Objective To analyze the characteristics of the malaria epidemic and the indicators for "1-3-7" from 2021 to 2023 in China, understand the effectiveness and challenges in preventing re-establishment malaria in China, propose response strategies, and provide references for consolidating the achievements of malaria elimination. Methods The individual malaria case data and focus data from 2021 to 2023 in the "Information System for Infectious Disease Surveillance" and the "Information System for Parasitic Diseases Prevention and Control" were collected, and epidemiological characteristics and indicators for “1-3-7” were analyzed. Results From 2021 to 2023, a total of 4 132 malaria cases were reported in 31 provinces and Xinjiang Production and Construction Corps, with mainly falciparum malaria (59.2%, 2 445/4 132). The national malaria epidemic reached a historical low of 799 cases in 2021, before rebounding significantly to 2 488 cases in 2023. The top five provinces for malaria cases were Yunnan, Guangdong, Henan, Sichuan, and Shandong, accounting for 49.4% of the total (2 043/4 132) cases. Except for two long incubation cases infected with P. malariae and one non-mosquito-transmitted case, the remaining cases were imported from abroad, mainly from African countries (81.7%, 3 374/4 129), with P. vivax malaria mainly coming from Myanmar (63.7%, 638/1 001). Malaria cases mainly occur in middle-aged men and migrant overseas workers. 142 severe cases and 21 deaths of malaria were reported. 81.8% (3 378/4 132) of malaria cases sought medical attention within 3 days of symptom onset, and the initial diagnosis institutions were mainly county-level, municipal, and provincial hospitals(77.2%), with an accuracy malaria diagnosis rate of above 80.0%. The completion rates of the malaria indicators for "1-3-7" were all above 90.0%. Conclusions Since the malaria elimination in China, there has been no re-establishment of malaria, and the surveillance response capability has been maintained at a high level. However, the epidemic of imported malaria continued to rise, severely endangering public health in China, especially in areas such as the China-Myanmar border where the risk of re-establishment was high. Currently, it is necessary to further enhance the awareness of the key populations about timely medical consultation for malaria, as well as healthcare workers' vigilance, diagnostic capabilities, and awareness of timely referrals. Efforts should be maintained to investigate and manage epidemics, strengthen prevention and control in key areas such as the China-Myanmar border in Yunnan, and continuously consolidate elimination achievements.
Objective To collect data on imported malaria cases in Jiangsu Province from 2019 to 2023 after malaria elimination and to analyze the current epidemic situation and prevention and control measures of imported malaria, discussing future prevention and control strategies. Methods Malaria case information for Jiangsu Province from 2019 to 2023 was extracted and downloaded from the China Information System for Disease Control and Prevention (CISDCP) as well as the Jiangsu Provincial malaria epidemic database. Statistical analysis was conducted using Stata 12.0 and SPSS 16.0 software. Results From 2019 to 2023, a total of 534 cases of malaria were directly reported online in Jiangsu Province, with annual cases numbering 244, 90, 32, 36, and 132 respectively, all being laboratory-confirmed imported malaria cases from abroad. During the COVID-19 pandemic from 2020 to 2022, the number of imported malaria cases significantly decreased, with several months reporting zero cases. Among the 534 malaria cases, the vast majority were individuals who had traveled to countries in sub-Saharan Africa and Southeast Asia for work, business, international studies, or tourism. Over the five years, the median, minimum, and maximum days for patients from onset of illness to health-seeking were 1(0,12), 1(0,8), 0(0,6), 0(0,10), and 1(0,18) days, with a statistically significant difference in health-seeking time among patients (Fisher's exact test, P=0.03). Over the past three years of the COVID-19 pandemic, compared to outside centralized isolation stations, malaria cases within centralized isolation stations were diagnosed in a shorter time (Fisher exact test, P=0.007). A total of 24 severe malaria cases were reported, with no deaths, including 23 cases of P. falciparum and 1 case of P. ovale. Conclusions After the elimination of malaria, imported malaria cases in Jiangsu Province have sharply decreased due to the impact of the COVID-19 pandemic. Malaria cases in centralized isolation stations (CIS) for COVID-19 control of Jiangsu Province are more likely to be promptly diagnosed, and the timeliness from onset to health-seeking among malaria patients returning from high-malaria areas improved. As COVID-19 prevention and control policies adjusted, there has been a sharp increase in imported malaria cases in 2023. It's still necessary to strengthen measures for malaria prevention and control and maintain the capacity to prevent malaria re-transmission in Jiangsu Province.
Objective To conduct genotyping and molecular tracing analysis on Plasmodium vivax samples from a cluster of P. vivax malaria outbreak in order to provide a reference for case geographical origin determination. Methods Blood samples from 4 patients in a vivax malaria cluster in Longhui County, Hunan Province from June to July 2018 were collected for species identification by qPCR, and 9 microsatellite molecular markers were used to genotype the parasite strains from four samples. The population genetic STRUCTURE analysis was performed based on the VivaxGEN-MS microsatellite genotype database of P. vivax in the Asia Pacific Malaria Elimination Network, to determine the genetic subgroups and geographical origin of the strains. Results By qPCR, all 4 cases were identified as Plasmodium vivax infection, and 9 microsatellite loci of the 4 cases were successfully typed, and the four samples had different genetic haplotypes, among which case 1, case 3, and case 4 were infected by a single clonal strain, and case 2 was infected by a polyclonal strain. When all P. vivax samples were divided into 2 subpopulations (K=2) by STURCTURE analysis, 4 Hunan samples were classified into tropical genetic subpopulations (comprising strains from Ethiopia, Iran, Bhutan, Malaysia, Indonesia, and southern China). When the samples were divided into 4 subgroups by STURCTURE analysis (K=4), the 4 Hunan samples were classified as South Asian/Southeast Asian genetic subgroups (originating from Bhutan, Malaysia, Indonesia, and southern China). Conclusions The results of molecular tracing do not support that the 4 P. vivax strains in this outbreak originated from the population of central China. The technology of molecular tracing of P. vivax can provide objective evidence for determining the source of infection in malaria cases during the stage of malaria elimination and post-elimination.
