1
|
Jefferson T, Dooley L, Ferroni E, Al-Ansary LA, van Driel ML, Bawazeer GA, Jones MA, Hoffmann TC, Clark J, Beller EM, Glasziou PP, Conly JM. Physical interventions to interrupt or reduce the spread of respiratory viruses. Cochrane Database Syst Rev 2023; 1:CD006207. [PMID: 36715243 PMCID: PMC9885521 DOI: 10.1002/14651858.cd006207.pub6] [Citation(s) in RCA: 47] [Impact Index Per Article: 47.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND Viral epidemics or pandemics of acute respiratory infections (ARIs) pose a global threat. Examples are influenza (H1N1) caused by the H1N1pdm09 virus in 2009, severe acute respiratory syndrome (SARS) in 2003, and coronavirus disease 2019 (COVID-19) caused by SARS-CoV-2 in 2019. Antiviral drugs and vaccines may be insufficient to prevent their spread. This is an update of a Cochrane Review last published in 2020. We include results from studies from the current COVID-19 pandemic. OBJECTIVES To assess the effectiveness of physical interventions to interrupt or reduce the spread of acute respiratory viruses. SEARCH METHODS We searched CENTRAL, PubMed, Embase, CINAHL, and two trials registers in October 2022, with backwards and forwards citation analysis on the new studies. SELECTION CRITERIA We included randomised controlled trials (RCTs) and cluster-RCTs investigating physical interventions (screening at entry ports, isolation, quarantine, physical distancing, personal protection, hand hygiene, face masks, glasses, and gargling) to prevent respiratory virus transmission. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methodological procedures. MAIN RESULTS We included 11 new RCTs and cluster-RCTs (610,872 participants) in this update, bringing the total number of RCTs to 78. Six of the new trials were conducted during the COVID-19 pandemic; two from Mexico, and one each from Denmark, Bangladesh, England, and Norway. We identified four ongoing studies, of which one is completed, but unreported, evaluating masks concurrent with the COVID-19 pandemic. Many studies were conducted during non-epidemic influenza periods. Several were conducted during the 2009 H1N1 influenza pandemic, and others in epidemic influenza seasons up to 2016. Therefore, many studies were conducted in the context of lower respiratory viral circulation and transmission compared to COVID-19. The included studies were conducted in heterogeneous settings, ranging from suburban schools to hospital wards in high-income countries; crowded inner city settings in low-income countries; and an immigrant neighbourhood in a high-income country. Adherence with interventions was low in many studies. The risk of bias for the RCTs and cluster-RCTs was mostly high or unclear. Medical/surgical masks compared to no masks We included 12 trials (10 cluster-RCTs) comparing medical/surgical masks versus no masks to prevent the spread of viral respiratory illness (two trials with healthcare workers and 10 in the community). Wearing masks in the community probably makes little or no difference to the outcome of influenza-like illness (ILI)/COVID-19 like illness compared to not wearing masks (risk ratio (RR) 0.95, 95% confidence interval (CI) 0.84 to 1.09; 9 trials, 276,917 participants; moderate-certainty evidence. Wearing masks in the community probably makes little or no difference to the outcome of laboratory-confirmed influenza/SARS-CoV-2 compared to not wearing masks (RR 1.01, 95% CI 0.72 to 1.42; 6 trials, 13,919 participants; moderate-certainty evidence). Harms were rarely measured and poorly reported (very low-certainty evidence). N95/P2 respirators compared to medical/surgical masks We pooled trials comparing N95/P2 respirators with medical/surgical masks (four in healthcare settings and one in a household setting). We are very uncertain on the effects of N95/P2 respirators compared with medical/surgical masks on the outcome of clinical respiratory illness (RR 0.70, 95% CI 0.45 to 1.10; 3 trials, 7779 participants; very low-certainty evidence). N95/P2 respirators compared with medical/surgical masks may be effective for ILI (RR 0.82, 95% CI 0.66 to 1.03; 5 trials, 8407 participants; low-certainty evidence). Evidence is limited by imprecision and heterogeneity for these subjective outcomes. The use of a N95/P2 respirators compared to medical/surgical masks probably makes little or no difference for the objective and more precise outcome of laboratory-confirmed influenza infection (RR 1.10, 95% CI 0.90 to 1.34; 5 trials, 8407 participants; moderate-certainty evidence). Restricting pooling to healthcare workers made no difference to the overall findings. Harms were poorly measured and reported, but discomfort wearing medical/surgical masks or N95/P2 respirators was mentioned in several studies (very low-certainty evidence). One previously reported ongoing RCT has now been published and observed that medical/surgical masks were non-inferior to N95 respirators in a large study of 1009 healthcare workers in four countries providing direct care to COVID-19 patients. Hand hygiene compared to control Nineteen trials compared hand hygiene interventions with controls with sufficient data to include in meta-analyses. Settings included schools, childcare centres and homes. Comparing hand hygiene interventions with controls (i.e. no intervention), there was a 14% relative reduction in the number of people with ARIs in the hand hygiene group (RR 0.86, 95% CI 0.81 to 0.90; 9 trials, 52,105 participants; moderate-certainty evidence), suggesting a probable benefit. In absolute terms this benefit would result in a reduction from 380 events per 1000 people to 327 per 1000 people (95% CI 308 to 342). When considering the more strictly defined outcomes of ILI and laboratory-confirmed influenza, the estimates of effect for ILI (RR 0.94, 95% CI 0.81 to 1.09; 11 trials, 34,503 participants; low-certainty evidence), and laboratory-confirmed influenza (RR 0.91, 95% CI 0.63 to 1.30; 8 trials, 8332 participants; low-certainty evidence), suggest the intervention made little or no difference. We pooled 19 trials (71, 210 participants) for the composite outcome of ARI or ILI or influenza, with each study only contributing once and the most comprehensive outcome reported. Pooled data showed that hand hygiene may be beneficial with an 11% relative reduction of respiratory illness (RR 0.89, 95% CI 0.83 to 0.94; low-certainty evidence), but with high heterogeneity. In absolute terms this benefit would result in a reduction from 200 events per 1000 people to 178 per 1000 people (95% CI 166 to 188). Few trials measured and reported harms (very low-certainty evidence). We found no RCTs on gowns and gloves, face shields, or screening at entry ports. AUTHORS' CONCLUSIONS The high risk of bias in the trials, variation in outcome measurement, and relatively low adherence with the interventions during the studies hampers drawing firm conclusions. There were additional RCTs during the pandemic related to physical interventions but a relative paucity given the importance of the question of masking and its relative effectiveness and the concomitant measures of mask adherence which would be highly relevant to the measurement of effectiveness, especially in the elderly and in young children. There is uncertainty about the effects of face masks. The low to moderate certainty of evidence means our confidence in the effect estimate is limited, and that the true effect may be different from the observed estimate of the effect. The pooled results of RCTs did not show a clear reduction in respiratory viral infection with the use of medical/surgical masks. There were no clear differences between the use of medical/surgical masks compared with N95/P2 respirators in healthcare workers when used in routine care to reduce respiratory viral infection. Hand hygiene is likely to modestly reduce the burden of respiratory illness, and although this effect was also present when ILI and laboratory-confirmed influenza were analysed separately, it was not found to be a significant difference for the latter two outcomes. Harms associated with physical interventions were under-investigated. There is a need for large, well-designed RCTs addressing the effectiveness of many of these interventions in multiple settings and populations, as well as the impact of adherence on effectiveness, especially in those most at risk of ARIs.
