SETTING: The country of Georgia has a high burden of multi- (MDR-TB) and extensively drug-resistant tuberculosis (XDR-TB). OBJECTIVE: To assess the performance of the Geno- Type® MTBDRsl assay in the detection of resistance to kanamycin (KM), capreomycin (CPM) and ofloxacin (OFX), and of XDR-TB.
DESIGN: Consecutive acid-fast bacilli smear-positive sputum specimens identified as MDR-TB using the MTBDRplus test were evaluated with the MTBDRsl assay and conventional second-line drug susceptibility testing (DST).
RESULTS: Among 159 specimens, amplification was adequate in 154 (97%), including 9 of 9 culture-negative and 2 of 3 contaminated specimens. Second-line DST revealed that 17 (12%) Mycobacterium tuberculosis isolates were XDR-TB. Compared to DST, the MTBDRsl had 41% sensitivity and 98% specificity in detecting XDR-TB and 81% sensitivity and 99% specificity in detecting OFX resistance. Sensitivity was low in detecting resistance to KM (29%) and CPM (57%), while specificity was respectively 99% and 94%. Median times from sputum collection to second-line DST and MTBDRsl results were 70-104 vs. 10 days.
CONCLUSION: Although the MTBDRsl assay had a rapid turnaround time, detection of second-line drug resistance was poor compared to DST. Further genetic mutations associated with resistance to second-line drugs should be included in the assay to improve test performance and clinical utility.
SETTING: Tuberculosis (TB) health care facilities throughout Georgia.
OBJECTIVE: To describe smoking behaviors among health care workers (HCWs) at TB facilities and determine HCWs' knowledge and beliefs regarding the impact of tobacco use on anti-tuberculosis treatment.DESIGN: Cross-sectional survey from May to December 2014 in Georgia. Adult HCWs (age 718 years) at TB facilities were eligible. We administered a 60-question anonymous survey about tobacco use and knowledge of the effect of smoking on anti-tuberculosis treatment.
RESULTS: Of the 431 HCWs at TB facilities who participated, 377 (87.5%) were female; the median age was 50 years (range 20-77). Overall, 59 (13.7%) HCWs were current smokers and 35 (8.1%) were past smokers.Prevalence of current smoking was more common among physicians than among nurses (18.6% vs.7.9%, P , 0.0001). Among HCWs, 115 (26.7%) believed smoking does not impact anti-tuberculosis treatment, and only 25.3% of physicians/nurses received formal training in smoking cessation approaches.Physicians who smoked were significantly more likely to believe that smoking does not impact anti-tuberculosis treatment than non-smoking physicians (aOR 5.11, 95%CI 1.46-17.90).
CONCLUSION: Additional education about the effect of smoking on TB treatment outcomes is needed for staff of TB health care facilities in Georgia. Nurses and physicians need more training about smoking cessation approaches for patients with TB.
S E T T I N G: Hawassa Prison, Southern Region of Ethiopia.
O B J E C T I V E: To determine the burden of pulmonary tuberculosis (TB) using active case finding among prisoners.
D E S I G N: In this cross-sectional study, prisoners were screened for TB using a symptom screen. Those with cough of 72 weeks had spot and morning sputum samples collected for acid-fast bacilli (AFB) smear microscopy and molecular diagnostic testing (Xpert w MTB/RIF).
R E S U LT S: Among 2068 prisoners, 372 (18%) had a positive cough screen. The median age of these 372 persons was 23 years, 97% were male and 63% were from urban areas. Among those with a positive symptom screen, 8 (2%) were AFB sputum smear-positive and 31 (8%) were Xpert-positive. The point prevalence of pulmonary TB at the prison was 1748 per 100 000 persons. In multivariate analysis, persons with cough .4 weeks were more likely to have TB (OR 3.34, 95%CI 1.54-7.23).
C O N C L U S I O N: A high prevalence of TB was detected among inmates at a large Ethiopian prison. Active case finding using a cough symptom screen in combination with Xpert had high utility, and has the potential to interrupt transmission of Mycobacterium tuberculosis in correctional facilities in low- and middle-income, high-burden countries.
Background: Plasmodium vivax infections in humans or in new world monkeys pose research challenges that necessitate the use of alternative model systems. Plasmodium cynomolgi is a closely related species that shares genetic and biological characteristics with P. vivax, including relapses. Here, the haematological dynamics and clinical presentation of sporozoite-initiated P. cynomolgi infections in Macaca mulatta (rhesus macaques) are evaluated over a 100-day period.