Objective To analyze and understand the mutations of drug resistance genes in imported Plasmodium falciparum in Shenzhen, aiming to assess the efficacy of antimalarial drugs and guide effective drug use. Methods A total of 85 samples from individuals with imported Plasmodium falciparum confirmed by fluorescence quantitative polymerase chain reaction (PCR) in Shenzhen from 2022 to 2023 were collected and genomic DNA was extracted. Nested PCR was used to amplify resistance genes, including Plasmodium falciparum Kelch 13 (PfK13), multidrug resistance gene 1 (Pfmdr1), chloroquine resistance transporter (Pfcrt), dihydrofolate reductase (Pfdhfr), and dihydropteroate synthase (Pfdhps) genes. Bidirectional sequencing was conducted, and mutations in these resistance genes were analyzed using MEGA11.06 software. Results The study found one missense mutation (S549P) and four synonymous mutations in PfK13. For Pfmdr1, 62.69% of the samples showed Y184F mutation, and no N86Y mutation was detected. No mutations at positions 72 and 73 were detected in the Pfcrt gene, while mutations at M74I, N75E, and K76T accounted for 17.46%, 15.87%, and 15.87%, respectively. The wild-type of Pfcrt gene is dominant (82.54%, 52), followed by the triple mutant I74E75T76 (15.87%, 10). The most common mutation type for Pfdhfr is I51R59N108 (91.78%, 67), followed by the wild type (2.74%, 2). More than half (60.32%, 38) of the Pfdhps samples were wild-type, with single mutation K540E being the most common mutation type. S436A, G437A, K540E, A581G, A613S, I431V, G556K, and G579E site mutations were detected. Among the Pfdhfr-Pfdhps combination mutations, I51R59N108-E540 was the most frequent combination mutation (11.48%), with 59.02% of samples showing solitary Pfdhfr mutations. Conclusions In this study, PfK13 mutation rates were low, with no reported resistance mutations. The Y184F mutation emerged as the dominant Pfmdr1 mutation, with no detection of N86Y. For Pfcrt, the wild-type was dominant, followed by the I74E75T76 triple mutation variant. Triple mutant I51R59N108 of Pfdhfr was very common, and our study did not find Pfdhfr Pfdhps completely resistant and super resistant mutants, but there were other quintuple and septuple mutant types. In the future, it is crucial to continue to strengthen the monitoring of malaria parasite resistance genes and to further integrate in vivo efficacy monitoring to effectively guide clinical drug use.
Objective Through analyzing the epidemiological characteristics of imported Plasmodium falciparum (P. falciparum) cases in China from 2017 to 2022, to understand the trend of imported P. falciparum epidemic before and after malaria elimination, and to provide data support for further prevention and control of imported P. falciparum. Methods Epidemiological questionnaires of P. falciparum cases in 31 provinces (autonomous regions and municipalities directly under the Central Government, excluding Taiwan, Hong Kong, and Macao) and Xinjiang Production and Construction Corps were collected from the parasitic disease control information management system from 2017 to 2022, and the epidemic situation, overseas foci, and distribution of three were statistically analyzed. Results From 2017 to 2022, a total of 7 026 cases of P. falciparum were reported nationwide, accounting for 64.2% (7 026/10 943) of the total number of cases, all of which were imported cases. The infected cases were distributed across 60 countries in 4 continents, mainly in African countries. P. falciparum was reported every month from 2017 to 2022, with uneven distribution throughout the year and a peak occurring at the beginning. The top five provinces with the highest number of P. falciparum malaria cases were Guangdong Province (13.1%, 922/7 026), Jiangsu Province (9.1%, 636/7 026), Shandong Province (8.1%, 569/7 026), Guangxi Zhuang Autonomous Region (7.6%, 537/7 026), and Zhejiang Province (7.6%, 534/7 026). The majority of cases were Chinese nationals (94.9%, 6 668/7 026), with a male-to-female ratio of 17.2∶1. Among the reported cases of P. falciparum, 239 were critically ill and 48 died. Conclusions In the stage of preventing imported malaria retransmission, although all the reported malaria cases in China were imported cases, P. falciparum accounted for the high proportion. Considering the complexity and rapid progression of P. falciparum, which can lead to critical illness or even death, timely detection, accurate diagnosis and standardized treatment of malaria cases should be done to reduce critical illness or death.
Recently, malaria incidence has sharply resurgence in the border area of northern Myanmar, with the parasite incidence rate in 2023 being 21.47 times (95% CI: 18.84-24.48) that of 2019 in Kachin State's Razan and nearby areas. This resurgence caused the number of imported malaria cases to increase from 188 in 2019 to 398 in 2023 in Yunnan Province. In addition to the impact of military conflict, the border malaria joint prevention and control cooperation mechanism and malaria control measures established between China and Myanmar have failed to be implemented effectively due to the impact of the international COVID-19 epidemic. Hence, it is recommended that relevant departments evaluate the quality and effectiveness of the current cross-border transmission measures for malaria in the China-Myanmar border area from a technical perspective, and provide a large demand for primaquine, which can block the spread of malaria and cure vivax malaria, in response to the current prevalent characteristics of vivax malaria predominating in northern Myanmar. Moreover, to effectively reduce the mortality of imported malaria patients and prevent re-importation and transmission, it is necessary to enhance clinical physicians' knowledge, awareness, and vigilance regarding malaria diagnosis and treatment in the Yunnan border region, as well as China's ability and quality of appropriate response to imported malaria.
