| JaLCDOI | 10.18926/AMO/45268 |
|---|---|
| FullText URL | 65_2_97.pdf |
| Author | Tsuchihashi, Yuuki| Yorifuji, Takashi| Takao, Soshi| Suzuki, Etsuji| Mori, Shigeru| Doi, Hiroyuki| Tsuda, Toshihide| |
| Abstract | Seasonal influenza infection is a major challenge in public health. The term "seasonal influenza" refers to the typical increase in the number of influenza patients in the winter season in temperature zones. However, it is not clear how environmental factors within a single flu season affect influenza infection in a human population. Therefore, we evaluated the effects of temperature and humidity in the 2006-7 flu season on the onset of seasonal influenza using a case-crossover study. We targeted patients who attended one pediatric clinic in Okayama city, Japan and who were diagnosed as being infected with the seasonal influenza virus. Using 2 references (time-stratified and symmetric bidirectional design), we estimated the effects of average temperature and relative humidity from the onset day (lag0) to 10 days before (lag10). The total number of subjects was 419, and their onset days ranged from 26 December 2006 to 30 April 2007. While the onset was significantly associated with lower temperature, relative humidity was not related. In particular, temperatures before the 3-day incubation period had higher-magnitude odds ratios. For example, the odds ratio and 95% confidence interval for average temperature at time lag 8 was 1.12 (1.08-1.17) per 1.0℃ decrease. Low environmental temperature significantly increased the risk of seasonal influenza onset within the 2006-7 winter season. |
| Keywords | seasonal influenza in humans temperature humidity case-crossover study |
| Amo Type | Original Article |
| Publication Title | Acta Medica Okayama |
| Published Date | 2011-04 |
| Volume | volume65 |
| Issue | issue2 |
| Publisher | Okayama University Medical School |
| Start Page | 97 |
| End Page | 103 |
| ISSN | 0386-300X |
| NCID | AA00508441 |
| Content Type | Journal Article |
| language | English |
| Copyright Holders | CopyrightⒸ 2011 by Okayama University Medical School |
| File Version | publisher |
| Refereed | True |
| PubMed ID | 21519367 |
| Web of Science KeyUT | 000289818800005 |
| JaLCDOI | 10.18926/AMO/45264 |
|---|---|
| FullText URL | 65_2_63.pdf |
| Author | Mizoguchi, Yoshinori| Suzuki, Etsuji| Tsuchida, Hiroaki| Tsuda, Toshihide| Yamamoto, Eiji| Nakase, Katsumi| Doi, Hiroyuki| |
| Abstract | There have been only 2 reports of a large-scale foodborne outbreak arising from Salmonella enterica serotype Braenderup infection worldwide. On August 9, 2008, an outbreak originating in boxed lunches occurred in Okayama, Japan. We conducted a cohort study of 786 people who received boxed lunches from a particular catering company and collected 644 questionnaires (response rate:82%). Cases were defined as those presenting with diarrhea (≧4 times in 24h) or fever (≧38℃) between 12 am on August 8 and 12 am on August 14. We identified 176 cases (women/men:39/137);younger children (aged＜10 years) appeared to more frequently suffer severe symptoms. Three food items were significantly associated with higher risk of illness;tamagotoji (soft egg with mixed vegetables and meat) (relative risk (RR):11.74, 95% confidence interval (CI):2.98-46.24), pork cooked in soy sauce (RR:3.17, 95% CI:1.24-8.10), and vinegared food (RR:4.13, 95% CI:1.60-10.63). Among them, only the RR of tamagotoji was higher when we employed a stricter case definition. Salmonella Braenderup was isolated from 5 of 9 sampled cases and 6 food handlers. It is likely that unpasteurized liquid eggs contaminated by Salmonella Braenderup and used in tamagotoji caused this outbreak. |
| Keywords | boxed lunch cohort study foodborne diseases Salmonella Braenderup unpasteurized liquid eggs |
| Amo Type | Original Article |
| Publication Title | Acta Medica Okayama |
| Published Date | 2011-04 |
| Volume | volume65 |
| Issue | issue2 |
| Publisher | Okayama University Medical School |
| Start Page | 63 |
| End Page | 69 |
| ISSN | 0386-300X |
| NCID | AA00508441 |
| Content Type | Journal Article |
| language | English |
| Copyright Holders | CopyrightⒸ 2011 by Okayama University Medical School |
| File Version | publisher |
| Refereed | True |
| PubMed ID | 21519363 |
| Web of Science KeyUT | 000289818800001 |
