[Analysis of clinical characteristics and prognosis of 4 264 patients with asymptomatic and mild novel coronavirus infections in Shanghai].

OBJECTIVE: To analyze the clinical characteristics and prognosis of patients infected with novel coronavirus Omicron variant in Shanghai, as to provide a reference for epidemic prevention, clinical diagnosis, and treatment. METHODS: Altogether 4 264 novel coronavirus Omicron variant-infected patients with positive results of nucleic acid admitted to Shanghai New International Expo Center N3 Mobile Cabin Hospital from April 2 to May 7, 2022, were included. The demographic and baseline clinical characteristics, treatment strategy, prognosis, and different factors affecting the length of hospital stay were analyzed. RESULTS: A total of 4 264 novel coronavirus variant Omicron-infected cases were collected, including 3 111 cases (73.0%) asymptomatic infections and 1 153 cases (27.0%) mild infections. The overall median age was 45 (33, 55) years old with a range from 2 years old to 81 years old. The male to female ratio was 1.37:1. Altogether 3 305 cases (77.5%) had been vaccinated, of which 3 166 cases completed more than 2 doses. The upper respiratory tract symptoms such as cough and expectoration were the most common clinical manifestations of these infected patients. During the course of the disease, patients with asymptomatic infection were mainly treated with traditional Chinese medicine (TCM, 55.1%) and clinical observation (36.8%), and those with mild infection were mainly treated with TCM (42.2%) or integrated Chinese and Western medicine (30.4%). All patients were cured and discharged. The overall median length of hospital stay and the negative conversion time of nucleic acid were 9 (6, 10) days and 8 (5, 9) days, respectively. Compared with the asymptomatic infected patients, the hospitalization duration and the nucleic acid negative conversion time of the mildly infected patients were slightly longer [days: 10 (8, 11) vs. 9 (5, 10); 8 (6, 10) vs. 7 (4, 9), both P < 0.001]. Multiple linear regression analysis showed that the increasing age and mild infection were associated with longer hospitalization duration, and the treatment of TCM or integrated Chinese and Western medicine was associated with shortened length of hospital stay (all P < 0.05). CONCLUSIONS: The current novel coronavirus Omicron variant epidemic in Shanghai mainly caused asymptomatic and mild infections. The young and middle-aged population had a relatively high infection rate. The upper respiratory tract symptoms such as cough and expectoration were the most common clinical symptoms. Elderly and confirmed patients had prolonged hospitalization duration, while for patients receiving TCM treatment, the hospitalization duration was shortened.

SARS-CoV-2 infection in pregnant women assisted in a high-risk maternity hospital in Brazil: Clinical aspects and obstetric outcomes.

BACKGROUND: The spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, the possible development of serious illness, and the possibility of severe obstetric outcomes highlight the importance of addressing SARS-CoV-2 infection in obstetric management. METHODS AND FINDINGS: A cross-sectional study of pregnant women assisted in a high-risk maternity hospital in Brazil in 2020. All patients admitted for delivery or miscarriage care were tested for SARS-CoV-2 using polymerase chain reaction (PCR) and for immunoglobulin (I)gM, and/or IgG by immunochromatography. Clinical aspects and obstetric outcomes were analyzed. A total of 265 pregnant women were included in the study. There were 38 (14.4%) PCR positive cases during pregnancy, 12 (31.6%) on admission screening, and 71(27.2%) patients were IgM- and/or IgG-positive. Among the participants, 86 (32.4%) had at least one positive test during pregnancy. SARS-CoV-2 positive patients had greater contact with known positive patients (p = 0.005). The most frequently reported symptoms were runny nose, cough, loss of smell and taste, headache, and fever. There was also a 35% rate of asymptomatic infections and a 4.6% rate of severe or critical infections. Patients exposed or infected with SARS-CoV-2 had a higher incidence of preterm delivery, cesarean section, need for resuscitation in the delivery room, Apgar score <7 at 5 min, admission to the neonatal intensive care unit, and jaundice. Newborns with at least one positive test had a significantly greater need for phototherapy after delivery (p = 0.05). The results showed a high rate of positive tests among newborns (37.5%), which seems to be compatible with both neonatal and perinatal infection. CONCLUSIONS: It is important to further investigate SARS-CoV-2 infection during pregnancy, including the clinical course and the possibility of adverse outcomes with impact on maternal and fetal health, regardless of the development of symptoms.

