Infection In Mainland China Research Articles

Clinical and molecular characteristics of emerging hypervirulent Klebsiella pneumoniae bloodstream infections in mainland China.

Recently, the newly emerged hypervirulent Klebsiella pneumoniae strain (hvKP) has caused great concern globally, but the clinical features and molecular characteristics of bacteremia caused by hvKP are rarely reported in mainland China. Seventy patients with K. pneumoniae bacteremia were investigated to study the clinical features of hvKP infection from 2008 till 2012 in Beijing Chao-Yang Hospital. The molecular characteristics of the hvKP strains were also studied using PCR, multilocus sequence typing, and pulsed-field gel electrophoresis (PFGE) methods. hvKP was identified in 31.4% of the patients with K. pneumoniae bacteremia, which displayed 4 serotypes (K1, K2, K20, and K57). Patients with hvKP infection tended to have no underlying diseases compared to those with classic K. pneumoniae (cKP). More hvKP-positive patients (95.5%) had community-acquired infection than did cKP-infected patients (35.4%) (P<0.001). The 30-day mortality rate was lower in hvKP-infected patients than in cKP-infected patients (4.5% compared to 16.7%). Resistance to tested antimicrobials was significantly greater in cKP- than in hvKP-infected patients. Two extended-spectrum-beta-lactamase (ESBL)-producing hvKP strains were found. Seven novel sequence types (STs) and 4 new alleles of K. pneumoniae were revealed. A strong correlation was found between two STs (ST23, ST1265) and the K1 serotype. The hvKP isolates (n=22) had 14 different PFGE patterns, and among them 10 K1 isolates shared similar PFGE patterns. The emerging hvKP strain was prevalent in patients with severe community-acquired infections in healthy individuals in China. Identification of ESBL-producing hvKP strains in hvKP-infected patients will facilitate clinical management of hvKP infection.

Viral lung infections

The avian influenza A(H7N9) virus has jumped species barrier and caused severe human infections. Here, we present the virological features relevant to clinical practice, and summarize the epidemiology, clinical findings, diagnosis, treatment, and preventive strategies of A(H7N9) infection. As of 18 February 2014, A(H7N9) virus has caused 354 infections in mainland China, Taiwan, and Hong Kong with a case-fatality rate of 32%. Elderly men were most affected. Most patients acquired the infection from direct contact with poultry or from a contaminated environment, although person-to-person transmission has likely occurred. A(H7N9) infection has usually presented with severe pneumonia, often complicated by acute respiratory distress syndrome and multiorgan failure. Mild infections have been reported in children and young adults. Nasopharyngeal aspirate and sputum samples should be collected for diagnosis, preferably using reverse transcriptase-PCR. Early treatment with neuraminidase inhibitors improved survival, but the efficacy of antivirals was hampered by resistant mutants. The closure of live poultry markets in affected areas has significantly contributed to the decline in the incidence of human cases. The emergence of A(H7N9) virus represents a significant health threat. High vigilance is necessary so that appropriate treatment can be instituted for the patient and preventive measures can be implemented.

Detection and Phylogenetic Characterization of a Case of Histoplasma capsulatum Infection in Mainland China

Histoplasmosis usually occurs in specific endemic areas. Sporadic cases have also been reported in mainland China. Here, we described an indigenous case of disseminated histoplasmosis. Phylogenetic analysis revealed that the Histoplasma capsulatum isolated in our case belongs to the Australian clade. Combined with previous studies, it revealed high genetic diversity among Chinese H. capsulatum isolates.

Transmission potential of the novel avian influenza A(H7N9) infection in mainland China

We propose and analyze a mathematical model to mimic its transmission dynamics to assess the transmission potential of the novel avian influenza A(H7N9) virus. By fitting the model to data of the confirmed human cases we estimate the reproduction number for human-to-human transmission as 0.467 (95% CI 0.387–0.651). Simulation results indicate that approximate twofold of the current human-to-human transmission rate or periodic outbreaks of avian influenza in poultry may induce an outbreak in human. Through the recent limited transmission potential of the novel avian influenza A(H7N9) virus, a new outbreak may be possible due to virus mutation and adaption or periodic outbreaks in poultry, and hence careful surveillance and persistent intervention strategies in poultry have to be required.