Collapse
Affiliation(s)
- Tom Jefferson
- Department for Continuing Education, University of Oxford, Oxford OX1 2JA, UK
| | - Liz Dooley
- Institute for Evidence-Based Healthcare, Bond University, Gold Coast, Australia
| | - Eliana Ferroni
- Epidemiological System of the Veneto Region, Regional Center for Epidemiology, Veneto Region, Padova, Italy
| | - Lubna A Al-Ansary
- Department of Family and Community Medicine, King Saud University, Riyadh, Saudi Arabia
| | - Mieke L van Driel
- General Practice Clinical Unit, Faculty of Medicine, The University of Queensland, Brisbane, Australia
- Department of Public Health and Primary Care, Ghent University, Ghent, Belgium
| | - Ghada A Bawazeer
- Department of Clinical Pharmacy, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia
| | - Mark A Jones
- Institute for Evidence-Based Healthcare, Bond University, Gold Coast, Australia
| | - Tammy C Hoffmann
- Institute for Evidence-Based Healthcare, Bond University, Gold Coast, Australia
| | - Justin Clark
- Institute for Evidence-Based Healthcare, Bond University, Gold Coast, Australia
| | - Elaine M Beller
- Institute for Evidence-Based Healthcare, Bond University, Gold Coast, Australia
| | - Paul P Glasziou
- Institute for Evidence-Based Healthcare, Bond University, Gold Coast, Australia
| | - John M Conly
- Cumming School of Medicine, University of Calgary, Room AGW5, SSB, Foothills Medical Centre, Calgary, Canada
- O'Brien Institute for Public Health and Synder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Canada
- Calgary Zone, Alberta Health Services, Calgary, Canada
| |
Collapse
|
2
|
Chu VT, Simon E, Lu X, Rockwell P, Abedi GR, Gardner C, Kujawski SA, Schneider E, Gentile M, Ramsey LA, Liu R, Jones S, Janik C, Siniscalchi A, Landry ML, Christopher J, Lindstrom S, Steiner S, Thomas D, Gerber SI, Biggs HM. Outbreak of Acute Respiratory Illness Associated with Human Adenovirus Type 4 at the U.S. Coast Guard Academy, 2019. J Infect Dis 2021; 225:55-64. [PMID: 34139752 DOI: 10.1093/infdis/jiab322] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Accepted: 06/16/2021] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Although a human adenovirus (HAdV) vaccine is available for military use, officers-in-training are not routinely vaccinated. We describe an HAdV-associated respiratory outbreak among unvaccinated cadets at the U.S. Coast Guard Academy and its impact on cadet training. METHODS We defined a case as a cadet with new onset cough or sore throat during August 1-October 4, 2019. We reviewed medical records and distributed a questionnaire to identify cases and to estimate impact on cadet training. We performed real-time PCR testing on patient and environmental samples and whole genome sequencing on a subset of positive patient samples. RESULTS Among the 1,072 cadets, 378 (35%) cases were identified by medical records (n=230) or additionally by the questionnaire (n=148). Of the 230 cases identified from medical records, 138 (60%) were male and 226 (98%) had no underlying conditions. From questionnaire responses, 113/228 (50%) cases reported duty restrictions. Of cases with respiratory specimens, 36/50 (72%) were HAdV positive; all 14 sequenced specimens were HAdV-4a1. Sixteen (89%) of 18 environmental specimens from the cadet dormitory were HAdV-positive. CONCLUSIONS The HAdV-4-associated outbreak infected a substantial number of cadets and significantly impacted cadet training. Routine vaccination could prevent HAdV respiratory outbreaks in this population.