Methods: Five M. mulatta were inoculated with 2000 P. cynomolgi B strain sporozoites. Parasitological and haematological data were collected daily to study the clinical presentations of primary infections and relapses. Peripheral blood and bone marrow aspirates were collected at specific time points during infection for future and retrospective systems biology analyses.
Results: Patent infections were observed between days 10 and 12, and the acute, primary infection consisted of parasitaemias ranging from 269,962 to 1,214,842 parasites/µl (4.42–19.5 % parasitaemia). All animals presented with anaemia, ranging from moderate (7–10 g/dl) to severe (<7 g/dl), based on peripheral haemoglobin concentrations. Minimum haemoglobin levels coincided with the clearance of parasites and peripheral reticulocytosis was evident at this time. Mild thrombocytopaenia (<150,000 platelets/µl) was observed in all animals, but unlike haemoglobin, platelets were lowest whenever peripheral parasitaemia peaked. The animals’ conditions were classified as non-severe, severe or lethal (in one case) based upon their clinical presentation. The lethal phenotype presented uniquely with an exceptionally high parasitaemia (19.5 %) and lack of a modest reticulocyte release, which was observed in the other animals prior to acute manifestations. One or two relapses were observed in the four surviving animals, and these were characterized by significantly lower parasitaemias and minimal changes in clinical parameters compared to pre-infection values.
Conclusions: Rhesus macaque infections initiated by P. cynomolgi B strain sporozoites recapitulated pathology of human malaria, including anaemia and thrombocytopaenia, with inter-individual differences in disease severity. Importantly, this study provides an in-depth assessment of clinical and parasitological data, and shows that unlike the primary infections, the relapses did not cause clinical malaria. Notably, this body of research has provided experimental plans, large accessible datasets, and blood and bone marrow samples pertinent for ongoing and iterative systems biology investigations.
We describe the Centers for Disease Control and Prevention's National Nosocomial Infections Surveillance system. Elements of the system critical for successful reduction of nosocomial infection rates include voluntary participation and confidentiality; standard definitions and protocols; identification of populations at high risk; site-specific, risk-adjusted infection rates comparable across institutions; adequate numbers of trained infection control professionals; dissemination of data to health-care providers; and a link between monitored rates and prevention efforts.
Antimicrobial resistance is increasing in nearly all health-care-associated pathogens. We examined changes in resistance prevalence during 1996-1999 in 23 hospitals by using two statistical methods. When the traditional chi-square test of pooled mean resistance prevalence was used, most organisms appear to have increased in prevalence. However, when a more conservative test that accounts for changes within individual hospitals was used, significant increases in prevalence of resistance were consistently observed only for oxacillin-resistant Staphylococcus aureus, ciprofloxacin-resistant Pseudomonas aeruginosa, and ciprofloxacin- or ofloxacin-resistant Escherichia coli. These increases were significant only in isolates from patients outside intensive-care units (ICU). The increases seen are of concern; differences in factors present outside ICUs, such as excessive quinolone use or inadequate infection-control practices, may explain the observed trends.
Since their earliest days, humans have been struggling with infectious diseases. Caused by viruses, bacteria, protozoa, or even higher organisms like worms, these diseases depend critically on numerous intricate interactions between parasites and hosts, and while we have learned much about these interactions, many details are still obscure. It is evident that the combined host-parasite dynamics constitutes a complex system that involves components and processes at multiple scales of time, space, and biological organization. At one end of this hierarchy we know of individual molecules that play crucial roles for the survival of a parasite or for the response and survival of its host. At the other end, one realizes that the spread of infectious diseases by far exceeds specific locales and, due to today's easy travel of hosts carrying a multitude of organisms, can quickly reach global proportions. The community of mathematical modelers has been addressing specific aspects of infectious diseases for a long time. Most of these efforts have focused on one or two select scales of a multi-level disease and used quite different computational approaches. This restriction to a molecular, physiological, or epidemiological level was prudent, as it has produced solid pillars of a foundation from which it might eventually be possible to launch comprehensive, multi-scale modeling efforts that make full use of the recent advances in biology and, in particular, the various high-throughput methodologies accompanying the emerging -omics revolution. This special issue contains contributions from biologists and modelers, most of whom presented and discussed their work at the workshop From within Host Dynamics to the Epidemiology of Infectious Disease, which was held at the Mathematical Biosciences Institute at Ohio State University in April 2014. These contributions highlight some of the forays into a deeper understanding of the dynamics between parasites and their hosts, and the consequences of this dynamics for the spread and treatment of infectious diseases.
