 2.3 times higher than that of severe illness ($47.1 million). Influenza-associated respiratory illness costs ($251.4 million) accounted for 93% of the total cost. Estimated absenteeism and YLL were 13.2 million days and 304 867 years, respectively. Among patients with influenza-associated WHO-defined ILI or SARI, the costs ($95.3 million), absenteeism (4.5 million days), and YLL (65 697) were 35%, 34%, and 21% of the total economic and health burden of influenza. CONCLUSION: The economic burden of influenza-associated illness was substantial from both a government and a societal perspective. Models that limit estimates to those obtained from patients with WHO-defined ILI or SARI substantially underestimated the total economic and health burden of influenza-associated illness.


Assuntos
Absenteísmo , Efeitos Psicossociais da Doença , Hospitalização/economia , Influenza Humana/economia , Expectativa de Vida , Hospitalização/estatística & dados numéricos , Humanos , Vacinas contra Influenza/administração & dosagem , Influenza Humana/complicações , Influenza Humana/epidemiologia , Estações do Ano , Vigilância de Evento Sentinela , África do Sul/epidemiologia , Vacinação/legislação & jurisprudência
13.
Clin Infect Dis ; 69(12): 2208-2211, 2019 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-30963178

RESUMO

From 2011 through 2016, we conducted surveillance for severe respiratory illness in infants. Human immunodeficiency virus exposure significantly increased the risk of respiratory syncytial virus (RSV)-associated hospitalization in infants aged <5 months. More than 60% of RSV-associated hospitalizations occurred in the first 4 months of life and may be preventable through maternal vaccination or birth-dose monoclonal antibody.


Assuntos
Coinfecção , Infecções por HIV/epidemiologia , Infecções por Vírus Respiratório Sincicial/epidemiologia , Infecções por Vírus Respiratório Sincicial/virologia , Vírus Sincicial Respiratório Humano , Feminino , Infecções por HIV/virologia , História do Século XXI , Hospitalização , Humanos , Lactente , Recém-Nascido , Masculino , Programas de Rastreamento , Infecções por Vírus Respiratório Sincicial/diagnóstico , Infecções por Vírus Respiratório Sincicial/história , Índice de Gravidade de Doença , África do Sul/epidemiologia
14.
Clin Infect Dis ; 68(5): 773-780, 2019 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-29961814

RESUMO

BACKGROUND: Data describing influenza- or respiratory syncytial virus (RSV)-associated hospitalized illness in children aged <5 years in Africa are limited. METHODS: During 2011-2016, we conducted surveillance for severe respiratory illness (SRI) in children aged <5 years in 3 South African hospitals. Nasopharyngeal aspirates were tested for influenza and RSV using real-time reverse transcription polymerase chain reaction. We estimated rates of influenza- and RSV-associated hospitalized SRI by human immunodeficiency virus (HIV) status and compared children who tested positive for influenza vs RSV using multivariable penalized logistic regression. RESULTS: Among 3650 hospitalized children, 203 (5.6%) tested positive for influenza viruses, 874 (23.9%) for RSV, and 19 (0.5%) for both. The median age of children hospitalized with influenza was 13.9 months vs 4.4 months for RSV (P < .01). Annual influenza-associated hospitalization rates per 100000 were highest among infants aged 6-11 months (545; 95% confidence interval [CI], 409-703), while RSV-associated hospitalization rates were highest in infants aged 0-2 months (6593; 95% CI, 5947-7217). HIV exposure was associated with increased incidence of influenza- and RSV-associated hospitalization in infants aged 0-5 months, with relative risk (RR) 2.2 (95% CI, 1.4-3.4) and 1.4 (95% CI, 1.3-1.6), respectively. HIV infection was associated with increased incidence of influenza- and RSV-associated hospitalization in all age groups; RR 2.7 (95% CI, 2.0-3.5) and 3.8 (95% CI, 3.1-4.8), respectively. CONCLUSIONS: Influenza- and RSV-associated hospitalizations are common among South African infants. HIV infection and HIV exposure in infants increase risk of influenza- and RSV-associated hospitalization.