Collapse
Affiliation(s)
- Victoria T Chu
- National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, USA.,Epidemic Intelligence Service, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Esan Simon
- United States Coast Guard Academy, New London, Connecticut, USA.,United States Public Health Service, Rockville, Maryland, USA
| | - Xiaoyan Lu
- National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | | | - Glen R Abedi
- National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Christopher Gardner
- United States Coast Guard Academy, New London, Connecticut, USA.,Yale-New Haven Hospital and Yale University, New Haven, Connecticut, USA
| | - Stephanie A Kujawski
- National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, USA.,Epidemic Intelligence Service, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Eileen Schneider
- National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Micah Gentile
- United States Coast Guard Academy, New London, Connecticut, USA
| | - Lee Ann Ramsey
- National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Robert Liu
- United States Coast Guard Academy, New London, Connecticut, USA
| | - Sydney Jones
- Epidemic Intelligence Service, Centers for Disease Control and Prevention, Atlanta, Georgia, USA.,Connecticut Department of Public Health, Hartford, Connecticut, USA
| | - Christopher Janik
- United States Coast Guard Academy, New London, Connecticut, USA.,United States Public Health Service, Rockville, Maryland, USA
| | - Alan Siniscalchi
- Connecticut Department of Public Health, Hartford, Connecticut, USA
| | - Marie L Landry
- Yale-New Haven Hospital and Yale University, New Haven, Connecticut, USA
| | | | - Stephen Lindstrom
- National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Shane Steiner
- United States Public Health Service, Rockville, Maryland, USA.,United States Coast Guard, Washington, D.C., USA
| | - Dana Thomas
- United States Public Health Service, Rockville, Maryland, USA.,United States Coast Guard, Washington, D.C., USA
| | - Susan I Gerber
- National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Holly M Biggs
- National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| |
Collapse
|
3
|
Impact of social distancing on the spread of common respiratory viruses during the coronavirus disease outbreak. PLoS One 2021; 16:e0252963. [PMID: 34125839 PMCID: PMC8202938 DOI: 10.1371/journal.pone.0252963] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Accepted: 05/25/2021] [Indexed: 12/21/2022] Open
Abstract
During the coronavirus disease (COVID-19) pandemic, social distancing was effective in controlling disease spread across South Korea. The impact of national social distancing on the spread of common respiratory virus infections has rarely been investigated. We evaluated the weekly proportion of negative respiratory virus polymerase chain reaction (PCR) test results and weekly positive rates of each respiratory virus during the social distancing period (10th-41st weeks of 2020) and the corresponding period in different years, utilizing the national respiratory virus surveillance dataset reported by the Korean Center for Disease Control and Prevention. The proportions of negative respiratory virus PCR test results increased up to 87.8% and 86.1% during level 3 and level 2 of the social distancing period, respectively. The higher the level of social distancing, the higher the proportion of negative respiratory virus PCR test results. During the social distancing period, the mean weekly positive rates for parainfluenza virus, influenza virus, human coronavirus, and human metapneumovirus were significantly lower than those during the same period in 2015-2019 (0.1% vs. 9.3%, P <0.001; 0.1% vs. 7.2%, P <0.001; 0.4% vs. 2.3%, P <0.001; and 0.2% vs. 5.3%, P <0.001, respectively). The mean positive rate for rhinovirus/enterovirus during level 3 social distancing was lower than that in the same period in 2015-2019 (8.5% vs. 19.0%, P <0.001), but the rate during level 1 social distancing was higher than that in the same period in 2015-2019 (38.3% vs. 19.4%, P <0.001). The national application of social distancing reduced the spread of common respiratory virus infections during the COVID-19 pandemic.
Collapse
|
4
|
Bielecki M, Züst R, Siegrist D, Meyerhofer D, Crameri GAG, Stanga ZG, Stettbacher A, Buehrer TW, Deuel JW. Social Distancing Alters the Clinical Course of COVID-19 in Young Adults: A Comparative Cohort Study. Clin Infect Dis 2021; 72:598-603. [PMID: 32594121 PMCID: PMC7337655 DOI: 10.1093/cid/ciaa889] [Citation(s) in RCA: 55] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Accepted: 06/23/2020] [Indexed: 01/19/2023] Open
Abstract
BACKGROUND Social distancing and stringent hygiene seem to be effective in reducing the number of transmitted virus particles, and therefore the infectivity, of coronavirus disease 2019 (COVID-19) and could alter the mode of transmission of the disease. However, it is not known if such practices can change the clinical course in infected individuals. METHODS We prospectively studied an outbreak of COVID-19 in Switzerland among a population of 508 predominantly male soldiers with a median age of 21 years. We followed the number of infections in 2 spatially separated cohorts with almost identical baseline characteristics with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) before and after implementation of stringent social distancing. RESULTS Of the 354 soldiers infected prior to the implementation of social distancing, 30% fell ill from COVID-19, while no soldier in a group of 154, in which infections appeared after implementation of social distancing, developed COVID-19 despite the detection of viral RNA in the nasal and virus-specific antibodies within this group. CONCLUSIONS Social distancing not only can slow the spread of SARS-CoV-2 in a cohort of young, healthy adults but it can also prevent the outbreak of COVID-19 while still inducing an immune response and colonizing nasal passages. Viral inoculum during infection or mode of transmission may be a key factor determining the clinical course of COVID-19.