Clinical characteristics and viral shedding kinetics of 38 asymptomatic patients with coronavirus disease 2019: A retrospective observational study.

ABSTRACT: This study aims to investigate the clinical characteristics and viral shedding kinetics of asymptomatic patients with coronavirus disease 2019 (COVID-19).The data of 38 asymptomatic patients positive for SARS-CoV-2 nucleic acid were collected from February to March 2020 in Tuanfeng County, Huanggang, Hubei, China. The epidemiology, laboratory examination, chest imaging, viral nucleic acid test results, clinical characteristics, and viral shedding time were summarized in this retrospective study.The study included 20 family members of patients with COVID-19, 10 medical personnel participating in COVID-19 treatment or working in a fever clinic, 6 personnel from quarantine places, 1 individual with a close contact history with confirmed patients, and 1 local epidemic prevention personnel. All were positive for SARS-CoV-2 nucleic acid. The white blood cell (WBC) count, the absolute value of lymphocytes, C-reactive protein (CRP), and D-dimer were normal. Pneumonia manifestations were not found in the chest computed tomography (CT) scan of 36 patients; the remaining 2 cases included a 1-year-old child and a pregnant woman, and they did not undergo chest CT. The viral shedding time was 6 days.All asymptomatic patients with COVID-19 had a history of close contact or exposure. Laboratory tests were normal. Chest imaging did not show any pneumonia manifestation. The viral shedding time was <10 days, which is shorter than that of patients with COVID-19. A timely discovery of such asymptomatic infections is crucial for blocking the spread of the virus and strengthening the prevention and control measures.

Asymptomatic pharyngeal carriage rate of Streptococcus pyogenes, its associated factors and antibiotic susceptibility pattern among school children in Hawassa town, southern Ethiopia.

OBJECTIVES: The aim of this study was to determine the asymptomatic pharyngeal carriage rate of S. pyogenes, antimicrobial pattern and related risk factors among school children in Hawassa, southern Ethiopia. RESULTS: Out of 287 school children's screened, 35 (12.2%) were colonized with S. pyogenes. The carriage rate was significantly associated with factors such as sex (female p = 0.013) occupational status of mother (p = 0.002), lower income source (500-900 ETB, 1000-1500 ETB) (p = 0.001, and p = 0.042), history of hospitalization (p = 0.00) and residence of the children (p = 0.002). High level resistant to tetracycline and low level to vancomycin were observed, while penicillin, amoxicillin, erythromycin, chloramphenicol, and ceftriaxone were found to be effective.

Presence of Giardia lamblia in stools of six- to 18-month old asymptomatic Malawians is associated with children's growth failure.

AIM: Despite high pathogen burden and malnutrition in low-income settings, knowledge on relationship between asymptomatic viral or parasitic infections, nutrition and growth is insufficient. We studied these relationships in a cohort of six-month-old Malawian infants. METHODS: As part of a nutrient supplementation trial for 12 months, we documented disease symptoms of 840 participant daily and anthropometric measurements every three months. Stool specimens were collected every six months and analysed for Giardia lamblia, Cryptosporidium species and enterovirus, rotavirus, norovirus, parechovirus and rhinovirus using polymerase chain reaction (PCR). The prevalence of the microbes was compared to the children's linear growth and the dietary. RESULTS: The prevalence of the microbes was similar in every intervention group. All age groups combined, children negative for G. lamblia had a mean standard deviation (SD) of -0.01 (0.49) change in length-for-age Z-score (LAZ), compared to -0.12 (0.045) among G. lamblia positive children (difference -0.10, 95% CI -0.21 to -0.00, p = 0.047). The LAZ change difference was also statistically significant (p = 0.042) at age of 18-21 months but not at the other time points. CONCLUSION: Asymptomatic G. lamblia infection was mainly associated with growth reduction in certain three-month periods. The result refers to the chronic nature of G. lamblia infection.

Whole Genome Sequencing detects Inter-Facility Transmission of Carbapenem-resistant Klebsiella pneumoniae.