Assuntos
Infecções por HIV/complicações , Influenza Humana/complicações , Infecções por Vírus Respiratório Sincicial/complicações , Pré-Escolar , Coinfecção , Infecções por HIV/epidemiologia , Hospitalização , Humanos , Lactente , Influenza Humana/epidemiologia , Infecções por Vírus Respiratório Sincicial/epidemiologia , Fatores de Risco , Estações do Ano , África do Sul/epidemiologia , Fatores de Tempo
15.
Vaccine ; 37(1): 25-33, 2019 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-30471956

RESUMO

BACKGROUND: Due to competing health priorities, low- and middle-income countries (LMIC) may need to prioritize between different influenza vaccine risk groups. Risk group prioritization may differ in LMIC based upon programmatic feasibility, country-specific prevalence of risk conditions and influenza-associated morbidity and mortality. METHODS: In South Africa, we collected local disease burden data (both published and unpublished) and published vaccine efficacy data in risk groups and healthy adults. We used these data to aid policy makers with risk group prioritization for influenza vaccination. We used the following formula to assess potential vaccine averted disease in each risk group: rate of influenza-associated hospitalization (or death) per 100,000 population * influenza vaccine efficacy (VE). We further estimated the cost per hospital day averted and the cost per year of life saved by influenza vaccination. RESULTS: Pregnant women, HIV-infected adults, and adults and children with tuberculosis disease had among the highest estimates of hospitalizations averted per 100,000 vaccinated and adults aged 65 years and older had the highest estimated deaths averted per 100,000 vaccinated. However, when assessing both the cost per hospital day averted (range: USD148-1,344) and the cost per year of life saved (range: USD112-1,230); adults and children with TB disease, HIV-infected adults and pregnant women had the lowest cost per outcome averted. DISCUSSION: An assessment of the potential disease outcomes averted and associated costs may aid policymakers in risk group prioritization for influenza vaccination.


Assuntos
Prioridades em Saúde , Recursos em Saúde , Vacinas contra Influenza/economia , Influenza Humana/prevenção & controle , Vacinação/economia , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Criança , Pré-Escolar , Efeitos Psicossociais da Doença , Análise Custo-Benefício , Feminino , Infecções por HIV/epidemiologia , Hospitalização/economia , Hospitalização/estatística & dados numéricos , Humanos , Lactente , Vacinas contra Influenza/uso terapêutico , Influenza Humana/mortalidade , Masculino , Pessoa de Meia-Idade , Gravidez , Fatores de Risco , África do Sul , Tuberculose/epidemiologia , Adulto Jovem
16.
Clin Infect Dis ; 69(6): 1036-1048, 2019 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-30508065

RESUMO

BACKGROUND: Burden estimates of medically and nonmedically attended influenza-associated illness across syndromes and levels of severity are lacking. METHODS: We estimated the national burden of medically and nonmedically attended influenza-associated illness among individuals with different clinical presentations (all-respiratory, all-circulatory, and nonrespiratory/noncirculatory) and levels of severity (mild, fatal, and severe, nonfatal) using a combination of case-based (from laboratory-confirmed influenza surveillance) and ecological studies, as well as data from healthcare utilization surveys in South Africa during 2013-2015. In addition, we compared estimates of medically attended influenza-associated respiratory illness, obtained from case-based and ecological studies. Rates were reported per 100 000 individuals in the population. RESULTS: The estimated mean annual number of influenza-associated illness episodes was 10 737 847 (19.8% of 54 096 705 inhabitants). Of these episodes, 10 598 138 (98.7%) were mild, 128 173 (1.2%) were severe, nonfatal, and 11 536 (0.1%) were fatal. There were 2 718 140 (25.6%) mild, 56 226 (43.9%) severe, nonfatal, and 4945 (42.8%) medically attended should be after fatal episodes. Influenza-associated respiratory illness accounted for 99.2% (10 576 146) of any mild, 65.5% (83 941) of any severe, nonfatal, and 33.7% (3893) of any fatal illnesses. Ecological and case-based estimates of medically attended, influenza-associated, respiratory mild (rates: ecological, 1778.8, vs case-based, 1703.3; difference, 4.4%), severe, nonfatal (rates: ecological, 88.6, vs case-based, 75.3; difference, 15.0%), and fatal (rates: ecological, 3.8, vs case-based, 3.5; difference, 8.4%) illnesses were similar. CONCLUSIONS: There was a substantial burden of influenza-associated symptomatic illness, including severe, nonfatal and fatal illnesses, and a large proportion was nonmedically attended. Estimates, including only influenza-associated respiratory illness, substantially underestimated influenza-associated, severe, nonfatal and fatal illnesses. Ecological and case-based estimates were found to be similar for the compared categories.


