Reconstructing the household transmission of influenza in the suburbs of Tokyo based on clinical cases

Abstract Background Influenza is a public health issue that needs to be addressed strategically. The assessment of detailed infectious profiles is an important part of this effort. Household transmission data play a key role in estimating such profiles. We used diagnostic and questionnaire-based data on influenza patients at a Japanese clinic to estimate the detailed infectious period (as well as incubation period, symptomatic and infectious periods, and extended infectious period after recovery) and the secondary attack ratio (SAR) of influenza for households of various sizes based on a modified Cauchemez-type model. Results The data were from enrolled patients with confirmed influenza who were treated at the Hirotsu Clinic (Kawasaki, Japan) with a neuraminidase inhibitor (NAI) during six northern hemisphere influenza seasons between 2010 and 2016. A total of 2342 outpatients, representing 1807 households, were included. For influenza type A, the average incubation period was 1.43 days (95% probability interval, 0.03–5.32 days). The estimated average symptomatic and infective period was 1.76 days (0.33–4.62 days); the extended infective period after recovery was 0.25 days. The estimated SAR rose from 20 to 32% as household size increased from 3 to 5. For influenza type B, the average incubation period, average symptomatic and infective period, and extended infective period were estimated as 1.66 days (0.21–4.61), 2.62 days (0.54–5.75) and 1.00 days, respectively. The SAR increased from 12 to 21% as household size increased from 3 to 5. Conclusion All estimated periods of influenza type B were longer than the corresponding periods for type A. However, the SAR for type B was less than that for type A. These results may reflect Japanese demographics and treatment policy. Understanding the infectious profiles of influenza is necessary for assessing public health measures.

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Reconstructing the Household Transmission of Influenza in the Suburbs of Tokyo Based on Clinical Cases

10.21203/rs.3.rs-37881/v1 ◽

2020 ◽

Author(s):

Masaya Masayoshi Saito ◽

Nobuo Hirotsu ◽

Hiroka Hamada ◽

Mio Takei ◽

Keisuke Honda ◽

...

Keyword(s):

Public Health ◽

Incubation Period ◽

Type A ◽

Household Size ◽

Infectious Period ◽

Public Health Issue ◽

Type B ◽

Influenza Type ◽

Household Transmission ◽

Infective Period

Abstract Background Influenza is a public health issue that needs to be addressed strategically and assessment of detailed infectious profiles is important for that. Household transmission data have played a key role for estimating these profiles. From one clinic’s influenza diagnostic and questionnaire-based data, we aimed to estimate the detailed infectious period (incubation, symptomatic and infective, and extended infective after recovery) and secondary attack ratio (SAR) for each household size of influenza by using modified Cauchemez-type model.Results The data source was derived from enrolled patients with confirmed influenza who were treated at the Hirotsu Clinic (Kawasaki, Japan) with a neuraminidase inhibitor (NAI) during the 6 Northern Hemisphere influenza seasons between 2010 and 2016. A total of 2,342 outpatients representing 1,807 households were included. For influenza type A, average incubation period and its 95% probability interval was 1.43 (0.03-5.32) days. Estimated average symptomatic and infective period was 1.76 (0.33-4.62) days and point estimated extended infective period after recovery was 0.25 days. Estimated SAR elevated from 20% to 32% as household size increases from 3 to 5. For influenza type B, average incubation period, average symptomatic and infective period, and extended infective period were estimated 1.66 (0.21-4.61) days, 2.62 (0.54-5.75) days and 1.00 days, respectively. SAR was increased 12% to 21% as household size increases from 3 to 5.Conclusion All estimated periods of influenza type B were longer than those of influenza type A. On the other hands, SAR of type B was less than that of type A. These results may reflect Japanese demographics and treatment policy. It is useful to understand the infectious profiles of influenza for examining public health measures.

