中国疾病预防控制中心周报最新文献

What is already known about this topic?: A substantial proportion of people living with human immunodeficiency virus (PLWH) remain unaware of their infection status. Contact tracing serves as an effective public health tool for identifying human immunodeficiency virus (HIV) infections and supports progress toward achieving the 95-95-95-95 goals.

What is added by this report?: An egocentric contact tracing study conducted in Yunnan, China, between January 2022 and June 2024 enrolled 1,981 index cases, of whom 314 (15.9%) had at least 1 HIV-positive sexual contact. These index cases reported 2,171 sexual contacts, with 1,509 (69.5%) receiving HIV testing and 317 (21.0%) testing positive. Higher education levels and employment status among sexual contacts were positively associated with HIV testing uptake. HIV infection was more likely among contacts when the index case was female and identified through active HIV testing. Long-term sexual partnerships and inconsistent condom use demonstrated elevated infection risk.

What are the implications for public health practice?: The effectiveness of contact tracing outcomes is influenced by characteristics of both index cases and their sexual contacts. These factors should be incorporated into the design and implementation of sexual contact tracing programs.

Introduction: This study aimed to provide a comprehensive analysis of the human immunodeficiency virus (HIV) epidemiological landscape in China through a historical review and current assessment.

Methods: Data were extracted from China's HIV/AIDS Comprehensive Response Information Management System (CRIMS). Transmission patterns across different phases were visualized using stacked area charts. Geographical correlations between transmission routes were analyzed using scatter plots and Pearson correlation coefficients. The extent and trends of HIV spread among the general population were evaluated using Venn diagrams and Cochran-Armitage tests.

Results: The HIV epidemic in China evolved through four distinct phases: injecting drug user (IDU) dominated (1989-1994), former plasma donor (FPD) outbreak (1995-2005), sexual transmission dominance (2006-2014), and general population spread (2015-present). A strong correlation was observed between provinces reporting high numbers of IDU cases and those with elevated heterosexual transmission (r=0.88, P<0.001). Between 2015 and 2023, 393,926 cases were identified among the general population through non-marital and non-commercial heterosexual contact (NMNCHC). The proportion of general population cases among heterosexual transmissions increased significantly from 46.2% to 55.7% (Z=42.7, P<0.001).

Conclusion: The significant spread of HIV into the general population necessitates the development of targeted prevention strategies for both high-risk and general populations to address emerging epidemiological challenges.

Introduction: A comprehensive analysis of nationwide survival trends for people living with human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS, PLWHA) from the initial reported case to present has not been conducted. This study evaluated the survival outcomes of PLWHA reported in China from 1985 to 2022.

Methods: We analyzed data from PLWHA recorded in the National HIV/AIDS Comprehensive Response Information Management System from 1985 to 2022. Survival rates were calculated using Kaplan-Meier curves, and factors associated with survival time were analyzed using Cox proportional hazard models.

Results: Progressive relaxation of antiretroviral therapy initiation criteria led to significant improvements in survival rates across different diagnostic periods in China. The 1-year and 5-year cumulative survival rates increased from 85.2% and 66.1% in the 1985-2003 cohort to 91.1% and 81.4% in the 2016-2022 cohort. Cox proportional hazard analysis revealed elevated mortality risks among males, individuals aged ≥65 years, those with injection drug use or other transmission routes, hospital-tested patients, and those with lower CD4 counts at diagnosis or without treatment.

Conclusions: Antiretroviral therapy has effectively reduced mortality risk among PLWHA in China. Future efforts should focus on expanding HIV testing to reduce the proportion of late diagnoses with lower CD4 counts and providing targeted, differentiated services for older populations to further decrease mortality risk among PLWHA.

What is already known about this topic?: The emergence of rare multidrug-resistant Salmonella serovars is increasingly common in developing countries, posing a significant public health risk.

What is added by this report?: This report identified five rare Salmonella serovars in China for the first time and using whole-genome sequencing, identified their hidden spread among healthy individuals. Additionally, antibiotic resistance genes and virulence genes were identified.

What are the implications for public health practice?: Healthy individuals, especially food handlers, may be sources of hidden Salmonella dissemination. Therefore, monitoring Salmonella prevalence in healthy individuals is important for understanding and managing the risks of foodborne illness.

What is already known about this topic?: Neisseria meningitidis (Nm) is a bacterial pathogen that causes meningococcal disease. Serogroups A, B, C, W, X, and Y account for the vast majority of cases. However, invasive meningococcal disease (IMD) caused by NmY is rare in China and has been reported only in Tianjin, Guangdong, Shanghai, and Hunan provinces and cities.

What is added by this report?: This article reports the first case of NmY:cc23 meningococcal disease in Hebei Province, confirmed by metagenomic sequencing. We also present the results of expanded surveillance in the healthy population associated with the case.

What are the implications for public health practice?: NmY has caused multiple case reports across China, especially in southern cities. The first report of a serogroup Y case in Hebei Province, and the carriage rate in the healthy population, reminds us to increase public health attention on Nm. The results of this study suggest that surveillance of the Nm carriage rate among healthy carriers and serogroup changes in Nm should be strengthened.

Introduction: Enterococci are considered opportunistic pathogens. However, they can serve as a reservoir of antibacterial resistance (ABR) traits and transfer these to humans through the food chain.