Assuntos
Variação Biológica da População , Efeitos Psicossociais da Doença , Influenza Humana/diagnóstico , Influenza Humana/epidemiologia , Padrões de Prática Médica , Comorbidade , Análise Custo-Benefício , Gerenciamento Clínico , Feminino , Humanos , Influenza Humana/mortalidade , Masculino , Modelos Teóricos , Prognóstico , Vigilância em Saúde Pública , Doenças Respiratórias/epidemiologia , Doenças Respiratórias/etiologia , África do Sul/epidemiologia , Avaliação de Sintomas
17.
BMC Infect Dis ; 18(1): 344, 2018 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-30045687

RESUMO

BACKGROUND: Asking people how they would seek healthcare in a hypothetical situation can be an efficient way to estimate healthcare utilization, but it is unclear how intended healthcare use corresponds to actual healthcare use. METHODS: We performed a cross-sectional survey between August and September 2012 among households in Soweto and Klerksdorp, South Africa, to compare healthcare seeking behaviors intended for hypothetical common infectious syndromes (pneumonia, influenza-like illness [ILI], chronic respiratory illness, meningitis in persons of any age, and diarrhea in a child < 5 years old) with the self-reported healthcare use among patients with those syndromes. RESULTS: For most syndromes, the proportion of respondents who intended to seek healthcare at any facility or provider (99-100%) in a hypothetical scenario exceeded the proportion that did seek care (78-100%). More people intended to seek care for a child < 5 years old with diarrhea (186/188 [99%]) than actually did seek care (32/41 [78%], P < 0.01). Although most people faced with hypothetical scenarios intended to seek care with licensed medical providers such as hospitals and clinics (97-100%), patients who were ill reported lower use of licensed medical providers (55-95%). CONCLUSIONS: People overestimated their intended healthcare utilization, especially with licensed medical providers, compared with reported healthcare utilization among patients with these illnesses. Studies that measure intended healthcare utilization should consider that actual use of healthcare facilities may be lower than intended use.


Assuntos
Doenças Transmissíveis , Diarreia , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Adulto , Pré-Escolar , Doenças Transmissíveis/epidemiologia , Doenças Transmissíveis/terapia , Estudos Transversais , Diarreia/epidemiologia , Diarreia/terapia , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , África do Sul/epidemiologia
18.
Influenza Other Respir Viruses ; 12(3): 360-373, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29210203

RESUMO

BACKGROUND: The attributable fraction of influenza virus detection to illness (INF-AF) and the duration of symptoms as a surveillance inclusion criterion could potentially have substantial effects on influenza disease burden estimates. METHODS: We estimated rates of influenza-associated influenza-like illness (ILI) and severe acute (SARI-10) or chronic (SCRI-10) respiratory illness (using a symptom duration cutoff of ≤10 days) among HIV-infected and HIV-uninfected patients attending 3 hospitals and 2 affiliated clinics in South Africa during 2013-2015. We calculated the unadjusted and INF-AF-adjusted rates and relative risk (RR) due to HIV infection. Rates were expressed per 100 000 population. RESULTS: The estimated mean annual unadjusted rates of influenza-associated illness were 1467.7, 50.3, and 27.4 among patients with ILI, SARI-10, and SCRI-10, respectively. After adjusting for the INF-AF, the percent reduction in the estimated rates was 8.9% (rate: 1336.9), 11.0% (rate: 44.8), and 16.3% (rate: 22.9) among patients with ILI, SARI-10, and SCRI-10, respectively. HIV-infected compared to HIV-uninfected individuals experienced a 2.3 (95% CI: 2.2-2.4)-, 9.7 (95% CI: 8.0-11.8)-, and 10.0 (95% CI: 7.9-12.7)-fold increased risk of influenza-associated illness among patients with ILI, SARI-10, and SCRI-10, respectively. Overall 34% of the estimated influenza-associated hospitalizations had symptom duration of >10 days; 8% and 44% among individuals aged <5 and ≥5 years, respectively. CONCLUSION: The marginal differences between unadjusted and INF-AF-adjusted rates are unlikely to affect policies on prioritization of interventions. HIV-infected individuals experienced an increased risk of influenza-associated illness and may benefit more from annual influenza immunization. The use of a symptom duration cutoff of ≤10 days may underestimate influenza-associated disease burden, especially in older individuals.


