• Journal of Preventive Medicine and Public Health
• /
• v.53 no.5
• /
• pp.307-310
• /
• 2020

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has placed unprecedented pressure on healthcare systems, even in advanced economies. While the number of cases of SARS-CoV-2 in Africa compared to other continents has so far been low, there are concerns about under-reporting, inadequate diagnostic tools, and insufficient treatment facilities. Moreover, proactiveness on the part of African governments has been under scrutiny. For instance, issues have emerged regarding the responsiveness of African countries in closing international borders to limit trans-continental transmission of the virus. Overdependence on imported products and outsourced services could have contributed to African governments' hesitation to shut down international air and seaports. In this era of emerging and re-emerging pathogens, we recommend that African nations should consider self-sufficiency in the health sector as an urgent priority, as this will not be the last outbreak to occur. In addition to the Regional Disease Surveillance Systems Enhancement fund (US$600 million) provided by the World Bank for strengthening health systems and disease surveillance, each country should further establish an epidemic emergency fund for epidemic preparedness and response. We also recommend that epidemic surveillance units should create a secure database of previous and ongoing pandemics in terms of aetiology, spread, and treatment, as well as financial management records. Strategic collection and analysis of data should also be a central focus of these units to facilitate studies of disease trends and to estimate the scale of requirements in preparation and response to any future pandemic or epidemic.

• Journal of Digital Convergence
• /
• v.16 no.7
• /
• pp.259-265
• /
• 2018

Compartment models, a type of mathematical model, have been widely applied to characterize the changes in a dynamic system with sequential events or processes, such as the spread of an epidemic disease. A compartment model comprises compartments, and the relations between compartments are depicted as boxes and arrows. This principle is similar to that of the system dynamics (SD) approach to constructing a simulation model with stocks and flows. In addition, both models are structured using differential equations. With this mutual and translatable principle, this study, in terms of SD, translates a reference SEIR model, which was developed in a recent study to characterize the transmission of the Middle East respiratory syndrome (MERS) in South Korea. Compared to the replicated result of the reference SEIR model (Model 1), the translated SEIR model (Model 2) demonstrates the same simulation result (error=0). The results of this study provide insight into the application of SD relative to constructing an epidemic compartment model using schematization and differential equations. The translated SD artifact can be used as a reference model for other epidemic diseases.

• Journal of applied mathematics & informatics
• /
• v.27 no.3_4
• /
• pp.779-793
• /
• 2009

This paper deals with a delayed SEIRS epidemic model with pulse vaccination and crowded incidence rate. Moreover, the case of vertical and horizontal transmission is considered. By using the discrete dynamical system determined by the stroboscopic map, the exact infection-free periodic solution of the SEIRS model is obtained. Further, by employing the comparison arguments, we prove that under the condition that $R_*$ < 1 the infection-free periodic solution is globally attractive, and that under the condition that $R^*$ > 1 the disease is uniformly persistent, which means that after some period of time the disease will become endemic.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.24 no.1
• /
• pp.1-10
• /
• 1979

In order to investigate the causes of epidemic out break of rice blast disease in 1978, investigations were undertaken in respect of climatic conditions, variety, cultural practice and plant pathology. During 1978, especially in August at heading time, it was higher temperature and humidity, higher frequency and amount of rainfall, lower amount of sunshine and solar radiation than less blast infested years. Nitrogen content in rice plant was higher than previous years. Acreage increase of semi-dwarf varieties brought about a result of proportional increase of new blast races which are able to infect the semi-dwarf varieties. It was concluded that those conditions mentioned above might have caused the result of severe neck blast disease in rice varieties in Korea, 1978.

• Journal of the Korean Mathematical Society
• /
• v.58 no.1
• /
• pp.45-67
• /
• 2021

In this paper, a mathematical dynamical system involving both deterministic (with or without delay) and stochastic "SIR" epidemic model with nonlinear incidence rate in a continuous reactor is considered. A profound qualitative analysis is given. It is proved that, for both deterministic models, if ��d > 1, then the endemic equilibrium is globally asymptotically stable. However, if ��d ≤ 1, then the disease-free equilibrium is globally asymptotically stable. Concerning the stochastic model, the Feller's test combined with the canonical probability method were used in order to conclude on the long-time dynamics of the stochastic model. The results improve and extend the results obtained for the deterministic model in its both forms. It is proved that if ��s > 1, the disease is stochastically permanent with full probability. However, if ��s ≤ 1, then the disease dies out with full probability. Finally, some numerical tests are done in order to validate the obtained results.