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Reconstructing the household transmission of influenza in the suburbs of Tokyo based on clinical cases

10.21203/rs.3.rs-37881/v2 ◽

2021 ◽

Author(s):

Masaya Masayoshi Saito ◽

Nobuo Hirotsu ◽

Hiroka Hamada ◽

Mio Takei ◽

Keisuke Honda ◽

...

Keyword(s):

Public Health ◽

Incubation Period ◽

Type A ◽

Household Size ◽

Infectious Period ◽

Public Health Issue ◽

Type B ◽

Influenza Type ◽

Household Transmission ◽

Infective Period

Abstract BackgroundInfluenza is a public health issue that needs to be addressed strategically. The assessment of detailed infectious profiles is an important part of this effort. Household transmission data play a key role in estimating such profiles. We used diagnostic and questionnaire-based data on influenza patients at a Japanese clinic to estimate the detailed infectious period (as well as incubation period, symptomatic and infectious periods, and extended infectious period after recovery) and the secondary attack ratio (SAR) of influenza for households of various sizes based on a modified Cauchemez-type model.ResultsThe data were from enrolled patients with confirmed influenza who were treated at the Hirotsu Clinic (Kawasaki, Japan) with a neuraminidase inhibitor (NAI) during six northern hemisphere influenza seasons between 2010 and 2016. A total of 2,342 outpatients, representing 1,807 households, were included. For influenza type A, the average incubation period was 1.43 days (95% probability interval: 0.03-5.32 days). The estimated average symptomatic and infective period was 1.76 days (0.33-4.62 days); the extended infective period after recovery was 0.25 days. The estimated SAR rose from 20% to 32% as household size increased from 3 to 5. For influenza type B, the average incubation period, average symptomatic and infective period, and extended infective period were estimated as 1.66 days (0.21-4.61), 2.62 days (0.54-5.75) and 1.00 days, respectively. The SAR increased from 12% to 21% as household size increased from 3 to 5.ConclusionAll estimated periods of influenza type B were longer than the corresponding periods for type A. However, the SAR for type B was less than that for type A. These results may reflect Japanese demographics and treatment policy. Understanding the infectious profiles of influenza is necessary for assessing public health measures.

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The Correlation of IFN <i>γ</i> to the Preferential Isolation of Influenza Type B over Type A Viruses in Madin Darby Canine Kidney Cells

Open Journal of Medical Microbiology ◽

10.4236/ojmm.2017.71002 ◽

2017 ◽

Vol 07 (01) ◽

pp. 12-28

Author(s):

Timothy Byaruhanga ◽

Bernard Bagaya ◽

Joyce Namulondo ◽

John Timothy Kayiwa ◽

Barbara Namagambo ◽

...

Keyword(s):

Type A ◽

Kidney Cells ◽

Type B ◽

Madin Darby Canine Kidney ◽

Influenza Type ◽

Darby Canine Kidney ◽

Canine Kidney

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The basics of infection microbiology

10.1093/med/9780198745471.003.0004 ◽

2016 ◽

Author(s):

Paul Shears ◽

David Harvey

Keyword(s):

Public Health ◽

Antimicrobial Resistance ◽

Natural History ◽

Incubation Period ◽

Health Management ◽

Molecular Techniques ◽

Diagnostic Methods ◽

History Of ◽

Infective Period ◽

Public Health Management

This chapter outlines the natural history of infections caused by a variety of organisms. These organisms may already colonize a patient (endogenous) or come from another source (exogenous). They vary in the time it takes to cause symptoms (incubation period). Some are more infective than others, and the infective period varies depending on the organism. A range of diagnostic methods are used to identify the disease, from growing the organism (culture) to using molecular techniques to identify characteristics unique to the organism. Understanding what is causing an infection is important in public health management to support outbreak identification and management. Advanced techniques can identify whether the organism is likely to be transmitted from one individual to another. Antimicrobial resistance is becoming more and more problematic and can lead to difficulties of treatment of even simple infections.

