Incubation periods of acute respiratory viral infections: A systematic review

Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA.
The Lancet Infectious Diseases (Impact Factor: 22.43). 06/2009; 9(5):291-300. DOI: 10.1016/S1473-3099(09)70069-6
Source: PubMed


Knowledge of the incubation period is essential in the investigation and control of infectious disease, but statements of incubation period are often poorly referenced, inconsistent, or based on limited data. In a systematic review of the literature on nine respiratory viral infections of public-health importance, we identified 436 articles with statements of incubation period and 38 with data for pooled analysis. We fitted a log-normal distribution to pooled data and found the median incubation period to be 5.6 days (95% CI 4.8-6.3) for adenovirus, 3.2 days (95% CI 2.8-3.7) for human coronavirus, 4.0 days (95% CI 3.6-4.4) for severe acute respiratory syndrome coronavirus, 1.4 days (95% CI 1.3-1.5) for influenza A, 0.6 days (95% CI 0.5-0.6) for influenza B, 12.5 days (95% CI 11.8-13.3) for measles, 2.6 days (95% CI 2.1-3.1) for parainfluenza, 4.4 days (95% CI 3.9-4.9) for respiratory syncytial virus, and 1.9 days (95% CI 1.4-2.4) for rhinovirus. When using the incubation period, it is important to consider its full distribution: the right tail for quarantine policy, the central regions for likely times and sources of infection, and the full distribution for models used in pandemic planning. Our estimates combine published data to give the detail necessary for these and other applications.

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    • "In spite of these epidemiological consequences, precise estimates of the mismatch between the ends of the incubation and latent periods are scarce in the scientific literature. Information on both periods is available for several human diseases (Anderson and May 1992; Bailey 1954; Johansson et al. 2010; Lee et al. 2013; Lessler et al. 2009). However, such data are often approximate (Chan and Johansson 2012), because for obvious ethical reasons most of the related studies are based on observations of naturally infected patients (often resulting in censored data since the infection date is rarely known) and rarely on experimental data. "
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    Phytopathology 10/2015; 105(11):PHYTO01150014R. DOI:10.1094/PHYTO-01-15-0014-R · 3.12 Impact Factor
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    • "In addition, the short follow-up duration of this trial means there is a possible failure to detect some infections. The incubation period of respiratory viruses may range from less than 2 days (e.g., rhinovirus and influenza) to more than 5 days (adenovirus, MERS-CoV) [30] [31]. However, it is believed that post-Hajj Health diaries will reduce this shortcoming to some extent. "
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    • "The present study utilized a case-crossover design which is most suitable for studying relations with the following characteristics: 1) the individual exposure varies within short time intervals; 2) the disease has abrupt onset and short latency for detection; and 3) the induction period is short [17]. For ambient temperature and AH the hazard period was defined as three days preceding the visit to the clinic for a respiratory infection (and when virological samples were collected) on the basis of the estimated incubation period of 1–2 days for influenza [18]. A symmetric bidirectional selection of two reference periods shortly before and after the hazard period was utilized [19]. "
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