• Research in Plant Disease
• /
• v.10 no.2
• /
• pp.121-125
• /
• 2004

An epidemic of target leaf spot of cucumber (Cucumis sativus) occurred in commercial greenhouses in Korea in 2000/2001. The early symptoms on the leaves were small brown spots with yellow halos. These lesions became irregular enlarging in diameter and eventually defoliation resulted. The causal agent was a fungus with morphological characteristics matching Corynespora cassiicola. The sequence of the ITS region of C. cassiicola CM2000-1 was identical to that of an authentic strain of Corynespora cassiicola. Optimal germination of spores and mycelial growth on plate was at 3$0^{\circ}C$. A long dew period on the leaf surface and high temperatures were the main contributing factors for disease development and the greenhouse epidemic. Artificial inoculation of the Korean isolate of C. cassiicola revealed resistance in some Korean cucumber cultivars.

• Journal of the Korean Data and Information Science Society
• /
• v.26 no.2
• /
• pp.301-312
• /
• 2015

The purpose of this paper is to establish the epidemic model to explain the process of disease spread. The process of disease spread can be classified into two types: deterministic process and stochastic process. Most studies supposed that the process follows the deterministic process and established the model using the ordinary differential equation. In this article, we try to build the disease spread prediction model based on the SIR (Suspectible - Infectious - Recovered) model. we first estimated the model parameters using least squared method and applied to a deterministic model using ordinary differential equation. we also applied to a stochastic model based on Gillespie algorithm. The methods introduced in this paper are applied to the data on the number of cases of malaria every week from January 2001 to March 2003, released by Korea Centers for Disease Control and Prevention. As a result, we conclude that our model explains well the process of disease spread.

• Journal of Korean Medical classics
• /
• v.30 no.4
• /
• pp.83-93
• /
• 2017

Objective : Doctors' discussions on Makwon's warm-disease are studied in an effort to contemplate a way to use the outcome in practice. Method : Doctors' discussions on Makwon as found in researches and texts are categorized into physical and pathologica, and their symptoms and treatments are analyzed. Result & Conclusion : Many doctors of warm disease explained that, in terms of the physical aspect, Makwon is closely related to stomach. Some doctors also mentioned its relationship with triple engizers, defense and nutrient qi, and spleen. In terms of pathology, most of the doctors considered Makwon to be a hiding place of foul turbidity pathogen, and explained that a treatment has to be applied before the disease pattern worsens. Diverse syndroms of Makwonwere introduced. Their discussions mainly revolved around warm and epidemic or category of dampness-heat diseases. Alternating chills and fever was also mentioned often, and generalized pain, nausea, tongue of thick and slimy fur symptoms are shown. Ouguk's Dalwonneum is used as the basic treatment. The most effective prevention method of the incubation of pathogen are the symptoms that allows the analysis of the mechanism of disease. Therefore, a good utilization method of resolve turbidity with aroma or spices may contribute to the prevention of Makwon-disease in terms of cultural aspect.

• Journal of Preventive Medicine and Public Health
• /
• v.53 no.2
• /
• pp.65-66
• /
• 2020

• The Journal of Korean Medical History
• /
• v.33 no.1
• /
• pp.11-20
• /
• 2020

The Office for Saving Lives (活人署) (OSL) was the office in charge of the treatment and relief of the poor in the Joseon Dynasty. This study disputes prior scholarship on the OSL by analyzing the use of a ready-made prescription and by focusing on the personality of the OSL's medical institutions. The work of the three government offices, the Office of Great Mercy (大悲院) (OGM), which was the formal office of OSL, the Office of Benefiting People (惠民署) and the Office of Aiding Life (濟生院), overlapped in the area of relief of the common people. But OGM was different from the other two in that it was not a purely medical office, had no educational function, and did not manage medicine. By analyzing a standing prescription, this article argues: 1) Heojun's influence on the composition of a standing prescription is absolute. 2) Epidemic warm disease (溫疫) was a major social problem in terms of emergency medical care at the time. 3) In the late Joseon Dynasty, the treatment of epidemic warm diseases became more sophisticated than the previous era.