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Incubation ratio estimation for Plasmodium vivax malaria in Korea using truncated mixture model
Journal of the Korean Data & Information Science Society 2018;29:1025-35
Published online July 31, 2018
© 2018 Korean Data and Information Science Society.

Kwangyee Ko1 · Ilsu Choi2

12Department of Statistics, Chonnam National University, Korea
Correspondence to: Professor, Department of Statistics, Chonnam National University, Gwangju, 61186, Korea. E-mail:
Received June 19, 2018; Revised July 14, 2018; Accepted July 16, 2018.
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License ( which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
There are two types of incubation period for Plasmodium vivax malaria in Korea: long-term and short-term. In this study, considering the fact that the short-term latent phase of the illness of Plasmodium vivax malaria occurred after the warm-up of the airborne mosquito, which is the mediator of the Anopheles sinensis mosquito, we were assumed the frequency of patients with long-term latency to be normal distribution, and the frequency of patients with short-term latency to be truncated normal distribution. We estimated by the maximum-likelihood method using the EM algorithm using the mixed normal model. Estimated short-term and long-term rates were 71.3% in longterm latency period, which was different from previous studies. The estimated longterm latency probability distribution has a tendency to increase in the total mixed distribution. As the number of patients decreased, the proportion of patients with long-term latency increased.
Keywords : Anopheles sinensis, incubation ratio, Plasmodium vivax malaria, truncated mixture distribution.