Malaria is a significant global infectious disease that once wreaked havoc in China as well. In recent years, the global malaria control situation has stagnated, and China is also facing a huge threat of imported malaria. So, effective malaria vaccines are urgently needed as a supplementary strategy to the existing prevention and control measures. Compared to vaccines targeting the erythrocytic stage and those designed to block transmission, vaccines aimed at preventing infection during the pre-erythrocytic stage have attracted more attention and have made a series of progress in recent years. At present, the only two malaria vaccines recommended by the World Health Organization (WHO) are pre-erythrocytic vaccines. In this paper, the current situation and trend of pre-erythrocytic malaria vaccine research and development are reviewed, intending to provide a reference for the research, development, and application of malaria vaccines in the future.
Objective To analyze the causes of death of one case of imported falciparum malaria in Guangxi Zhuang Autonomous Region in January 2023, to provide a reference for the prevention of fatal malaria cases. Methods Interviews were conducted with the doctors who received and consulted the patient, as well as the family members of the patient. Clinical data from the patient's diagnosis and treatment process were collected, and the patient's clinical records and epidemiological investigation data were analyzed. Results The patient, Mr. He, a 53-year-old male from Pingnan County, Guigang City, Guangxi Zhuang Autonomous Region, returned from working in Côte d'Ivoire, Africa, and entered Guangxi on December 26, 2022. He returned home after his centralized quarantine was lifted on January 3, 2023. On January 4th, 2023, the patient developed dizziness and vomiting, considering himself to a possible COVID-19 infection, he did not seek treatment. On the morning of January 6, the patient developed a fever (peak body temperature of 40 ℃), accompanied by fatigue and sore throat, and the preemptive symptoms were aggravated. The patient was admitted to the Guancheng Town Health Center with "Pneumonia" and treated with ribavirin, dexamethasone, ceftriaxone sodium, etc. On January 7, the patient again experienced a high fever (40 ℃) and was discharged to the Emergency Department of the First Affiliated Hospital of Guangxi Medical University. Upon admission, the patient's blood pressure was measured at 78/53mmHg, further comprehensive examination showed a decrease in platelets and abnormalities in liver and renal function, procalcitonin levels at 49.9 ng/mL. Chest CT showed pneumonia, and fluid supplements and antibiotics were given. On January 8, malaria parasites were found in the patient's blood smear, and the patient was diagnosed with malaria (not classified, confirmed as falciparum malaria on January 9th). The patient was recommended to transfer to the provincial malaria-designated hospital, but his family refused. On January 8 at 13:27, the patient excreted approximately 700 g of dark red bloody stools accompanied by blurred consciousness and received hemostasis treatment. After coordinating with multiple parties, four doses of "artemisinin injection " (60 mg/dose) were taken for treatment. At 18:59 on January 8, intravenous administration of 60 mg injectable Artesunate was given, accompanied by symptomatic treatment for fever reduction and rehydration. At 19:40, the patient developed severe hypoglycemia, and severe metabolic acidosis, and blood pressure continued to decrease despite the use of vasopressors. After comprehensive treatment at 3:00 am on January 9, the patient's condition continued to deteriorate, the patient's shock could not be corrected, he lapsed into a coma, and the family requested to be discharged from the hospital. The patient returned home at 7:00 am and died of multiple organ failure at 7:30 am. Conclusions For imported malaria, early and precise diagnosis based on epidemiological history, clinical symptoms, laboratory test results, early antimalarial treatment, and management of organ dysfunction are the keys to avoiding fatal outcomes.
Objective To compare the differences in the expression of interleukin-8 (IL-8) and signal transducer and activator of transcription 3 (STAT3) among three groups of individuals: patients with multi-drug resistant tuberculosis (MDR-TB), patients with drug-susceptible tuberculosis (DSP-TB), and healthy controls. By analyzing the differences between these groups, the study seeks to provide a reference basis for clinical auxiliary diagnosis of new type tuberculosis. Methods The differences in mRNA expression profiles of chip from peripheral blood mononuclear cells (PBMCs) among three groups were analyzed. MDR-TB and DSP-TB patients were selected as study subjects, with healthy individuals serving as a control group, and the serum IL-8 concentration of each group was measured using an ELISA assay to compare differences between groups. Additionally, PBMCs from all groups were isolated and total RNA was extracted for analysis of IL-8 and STAT3 mRNA expression using quantitative real-time PCR(Q-PCR). Differences in STAT3 protein expression among the groups were also compared by Western blot assay. Results The serum IL-8 concentration in the MDR-TB and DSP-TB groups was significantly higher than that in the healthy control group, with a statistically significant difference (P<0.05). The relative expression level of IL-8 mRNA in PBMCs of the MDR-TB group and DSP-TB group was also significantly higher than that of the healthy control group, with a statistical significance (P<0.05). Both Q-PCR and Western Blot results revealed that the expression of STAT3 in the healthy, DSP-TB and MDR-TB groups sequentially increased, presenting statistically significant differences between the groups (P<0.05), consistent with the mRNA chip results. Conclusions The expression of IL-8 in active tuberculosis patients (ATB) is significantly increased, which can be used as a marker to distinguish ATB from healthy populations. The changes of STAT3 concentration not only serve as a reference for the diagnosis of ATB but can also distinguish between DSP-TB and MDR-TB populations. The combined detection of IL-8 and STAT3 holds promise as a clinical auxiliary diagnostic basis for different tuberculosis patients.