Collapse
Affiliation(s)
- Michel Bielecki
- Swiss Armed Forces, Medical Services, Worblentalstrasse, Ittigen, Switzerland
- Swiss Armed Forces, Sanitary Medical School, Piazza d’armi, Airolo, Switzerland
- University of Zurich, Institute for Epidemiology, Biostatistics and Prevention Institute, Travel Clinic, Hirschengraben, Zürich, Switzerland
| | - Roland Züst
- Federal Office for Civil Protection FOCP, Spiez Laboratory, Austrasse, Spiez, Switzerland
| | - Denise Siegrist
- Federal Office for Civil Protection FOCP, Spiez Laboratory, Austrasse, Spiez, Switzerland
| | - Daniele Meyerhofer
- Swiss Armed Forces, Sanitary Medical School, Piazza d’armi, Airolo, Switzerland
| | | | - Zeno Giovanni Stanga
- Swiss Armed Forces, Medical Services, Worblentalstrasse, Ittigen, Switzerland
- Department of Diabetes, Endocrinology, Nutritional Medicine and Metabolism, Inselspital, Bern University Hospital, and University of Bern, Bern, Switzerland
| | - Andreas Stettbacher
- Swiss Armed Forces, Medical Services, Worblentalstrasse, Ittigen, Switzerland
| | | | - Jeremy Werner Deuel
- Swiss Armed Forces, Medical Services, Worblentalstrasse, Ittigen, Switzerland
- Swiss Armed Forces, Sanitary Medical School, Piazza d’armi, Airolo, Switzerland
- University of Cambridge, Department of Haematology and MRC - Wellcome Stem Cell Institute, Jeffrey Cheah Biomedical Centre, Puddicombe Way, Cambridge, United Kingdom
| |
Collapse
|
5
|
Kajon AE, Lamson DM, Bair CR, Lu X, Landry ML, Menegus M, Erdman DD, St George K. Adenovirus Type 4 Respiratory Infections among Civilian Adults, Northeastern United States, 2011-2015 1. Emerg Infect Dis 2019; 24:201-209. [PMID: 29350143 PMCID: PMC5782899 DOI: 10.3201/eid2402.171407] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Human adenovirus type 4 (HAdV-4) is most commonly isolated in military settings. We conducted detailed molecular characterization on 36 HAdV-4 isolates recovered from civilian adults with acute respiratory disease (ARD) in the northeastern United States during 2011–2015. Specimens came from college students, residents of long-term care facilities or nursing homes, a cancer patient, and young adults without co-morbidities. HAdV-4 genome types 4a1 and 4a2, the variants most frequently detected among US military recruits in basic training before the restoration of vaccination protocols, were isolated in most cases. Two novel a-like variants were recovered from students enrolled at a college in Tompkins County, New York, USA, and a prototype-like variant distinguishable from the vaccine strain was isolated from an 18-year-old woman visiting a physician’s office in Ulster County, New York, USA, with symptoms of influenza-like illness. Our data suggest that HAdV-4 might be an underestimated causative agent of ARD among civilian adults.
Collapse
|
6
|
Park JY, Kim BJ, Lee EJ, Park KS, Park HS, Jung SS, Kim JO. Clinical Features and Courses of Adenovirus Pneumonia in Healthy Young Adults during an Outbreak among Korean Military Personnel. PLoS One 2017; 12:e0170592. [PMID: 28114362 PMCID: PMC5256920 DOI: 10.1371/journal.pone.0170592] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Accepted: 01/06/2017] [Indexed: 11/19/2022] Open
Abstract
Background The number of pneumonia patients increased suddenly in Korean military hospitals in late December 2014, indicating the urgent need for an epidemic outbreak investigation. Methods We conducted a prospective study of pneumonia etiology among immunocompetent young adults admitted to Daejeon Armed Forces hospital. Patient blood and sputum samples were subjected to conventional culture, serology, and polymerase chain reaction tests for respiratory viruses and atypical pathogens. Results From January to May 2015, we enrolled 191 (189 male) adults with pneumonia; the mean age was 20.1 ± 1.3 years. Five patients had severe pneumonia, and one died. Pathogenic human adenoviruses were most common (HAdV, 153/191 [80.1%]), indicating a HAdV pneumonia outbreak. Genotyping of 35 isolates indicated that 34 matched HAdV-55 and one matched HAdV-2. HAdV pneumonia infected recruit trainees most frequently. High and prolonged fever, nasal congestion, sore throat, and pharyngeal inflammation were significantly more common in the HAdV pneumonia group, compared to patients with other or unknown causes of pneumonia. Only 12% of HAdV pneumonia patients displayed leukocytosis, whereas febrile leukopenia (62.7%) and thrombocytopenia (41%) were commonly observed. HAdV pneumonia patient chest CT scans displayed ground glass opacity (with or without septal thickness) with consolidation in 50.0% of patients. Conclusions An outbreak of HAdV respiratory infection occurred at the Korean military training center. HAdV pneumonia exhibited specific laboratory and clinical features, and although most patients were cured without complication, some progressed to respiratory failure and fatality. Therefore, HAdV vaccine should be provided to military trainees in Korea.
Collapse
Affiliation(s)
- Ji Young Park
- Division of Pulmonary, Allergy and Critical Care Medicine, Department of Internal Medicine, Hallym University Sacred Heart Hospital, Anyang, Korea
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, The Armed Forces Daejeon Hospital, Daejeon, Korea
| | - Bong-Joon Kim
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, The Armed Forces Daejeon Hospital, Daejeon, Korea
- Department of Internal Medicine, Kosin University College of Medicine, Busan, Korea
| | - Eun Jung Lee
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, The Armed Forces Daejeon Hospital, Daejeon, Korea
| | - Kwi Sung Park
- Chungcheongnam-Do Institute of Health and Environment Research, Daejeon, Korea
| | - Hee Sun Park
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Chungnam National University Hospital, Daejeon, Korea
| | - Sung Soo Jung
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Chungnam National University Hospital, Daejeon, Korea
| | - Ju Ock Kim
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Chungnam National University Hospital, Daejeon, Korea
- * E-mail:
| |
Collapse
|
7
|
Pang J, Jin J, Loh JP, Tan BH, Koh WHV, Ng SH, Ho ZJM, Gao Q, Cook AR, Hsu LY, Lee VJ, Chen MIC. Risk factors for febrile respiratory illness and mono-viral infections in a semi-closed military environment: a case-control study. BMC Infect Dis 2015. [PMID: 26208494 PMCID: PMC4514976 DOI: 10.1186/s12879-015-1024-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Background Febrile respiratory illness (FRI) results in substantial burden in semi-closed environments. Tackling risk factors may reduce transmission and infection. However, risk factors involved in one setting may not be generalizable in all settings due to differences in climate, residential environment, population genetic and cultural backgrounds. This study aims to identify risk factors of FRI and mono-viral infections in a tropical military environment. Methods From year 2009 to 2012, military personnel with temperature ≥37.5 °C, cough and/or sore throat, and personnel with no fever or no respiratory symptoms were recruited as cases and controls, respectively. Subjects provided nasal wash specimens and answered a standardized questionnaire. Resplex assays were used to determine the viral etiologies. Descriptive, univariate and multivariate analyses of the variables were performed using appropriate descriptive tests and logistic regression modelling, respectively, with R program. Results A total of 7,743 FRI cases and 1,247 non-FRI study controls were recruited. Increasing age [adjusted odds ratio (AOR) = 1.03; 95 % confidence interval (CI) = 1.01-1.05], recruit camp (AOR = 4.67; 95 % CI = 3.99-5.46) and smoker (AOR = 1.31; 95 % CI = 1.13-1.52) were independent risk factors of FRI. Malay ethnicity was positively associated with influenza A(H1N1)pdm09 (AOR = 1.50; 95 % CI = 1.04-2.15) and coxsackie/echovirus (AOR = 1.67; 95 % CI = 1.19-2.36) mono-infection. Significant contact risk factors were stay-out personnel with ill household member (AOR = 4.96; 95 % CI = 3.39-7.24), and stay-in personnel with ill bunkmate and household member (AOR = 3.55; 95 % CI = 2.57-4.91). Staying in camp with none ill in bunk and at home was a protective factor against FRI (AOR = 0.80; 95 % CI = 0.64-0.99). These contact risk factors were similarly observed for the five most common viruses detected, namely adenovirus, rhinoviruses, influenza A and B, and coxsackie/echovirus. Conclusion Increasing age, smoker, recruit-camp, stay-out personnel with ill household members and stay-in personnel with ill bunkmates were independent risk factors of FRI in a semi-closed military environment. Early identification and isolation of ill personnel from their bunk may be effective to prevent and reduce transmission and disease burden.
