How the H1N1 influenza epidemic spread among university students in Japan: Experience from Shinshu University

Background: A worldwide outbreak of influenza A/H1N1 occurred in 2009. Little information is available regarding how the epidemic spread among young people, who composed the majority of individuals infected with this virus. We assessed the route of transmission of H1N1 among university students at Shinshu University, Japan. Methods: A total of 11,424 students were monitored between August 2009 and March 2010, and those who were diagnosed with confirmed, probable, or suspected H1N1 at a hospital or clinic were registered based on self-report to the university. Data including date of onset and suspected infection route were collected from the affected patients. Results: Of the 11,424 students, 1,016 (8.9%) were infected with H1N1. In most infected students, the suspected transmission route was associated with club activity, followed by close contact with friends and through lectures or laboratory work. After suspension of activity by clubs with more than 2 infected members, the number of infected individuals decreased. Conclusion: H1N1 influenza spread in the university through specific routes, including club activity, close contact with friends, and lectures or laboratory work. During future outbreaks of influenza, interventions to reduce transmission through these routes may be effective infection control strategies in university students.ArticleAMERICAN JOURNAL OF INFECTION CONTROL. 40(3):218-220 (2012)journal articl

Effects of weather variability and air pollutants on emergency admissions for cardiovascular and cerebrovascular diseases.

This is an Author's Original Manuscript of an Article submitted for consideration in the International journal of environmental health research copyright (c) 2012 Taylor & Francis; International journal of environmental health research is available online at http://www.tandfonline.com/10.1080/09603123.2011.650155信州大学博士（医学）・学位論文・平成23年3月31日授与（甲第901号）・掘綾We examined the effect of ambient temperature, air pressure and air pollutants on daily emergency admissions by identifying the cause of admission for each type of stroke and cardiovascular disease using generalized linear Poisson regressionmodels allowing for overdispersion, and controlling for seasonal and inter-annual variations, days of the week and public holidays, levels of influenza and respiratory syncytial viruses. Every 1 degrees C decrease in mean temperature was associated with an increase in the daily number of emergency admissions by 7.83% (95% CI 2.06-13.25) for acute coronary syndrome (ACS) and heart failure, by 35.57% (95% CI 15.59-59.02) for intracerebral haemorrhage (ICH) and by 11.71% (95% CI 4.1-19.89) for cerebral infarction. An increase of emergency admissions due to ICH (3.25% (95% CI 0.94-5.51)), heart failure (3.56% (95% CI 1.09-5.96)) was observed at every 1 hPa decrease in air pressure from the previous days. We found stronger detrimental effect of cold on stroke than cardiovascular disease.Articlejournal articl

Evaluation of factors affecting variations in influenza A/H1N1 history in university students, Japan

Although the natural history of H1N1 has been found to vary among patients, little is known about the factors that affect these variations. Infected patients with an extended infection history may shed virus longer and spread infection. To further clarify these variations, we evaluated the natural history of H1N1 infection in 324 university students using a descriptive epidemiological method and analyzed factors affecting the natural history of infection. The median times from infection to fever development and from fever development to cure were 2 days (range 0?8 days) and 5 days (range 1?12 days), respectively, and the median time not attending classes was 5 days (range, 1?13 days). Variations in H1N1 natural history were associated with both environmental and individual factors, including route of infection, grade, gender, epidemic period, respiratory and gastrointestinal symptoms and headache. Steps affecting these factors may help control variations in H1N1 natural history and may enhance infection control measures.ArticleJOURNAL OF INFECTION AND CHEMOTHERAPY. 19(4):665-672 (2013)journal articl

Evaluation of the spread of pandemic influenza A/H1N1 2009 among Japanese university students

online first / Published online: 4 July 2014The pandemic influenza A/H1N1 2009 virus is commonly known to affect younger individuals. Several epidemiological studies have clarified the epidemic features of university students in Japan. In this study, we reviewed these studies in Japan in comparison with reports from other countries. The average cumulative incidence rate among university students was 9.6 %, with the major symptoms being cough, sore throat, and rhinorrhea. These epidemiological features were similar between Japan and other countries. Attitudes and behaviors toward pandemic influenza control measures were different before and improved during and after the epidemic. These features were also similar to those in other countries. On the other hand, the epidemic spread through club activities or social events, and transmission was attenuated after temporary closure of such groups in Japan. This transmission pattern was inconsistent among countries, which may have been due to differences in lifestyle and cultural habits. Based on these results, infection control measures of pandemic influenza for university organizations in Japan should be considered.ArticleEnvironmental Health and Preventive Medicine. 19(5):315-321 (2014)journal articl