Objective To understand the current situation of lung function and nasal inflammation of students from different places of origin, and to explore the possible relationship between air pollutants and lung function and inflammatory factors of healthy college students. Methods A self-designed questionnaire was used to investigate 253 healthy college students, including their basic personal information, the origin of students, and their living environment, then their lung functions were tested, including forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), and peak expiratory flow (PEF). Furthermore, according to the air quality of the region of origin, 60 students from areas with good air quality and 30 students from areas with poor air quality were selected. Nasal inflammatory factors (IL-6 and TNF-α levels) were detected before (July 12, 2019) and after summer vacation (August 27, 2019) to analyze the impact factors on lung function in healthy college students and the level of nasal inflammatory markers after short-term differential exposure to air pollutants. Results The univariate analysis of the questionnaire survey showed that the lung function of healthy college students was influenced by urban-rural distribution, air quality of students' origin, and height. Multivariate analysis found that compared with urban healthy college students, the FVC and FEV1 of rural students increased by 0.346 L and 0.322 L respectively (P<0.05). In addition, for each decrease in the grade of air quality of students' origin, FEV1 and PEF decreased by 0.193 L and 0.687 L/s respectively (P<0.05). After differential exposure to air pollutants during the holiday, healthy college students from areas with poor air quality had higher levels of the nasal mucous membrane inflammatory marker TNF-α than those from areas with good air quality (P<0.05). Conclusions The lung function of healthy college students is affected by urban-rural distribution and the air quality of their region of origin, and the short-term differential exposure to air pollutants leads to changes of nasal inflammatory factors in young healthy individuals.
Objective To analyze the surveillance of Mycobacterium tuberculosis/HIV (TB/HIV) co-infection in Liaoning Province from 2016 to 2021, providing a scientific basis for formulating future prevention and control measures applicable to the province-wide co-infection. Methods A descriptive analysis was conducted on patient registration, two-way screening, and treatment information from the annual report of patients with TB/HIV co-infection in Liaoning Province from 2016 to 2021. Results From 2016 to 2021, 222 cases of TB/HIV co-infection were registered in Liaoning Province, accounting for 0.16% (222/136 709) of TB patients and 1.42% (222/15 584) of HIV/AIDS patients. In HIV/AIDS, the symptom screening rate was 96.01%, showing a downward trend (χ2trend=982.28, P<0.05). The TB detection rate was 0.47%, also showing a downward trend (χ2trend=36.56, P<0.05), while the chest radiograph or sputum detection rate was 94.61%, showing an overall upward trend (χ2trend=96.5, P<0.05). Among TB patients, 65 188 were tested for HIV antibodies, with a detection rate of 47.68%, which showed an overall upward trend (χ2trend=3 326.38, P<0.05). There were 39 HIV-positive cases detected, with the positive detection rate in TB patients decreasing from 0.12% to 0.07%. From 2016 to 2021, the majority of co-infected patients were male and ≥15 years old, with 496 cases (92.36%) of males and 41 cases (7.64%) of females. Among the 537 patients with co-infection, 47 cases (8.75%) received anti-tuberculosis therapy alone, 72 cases (13.41%) received anti-HIV therapy alone, and 408 cases (75.98%) received combined therapy, with an overall downward trend (χ2trend=9.54, P<0.05). Conclusions Focus should be placed on the male population and those aged ≥15 years, with future efforts aimed at enhancing two-way screening work among TB and HIV/AIDS patients and improving the rate of combined treatment.
Objective To study severe fever with thrombocytopenia syndrome virus (SFTSV) in tick samples from different species and genera in Suizhou City, Hubei Province, China, and to explore the phylogenetic relationship between ticks and patients sources of viruses at the molecular evolutionary level. Methods In 2016 and 2017, over a continuous two-year period, 1 158 ticks were collected from Suizhou, Hubei, and their species and genera were identified. Meanwhile, 86 serum samples were collected to detect SFTSV RNA by real-time quantitative reverse transcription-PCR. All viral RNA-positive supernatants of tick homogenates were inoculated into Vero cells for viral isolation, and full genome sequencing of isolated strains was conducted. Phylogenetic tree research on SFTSV strains from ticks and cases was performed using the bootstrapped maximum-likelihood (1 000 iterations) method with Molecular Evolutionary Genetics Analysis (MEGA) software, ver. 11.0 to provide confidence estimates. Results Haemaphysalis longicornis, Ixodes sinensis, and Rhipicephalus microplus were the dominant species (95.34%) in Suizhou City, Hubei Province, China. Tick samples were pooled according to their species and developmental stage, yielding 832 pools, of which 4 were positive for SFTSV by qRT-PCR. The overall minimum infection rate (MIR) in the region was 0.35%. One SFTSV strain named HB 2016-P35, was successfully isolated from Haemaphysalis longicornis and demonstrated high homology to 16 previously reported patient-derived viruses in Hubei Province, especially to the human strain HB 2017-49 from the same region, with a genome similarity of 99.9%. In addition, the molecular phylogenetic analysis revealed five distinct SFTSV genotypes in Hubei, covering almost all currently known SFTSV genotypes. Conclusions Some areas of Suizhou City, Hubei Province, demonstrate a relatively low level of SFTSV carrying and transmission by ticks. The new SFTSV strain isolated from ticks exhibits similar genotype characteristics and high sequence homology with viruses carried by cases in surrounding cases. The study suggests that tick-to-human transmission is most likely the pathway for human infection with SFTSV, highlighting the need for continual and long-term monitoring of tick carriage of SFTSV in endemic areas.