Collapse
Affiliation(s)
- Junxiong Pang
- Centre for Infectious Disease Epidemiology and Research, Saw Swee Hock School of Public Health, National University of Singapore, Singapore, Singapore. .,Communicable Disease Centre, Institute of Infectious Diseases and Epidemiology, Tan Tock Seng Hospital, Singapore, Singapore.
| | - Jing Jin
- Centre for Infectious Disease Epidemiology and Research, Saw Swee Hock School of Public Health, National University of Singapore, Singapore, Singapore.
| | - Jin Phang Loh
- Defence Medical and Environmental Research Institute, Singapore, Singapore.
| | - Boon Huan Tan
- Defence Medical and Environmental Research Institute, Singapore, Singapore.
| | | | - Sock Hoon Ng
- Defence Medical and Environmental Research Institute, Singapore, Singapore.
| | | | - Qiuhan Gao
- Biodefence Centre, Ministry of Defence, Singapore, Singapore.
| | - Alex R Cook
- Centre for Infectious Disease Epidemiology and Research, Saw Swee Hock School of Public Health, National University of Singapore, Singapore, Singapore. .,Yale-NUS College, National University of Singapore, Singapore, Singapore. .,Program in Health Services and Systems Research, Duke-NUS Graduate Medical School, Singapore, Singapore. .,Department of Statistics and Applied Probability, National University of Singapore, Singapore, Singapore.
| | - Li Yang Hsu
- Centre for Infectious Disease Epidemiology and Research, Saw Swee Hock School of Public Health, National University of Singapore, Singapore, Singapore. .,Department of Medicine, National University of Singapore, Singapore, Singapore.
| | - Vernon J Lee
- Biodefence Centre, Ministry of Defence, Singapore, Singapore.
| | - Mark I Cheng Chen
- Centre for Infectious Disease Epidemiology and Research, Saw Swee Hock School of Public Health, National University of Singapore, Singapore, Singapore. .,Communicable Disease Centre, Institute of Infectious Diseases and Epidemiology, Tan Tock Seng Hospital, Singapore, Singapore.
| |
Collapse
|
8
|
Sanchez JL, Cooper MJ, Myers CA, Cummings JF, Vest KG, Russell KL, Sanchez JL, Hiser MJ, Gaydos CA. Respiratory Infections in the U.S. Military: Recent Experience and Control. Clin Microbiol Rev 2015; 28:743-800. [PMID: 26085551 PMCID: PMC4475643 DOI: 10.1128/cmr.00039-14] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
This comprehensive review outlines the impact of military-relevant respiratory infections, with special attention to recruit training environments, influenza pandemics in 1918 to 1919 and 2009 to 2010, and peacetime operations and conflicts in the past 25 years. Outbreaks and epidemiologic investigations of viral and bacterial infections among high-risk groups are presented, including (i) experience by recruits at training centers, (ii) impact on advanced trainees in special settings, (iii) morbidity sustained by shipboard personnel at sea, and (iv) experience of deployed personnel. Utilizing a pathogen-by-pathogen approach, we examine (i) epidemiology, (ii) impact in terms of morbidity and operational readiness, (iii) clinical presentation and outbreak potential, (iv) diagnostic modalities, (v) treatment approaches, and (vi) vaccine and other control measures. We also outline military-specific initiatives in (i) surveillance, (ii) vaccine development and policy, (iii) novel influenza and coronavirus diagnostic test development and surveillance methods, (iv) influenza virus transmission and severity prediction modeling efforts, and (v) evaluation and implementation of nonvaccine, nonpharmacologic interventions.