Methods: Antibiotic susceptibility testing and multilocus sequence typing were used to characterize the ABR and population structure of 488 enterococcal isolates recovered along the food chain from four provincial-level administrative divisions (PLADs) in China.

Results: Enterococcus faecalis (E. faecalis) was the dominant species cultured from pig farms and retail meat, while Enterococcus faecium (E. faecium) and Enterococcus casseliflavus were dominant in patients with diarrhea and retail fruits and vegetables, respectively. Approximately 67% of all Enterococcus isolates were multidrug-resistant (MDR). E. faecium resistance to ampicillin and penicillin was significantly higher than that of E. faecalis. The E. faecalis isolates exhibited substantially heterologous sequence types (STs), whereas E. faecium isolates were clearly divided into clonal complex (CC) CC17 and CC94 clades. E. faecium isolates were mainly detected in hospitalized children and were identified as the hospital-associated CC17 clade with ampicillin and penicillin resistance. Notably, E. faecalis ST16 and ST65 and E. faecium ST60 and ST94 detected in patients with diarrhea were also detected in farm and food samples, indicating that these STs should be closely monitored. The community-lineage E. faecium CC94 clade was detected in patients with diarrhea, implying that community isolates might find their way into hospitals.

Conclusion: This study highlights the One Health challenges posed by enterococci important to human health and the need to implement integrated preventive measures for their control.

What is already known about this topic?: Salmonella enterica is a significant foodborne pathogen responsible for millions of infections and thousands of deaths worldwide each year. The increasing prevalence of the ST34 Salmonella enterica serotype 4,5,12:i:-(S. 4,[5],12:i:-) poses a substantial public health threat in China.

What is added by this report?: At the end of 2023, the TraNet early-warning module, utilizing whole-genome sequencing data, identified a newly regionally prevalent sequence type of S. 4,[5],12:i:-, designated ST8333, primarily found in Sichuan Province. Analysis revealed high rates of antimicrobial resistance genes, particularly to aminoglycosides and β-lactams. Plasmid comparisons suggest that ST8333 isolates acquired multidrug-resistance plasmids of swine origin during their distribution in Sichuan Province.

What are the implications for public health practice?: The emergence of ST8333, likely associated with pork consumption, underscores the importance of food safety measures. The high prevalence of multidrug resistance poses challenges for treatment and highlights the need for vigilant surveillance and control measures. Strengthening efforts in regions like Sichuan, identified as a reservoir for multidrug-resistant ST8333 strains, is crucial to prevent further transmission and potential nationwide dissemination. Surveillance and control measures are imperative to curb the spread of multidrug-resistant ST8333 isolates, particularly in high-prevalence regions.

What is already known about this topic?: Visceral leishmaniasis (VL), transmitted by sandflies, is a zoonotic disease of public health importance in central and western China.

What is added by this report?: A number of VL hotspots were identified in the border areas of Shanxi-Hebei, Shanxi-Shaanxi, Gansu-Sichuan, as well as the southern Xinjiang provincial-level administrative division (PLAD). Mountain zoonotic visceral leishmaniasis (MT-ZVL) expanded rapidly in the mountainous regions of Shaanxi, Shanxi, Henan, Hebei, Beijing, and Gansu PLADs from 2011 to 2022. A notable resurgence of MT-ZVL has occurred, with 671 cases in 66 historically endemic counties.

What are the implications for public health practice?: Actions are recommended to restrain the rapid expansion of MT-ZVL: Firstly, implement One Health approaches, such as timely diagnosis and treatment of patients, promoting insecticide-impregnated dog collars, and restraining the number of dogs in endemic areas. Secondly, surveillance-response systems for sandflies and infective dogs in potential risk areas should be strengthened.

Background: Recent plague cases in Inner Mongolia prompted research on rodents and fleas. This study aimed to describe the spatiotemporal characteristics of parasitic fleas on predominant rodent species and identify plague risk areas.

Methods: We assembled monitoring data from the National Plague Surveillance System for 12 regions in Inner Mongolia from 2013 to 2021. We performed descriptive statistics using relative indices, analyzed interannual flea index trends using the Mann-Kendall test, compared spatiotemporal characteristics using the Kruskal-Wallis H test and Dunn's test, and delineated plague risk areas based on cluster analysis.

Results: In total, 134,181 rodents from 28 species were captured, with an average parasitism rate of 31.46%. A total of 143,958 fleas were collected, resulting in a total average flea index of 1.07. The primary rodent species were the Mongolian gerbil ( Meriones unguiculatus) and Daurian ground squirrel (Spermophilus dauricus). The flea index showed a decreasing trend (Sen's slope=-0.06, P<0.05). Meriones unguiculatus had two peaks (May and October), with a delay of one to two months after peak flea parasitism. Spermophilus dauricus had a peak in May but two flea parasitism peaks (March and November). Meriones unguiculatus and Spermophilus dauricus flea indices varied significantly across regions (H=25.75, P<0.001; H=29.88, P<0.001). Erdos City and Xilingol League had the highest flea indices for each species, respectively. Cluster analysis divided the 12 regions into three risk zones.

Conclusions: The two predominant rodent species in Inner Mongolia have demonstrated an overall decline in flea index over time. The hotspots for flea index are primarily concentrated in Erdos and Xilingol League. Strengthening regional cooperation is crucial for tailored plague prevention and control measures.