scholarly journals Preparing for a COVID-19 pandemic: a review of outbreak response measures from Australia perspective

2020 ◽  
Vol 3 (3) ◽  
Author(s):  
Rama Jayaraj ◽  
Chellan Kumarasamy ◽  
Ravishankar Ram M ◽  
Gothandam KM ◽  
Devi A ◽  
...  
Keyword(s):  
Outbreak Response ◽  
Response Measures

scholarly journals Transmissibility of coronavirus disease 2019 (COVID-19) in Chinese cities with different transmission dynamics of imported cases

2020 ◽  
Author(s):  
Ka Chun Chong ◽  
Wei Cheng ◽  
Shi Zhao ◽  
Feng Ling ◽  
Kirran N. Mohammad ◽  
...  
Keyword(s):  
Reproduction Number ◽  
Likelihood Function ◽  
Transmission Dynamics ◽  
Time Varying ◽  
Outbreak Response ◽  
Chinese Cities ◽  
Imported Cases ◽  
Response Measures ◽  
Local Transmission

AbstractBackgroundMonitoring the time-varying reproduction number (Rt) of the disease is useful in determining whether there is sustained transmission in a population. In this study, we examined Rt of COVID-19 and compared its transmissibility between different intervention periods in Hangzhou and Shenzhen.MethodsDaily aggregated counts of confirmed imported and local cases between January 1, 2020 and March 13, 2020 were analysed. A likelihood function was constructed to estimate Rt, accounting for imported cases.ResultsAlthough Hangzhou had fewer number of cases than Shenzhen, Shenzhen had higher proportion of imported cases than Hangzhou (83% vs 29%). Since the epidemic of COVID-19 in Shenzhen was dominated by imported cases, Rt was kept below unity through time. On the contrary, Rt was greater than unity in Hangzhou from 16 January to 7 February due to the surge in local cases. Credits to the Wuhan lockdown and outbreak response measures following the local lockdown, Rt decreased steadily and dropped below unity in mid-February.ConclusionThe lockdown measures and local outbreak responses helped reduce the potential of local transmission in Hangzhou and Shenzhen. Meanwhile, cities with similar epidemic trend could have different transmission dynamics given the variation in imported cases.

scholarly journals Transmissibility of coronavirus disease 2019 in Chinese cities with different dynamics of imported cases

PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e10350 ◽  
Author(s):  
Ka Chun Chong ◽  
Wei Cheng ◽  
Shi Zhao ◽  
Feng Ling ◽  
Kirran N. Mohammad ◽  
...  
Keyword(s):  
Reproduction Number ◽  
Transmission Dynamics ◽  
Outbreak Response ◽  
Chinese Cities ◽  
Before And After ◽  
Imported Cases ◽  
Response Measures ◽  
The City ◽  
Local Transmission

Background Monitoring the reproduction number (Rt) of the disease could help determine whether there is sustained transmission in a population, but areas with similar epidemic trends could have different transmission dynamics given the risk from imported cases varied across regions. In this study, we examined the Rt of coronavirus disease 2019 (COVID-19) by taking different dynamics of imported cases into account and compared the transmissibility of COVID-19 at different intervention periods in Hangzhou and Shenzhen. Methods We obtained the daily aggregated counts of laboratory-confirmed imported and local cases of COVID-19 infections in Hangzhou and Shenzhen from January 1 to March 13, 2020. Daily Rt and piecewise Rt before and after Wuhan lockdown were estimated, accounting for imported cases. Results Since the epidemic of COVID-19 in Shenzhen was dominated by imported cases, Rt was around 0.1 to 0.7 before the Wuhan lockdown. After the lockdown of Wuhan and the initialization of measures in response to the outbreak, local transmission was well-controlled as indicated by a low estimated value of piecewise Rt, 0.15 (95% CI [0.09–0.21]). On the contrary, Rt obtained for Hangzhou ranged from 1.2 to 4.9 with a piecewise Rt of 2.55 (95% CI [2.13–2.97]) before the lockdown of Wuhan due to the surge in local cases. Because of the Wuhan lockdown and other outbreak response measures, Rt dropped below unity in mid-February. Conclusions Even though Shenzhen had more cases than Hangzhou, local transmission did not sustain probably due to limited transmission from imported cases owing to the reduction in local susceptibles as residents left the city during Chunyun. The lockdown measures and local outbreak responses helped reduce the local transmissibility.

scholarly journals Gastroenteritis outbreaks on cruise ships: contributing factors and thresholds for early outbreak detection

2017 ◽  
Vol 22 (45) ◽  
Author(s):  
Varvara A Mouchtouri ◽  
Eleni Verykouki ◽  
Dumitru Zamfir ◽  
Christos Hadjipetris ◽  
Hannah C Lewis ◽  
...  
Keyword(s):  
Attack Rate ◽  
Outbreak Detection ◽  
Contributing Factors ◽  
Outbreak Response ◽  
Dose Response Relationship ◽  
Outbreak Management ◽  
Cruise Ships ◽  
Health Authorities ◽  
Management Plans ◽  
Response Measures

When an increased number of acute gastroenteritis (AG) cases is detected among tourists staying at the same accommodation, outbreak management plans must be activated in a timely manner to prevent large outbreaks. Syndromic surveillance data collected between 1 January 2010 and 31 December 2013 by five seagoing cruise ships were analysed to identify attack rate thresholds for early outbreak detection. The overall incidence rate of AG was 2.81 cases per 10,000 traveller-days (95% confidence interval (CI): 0.00–17.60), while the attack rate was 19.37 cases per 10,000 travellers (95% CI: 0.00–127.69). The probability of an outbreak occurring was 11% if 4 per 1,000 passengers reported symptoms within the first 2 days of the voyage, and this increased to 23 % if 5 per 1,000 passengers reported such within the first 3 days. The risk ratio (RR) for outbreak occurrence was 2.35, 5.66 and 8.63 for 1, 2 and 3 days’ delay of symptoms reporting respectively, suggesting a dose–response relationship. Shipping companies’ policies and health authorities’ efforts may consider these thresholds for initiating outbreak response measures based on the number of cases according to day of cruise. Efforts should focus on ensuring travellers report symptoms immediately and comply with isolation measures.

OPTIMISATION OF SAND CASTING PROCESS FOR IMPELLER USING TAGUCHI METHODOLOGY

2020 ◽  
Vol XVII (2) ◽  
pp. 23-33
Author(s):  
Faisal Hafeez ◽  
Salman Hussain ◽  
Wasim Ahmad ◽  
Mirza Jahanzaib
Keyword(s):  
Surface Roughness ◽  
Surface Defects ◽  
A356 Alloy ◽  
Casting Process ◽  
Sand Casting ◽  
Gate Length ◽  
Taguchi Methodology ◽  
Confirmatory Tests ◽  
Binder Ratio ◽  
Response Measures

This paper presents the study to investigate the effects of binder ratio, in-gate length and pouring height on hardness, surface roughness and casting defects of sand casting process. Taguchi methodology with L9 orthogonal array was employed to design the experimentation. Sand casting of six blade impeller using A356 alloy was performed and empirical models for all the above response measures were formulated. Confirmatory tests and analysis of variance results confirmed the accuracy of the model. Binder ratio was found to be the most significant parameter affecting casting surface defects and surface roughness. This was followed by pouring height and in-gate length.

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