Kodamaea ohmerias an Emerging Pathogen in Mainland China: 3 Case Reports and Literature Review

Kodamaea ohmeri ( K ohmeri ) is an emerging opportunistic fungal pathogen that infects an increasing number of immunocompromised patients worldwide. Herein, we present 3 cases of K ohmeri infection in mainland China: 1 case of peritonitis and 2 of fungemia. We review the 32 cases described thus far in the English-language medical literature to investigate the characteristics and treatment of K ohmeri infections and to compare the new cases with those described previously. The increase in infections highlights the significance of K ohmeri as a potential yeast pathogen. Early identification and appropriate antifungal therapy, combined with removal of implanted medical devices, greatly influence clinical outcomes. Further studies are required to determine optimal antifungal regimens and to obtain more comprehensive data on the use of novel antifungal agents such as voriconazole and echinocandins. * HIV : human immunodeficiency virus; CAPD : continuous ambulatory peritoneal dialysis; bpm : beats per minute; RBC : red blood cell; HGB : hemoglobin; WBC : white blood cell; PLT : platelet; ip : intraperitoneal; tid : 3 times a day; qn : once a night; iv : intravenously; qd : once a day; bid : twice a day; tiw : three times a week; HBV : hepatitis B virus; CT : computed tomography; q8h : once every 8 hours; q12h : once every 12 hours; ALB : plasma albumin; SCR : serum creatinine; CysC : serum cystatin C; BUN : blood urea nitrogen; AST : serum aspartate aminotransferase; PT : prothrombin time; APTT : activated partial thromboplastin time; PCT : serum procalcitonin; MODS : multiple organ dysfunction syndrome; ICU : intensive care unit; CRRT : continuous renal replacement therapy; CVC : central venous catheter; SDA : Sabouraud dextrose agar; ITS : internal transcribed spacer; PCR : polymerase chain reaction; BLAST : Basic Local Alignment Search Tool; MIC : minimum inhibitory concentration; CLSI : Clinical and Laboratory Standards Institute; MICs : minimum inhibitory concentrations

Spatial analysis of county-based gonorrhoea incidence in mainland China, from 2004 to 2009

Gonorrhoea is one of the most common sexually transmissible infections in mainland China. Effective spatial monitoring of gonorrhoea incidence is important for successful implementation of control and prevention programs. The county-level gonorrhoea incidence rates for all of mainland China was monitored through examining spatial patterns. County-level data on gonorrhoea cases between 2004 and 2009 were obtained from the China Information System for Disease Control and Prevention. Bayesian smoothing and exploratory spatial data analysis (ESDA) methods were used to characterise the spatial distribution pattern of gonorrhoea cases. During the 6-year study period, the average annual gonorrhoea incidence was 12.41 cases per 100000 people. Using empirical Bayes smoothed rates, the local Moran test identified one significant single-centre cluster and two significant multi-centre clusters of high gonorrhoea risk (all P-values <0.01). Bayesian smoothing and ESDA methods can assist public health officials in using gonorrhoea surveillance data to identify high risk areas. Allocating more resources to such areas could effectively reduce gonorrhoea incidence.

Geographic Distribution and Risk Factors of the Initial Adult Hospitalized Cases of 2009 Pandemic Influenza A (H1N1) Virus Infection in Mainland China

BackgroundAs of 31st March 2010, more than 127,000 confirmed cases of 2009 pandemic influenza A (H1N1), including 800 deaths, were reported in mainland China. The distribution and characteristics of the confirmed cases in the initial phase of this pandemic in this country are largely unknown. The present study aimed to characterize the geographic distribution and patient characteristics of H1N1 infection in the 2009 pandemic as well as to identify potential risk factors associated with adverse patient outcome in China, through retrospective analyses of 885 hospitalized cases with confirmed H1N1 infection.Methodology/Principal FindingsThe proportional hazards model was employed to detect risk factors for adverse outcome; the geo-statistical maps were used to characterize the distribution of all 2668 confirmed H1N1 patients throughout mainland China. The number of new cases increased slowly in May, 2009, but rapidly between June and August of the year. Confirmed cases were reported in 26 provinces; Beijing, Guangdong, Shanghai, Zhejiang and Fujian were the top five regions of the incidence of the virus infection. After being adjusted for gender, age, chronic pulmonary disease and other general symptoms, delay for more than two days before hospital admission (HR: 0.6; 95%CI: 0.5–0.7) and delayed onset of the H1N1-specific respiratory symptoms (HR: 0.3; 95%CI: 0.2–0.4) were associated with adverse patient outcome.Conclusions/SignificanceThe 2009 pandemic influenza A affected east and southeast coastal provinces and most populous cities more severely than other regions in mainland China due to higher risk of high level traffic-, high population density-, and high population mobility-associated H1N1 transmission.The clinical symptoms were mild in the initial phase of infection. Delayed hospital admission and delayed appearance of respiratory symptoms were among the major risk factors for poor patient outcome. These findings may have significant implications in the future pandemic preparedness and response.