Objective To investigate the expression of T cell immunoglobulin and mucin domain-containing protein 3 (Tim-3) on the surface of T cells in patients with brucellosis (Bm), as well as the expression of interleukin-10 (IL-10) and transforming growth factor beta (TGF-β) in serum, and to analyze the differential expression of these indicators in patients with acute and chronic brucellosis, in order to provide new approaches for the differential diagnosis of acute and chronic brucellosis. Methods A total of 56 patients diagnosed with brucellosis at the First Affiliated Hospital of Xinjiang Medical University from April 2023 to September 2023 were selected, including 31 patients in the acute phase and 25 patients in the chronic phase. Additionally, 35 healthy individuals underwent routine physical examinations within the same period served as healthy controls. Flow cytometry was used to detect and compare Tim-3 levels on the CD4+ T cells' surface among the groups. Levels of serum IL-10 and TGF-β were measured and compared using CBA and ELISA, respectively, and the relationship of these factors with the staging of brucellosis patients was analyzed. Results The proportions of Tim-3+CD3+CD4+T cells in the control group, acute group, and chronic group were (2.56±1.25)%, (5.14±1.98)%, and (13.66±2.66)%, respectively. The Tim-3 levels in the patients with brucellosis were higher than those in the healthy control group, with the chronic group showing even higher levels, and these differences were statistically significant (P<0.05). The levels of IL-10 and TGF in the patient group were higher than those in the healthy control group, with the chronic group exhibiting significantly higher levels of IL-10 and TGF-β than the acute group, also presenting statistically significant differences (P<0.05). The areas under the ROC curve for predicting chronic brucellosis with Tim-3, IL-10, and TGF-β scores were 0.876, 0.865, and 0.663, respectively. Conclusions There are certain differences in the expression of Tim-3, serum IL-10, and TGF-β among patients with brucellosis, with high expression indicating a potential transition to the chronic phase of the disease. Tim-3 has shown the best diagnostic performance. Therefore, as a diagnostic indicator, Tim-3 may provide new ideas and strategies for the treatment and differential diagnosis of brucellosis.
Objective To develop an ELISA kit to detect IgG antibodies of Chikungunya virus (CHIKV), providing a new method for epidemiological investigation and detection in the field for CHIKV infection. Methods Using the CHIKV-specific recombinant protein pMal-chik23 as diagnostic antigen, HRP-labeled anti-IgG antibody as color-developing antibody, and the working concentration of diagnostic antigen, serum to be tested and second antibody were optimized using orthogonal. The reaction conditions of ELISA reaction, such as coating, blocking, incubation, and color-developing were systematically optimized. The cut-off value for ELISA detection was established based on the assessment of a large clinical sample set. On this basis, the specificity, sensitivity, and stability of the ELISA response were evaluated to develop and assemble a rapid ELISA kit for the detection of Chikungunya fever IgG antibodies. Results On the basis of systematic conditions optimization, an indirect ELISA kit for the detection of IgG antibodies against CHIKV was developed and assembled. The optimal reaction conditions were identified as 1.0 μg/mL antigen was coated using carbonate buffer at 4 ℃ for 24 hours. Then the microplate was blocked using HBV blocking solution at 37 ℃ for 4 hours. 100 μL/well samples to be tested were diluted at 1∶101, reacted at 37 ℃ for 40 minutes, and washed 4 times with PBST. Thus, HRP-labeled rabbit anti-human IgG was diluted at 1∶20 000, HRP-labeled sheep anti-mouse IgG was diluted at 1∶10 000, reaction at 37 ℃ for 30 minutes, and washed 5 times with PBST. Finally, 100 μL/well TMB solution was added and incubated at 37 ℃ for 10 minutes. Then terminate the reaction with 50 μL of 20% H2SO4 and measure the A450 value at dual wavelengths of 450/630 nm (A450). The evaluation results showed that ELISA A450 of Chikungunya fever-positive samples were more than 0.43, while the ELISA A450 of negative samples was less than 0.04, and the S/N ratio > 10. Specificity test showed that the developed kit had no cross-reaction with 9 other similar arbovirus species such as Sindbis, Geta, Ross River, and Dengue virus. The stability evaluation of the reagent kit indicated that it had high stability, with a coefficient of variation (CV) within the microplate ranging from 0.76% to 2.12%, the coefficient of variation between the microplate ranged from 0.64% to 1.85%, and the coefficient of variation between batches ranged from 0.83% to 2.31%, all of which were less than 3%. The sensitivity of the kit did not decrease significantly after being stored at 4°C for 1 year. Conclusions A rapid indirect ELISA kit for the detection of Chikungunya fever IgG antibodies was successfully developed, exhibiting good sensitivity, specificity, and stability.
Objective To investigate the influencing factors related to the recent transmission of multidrug-resistant tuberculosis (MDR-TB) in Hainan Province, with the goal of providing an epidemiological basis for the region's prevention and control strategies, as well as clinical decision-making regarding MDR-TB. Methods Clinical respiratory specimens from MDR-TB patients treated at the Second Affiliated Hospital of Hainan Medical University from July 2019 to June 2021 were collected for mycobacterial isolation and cultivation. Isolates of multidrug-resistant Mycobacterium tuberculosis (MDR-MTB) identified through proportional drug-susceptibility screening were subjected to whole-genome sequencing (WGS). In conjunction with clinical and epidemiological data, factors influencing recent MDR-TB transmission were analyzed. Results A total of 202 MDR-TB patients were included in the study, primarily distributed across 18 cities and counties of Hainan Province (excluding Sansha City), and the patients were predominantly male. Phylogenetic analysis of the MDR-MTB strains showed that 56.4% (114/202) belonged to Lineage 2.2 (Beijing), 27.2% (55/202) to Lineage 2.1 (non-Beijing), 13.4% (27/202) to Lineage 4 (Euro-American), and 3.0% (6/202) to Lineage 1 (Indo-Oceanic). Through genetic distance analysis, 42 strains of MDR-MTB were found to be grouped into 15 clusters, with a clustering rate of 20.8%, indicating a significant level of recent transmission. Analysis of transmission-related factors revealed that non-agricultural occupations, initial treatment, and unmarried status were positively correlated with recent MDR-TB transmission, while older age and a history of smoking were negatively correlated. Notably, Lineage 2.2 (Beijing) showed a higher likelihood of MDR-TB transmission compared to Lineage 2.1 (non-Beijing). Multivariate logistic regression analysis further identified that patients receiving initial treatment were an independent risk factor for recent MDR-TB transmission. Conclusions MDR-TB in Hainan Province exhibits distinctive genetic diversity, with Lineage 2.2 (Beijing) being the predominant epidemic strain. Recent transmission of MDR-TB in Hainan Province is associated with non-agricultural occupations, initial treatment, unmarried status, and Lineage 2.2 (Beijing), with the initial treatment being a likely independent risk factor for transmission. These findings offer vital clues for controlling MDR-TB and are expected to guide the formulation of targeted prevention and control strategies to reduce the transmission of the MDR-TB epidemic.