by
Richard Platt;
Ken Kleinman;
Kristin Thompson;
Rachel S. Dokholyan;
James M. Livingston;
Andrew Bergman;
John H. Mason;
Teresa C. Horan;
Robert Gaynes;
Steven L. Solomon;
Kenneth E. Sands
We determined if infection indicators were sufficiently consistent across health plans to allow comparison of hospitals' risks of infection after coronary artery bypass surgery. Three managed care organizations accounted for 90% of managed care in eastern Massachusetts, from October 1996 through March 1999. We searched their automated inpatient and outpatient claims and outpatient pharmacy dispensing files for indicator codes suggestive of postoperative surgical site infection. We reviewed full text medical records of patients with indicator codes to confirm infection status. We compared the hospital-specific proportions of cases with an indicator code, adjusting for health plan, age, sex, and chronic disease score. A total of 536 (27%) of 1,953 patients had infection indicators. Infection was confirmed in 79 (53%) of 149 reviewed records with adequate documentation. The proportion of patients with an indicator of infection varied significantly (p < 0.001) between hospitals (19% to 36%) and health plans (22% to 33%). The difference between hospitals persisted after adjustment for health plan and patients' age and sex. Similar relationships were observed when postoperative antibiotic information was ignored. Automated claims and pharmacy data from different health plans can be used together to allow inexpensive, routine monitoring of indicators of postoperative infection, with the goal of identifying institutions that can be further evaluated to determine if risks for infection can be reduced.
SETTING: A well-trained and sufficient tuberculosis (TB) workforce is essential for disease control, especially in an era of newly implemented diagnostics and medications. However, there are few reports on the status of the TB workforce in many endemic countries. OBJECTIVE: To evaluate the demographics, salary, career satisfaction, and attitudes towards the field of TB among the physician TB workforce in the country of Georgia.
DESIGN: A cross-sectional study of physicians in the current Georgian National TB Programme (NTP) using an anonymous 31-item questionnaire.
RESULTS: Among 184 NTP physicians countrywide, 142 (77%) were contacted and 138 (75%) completed questionnaires. The median age was 56 years (inter-quartile range 50-64); most (81%) were female. The monthly salary from TB work was ≤USD205 for 50% of respondents. Nearly half (47%) received an additional salary from another source. Many physicians (65%) indicated that they were satisfied with their work, but over half (55%) were unsatisfied with reimbursement. While most physicians (78%) were concerned about the lack of interest in TB, only 36% would recommend a career in TB care. CONCLUSION: While the current TB workforce in Georgia finds their work fulfilling, an ageing workforce, low salaries and perceived lack of interest in the field are a matter of concern for future TB control.
by
Samantha I Pitts;
Nisa M Maruthur;
Gayle E Langley;
Tracy Pondo;
Kathleen A Shutt;
Rosemary Hollick;
Stephanie J Schrag;
Ann Thomas;
Megin Nichols;
Monica Farley;
James P Watt;
Lisa Miller;
William Schaffner;
Corinne Holtzman;
Lee H Harrison
Background. Rates of invasive group B Streptococcus (GBS) disease, obesity, and diabetes have increased in US adults. We hypothesized that obesity would be independently associated with an increased risk of invasive GBS disease. Methods. We identified adults with invasive GBS disease within Active Bacterial Core surveillance during 2010-2012 and used population estimates from the Behavioral Risk Factor Surveillance System to calculate invasive GBS incidence rates. We estimated relative risks (RRs) of invasive GBS using Poisson analysis with offset denominators, with obesity categorized as class I/II (body mass index [BMI] = 30-39.9 kg/m2) and class III (BMI ≥ 40.0 kg/m2). Results. In multivariable analysis of 4281 cases, the adjusted RRs of invasive GBS disease were increased for obesity (class I/ II: RR, 1.52; 95% confidence interval [CI], 1.14-2.02; and class III: RR, 4.87; 95% CI, 3.50-6.77; reference overweight) and diabetes (RR, 6.04; 95% CI, 4.77-7.65). The adjusted RR associated with class III obesity was 3-fold among persons with diabetes (95% CI, 1.38-6.61) and nearly 9-fold among persons without diabetes (95% CI, 6.41-12.46), compared with overweight. The adjusted RRs associated with diabetes varied by age and BMI, with the highest RR in young populations without obesity. Population attributable risks of invasive GBS disease were 27.2% for obesity and 40.1% for diabetes. Conclusions. Obesity and diabetes were associated with substantially increased risk of infection from invasive GBS. Given the population attributable risks of obesity and diabetes, interventions that reduce the prevalence of these conditions would likely reduce the burden of invasive GBS infection.