OBJECTIVES: To identify transmission patterns of Carbapenem-resistant Klebsiella pneumoniae infection during an outbreak at a large, tertiary care hospital and to detect whether the outbreak organisms spread to other facilities in the integrated healthcare network. METHODS: We analyzed 71 K. pneumoniae whole genome sequences collected from clinical specimens before, during and after the outbreak and reviewed corresponding patient medical records. Sequence and patient data were used to model probable transmissions and assess factors associated with the outbreak. RESULTS: We identified close genetic relationships among carbapenem-resistant K. pneumoniae isolates sampled during the study period. Transmission tree analysis combined with patient records uncovered extended periods of silent colonization in many study patients and transmission routes that were likely the result of asymptomatic patients transitioning between facilities. CONCLUSIONS: Detecting how and where Carbapenem-resistant K. pneumoniae infections spread is challenging in an environment of rising prevalence, asymptomatic carriage and mobility of patients. Whole genome sequencing improved the precision of investigating inter-facility transmissions. Our results emphasize that containment of Carbapenem-resistant K. pneumoniae infections requires coordinated efforts between healthcare networks and settings of care that acknowledge and mitigate transmission risk conferred by undetected carriage and by patient transfers between facilities.

Asymptomatic Bacteriuria in Noncatheterized Adults.

Asymptomatic bacteriuria (ASB) is a common finding and frequently detected in premenopausal nonpregnant women, institutionalized patients, patients with diabetes mellitus, and the ambulatory elderly population. Despite clear recommendations regarding diagnosis and management of ASB in these populations from the Infectious Diseases Society of America (IDSA), there remains an alarming rate of antimicrobial overuse. This article reviews definitions of ASB, epidemiology of ASB, literature surrounding ASB in diabetic patients, risk factors of ASB, microbiologic data regarding bacterial virulence, use of ASB strains for treatment of symptomatic urinary tract infection, and approaches to addressing translational barriers to implementing IDSA recommendations regarding diagnosis and management of ASB.

Asymptomatic bacteriuria treatment is associated with a higher prevalence of antibiotic resistant strains in women with urinary tract infections.

BACKGROUND: Women suffering from recurrent urinary tract infections (rUTIs) are routinely treated for asymptomatic bacteriuria (AB), but the consequences of this procedure on antibiotic resistance are not fully known. The aim of this study was to evaluate the impact of AB treatment on antibiotic resistance among women with rUTIs. METHODS: The study population consisted of 2 groups of women who had previously been enrolled in a randomized clinical trial: group A was not treated, and group B was treated. All women were scheduled for follow-up visits every 6 months, or more frequently if symptoms arose. Microbiological evaluation was performed only in symptomatic women. All women were followed up for a mean of 38.8 months to analyze data from urine cultures and antibiograms. RESULTS: The previous study population consisted of 673 women, but 123 did not attend the entire follow-up period. For the final analysis, 257 of the remaining 550 patients were assigned to group A, and 293 to group B. At the end of follow-up, the difference in recurrence rates was statistically significant (P < .001): 97 (37.7%) in group A versus 204 (69.6%) in group B. Isolated Escherichia coli from group B showed higher resistance to amoxicillin-clavulanic acid (P = .03), trimethoprim-sulfamethoxazole (P = .01), and ciprofloxacin (P = .03) than that from group A. CONCLUSIONS: This study shows that AB treatment is associated with a higher occurrence of antibiotic-resistant bacteria, indicating that AB treatment in women with rUTIs is potentially dangerous.

Rising rates of carbapenem-resistant enterobacteriaceae in community hospitals: a mixed-methods review of epidemiology and microbiology practices in a network of community hospitals in the southeastern United States.

