Time series analysis of cumulative incidences of typhoid and paratyphoid fevers in China using both Grey and SARIMA models.

Jiaqi Gao,Jiayuan Li,Mengqiao Wang,Ka Chun Chong

doi:10.1371/journal.pone.0241217

Jiaqi Gao, Jiayuan Li + Show 2 more

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https://doi.org/10.1371/journal.pone.0241217

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Journal: PloS one	Publication Date: Oct 28, 2020
Citations: 10	License type: CC BY 4.0

Affiliation: West China Medical Center of Sichuan University

Abstract

Typhoid and paratyphoid fevers are common enteric diseases causing disability and death in China. Incidence data of typhoid and paratyphoid between 2004 and 2016 in China were analyzed descriptively to explore the epidemiological features such as age-specific and geographical distribution. Cumulative incidence of both fevers displayed significant decrease nationally, displaying a drop of 73.9% for typhoid and 86.6% for paratyphoid in 2016 compared to 2004. Cumulative incidence fell in all age subgroups and the 0–4 years-old children were the most susceptible ones in recent years. A cluster of three southwestern provinces (Yunnan, Guizhou, and Guangxi) were the top high-incidence regions. Grey model GM (1,1) and seasonal autoregressive integrated moving average (SARIMA) model were employed to extract the long-term trends of the diseases. Annual cumulative incidence for typhoid and paratyphoid were formulated by GM (1,1) as and respectively. SARIMA (0,1,7) × (1,0,1)12 was selected among a collection of constructed models for high R2 and low errors. The predictive models for both fevers forecasted cumulative incidence to continue the slightly downward trend and maintain the cyclical seasonality in near future years. Such data-driven insights are informative and actionable for the prevention and control of typhoid and paratyphoid fevers as serious infectious diseases.

Highlights

Typhoid and paratyphoid fevers, collectively referred to as enteric fever, are caused by systematic infection with the gram-negative bacterium Salmonella enterica serotype S. typhi and S. paratyphi [1]
This study aims to conduct a thorough analysis of the long-term cumulative incidence of both typhoid and paratyphoid fevers in China at both national and regional levels, at both yearly and seasonal windows, and on the susceptibility of people of various ages
Incidence counts displayed a significant trend of decrease: almost 33000 cases of typhoid fever was reported in 2004 but the count fell below 10000 and stayed in the close range since 2010; more than 16000 cases of paratyphoid fever was reported in 2004, and the continual downfall reached to 2311 cases in 2016 (Fig 1A)

Summary

Introduction

Collectively referred to as enteric fever, are caused by systematic infection with the gram-negative bacterium Salmonella enterica serotype S. typhi and S. paratyphi (types of A, B, and C) [1]. The organisms enter the patients via the gastrointestinal tract and get into the bloodstream via the lymphatic channels, and a mouse model has been engineered [2]. Sanitary measures and personal hygiene play instrumental role as infections generally occur after intaking food or water contaminated by urine or feces [3]. The incubation period could generally last from 3 to 42 days, with on average 14 days for typhoid and 2–15 days for paratyphoid [4]. Clinical manifestations include high-temperature fever, prostration, fatigue, headache, and gastrointestinal reactions, with serious complications such as intestinal.

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