Spatiotemporal Patterns of Japanese Encephalitis in China, 2002–2010

Abstract

ObjectiveThe aim of the study is to examine the spatiotemporal pattern of Japanese Encephalitis (JE) in mainland China during 2002–2010. Specific objectives of the study were to quantify the temporal variation in incidence of JE cases, to determine if clustering of JE cases exists, to detect high risk spatiotemporal clusters of JE cases and to provide evidence-based preventive suggestions to relevant stakeholders.MethodsMonthly JE cases at the county level in mainland China during 2002–2010 were obtained from the China Information System for Diseases Control and Prevention (CISDCP). For the purpose of the analysis, JE case counts for nine years were aggregated into four temporal periods (2002; 2003–2005; 2006; and 2007–2010). Local Indicators of Spatial Association and spatial scan statistics were performed to detect and evaluate local high risk space-time clusters.ResultsJE incidence showed a decreasing trend from 2002 to 2005 but peaked in 2006, then fluctuated over the study period. Spatial cluster analysis detected high value clusters, mainly located in Southwestern China. Similarly, we identified a primary spatiotemporal cluster of JE in Southwestern China between July and August, with the geographical range of JE transmission increasing over the past years.ConclusionJE in China is geographically clustered and its spatial extent dynamically changed during the last nine years in mainland China. This indicates that risk factors for JE infection are likely to be spatially heterogeneous. The results may assist national and local health authorities in the development/refinement of a better preventive strategy and increase the effectiveness of public health interventions against JE transmission.

Using the Kulldorff’s scan statistical analysis to detect spatio-temporal clusters of tuberculosis in Qinghai Province, China, 2009–2016

“…The most likely spatio-temporal cluster area was located at the southwest of the province, and the high-risk period was from September 2014 to December 2016 (LLR = 2547.64, P < 0.001). The center of this area was in Yushu County, 32.91°N and 96.68°E, which was a circular area with a radius of 261.34 km, covering seven counties: Yushu, Nangqian, Chengduo, Zaduo, Maduo, Qumalai, and Dari. A total of 3916 TB cases were reported in this area during the high-risk period, and the RR was 4.21 (Table 4).…”

How environmental conditions impact mosquito ecology and Japanese encephalitis: An eco-epidemiological approach

“…All cases are diagnosed according to the China National diagnostic criteria for Japanese encephalitis (Ministry of Health, 2006) that an individual who lived in an epidemic area during the vector-biting season or traveled to an epidemic area within 25 days prior to illness onset, with one of these following laboratory criteria for diagnosis: presence of JEV-specific IgM antibody in a single sample of cerebrospinal fluid or serum by using the enzyme-linked immunosorbent assay (MAC ELISA) with a JEV IgM-capture ELISA kit (Shanghai B&C Biological Technology Co., Ltd., Shanghai, China) as described in published articles (Ye et al, 2010), JE virus antigens, a 4-fold rise in JE virus-specific antibody, JE virus genome in samples by PCR, or isolated JE virus (Wang et al, 2013).…”

The potential impact of climate change and ultraviolet radiation on vaccine-preventable infectious diseases and immunization service delivery system

“…The effect of vaccination against vaccine-preventable diseases can only be assessed properly, after controlling for climate variability [44] and nonclimatic confounding factors such as socio-demographic and economic changes in the analytical models [98]. However, this review found that the effect of non-climatic factors has been neglected by most studies; only a few studies included nonclimatic factors.…”