Objective To understand the situation of pulmonary tuberculosis (TB) screening in schools of various levels and types in Guizhou Province, and to provide a scientific basis for strengthening the proactive detection and effective prevention and control measures for TB in key age groups in schools. Methods In 2021, proactive screening and entrance physical examination were conducted for new students and faculty members in Guizhou Province. "Tuberculosis Screening Questionnaire for Schools in Guizhou Province" was filled out, and the physical examination information was uploaded through the "Healthy Guizhou Smart Disease Control Cloud Platform". According to the Prevention and Control Guidelines of China's Learning Schedule (2020 edition), different screening methods were adopted for different physical examination subjects. The main screening methods included three types, namely tuberculin skin test, chest X-ray examination (X-ray chest X-ray), and investigation of suspicious symptoms of pulmonary tuberculosis. Results A total of 1 789 108 students from 18 192 schools were screened, including 1 739 680 new students who underwent physical examinations, 16 922 students who underwent middle and high school entrance examinations, and 32 506 teachers and staff who underwent physical examinations. In 2021, the reported TB incidence rate in Guizhou Province was 85.40 per 100 000, with the highest rates reported in Bijie City, Qiannan Prefecture, and Zunyi City. Symptom screening was conducted for 58 380 individuals across nine cities and prefectures, of which 3 440 individuals (5.89%) presented with suspicious symptoms; PPD tests were conducted for 1 180 442 individuals, with 22 175 cases (1.88%) testing strongly positive; chest X-ray screening involved 366 170 individuals, with 2 837 individuals (0.77%) showing abnormal chest radiographs. The proportion of individuals with suspicious symptoms in public schools (8.11%) was higher than in private schools (1.63%); non-boarding schools had a higher proportion of individuals with suspicious symptoms (6.06%) compared to boarding schools (5.46%). Among the different school types, vocational schools had the highest proportion of individuals with suspicious symptoms (9.09%), while vocational high schools had the lowest (0.32%); these differences were statistically significant (χ2=994.19, 7.69, and 1 257.5, all P<0.01). The proportion of strong positive students in boarding schools (2.15%) was higher than that in non-boarding schools (1.32%), with a statistically significant difference (χ2=981.40, P<0.01); among school types, universities had the highest rate of strong positivity (6.61%), while kindergartens had the lowest (0.59%), with statistically significant differences (χ2=10 707.60, P<0.01). Among different school types, nine-year schools (elementary and junior high) had the highest proportion of abnormal chest radiographs (4.09%), while ordinary secondary vocational schools had the lowest (0.08%), with statistically significant differences (χ2=1 418.191, P<0.01). Conclusions Carrying out physical examination and screening for admission is one of the important measures to reduce the tuberculosis epidemic in schools. The proactive screening work in Guizhou Province needs to be further implemented to achieve full coverage. It is necessary to strengthen the proactive detection of schools in high epidemic areas, especially the screening efforts and health education for key populations such as universities and high schools, to curb the occurrence of TB epidemic in schools.
Objective To investigate the treatment outcomes of patients with pulmonary tuberculosis (PTB) in Xinjiang Production and Construction Corps and to explore the risk factors affecting these outcomes, so as to provide a scientific basis for the prevention and treatment of pulmonary tuberculosis in the corps region. Methods TB patients registered in the Corps from 2016 to 2022 were selected, and the basic demographic and clinical data of the research objects were collected by retrospective method. Log-rank test was used for univariate analysis and the Cox multivariate regression model was used to analyze the influencing factors of treatment outcomes of patients with pulmonary tuberculosis. Results From 2016 to 2022, a total of 8 838 TB patients were registered in the TB Management Information System of Xinjiang Production and Construction Corps, of which 495 cases were untreated, 43 cases had changed diagnoses, 301 cases had no treatment outcomes, 6 cases were diagnosed as extrapulmonary tuberculosis, 11 cases were diagnosed as tracheobronchial tuberculosis, and finally 7 982 TB patients were included in the study. Of the 7 982 patients, 7 578 (94.94%) were treated successfully, while 404 (5.06%) had adverse outcomes (including 32 cases of failure, 13 cases of TB death, 173 cases of non-TB death, 12 cases lost to follow-up, 94 cases of adverse reactions, 10 cases transferred to multi-drug resistance treatment, and 70 other cases). Multivariate Cox regression analysis showed that the >30 to 60-year-old and >60-year-old age groups (OR=1.565, P=0.009; OR=2.960, P<0.001), belonging to ethnic minorities (OR=1.526, P<0.001), being a patients with diabetes mellitus (OR=1.696, P=0.002), current address being in other areas of the province or patients from other provinces (OR=1.419, P=0.004; OR=1.624, P=0.001), receiving retreatment (OR=1.910, P<0.001), and absence of primary care management (OR=1.351, P=0.003) were the risk factors for unsuccessful treatment outcomes in the corps' pulmonary tuberculosis patients. Conclusions The treatment success rate of pulmonary tuberculosis patients in the Corps region is relatively high, but there is still a need to strengthen the treatment and management of the elderly, ethnic minorities, diabetes patients, non-local floating population, retreatment patients and patients who did not receive primary management.