Collapse
Affiliation(s)
- Jose L Sanchez
- Armed Forces Health Surveillance Center, Silver Spring, Maryland, USA
| | - Michael J Cooper
- Armed Forces Health Surveillance Center, Silver Spring, Maryland, USA
| | | | - James F Cummings
- Armed Forces Health Surveillance Center, Silver Spring, Maryland, USA
| | - Kelly G Vest
- Armed Forces Health Surveillance Center, Silver Spring, Maryland, USA
| | - Kevin L Russell
- Armed Forces Health Surveillance Center, Silver Spring, Maryland, USA
| | - Joyce L Sanchez
- Mayo Clinic, Division of General Internal Medicine, Rochester, Minnesota, USA
| | - Michelle J Hiser
- Armed Forces Health Surveillance Center, Silver Spring, Maryland, USA Oak Ridge Institute for Science and Education, Postgraduate Research Participation Program, U.S. Army Public Health Command, Aberdeen Proving Ground, Aberdeen, Maryland, USA
| | - Charlotte A Gaydos
- International STD, Respiratory, and Biothreat Research Laboratory, Division of Infectious Diseases, Johns Hopkins University, Baltimore, Maryland, USA
| |
Collapse
|
9
|
Radin JM, Hawksworth AW, Blair PJ, Faix DJ, Raman R, Russell KL, Gray GC. Dramatic decline of respiratory illness among US military recruits after the renewed use of adenovirus vaccines. Clin Infect Dis 2014; 59:962-8. [PMID: 24991024 DOI: 10.1093/cid/ciu507] [Citation(s) in RCA: 84] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND In late 2011, after a 12-year hiatus, oral vaccines against adenovirus types 4 (Ad4) and 7 (Ad7) were again produced and administered to US military recruits. This study examined the impact of the new adenovirus vaccines on febrile respiratory illness (FRI) and adenovirus rates and investigated if new serotypes emerged. FRI rates and their associated hospitalizations had markedly risen since vaccine production ceased in 1999. METHODS From 1996 to 2013, the Naval Health Research Center conducted FRI surveillance at 8 military recruit training centers in the United States. During this period, 58 103 FRI pharyngeal swab specimens were studied, yielding 37 048 adenovirus-positive cases, among which 64% were typed. RESULTS During the 2 years after reintroduction of the vaccines, military trainees experienced a 100-fold decline in adenovirus disease burden (from 5.8 to 0.02 cases per 1000 person-weeks, P < .0001), without evidence that vaccine pressure had increased the impact of adenovirus types other than Ad4 and Ad7. Although the percentage of type 14 increased following reintroduction of the vaccination, the actual number of cases decreased. We estimate that the vaccines prevent approximately 1 death, 1100-2700 hospitalizations, and 13 000 febrile adenovirus cases each year among the trainees. CONCLUSIONS These data strongly support the continued production and use of Ad4 and Ad7 vaccines in controlling FRI among US military trainees. Continued surveillance for emerging adenovirus subtypes is warranted.
Collapse
Affiliation(s)
- Jennifer M Radin
- Operational Infectious Diseases Department, Naval Health Research Center Joint Doctoral Program in Public Health (Epidemiology), San Diego State University/University of California
| | | | - Patrick J Blair
- Operational Infectious Diseases Department, Naval Health Research Center
| | - Dennis J Faix
- Deployment Health Research Department, Naval Health Research Center
| | - Rema Raman
- Department of Family and Preventive Medicine, University of California, San Diego
| | - Kevin L Russell
- Armed Forces Health Surveillance Center, Silver Spring, Maryland
| | - Gregory C Gray
- College of Public Health and Health Professions Emerging Pathogens Institute, University of Florida, Gainesville
| |
Collapse
|
10
|
Abstract
Human rhinoviruses (HRVs), first discovered in the 1950s, are responsible for more than one-half of cold-like illnesses and cost billions of dollars annually in medical visits and missed days of work. Advances in molecular methods have enhanced our understanding of the genomic structure of HRV and have led to the characterization of three genetically distinct HRV groups, designated groups A, B, and C, within the genus Enterovirus and the family Picornaviridae. HRVs are traditionally associated with upper respiratory tract infection, otitis media, and sinusitis. In recent years, the increasing implementation of PCR assays for respiratory virus detection in clinical laboratories has facilitated the recognition of HRV as a lower respiratory tract pathogen, particularly in patients with asthma, infants, elderly patients, and immunocompromised hosts. Cultured isolates of HRV remain important for studies of viral characteristics and disease pathogenesis. Indeed, whether the clinical manifestations of HRV are related directly to viral pathogenicity or secondary to the host immune response is the subject of ongoing research. There are currently no approved antiviral therapies for HRVs, and treatment remains primarily supportive. This review provides a comprehensive, up-to-date assessment of the basic virology, pathogenesis, clinical epidemiology, and laboratory features of and treatment and prevention strategies for HRVs.
Collapse
Affiliation(s)
- Samantha E. Jacobs
- Transplantation-Oncology Infectious Diseases Program, Division of Infectious Diseases, Weill Cornell Medical College, New York, New York, USA
| | - Daryl M. Lamson
- Laboratory of Viral Diseases, Wadsworth Center, Albany, New York, USA
| | | | - Thomas J. Walsh
- Transplantation-Oncology Infectious Diseases Program, Division of Infectious Diseases, Weill Cornell Medical College, New York, New York, USA
| |
Collapse
|
11
|
White DW, Feigley CE, McKeown RE, Hout JJ, Hebert JR. Association between barracks type and acute respiratory infection in a gender integrated Army basic combat training population. Mil Med 2011; 176:909-14. [PMID: 21882781 DOI: 10.7205/milmed-d-10-00418] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
BACKGROUND Acute respiratory infections (ARIs) are the leading cause of acute morbidity and lost work time in the United States. Few studies have looked at building design and transmission of ARIs. OBJECTIVES This study explores the association of ventilation design, room occupancy numbers, and training week with ARI rates in Army Basic Combat Training barracks. METHODS This observational study captured the overall incidence of ARI in a cohort of 16,258 individuals attending basic combat training at Fort Jackson, South Carolina. RESULTS ARI risk was higher among trainees living in the 60-person room barracks compared with those living in 8-person rooms, which increased rapidly for the first few weeks of training and then declined to baseline. CONCLUSIONS Findings support direct contact as primary ARI transmission mode in this study population based on observed lower ARI risk in smaller room barracks and similar risk in large room barracks despite heating, ventilation, and air conditioning system variability.