A novel algorithm to define infection tendencies in H1N1 cases in Mainland China

Incidences of H1N1 viral infections in Mainland China are collected by the Ministry of Health, the People's Republic of China. The number of confirmed cases and the timing of these outbreaks from May 13 to July 22, 2009 were obtained and subjected to a novel mathematical model to simulate the infection profile (time vs number). The model was predicated upon the grey prediction theory which allows assignment of future trends using limited numbers of data points. During the period of our analysis, the number of confirmed H1N1 cases in Mainland China increased from 1 to 1772. The efficiency of our model to simulate these data points was evaluated using Sum of squares of error (SSE), Relative standard error (RSE), Mean absolute deviation (MAD) and Average relative error (ARE). Results from these analyses were compared to similar calculations based upon the grey prediction algorithm. Using our equation, defined herein as equation D–R, results showed that SSE = 6742.00, RSE = 10.69, MAD = 7.07, ARE = 2.47% were all consistent with the D–R algorithm performing well in the estimation of future trends of H1N1 cases in Mainland China. Calculations using the grey theory had no predictive value [ARE for GM(1,1) = −104.63%]. To validate this algorithm, we performed a second analysis using new data obtained from cases reported to the WHO and CDC in the US between April 26 and June 8, 2009. In like manner, the model was equally predictive. The success of the D–R mathematical model suggests that it may have broader application to other viral infections among the human population in China and may be modified for application to other regions of the world.

The neglected arboviral infections in mainland China.

The major arboviral diseases in mainland China include Japanese encephalitis, dengue fever, Crimean-Congo hemorrhagic fever (also known as Xinjiang hemorrhagic fever), and tick-borne encephalitis. These and other newly found arbovirus infections due to Banna virus and Tahyna virus contribute to a large and relatively neglected disease burden in China. Here we briefly review the literature regarding these arboviral infections in mainland China with emphasis on their epidemiology, primary vectors, phylogenetic associations, and the prevention programs associated with these agents in China.

DUPLEX DOPPLER ULTRASOUND OF HEPATIC SCHISTOSOMIASIS JAPONICA: A STUDY OF 47 PATIENTS

This study describes the ultrasound (US) appearances of the liver with hepatic schistosomiasis japonica (HSJ), and studies the portal hemodynamics in 47 patients with HSJ using duplex Doppler US over a period of 15 years. All patients but two were Chinese war veterans seen in Taiwan about 35-55 years after their presumed infection in Mainland China. The US presentations were reviewed. The data from Doppler portal flow studies were available for 39 patients with HSJ, and compared to data from Doppler portal flow studies in 40 normal healthy volunteers and to this data in 40 patients with postnecrotic cirrhosis. A typical "coarse reticular pattern" due to fibrosis in the whole liver was noted in 40 patients (85%). Other findings included periportal fibrosis (15%), septum-like fibrous bands extending to the liver capsule (32%), and an apparent nodular liver surface (19%). Splenomegaly was noted in seven patients. While coexisting hepatocellular carcinomas (HCC) were evident in three patients, and esophageal varices were found in three others, yet both conditions were found only in patients with positive hepatitis-B-surface antigen (HBsAg). Doppler flowmetry of the portal veins in HSJ patients showed a mean flow rate of 15.34 +/- 6.82 cm/sec, and a mean flow volume of 993.21 +/- 290.63 ml/min, both showed no significant difference from those in normal adults (p > 0.5). HSJ can be confidently diagnosed in patients with hepatic fibrosis when the hepatic pathology is presented as a coarse reticular pattern. The portal hemodynamics in HSJ patients who have been isolated from the infection site (for more than 35 years) are significantly different from portal hemodynamics in cirrhotic patients and are similar to those in healthy volunteers.