Background: In 2021, the World Health Organization officially declared the People’s Republic of China as malaria-free. However, despite this milestone achievement, the continued occurrence of severe and fatal cases of imported malaria in China, due to globalization and increased international communication, remains a significant public health concern. Objective: The aim of this study was to elucidate the epidemiological characteristics of imported malaria in 5 Chinese provinces from 2014 to 2021 and to identify the factors that influence complications in imported malaria cases. The findings will provide a basis for enhancing prevention and control measures, thereby consolidating China’s achievements in malaria elimination. Methods: A case-based retrospective study was performed, using surveillance data collected from the representative provinces of China from 2014 to 2021. Epidemiological characteristics were analyzed using descriptive statistics. Logistic regression was used to identify the factors influencing the occurrence of complications. Results: A total of 5559 malaria cases were included during the study period. The predominant species was Plasmodium falciparum (3940/5559, 70.9%), followed by Plasmodium ovale (1054/5559, 19%), Plasmodium vivax (407/5559, 7.3%), Plasmodium malariae (157/5559, 2.8%), and 1 case of Plasmodium knowlesi. Most of the cases were male (5343/5559, 96.1%). The complication rates for P falciparum and P ovale were 11.4% and 3.3%, respectively. Multivariate logistic regression analysis of the relevant factors of malaria complications revealed potential protective factors, including a previous infection by Plasmodium (P<.001; odds ratio [OR] 0.512, 95% CI 0.422‐0.621), and risk factors, including increased age (P=.004; OR 1.014, 95% CI 1.004‐1.024), misdiagnosis at the first clinical visit (P<.001; OR 3.553, 95% CI 2.886‐4.375), and the time interval from onset to treatment (P=.001; OR 1.026, 95% CI 1.011‐1.042). Subgroup analyses identified risk factors associated with P falciparum, which include advanced age (P=.004; OR 1.015, 95% CI 1.005‐1.026), initial misdiagnosis during the first clinical visit (P<.001; OR 3.549, 95% CI 2.827‐4.455), the time interval from onset to treatment (P<.001; OR 1.043, 95% CI 1.022‐1.063), and a delay of more than 3 days from the first treatment to diagnosis (P<.001; OR 2.403, 95% CI 1.823‐3.164). Additionally, the risk factors pertaining to P ovale involve misdiagnosis at the initial clinical visit (P=.01; OR 2.901, 95% CI 1.336‐6.298), the time interval from onset to treatment (P=.002; OR 1.095, 95% CI 1.033‐1.160), and the duration from the initial treatment to diagnosis (P=.43; OR 1.032, 95% CI 0.953‐1.118). Previous infections can prevent the progression of both P falciparum and P ovale. Conclusions: This study showed that the increasing proportion of P ovale in recent years should not be ignored. Furthermore, there is a need to improve diagnostic awareness, enhance the capacity of medical institutions, and provide health education for high-risk groups.

Psittacosis caused by Chlamydia psittaci has re-emerged in China as sporadic cases and localized outbreaks. However, current knowledge remains fragmented across the clinical, veterinary, epidemiological, and public health fields. This scoping review mapped studies on psittacosis in China, identified major knowledge gaps, and defined priorities for research, clinical management, and prevention and control. Following the Arksey and O’Malley framework and Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR), China National Knowledge Infrastructure (CNKI), Wanfang, PubMed, Web of Science, and Embase were searched for studies published between 1 January 1985 and 31 December 2025 and synthesized eligible studies with descriptive statistics and thematic analysis. A total of 424 studies were included. Research interest showed recent sharp increases and was concentrated in Eastern and Central China. Case reports and series dominated the literature, whereas analytic epidemiology, standardized surveillance, and high-resolution molecular studies remained limited. Reported cases were most often documented in middle-aged and older adults with avian exposure, including pet birds and poultry, and the reported occurrence showed a winter–spring pattern. Pneumonia was the predominant clinical presentation, and severe cases could progress to acute respiratory distress syndrome and multi-organ dysfunction. Metagenomic next-generation sequencing (mNGS) was the most frequently reported diagnostic method in recent studies, while PCR and serology remained important complementary tools. Overall, the literature is growing rapidly, but remains uneven in geographic coverage, study design, and integration across human, animal, and environmental sectors. These findings support broader One Health surveillance, stronger analytic and molecular epidemiology, and more standardized approaches to diagnosis, source investigation, and prevention in China.