Assuntos
Efeitos Psicossociais da Doença , Monitoramento Epidemiológico , Infecções por HIV/epidemiologia , Infecções Respiratórias/epidemiologia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Infecções por HIV/complicações , Infecções por HIV/virologia , Humanos , Influenza Humana/epidemiologia , Influenza Humana/virologia , Masculino , Pessoa de Meia-Idade , Nasofaringe/virologia , Orthomyxoviridae/isolamento & purificação , Prevalência , Estudos Prospectivos , Infecções Respiratórias/virologia , África do Sul/epidemiologia , Adulto Jovem
19.
PLoS One ; 12(12): e0189623, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29283997

RESUMO

BACKGROUND: Recent influenza surveillance data from Africa suggest an important burden of influenza-associated morbidity and mortality. In tropical countries where influenza virus transmission may not be confined to a single season alternative strategies for vaccine distribution via antenatal care (ANC) or semiannual campaigns should be considered. METHODS: Using data on monthly influenza disease burden in women of child-bearing age and infants aged 0-5 months in Kenya from 2010-2014, we estimated the number of outcomes (illnesses, medical visits, hospitalizations, and deaths) that occurred and that may have been averted through influenza vaccination of pregnant women using: 1) a year-round immunization strategy through ANC, 2) annual vaccination campaigns, and 3) semiannual vaccination campaigns. RESULTS: During 2010-2014, influenza resulted in an estimated 279,047 illnesses, 36,276 medical visits, 1612 hospitalizations and 243 deaths in pregnant women and 157,053 illnesses, 65,177 medical visits, 4197 hospitalizations, and 755 deaths in infants aged 0-5 months in Kenya. Depending on the mode of distribution and the vaccine coverage achieved, 12.8-31.4% of influenza-associated disease in pregnant women and 11.6-22.1% in infants aged 0-5 months might have been prevented through maternal influenza immunization. In this model, point estimates for influenza-associated disease averted through maternal vaccination delivered year-round in ANC or semiannually in campaigns were higher than vaccination delivered in a single annual campaign, but confidence intervals overlapped. CONCLUSIONS: Vaccinating pregnant women against influenza can reduce the burden of influenza-associated illness, hospitalization and death in both pregnant women and their young infants. Alternative immunization strategies may avert more influenza-associated disease in countries where influenza virus transmission occurs throughout the year.


Assuntos
Vacinas contra Influenza/administração & dosagem , Influenza Humana/epidemiologia , Complicações Infecciosas na Gravidez/prevenção & controle , Adolescente , Adulto , Feminino , Humanos , Lactente , Mortalidade Infantil , Recém-Nascido , Influenza Humana/mortalidade , Influenza Humana/prevenção & controle , Quênia/epidemiologia , Pessoa de Meia-Idade , Gravidez , Complicações Infecciosas na Gravidez/mortalidade , Estações do Ano , Adulto Jovem
20.
Emerg Infect Dis ; 23(7): 1124-1132, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28628462

RESUMO

The attributable fraction (AF) of influenza virus detection to illness has not been described for patients in different age groups or with different HIV infection statuses. We compared the age group-specific prevalence of influenza virus infection among patients with influenza-like illness (ILI) or severe acute or chronic respiratory illness (SARI and SCRI, respectively) with that among controls, stratified by HIV serostatus. The overall AF for influenza virus detection to illness was 92.6% for ILI, 87.4% for SARI, and 86.2% for SCRI. Among HIV-uninfected patients, the AF for all syndromes was highest among persons <1 and >65 years of age and lowest among persons 25-44 years of age; this trend was not observed among HIV-infected patients. Overall, influenza viruses when detected in patients with ILI, SARI, or SCRI are likely attributable to illness. This finding is particularly likely among children and the elderly irrespective of HIV serostatus and among HIV-infected persons irrespective of age.


Assuntos
Coinfecção/epidemiologia , Infecções por HIV/epidemiologia , Infecções por HIV/virologia , Orthomyxoviridae , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/virologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , História do Século XXI , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Orthomyxoviridae/classificação , Orthomyxoviridae/genética , Vigilância da População , Prevalência , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/história , Índice de Gravidade de Doença , África do Sul/epidemiologia , Adulto Jovem
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