Objective To explore the epidemiological and clinical characteristics of non-tuberculous mycobacterial(NTM) pulmonary disease in Hainan in recent years, and to provide data support for the prevention and treatment of NTM pulmonary disease. Methods Medical records of patients diagnosed with NTM pulmonary disease who treated at the Second Affiliated Hospital of Hainan Medical University (Hainan Provincial Tuberculosis Hospital) from January 2018 to December 2022 were collected. The demographics, regional distribution, temporal distribution, distribution of mycobacterial species, clinical symptoms, and radiological imaging changes of these patients were analyzed. Results A total of 225 confirmed cases of NMT pulmonary disease were collected in this study, with 133(59.1%) female patients outnumbering 92(40.9%) male patients. The disease predominantly affected people over 50 years old, with 192 cases (85.3%), and the major onset age range was 61-<81 years old, with a median age of 63 and an average age of 62. Farmers comprised the majority of the patients, with 112 cases (49.8%). More patients were from the western region (90 cases, 40.0%) than from the central region (76 cases, 33.8%), followed by the eastern region (59 cases, 26.2%). A total of 10 strains were detected from 225 samples, with the most common strains being Mycobacterium intracellulare (92 cases, 40.9%), Mycobacterium chelonae/abscessus(80 cases, 35.6%), and Mycobacterium avium (15 cases, 6.7%), followed by Mycobacterium kansasii (5 cases, 2.2%), Mycobacterium fortuitum (4 cases, 1.8%), and Mycobacterium parascrofulaceum (3 cases, 1.3%). There were 10 cases (4.5%) of mixed infections, including Mycobacterium avium and Mycobacterium intracellulare (8 cases, 3.6%), Mycobacterium intracellulare and Mycobacterium chelonae/abscessus (1 case, 0.4%), and Mycobacterium fortuitum and Mycobacterium chelonae/abscessus (1 case, 0.4%). The primary clinical manifestations of NTM pulmonary disease included cough and sputum (219 cases, 97.3%), hemoptysis (92 cases, 40.9%), fever (61 cases, 27.1%), dyspnea (57 cases, 25.3%), night sweats (52 cases, 23.1%), weight loss (50 cases, 22.2%), and thoracodynia (35 cases, 15.6%). There was no significant difference in symptoms between male and female patients. Pleural thickening (188 cases, 83.6%) and bronchiectasis (151 cases, 67.1%) were the most common imaging changes in NTM pulmonary disease, followed by cavities (93 cases, 41.3%), emphysema (41 cases, 18.2%), and lung damage (28 cases, 12.4%). Male patients were more likely to have lung damage and emphysema, while female patients were more likely to have bronchiectasis. Conclusions The distribution of NTM species is diverse in Hainan area, with Mycobacterium intracellulare, Mycobacterium chelonae/abscessus, and Mycobacterium avium are dominant species. NTM pulmonary disease and pulmonary tuberculosis have similar clinical features, which requires attention for differentiation in clinical practice.
Objective To analyze the molecular serotyping and drug resistance of foodborne Listeria monocytogenes (LM)isolates from the food monitoring network of Liaoning Province, and to provide a reference for identifying and tracing the outbreaks of foodborne diseases. Methods The Listeria monocytogenes isolates were identified, biochemical typing was conducted by VITEK biochemical identification and PCR amplification techniques were applied for molecular serotyping of 67 strains of Listeria monocytogenes detected from 2 797 food samples collected from 15 monitoring sites across the province during 2021-2022. Verification was performed according to the instructions of the serodiagnosis manual. The sensitivity of the strains to ampicillin, penicillin, meropenem, cotrimoxazole, and erythromycin was determined by broth dilution method. Results In food from Liaoning Province, the molecular serotypes of Listeria monocytogenes carried were identified as 1/2a(3a), 1/2b(3b, 7), 1/2c(3c), and 4b (4d, 4e), with the predominant serotypes being 1/2a accounting for 62.7% (42/67), and 1/2b accounting for 28.4% (19/67). Among them, the 4b strain was isolated in 3 strains, representing 4.5%. The dominant strains of Listeria monocytogenes in 2021 and 2022 in Liaoning Province were 1/2a(3a) and 1/2b(3b, 7), with the most diverse types carried by meat and meat products. Double resistance to cotrimoxazole and erythromycin accounted for 11.9% (8/67), while resistance to only one cotrimoxazole accounted for 9.0% (6/67). Conclusions The presence of pathogenic serotypes 1/2a(3a), 1/2b(3b, 7), 1/2c(3c), and 4b (4d, 4e) in food in Liaoning Province and the emergence of strains with one or more drug resistances indicate the existence of food safety issues caused by Listeria monocytogenes, posing a potential risk of listeriosis. There is a need to optimize source tracing methods and strengthen the confirmation of Listeria monocytogenes outbreaks.
Objective To express Mycobacterium tuberculosis Rv2626c protein in Escherichia coli (E. coli) and study the antigenicity of the purified recombinant Rv2626c protein. Methods The amino acid sequence of Rv2626c protein from Mycobacterium tuberculosis H37Rv strain (accession number: CCP45424.1) in GenBank was retrieved and converted into the corresponding DNA sequence according to the codon preference of E. coli. This DNA sequence was synthesized and cloned into pET24a(+) plasmid to construct pET24a(+)-Rv2626c recombinant plasmid. This plasmid was transformed into E. coli BL21(DE3) cells, and the expression of Rv2626c protein was induced under various conditions of isopropyl β-D-thiogalactopyranoside (IPTG) concentrations, temperature, and period. The recombinant Rv2626c protein was identified by SDS-PAGE and Western Blot. The recombinant Rv2626c protein was purified by nickel chelate affinity chromatography and used to immunize violet blue rabbits to prepare anti-Rv2626c anti-serum. The specificity and titer of the serum were respectively detected by Western Blot and enzyme-linked immunosorbent assay (ELISA). Results The recombinant plasmid pET24a(+)-Rv2626c was successfully constructed. SDS-PAGE analysis showed that recombinant Rv2626c was expressed in the recombinant plasmid transformed E. coli with IPTG induction, with a molecular weight of about 14 500, and the size was consistent with the expectation. The optimal expression condition for recombinant Rv2626c protein was at 31 ℃ with 1.0 mmol/L IPTG for 6 hours. The target protein was mainly present in a soluble form, which was consistent with the results of Western blot. The hyperimmunized serum with recombinant Rv2626c protein vaccination showed good specificity, with a titer of 1∶ 256 000 detected by ELISA. Conclusions Mycobacterium tuberculosis Rv2626c protein is successfully expressed in E. coli, and the purified protein has good purity and antigenic activity, laying the foundation for further reveals of its biological functions.
