ABSTRACT
Objective To investigate the prevalence and influencing factors of Blastocystis hominis infection among children with diarrhea under five years of age in Guangzhou City. Methods Children with diarrhea under 5 years of age admitted to Guangzhou Children’s hospital, Guangzhou Maternity and Child Healthcare Hospital and Guangzhou Women and Children’s Medical Center during the period between January 1 and December 31, 2020, were enrolled. Participants’ demographics, living environments and health status were collected using questionnaire surveys. Stool samples were collected from participants and nucleic acid was extracted. B. hominis infection was identified using PCR assay and sequence alignment, and the factors affecting B. hominis infection among children with diarrhea under 5 years of age were identified using univariate analysis and multivariate logistic regression analysis. Results A total of 684 children with diarrhea under 5 years of age were enrolled, including 468 male children and 216 female children, with a mean age of (1.79 ± 1.12) years. The overall prevalence of B. hominis infection was 4.97% [34/684, 95% confidential interval (CI): (3.59%, 6.86%)] among participants, and there was no significant difference in the prevalence of B. hominis infection between children with chronic [7.52% (20/266), 95% CI: (4.92%, 11.33%)] and acute diarrhea [3.35% (14/418), 95% CI: (2.01%, 5.54%)] (χ2 = 5.983, P = 0.014). Multivariate logistic regression analysis identified keeping pet [odds ratio (OR) = 6.298, 95% CI: (2.711, 14.633)], drinking non-tap water [OR = 4.522, 95% CI: (1.769, 11.561)], lactose intolerance [OR = 4.221, 95% CI: (1.043, 17.087)], antibiotic use [OR = 0.125, 95% CI: (0.017, 0.944)] and chronic diarrhea [OR = 2.172, 95% CI: (1.018, 4.637)] as factors affecting B. hominis infection among children with diarrhea under 5 years of age in Guangzhou City. Conclusions B. hominis infections is detected in children with diarrhea under five years of age in Guangzhou City. Improving home environments and pet-keeping hygiene is recommended to reduce the likelihood of B. hominis infection among children.
ABSTRACT
Objective To create a model based on meteorological data to predict the regions at risk of schistosomiasis during the flood season, so as to provide insights into the surveillance and forecast of schistosomiasis. Methods An interactive schistosomiasis forecast system was created using the open-access R software. The schistosomiasis risk index was used as a basic parameter, and the species distribution model of Oncomelania hupensis snails was generated according to the cumulative rainfall and temperature to predict the probability of O. hupensis snail distribution, so as to identify the regions at risk of schistosomiasis transmission during the flood season. Results The framework of the web page was built using the Shiny package in the R program, and an interactive and visualization system was successfully created to predict the distribution of O. hupensis snails, containing O. hupensis snail surveillance site database, meteorological and environmental data. In this system, the snail distribution area may be displayed and the regions at risk of schistosomiasis transmission may be predicted using the species distribution model. This predictive system may rapidly generate the schistosomiasis transmission risk map, which is simple and easy to perform. In addition, the regions at risk of schistosomiasis transmission were predicted to be concentrated in the middle and lower reaches of the Yangtze River during the flood period. Conclusions A schistosomiasis forecast system is successfully created, which is accurate and rapid to utilize meteorological data to predict the regions at risk of schistosomiasis transmission during the flood period.
ABSTRACT
This paper aims to find out the impacts of meteorological factors on malaria transmission by exploring the relationship between monthly local malaria cases and meteorological factors in Tengchong county,so as to develop malaria control strategy.Plasmodium vivax malaria incidence data and meteorological data including monthly mean temperature,maximum temperature,minimum temperature,rainfall,relative humidity,and minimum humidity in Tengchong County,Yunnan from 2005 to 2010 were provided by the Chinese Center for Disease Control and China Meteorological Administration.The correlation between malaria incidence and meteorological factors was analyzed using Pearson correlation analysis.The generalized additive model (GAM) was applied to investigate the relationship between monthly local malaria cases and meteorological factors.Results showed that there was a weak positive correlation between minimum temperature,mean relative humidity as well as minimum relative humidity and local malaria incidences.While a complex nonlinear relationship between the vectorial capacity,relative humidity and the incidence of malaria was detected.Malaria transmission increases when the vectorial capacity was greater than 10 (VCAP＞10) or the average relative humidity was between 55％ and 70％.The malaria transmission declines when relative humidity above 70％.The relationship between meteorological factors and the incidence of local malaria is well explained by GAM,and there is a complex nonlinear relationship between vectorial capacity,relative humidity and malaria incidence.