Collapse
Affiliation(s)
- Duvel W White
- Division of Occupational and Environmental Science, Department of Preventive Medicine and Biometrics, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Road, Bethesda, MD 20814-4799, USA
| | | | | | | | | |
Collapse
|
12
|
Jefferson T, Del Mar CB, Dooley L, Ferroni E, Al‐Ansary LA, Bawazeer GA, van Driel ML, Nair NS, Jones MA, Thorning S, Conly JM. Physical interventions to interrupt or reduce the spread of respiratory viruses. Cochrane Database Syst Rev 2011; 2011:CD006207. [PMID: 21735402 PMCID: PMC6993921 DOI: 10.1002/14651858.cd006207.pub4] [Citation(s) in RCA: 242] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND Viral epidemics or pandemics of acute respiratory infections like influenza or severe acute respiratory syndrome pose a global threat. Antiviral drugs and vaccinations may be insufficient to prevent their spread. OBJECTIVES To review the effectiveness of physical interventions to interrupt or reduce the spread of respiratory viruses. SEARCH STRATEGY We searched The Cochrane Library, the Cochrane Central Register of Controlled Trials (CENTRAL 2010, Issue 3), which includes the Acute Respiratory Infections Group's Specialised Register, MEDLINE (1966 to October 2010), OLDMEDLINE (1950 to 1965), EMBASE (1990 to October 2010), CINAHL (1982 to October 2010), LILACS (2008 to October 2010), Indian MEDLARS (2008 to October 2010) and IMSEAR (2008 to October 2010). SELECTION CRITERIA In this update, two review authors independently applied the inclusion criteria to all identified and retrieved articles and extracted data. We scanned 3775 titles, excluded 3560 and retrieved full papers of 215 studies, to include 66 papers of 67 studies. We included physical interventions (screening at entry ports, isolation, quarantine, social distancing, barriers, personal protection, hand hygiene) to prevent respiratory virus transmission. We included randomised controlled trials (RCTs), cohorts, case-controls, before-after and time series studies. DATA COLLECTION AND ANALYSIS We used a standardised form to assess trial eligibility. We assessed RCTs by randomisation method, allocation generation, concealment, blinding and follow up. We assessed non-RCTs for potential confounders and classified them as low, medium and high risk of bias. MAIN RESULTS We included 67 studies including randomised controlled trials and observational studies with a mixed risk of bias. A total number of participants is not included as the total would be made up of a heterogenous set of observations (participant people, observations on participants and countries (object of some studies)). The risk of bias for five RCTs and most cluster-RCTs was high. Observational studies were of mixed quality. Only case-control data were sufficiently homogeneous to allow meta-analysis. The highest quality cluster-RCTs suggest respiratory virus spread can be prevented by hygienic measures, such as handwashing, especially around younger children. Benefit from reduced transmission from children to household members is broadly supported also in other study designs where the potential for confounding is greater. Nine case-control studies suggested implementing transmission barriers, isolation and hygienic measures are effective at containing respiratory virus epidemics. Surgical masks or N95 respirators were the most consistent and comprehensive supportive measures. N95 respirators were non-inferior to simple surgical masks but more expensive, uncomfortable and irritating to skin. Adding virucidals or antiseptics to normal handwashing to decrease respiratory disease transmission remains uncertain. Global measures, such as screening at entry ports, led to a non-significant marginal delay in spread. There was limited evidence that social distancing was effective, especially if related to the risk of exposure. AUTHORS' CONCLUSIONS Simple and low-cost interventions would be useful for reducing transmission of epidemic respiratory viruses. Routine long-term implementation of some measures assessed might be difficult without the threat of an epidemic.
Collapse
Affiliation(s)
- Tom Jefferson
- University of OxfordCentre for Evidence Based MedicineOxfordUKOX2 6GG
| | - Chris B Del Mar
- Bond UniversityCentre for Research in Evidence‐Based Practice (CREBP)University DriveGold CoastQueenslandAustralia4229
| | - Liz Dooley
- Bond UniversityFaculty of Health Sciences and MedicineGold CoastQueenslandAustralia4229
| | - Eliana Ferroni
- Regional Center for Epidemiology, Veneto RegionEpidemiological System of the Veneto RegionPassaggio Gaudenzio 1PadovaItaly35131
| | - Lubna A Al‐Ansary
- World Health OrganizationDepartment of Health Metrics and MeasurementGenevaSwitzerland
| | - Ghada A Bawazeer
- King Saud UniversityDepartment of Clinical Pharmacy, College of PharmacyP.O. Box 22452RiyadhSaudi Arabia11495
| | - Mieke L van Driel
- The University of QueenslandPrimary Care Clinical Unit, Faculty of MedicineBrisbaneQueenslandAustralia4029
- Ghent UniversityDepartment of Public Health and Primary CareCampus UZ 6K3, Corneel Heymanslaan 10GhentBelgium9000
| | - N Sreekumaran Nair
- Jawaharlal Institute of Postgraduate Medical Education and Research (JIPMER) (Institution of National Importance Under Ministry of Health and Family Welfare, Government of India)Department of Medical Biometrics & Informatics (Biostatistics)4th Floor, Administrative BlockDhanvantri NagarPuducherryIndia605006
| | - Mark A Jones
- Bond UniversityInstitute for Evidence‐Based Healthcare11 University DriveRobinaGold CoastQueenslandAustralia4226
| | - Sarah Thorning
- Gold Coast Hospital and Health ServiceGCUH LibraryLevel 1, Block E, GCUHSouthportQueenslandAustralia4215
| | - John M Conly
- Foothills Medical Centre, Room 930, North Tower1403‐29th St NWCalgaryABCanadaT2N 2T9
- WHO. Infection Prevention and Control in Health CareDepartment of Global Alert and Response ‐ Health Security and EnvironmentOffice L420, 20, Avenue AppiaGenevaSwitzerlandCH‐1211
| | | |
Collapse
|
13
|