More than 300 mosquito-borne arboviruses have been found worldwide, among which Dengue virus, Chikungunya virus, Japanese encephalitis virus, West Nile virus, and Zika virus are circulating around the world, causing a huge public health burden and arousing widespread concern in the whole society. China's vast territory and complex geographical landscapes are suitable for the reproduction of various mosquito-borne arboviruses, so the species and geographical distribution of mosquito-borne arboviruses in China have attracted much attention. Since the 1980s, 38 mosquito-borne arboviruses belonging to nine families, including Flaviviridae, Bunyaviridae, Togaviridae, and Reoviridae, have been isolated and identified from more than 1 million mosquitoes and human and animal specimens collected across China by means of tissue cell culture and animal inoculation. The results of field and laboratory tests indicate the existence of various mosquito-borne arboviral diseases in China, including Japanese encephalitis, Dengue fever, West Nile encephalitis, and febrile diseases caused by Tahyna virus infection. This study summarizes the species and geographical distribution of mosquito-borne arboviruses, mosquito-borne arboviruses, and their vectors, and mosquito-borne arboviral infectious diseases in China, providing technical support for the control and prevention of mosquito-borne arbovirus and their corresponding diseases, endemic management, disease early warning and prediction. Joint prevention and control of arboviral diseases in Asia and even the world is also of long-term and practical significance.
To investigate the clinical features of one case of imported dengue fever, and to clarify the key points of its diagnosis and prevention. One case of dengue fever confirmed in the First Affiliated Hospital of Bengbu Medical University on September 1, 2023 was selected, and the clinical manifestations and epidemiological data were retrospectively analyzed, along with testing for the dengue virus nucleic acid in the patient. The patient had a history of travel and residence in the Maldives, and developed symptoms such as fever, chills, accompanied by muscle aches, and scattered rashes on both lower limbsfollowing exposure to cold, with a positive dengue virus nucleic acid test. After symptomatic treatment with nutritional support, antipyretic, rehydration, hemostasis, and elevated granulocytes, the patient was discharged from the hospital with improvement. The clinical manifestations of dengue fever are complex and diverse, and the collection of medical history should consider the patient's travel history abroad. Currently, there is no specific anti-dengue virus drug, and symptomatic and supportive treatment is mainly adopted.
To investigate the clinical features, early recognition and prognosis of influenza-associated intracranial aspergillosis. The clinical data of a child with influenza-related intracranial aspergillosis admitted to the Department of Pediatrics of the Third Xiangya Hospital of Central South University in 2022 were retrospectively analyzed. By searching CNKI, Wanfang Database, Web of Science, PubMed and other Chinese and English databases as of November 2023, literature was screened according to inclusion and exclusion criteria, and the clinical characteristics, diagnosis, treatment and prognosis of all influenza-related intracranial aspergillus disease were summarized. A total of 5 reports of 5 cases of influenza-associated aspergillosis were obtained, including 1 child patient and 1 child influenza-associated intracranial aspergillosis in this study, and a total of 6 influenza-associated aspergillosis patients. The clinical manifestations of the 6 patients were disturbance of consciousness, hemiplegia, pupil changes, behavioral abnormalities, epilepsy, etc. Most of the cases were diagnosed through pathology or autopsy to find pathogens. In this case, the pathogens were confirmed through metagenomic next-generation sequencing (mNGS). Antifungal drugs were the first choice for treatment. 66.7% of the surviving patients received surgical treatment, and the mortality rate of 6 patients reached 50.0%. Influenza-associated intracranial aspergillosis is rare, can occur in both children and adults, and has a poor prognosis. In the early stage of influenza, if there are neurological symptoms, screening for fungal infection should be conducted. Acer second generation sequencing can improve the diagnosis rate of intracranial aspergillosis.
To investigate and analyze the causes of a human brucellosis epidemic in Chengjiang City in 2023 through field epidemiological investigation, and to provide a reference for future surveillance and control. A field epidemiological investigation of the case was carried out, with an active search of cases in epidemic areas. Samples from high-risk individuals, sheep, and dogs in the epidemic area were collected for brucellosis testing and pathogen isolation and culture, and the data were statistically analyzed by descriptive epidemiological method. One case of human brucellosis was detected in the outbreak, with smooth Brucella glabrata (ovine biotype 3) isolated from the patient's blood. Smooth Brucella glabrata antibodies were detected in two samples from the patient's dogs, with a positive rate of 16.67%. Tests for brucellosis in high-risk individuals and goats were negative, leading to a determination that this was an outbreak of ovine brucellosis transmitted from dogs to humans. This outbreak represented a rare instance of Brucella glabrata (ovine biotype 3) co-infected by humans and dogs. In dealing with the epidemic of human brucellosis, it is necessary to expand ideas and methods, strengthen the prevention and control of canine brucellosis, pay attention to the infection of dogs, and raise the protection awareness of dog farmers.