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United States Healthcare Costs for Illness Attributable to Seasonal Influenza Type A and Type B During 2001/2002–2008/2009

Open Forum Infectious Diseases ◽

10.1093/ofid/ofv133.867 ◽

2015 ◽

Vol 2 (suppl_1) ◽

Author(s):

Songkai Yan ◽

Derek Weycker ◽

Stephania Sokolowski ◽

Girishanthy Krishnarajah

Keyword(s):

United States ◽

Healthcare Costs ◽

Seasonal Influenza ◽

Type A ◽

Type B ◽

Influenza Type ◽

United States Healthcare

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Eleven Cases of Co-infection with Influenza Type A and Type B Suspected by Use of a Rapid Diagnostic Kit and Confirmed by RT-PCR and Virus Isolation

Kansenshogaku zasshi ◽

10.11150/kansenshogakuzasshi1970.79.877 ◽

2005 ◽

Vol 79 (11) ◽

pp. 877-886 ◽

Cited By ~ 8

Author(s):

Shinichi TAKAO ◽

Michimaru HARA ◽

Osamu KAKUTA ◽

Yukie SHIMAZU ◽

Masaru KUWAYAMA ◽

...

Keyword(s):

Virus Isolation ◽

Type A ◽

Type B ◽

Rt Pcr ◽

Influenza Type

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Evaluation of the diagnostic utility of case definitions to detect influenza virus infection in Vojvodina, Serbia

Srpski arhiv za celokupno lekarstvo ◽

10.2298/sarh180117068r ◽

2020 ◽

Vol 148 (1-2) ◽

pp. 100-105

Author(s):

Mioljub Ristic ◽

Vladimir Petrovic

Keyword(s):

Type A ◽

Case Definition ◽

World Health ◽

Influenza Surveillance ◽

Age Group ◽

Type B ◽

Case Definitions ◽

Influenza Type ◽

Epidemic Period ◽

Definition Of

Introduction/Objective. A case definition recommended by the World Health Organization is commonly used for influenza surveillance worldwide. The aim of this study was to evaluate prognostic values of proposed case definitions of Influenza Like Illness (ILI), Severe Acute Respiratory Illness (SARI) and Acute Respiratory Distress Syndrome (ARDS) for laboratory confirmed-influenza and to compare the age distribution of influenza patients across virus types and subtypes in Vojvodina. Methods. We conducted a descriptive epidemiological study using surveillance reports and laboratory data from October 1, 2010 to May 20, 2017 (seven surveillance seasons). Results. We included 2,937 participants, 48.6% of whom were laboratory-confirmed influenza cases, and most of the confirmed cases (30.1%) were detected in February. In the 15?29 years age group, the type A influenza (H3N2) was more frequent among patients with ILI (54.9% vs. 34.2%, p = 0.040), and less frequent in patients with SARI (39.4% vs. 65.8%, p = 0.009) compared with influenza type B. In patients aged 30?64 years with ARDS, influenza type B was more common than influenza type A (H3N2) (13.4% vs. 6.2%, p = 0.032), but less common in compared to influenza type A (H1N1) pdm09 (13.4% vs. 25.7%, p = 0.017). The SARI case definition of influenza was associated with an increased likelihood of laboratoryconfirmed influenza for all age groups (p < 0.05). During the epidemic period, it was observed that the ILI case definition had the highest diagnostic value for influenza in the age group 5?14 (AUC = 0.733; 95% CI: 0.704?0.764), while the SARI and ARDS case definitions were the best predictors of influenza for patients 15?29 years of age (AUC = 0.565; 95% CI: 0.504?0.615 and AUC = 0.708; 95% CI: 0.489?0.708, respectively). The case definition of ARDS had the maximum sensitivity (100%) among patients 15?29 years of age. Conclusion. The proposed case definitions of influenza appeared to be good predictors of influenza and therefore can be useful for influenza surveillance, especially in the countries with limited laboratory capacities.

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