Jefferson T, Del Mar C, Dooley L, Ferroni E, Al-Ansary LA, Bawazeer GA, van Driel ML, Nair S, Foxlee R, Rivetti A. Physical interventions to interrupt or reduce the spread of respiratory viruses. Cochrane Database Syst Rev 2010:CD006207. [PMID: 20091588 DOI: 10.1002/14651858.cd006207.pub3] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND Viral epidemics or pandemics of acute respiratory infections like influenza or severe acute respiratory syndrome pose a world-wide threat. Antiviral drugs and vaccinations may be insufficient to prevent catastrophe. OBJECTIVES To systematically review the effectiveness of physical interventions to interrupt or reduce the spread of respiratory viruses. SEARCH STRATEGY We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2009, issue 2); MEDLINE (1966 to May 2009); OLDMEDLINE (1950 to 1965); EMBASE (1990 to May 2009); and CINAHL (1982 to May 2009). SELECTION CRITERIA We scanned 2958 titles, excluded 2790 and retrieved the full papers of 168 trials, to include 59 papers of 60 studies. We included any physical interventions (isolation, quarantine, social distancing, barriers, personal protection and hygiene) to prevent transmission of respiratory viruses. We included the following study designs: randomised controlled trials (RCTs), cohorts, case controls, cross-over, before-after, and time series studies. DATA COLLECTION AND ANALYSIS We used a standardised form to assess trial eligibility. RCTs were assessed by: randomisation method; allocation generation; concealment; blinding; and follow up. Non-RCTs were assessed for the presence of potential confounders, and classified into low, medium, and high risks of bias. MAIN RESULTS The risk of bias for the four RCTs, and most cluster RCTs, was high. The observational studies were of mixed quality. Only case-control data were sufficiently homogeneous to allow meta-analysis.The highest quality cluster RCTs suggest respiratory virus spread can be prevented by hygienic measures, such as handwashing, especially around younger children. Additional benefit from reduced transmission from children to other household members is broadly supported in results of other study designs, where the potential for confounding is greater. Six case-control studies suggested that implementing barriers to transmission, isolation, and hygienic measures are effective at containing respiratory virus epidemics. We found limited evidence that N95 respirators were superior to simple surgical masks, but were more expensive, uncomfortable, and caused skin irritation. The incremental effect of adding virucidals or antiseptics to normal handwashing to decrease respiratory disease remains uncertain. Global measures, such as screening at entry ports, were not properly evaluated. There was limited evidence that social distancing was effective especially if related to the risk of exposure. AUTHORS' CONCLUSIONS Many simple and probably low-cost interventions would be useful for reducing the transmission of epidemic respiratory viruses. Routine long-term implementation of some of the measures assessed might be difficult without the threat of a looming epidemic.
Collapse
Affiliation(s)
- Tom Jefferson
- Vaccines Field, The Cochrane Collaboration, Via Adige 28a, Anguillara Sabazia, Roma, Italy, 00061
| | | | | | | | | | | | | | | | | | | |
Collapse
|
14
|
Jefferson T, Del Mar C, Dooley L, Ferroni E, Al-Ansary LA, Bawazeer GA, van Driel ML, Foxlee R, Rivetti A. Physical interventions to interrupt or reduce the spread of respiratory viruses: systematic review. BMJ 2009; 339:b3675. [PMID: 19773323 PMCID: PMC2749164 DOI: 10.1136/bmj.b3675] [Citation(s) in RCA: 186] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
OBJECTIVE To review systematically the evidence of effectiveness of physical interventions to interrupt or reduce the spread of respiratory viruses. DATA SOURCES Cochrane Library, Medline, OldMedline, Embase, and CINAHL, without restrictions on language or publication. Data selection Studies of any intervention to prevent the transmission of respiratory viruses (isolation, quarantine, social distancing, barriers, personal protection, and hygiene). A search of study designs included randomised trials, cohort, case-control, crossover, before and after, and time series studies. After scanning of the titles, abstracts and full text articles as a first filter, a standardised form was used to assess the eligibility of the remainder. Risk of bias of randomised studies was assessed for generation of the allocation sequence, allocation concealment, blinding, and follow-up. Non-randomised studies were assessed for the presence of potential confounders and classified as being at low, medium, or high risk of bias. DATA SYNTHESIS 58 papers of 59 studies were included. The quality of the studies was poor for all four randomised controlled trials and most cluster randomised controlled trials; the observational studies were of mixed quality. Meta-analysis of six case-control studies suggested that physical measures are highly effective in preventing the spread of severe acute respiratory syndrome: handwashing more than 10 times daily (odds ratio 0.45, 95% confidence interval 0.36 to 0.57; number needed to treat=4, 95% confidence interval 3.65 to 5.52), wearing masks (0.32, 0.25 to 0.40; NNT=6, 4.54 to 8.03), wearing N95 masks (0.09, 0.03 to 0.30; NNT=3, 2.37 to 4.06), wearing gloves (0.43, 0.29 to 0.65; NNT=5, 4.15 to 15.41), wearing gowns (0.23, 0.14 to 0.37; NNT=5, 3.37 to 7.12), and handwashing, masks, gloves, and gowns combined (0.09, 0.02 to 0.35; NNT=3, 2.66 to 4.97). The combination was also effective in interrupting the spread of influenza within households. The highest quality cluster randomised trials suggested that spread of respiratory viruses can be prevented by hygienic measures in younger children and within households. Evidence that the more uncomfortable and expensive N95 masks were superior to simple surgical masks was limited, but they caused skin irritation. The incremental effect of adding virucidals or antiseptics to normal handwashing to reduce respiratory disease remains uncertain. Global measures, such as screening at entry ports, were not properly evaluated. Evidence was limited for social distancing being effective, especially if related to risk of exposure-that is, the higher the risk the longer the distancing period. CONCLUSION Routine long term implementation of some of the measures to interrupt or reduce the spread of respiratory viruses might be difficult. However, many simple and low cost interventions reduce the transmission of epidemic respiratory viruses. More resources should be invested into studying which physical interventions are the most effective, flexible, and cost effective means of minimising the impact of acute respiratory tract infections.
Collapse
Affiliation(s)
- Tom Jefferson
- Acute Respiratory Infections Group, Cochrane Collaboration, Rome, Italy.
| | | | | | | | | | | | | | | | | |
Collapse
|
15
|
Sanchez J, Gaydos J. Respiratory Disease, the Environment, and the Military: Important, Unexplored Frontiers. J Infect Dis 2008; 198:1417-9. [DOI: 10.1086/592712] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
|