A novel device (SD-101) with high accuracy for screening sleep apnoea-hypopnoea syndrome

Background and objective: The SD-101 is a non-restrictive, sheet-like medical device with an array of pressure sensors, to detect sleep-disordered breathing by sensing gravitational alterations in the body corresponding to respiratory movements. This study evaluated the accuracy of the SD-101 for screening sleep apnoea-hypopnoea syndrome (SAHS) by comparison with polysomnography. Methods: Nocturnal polysomnography and SD-101 monitoring were conducted simultaneously and compared in 201 patients with suspected SAHS (suspected SAHS group) and 165 male employees of a transport company (screening group). Results: Polysomnography revealed an AHI of = 60 events/h in 39, 35, 38, 68 and 21 subjects in the suspected SAHS group and 103, 34, 12, 12 and four subjects in the screening group, respectively. Central SAHS and obstructive SAHS were subsequently diagnosed in 11 (5.5%) and 135 (67.2%) of subjects in the suspected SAHS group and five (3.0%) and 39 (23.6%) of subjects in the screening group, respectively. Significant correlations were apparent between AHI and the respiratory disturbance index (RDI) measured with the SD-101 in both the suspected SAHS group (r = 0.88) and screening group (r = 0.92). Receiver operating characteristic curve analysis revealed 89.5% sensitivity and 85.8% specificity in identifying SAHS, using an RDI of 14.0 events/h. Conclusions: These findings suggest that the SD-101 is a useful device for screening SAHS.ArticleRESPIROLOGY. 14(8):1143-1150 (2009)journal articl

Adjuvant Chemotherapy with Gemcitabine for Resected Biliary Tract Cancer: A Single-Arm Phase 2 Study

Article信州医学雑誌 65(2): 99-111(2017)journal articl

Effect of Application of Subcutaneous Suction Drainage with Subcuticular Sutures for Wound Closure on the Incidence of Incisional Surgical Site Infection following Elective General Abdominal Surgery : A Randomized Controlled Trial

Article信州医学雑誌 63(2):91-101 (2015)journal articl

Consideration of alternative method to Durham pollen sampler method

目的：障害物や通行量があると設置しづらいダーラム型花粉捕集法に代わる方法として、ベランダ下にポリエチレンテレフタレート（PET）樹脂板をクリップで固定する重力法の有用性について検討を行った。方法：ダーラム型花粉捕集法（以下、ダーラム法）とクリップ捕集法（クリップ法）の差異を、スライドグラスを用いて比較した。また、割れにくく、扱い易いPET 樹脂板を使用可能か、ダーラム型花粉捕集法でスライドグラスとPET 樹脂板の捕集効率の差異を比較した。そして、PET 樹脂板を用いたクリップ法を、15 か所の保育園のベランダに2 器設置、比較し、同一地域内での花粉捕集量の差異を検討した。結果：3 か所でダーラム法とクリップ法を、それぞれ40 回測定し比較したところ、花粉数の相関係数は0.88 ～ 0.94（p<0.01）だった。クリップ法の花粉捕集総数はそれぞれダーラム法の1.38 ～ 1.59 倍であった。ダーラム法でスライドグラスとPET 樹脂板を比較した結果、相関係数0.99（p<0.01）で、後者の捕集数は前者の1.17 倍だった。同一地域内15 か所の保育園のベランダに設置したクリップ法2 器によりスギ花粉数を測定した結果、相関係数は0.90（p<0.01）で、保育園毎の差異は小さかった。考察：ダーラム型捕集器を設置しづらい施設において、PET 樹脂板を用いたクリップ捕集法は有用であると考えられた。We examined the validity of the gravity slide method for clipping PET plastic plates in verandas at facilities unsuitable for installing a Durham sampler due to the presence of obstacles and traffic.（ 1） Differences in the number of collections between the Durham and clip samplers were compared using glass slides. Pollen counts collected 40 times each under the porch and the eaves using clips were highly correlated with the counts using the Durham sampler. The correlation coefficients were 0.88 - 0.94（ p<0.01）. The total number of pollen collected using the clips was 1.38 - 1.59 times higher than that collected by the Durham sampler（. 2） Cedar pollen counts were collected 50 times with Durham samplers. The number collected by the PET plastic plates was 1.17 times higher than that by glass slides. The correlation coefficient was 0.99（ p<0.01）.（ 3） The number of cedar pollen collected using the PET plastic plates at two locations under the verandas of 15 nurseries over fifteen days was approximated for each nursery, with a correlation coefficient of 0.90（ p<0.01）. The gravity slide method using PET plastic plates in verandas may be useful at facilities unsuitable for installing a Durham sampler.journal articl