OBJECTIVE: Describe the epidemiology of carbapenem-resistant Enterobacteriaceae (CRE) and examine the effect of lower carbapenem breakpoints on CRE detection. DESIGN: Retrospective cohort. SETTING: Inpatient care at community hospitals. PATIENTS: All patients with CRE-positive cultures were included. METHODS: CRE isolated from 25 community hospitals were prospectively entered into a centralized database from January 2008 through December 2012. Microbiology laboratory practices were assessed using questionnaires. RESULTS: A total of 305 CRE isolates were detected at 16 hospitals (64%). Patients with CRE had symptomatic infection in 180 cases (59%) and asymptomatic colonization in the remainder (125 cases; 41%). Klebsiella pneumoniae (277 isolates; 91%) was the most prevalent species. The majority of cases were healthcare associated (288 cases; 94%). The rate of CRE detection increased more than fivefold from 2008 (0.26 cases per 100,000 patient-days) to 2012 (1.4 cases per 100,000 patient-days; incidence rate ratio (IRR), 5.3 [95% confidence interval (CI), 1.22-22.7]; P = .01). Only 5 hospitals (20%) had adopted the 2010 Clinical and Laboratory Standards Institute (CLSI) carbapenem breakpoints. The 5 hospitals that adopted the lower carbapenem breakpoints were more likely to detect CRE after implementation of breakpoints than before (4.1 vs 0.5 cases per 100,000 patient-days; P < .001; IRR, 8.1 [95% CI, 2.7-24.6]). Hospitals that implemented the lower carbapenem breakpoints were more likely to detect CRE than were hospitals that did not (3.3 vs 1.1 cases per 100,000 patient-days; P = .01). CONCLUSIONS: The rate of CRE detection increased fivefold in community hospitals in the southeastern United States from 2008 to 2012. Despite this, our estimates are likely underestimates of the true rate of CRE detection, given the low adoption of the carbapenem breakpoints recommended in the 2010 CLSI guidelines.

Asymptomatic Plasmodium falciparum infection is associated with anaemia in pregnancy and can be more cost-effectively detected by rapid diagnostic test than by microscopy in Kinshasa, Democratic Republic of the Congo.

BACKGROUND: In areas of high malaria transmission, Plasmodium falciparum infection during pregnancy is characterized by malaria-related anaemia, placental malaria and does not always result in clinical symptoms. This situation is associated with poor pregnancy outcomes. The aim of this study was to determine the extent of asymptomatic P. falciparum infection, its relation with anaemia as well as the most cost-effective technique for its diagnosis in healthy pregnant women living in Kinshasa, Democratic Republic of the Congo. METHODS: In a cross-sectional study design, information on socio-demographic characteristics and cost data were collected in healthy pregnant women attending antenatal care consultations. Plasmodium falciparum infection was diagnosed using rapid diagnostic test (RDT), microscopy and polymerase chain reaction (PCR). Haemoglobin concentration was also determined. RESULTS: In total, 332 pregnant women were enrolled. RDT and microscopy data were available for all the blood samples and 166 samples were analysed by PCR. The prevalence of asymptomatic P. falciparum infection using microscopy, RDTs and PCR, were respectively 21.6%, 27.4% and 29.5%. Taking PCR as a reference, RDTs had a sensitivity of 81.6% and a specificity of 94.9% to diagnose asymptomatic P. falciparum infection. The corresponding values for microscopy were 67.3% and 97.4%. The prevalence of anaemia was 61.1% and asymptomatic malaria increased five times the odds (p < 0.001) of having anaemia. RDTs were more cost-effective compared to microscopy. Incremental cost-effectiveness ratio was US$ 63.47 per microscopy adequately diagnosed case. CONCLUSION: These alarming results emphasize the need to actively diagnose and treat asymptomatic malaria infection during all antenatal care visits. Moreover, in DRC, malaria and anaemia control efforts should be strengthened by promoting the use of insecticide-treated nets, intermittent preventive treatment with sulphadoxine-pyrimethamine and iron and folic acid supplements.

Subclinical infection and asymptomatic carriage of gastrointestinal zoonoses: occupational exposure, environmental pathways, and the anonymous spread of disease.

Asymptomatic carriage of gastrointestinal zoonoses is more common in people whose profession involves them working directly with domesticated animals. Subclinical infections (defined as an infection in which symptoms are either asymptomatic or sufficiently mild to escape diagnosis) are important within a community as unknowing (asymptomatic) carriers of pathogens do not change their behaviour to prevent the spread of disease; therefore the public health significance of asymptomatic human excretion of zoonoses should not be underestimated. However, optimal strategies for managing diseases where asymptomatic carriage instigates further infection remain unresolved, and the impact on disease management is unclear. In this review we consider the environmental pathways associated with prolonged antigenic exposure and critically assess the significance of asymptomatic carriage in disease outbreaks. Although screening high-risk groups for occupationally acquired diseases would be logistically problematical, there may be an economic case for identifying and treating asymptomatic carriage if the costs of screening and treatment are less than the costs of identifying and treating those individuals infected by asymptomatic hosts.