Abuse and Neglect, COVID -19 Coronavirus, Infections / 10.06.2020

MedicalResearch.com Interview with: Edmond A. Hooker, MD, DrPH Professor, Department of Health Services Administration MHSA Associate Director for Accreditation Xavier University Cincinnati, Ohio  MedicalResearch.com: What is the background for this study? Response: Healthcare acquired infections are still a huge problem in the US. Most hospitals are not following the hospital bed manufacturers guidelines for cleaning these mattresses and bed decks (the metal bed frame). Many use only a single step, when the manufacturers recommend a 5-6 step process (pre-clean any obvious soil, clean, rinse off cleaner, disinfect, rinse off disinfectant, inspect mattress for damage). The problem is that, if done, this takes 45 minutes to 1 hours. Most hospitals turn over a hospital room in less than 30 minutes. The launderable bed cover allows the bed to be cleaned and turned over in minutes, not an hours.  (more…)
Author Interviews, C. difficile, Hospital Acquired / 08.01.2020

MedicalResearch.com Interview with: Alexandre R. Marra, MD PhD Iowa Infection Prevention Research Group University of Iowa Carver College of Medicine Division of Medical Practice, Hospital Israelita Albert Einstein São Paulo, Brazil MedicalResearch.com: What is the background for this study? Response: This is a comprehensive systematic literature review evaluating the burden of C. difficile infections in the U.S healthcare system. The literature has diverse studies with variable outcomes. Thus, we only included incidence estimates derived from multicenter studies. In our meta-analysis to calculate incidence, data were pooled only with denominators using the same unit (patient-days) to avoid comparisons with different denominators. For length of stay (LOS), we only included studies that used advanced statistical methods (e.g., propensity score matching). (more…)
Author Interviews, Hospital Acquired, JAMA / 20.08.2019

MedicalResearch.com Interview with: Todd Campbell Lee MD MPH FACP FIDSA Consultant in Internal Medicine and Infectious Diseases Director, MI4 Clinical Trials Platform Associate Professor of Medicine, McGill University Montreal, Quebec  MedicalResearch.com: What is the background for this study? Response: For a number of years people have been advocating for a move towards single-patient rooms in hospital design.  This was articulately argued for in an opinion piece by Detsky and Etchells in 2008 (https://jamanetwork.com/journals/jama/article-abstract/182433) as being important for a move to safe and patient-centered design. One of the major selling points has always been a reduction in the risk of nosocomial, or hospital-associated, infections given reduced opportunities for contamination between patients; however, only a few studies have specifically looked at this issue.  Overall, despite some strong work, many of these studies were limited by only looking at specific units, over limited periods of time,  and using before-after comparisons which did not account for change over time either within or outside of the institution. We knew that in 2015 our old hospital would close and within the same day all patients would be moved to a brand new hospital with 100% single patient rooms -- most of which have a private bathroom for patients and a separate hand-washing sink for staff.  So in 2014, we designed this study, obtained ethics review, and then waited patiently for several years to pass after the move so that we could rigorously evaluate the impact.  We looked at monthly rates of vancomycin-resistant Enterococcus (VRE) colonizations and infections, methicillin-resistant Staphylococcus aureus (MRSA) colonization and infections, and Clostridium (now Clostrideroidesdifficile infections (CDI). We chose these because we had good long term data on their rates and because we could compare the rates over time before and after the move and contrast them with the province of Quebec as a whole. (more…)
Author Interviews, Hospital Acquired, Infections, Merck / 16.04.2019

MedicalResearch.com Interview with: Elizabeth Rhee, MD Executive Director, Infectious Disease Clinical Research Merck Research Laboratories MedicalResearch.com: What is the background for this study? Would you briefly explain the condition of ventilated nosocomial pneumonias? Dr. Rhee: Nosocomial pneumonia (NP) is a lung infection that occurs during a hospital stay. NP is often serious, and is associated with high mortality. It is one of the most common health-care associated infections in both the U.S. and Europe, accounting for over 20% of such cases. Gram-negative bacteria, mainly Pseudomonas aeruginosa (PSA) and Enterobacteriaceae, are frequent causes of nosocomial pneumonia. Limited options currently exist for the management of NP caused by Gram-negative pathogens. This is concerning because rates of resistance to Gram-negative bacteria are growing, and they are becoming increasingly difficult to treat. Forms of nosocomial pneumonia include hospital-acquired pneumonia (HAP), ventilator-associated pneumonia (VAP), and ventilated HAP. High rates of death (ranging from 20% to more than 50%) are especially associated with ventilated HAP. Pseudomonas aeruginosa, a Gram-negative bacterium, is the most common cause of HAP/VAP in both the U.S. and Europe. Patients with NP are often critically ill, requiring ventilator support and time in intensive care, and it was important to look at this population as we explore new options for the treatment of NP. Ceftolozane/tazobactam (C/T) is an antipseudomonal cephalosporin/beta-lactamase inhibitor combination with broad in vitro activity against Gram-negative pathogens, including multi-drug resistant (MDR) P. aeruginosa and many extended-spectrum beta-lactamase (ESBL) producers. It is FDA approved for complicated intra-abdominal and urinary tract infections in adults at 1.5g (1g ceftolozane/0.5g tazobactam) q8h. C/T is currently being studied at an investigational new dose of 3g (2g/1g) q8h, for the treatment of ventilated nosocomial pneumonia, in the ASPECT-NP Phase 3 trial. (more…)
Author Interviews, Cost of Health Care, Critical Care - Intensive Care - ICUs, Health Care Systems, Hospital Acquired, JAMA, Urinary Tract Infections / 06.02.2019

MedicalResearch.com Interview with: Heather Hsu, MD MPH Assistant Professor of Pediatrics Boston University School of Medicine Boston Medical Center Boston, MA 02118 MedicalResearch.com: What is the background for this study? What are the main findings?  Response: In October 2013, the Centers for Medicare and Medicaid Services (CMS) implemented value-based incentive programs to financially reward or penalize hospitals based on quality metrics. Two of these programs – Hospital Value Based Purchasing and the Hospital Acquired Condition Reduction Program – began targeting hospitals’ rates of certain healthcare-associated infections deemed to be preventable in October 2015. Previous studies demonstrated minimal impact of these value-based payment programs on other measures of hospital processes, patient experience, and mortality. However, their impact on healthcare-associated infections was unknown. Our goal was to study the association of value-based incentive program implementation with healthcare-associated infection rates, using catheter-associated urinary tract infection in intensive care units (one of the targeted outcomes) as an example. We found no evidence that federal value-based incentive programs had any measurable association with changes in catheter-associated urinary tract infection rates in the critical care units of US hospitals. (more…)
Author Interviews, Hospital Acquired, Infections, Technology / 23.01.2019

MedicalResearch.com Interview with: Donna Armellino RN, DNP, CIC Vice President, Infection Prevention Northwell Health, Infection Prevention Lake Success, N. Y. MedicalResearch.com: What is the background for this study?  Response: The background for initiating this study was to assess frequently used equipment within the patient care environment following standard manual cleaning and disinfection compared to disinfection with PurpleSun’s shadowless 90-second cycle focused multivector ultraviolet (FMUV) delivery system. Microbes exist within the environment. Cleaning followed by disinfection, regardless of method, is intended to decrease levels of these microbes to minimize exposure and the risk of infection. To measure the effectiveness of the two methods of disinfection a five-point culturing method was used to assess microbial burden. This method was used to assess patient care equipment cleanliness after manual cleaning/disinfection and following the use of FMUV after an operative case and was used to sample equipment deemed cleaned/disinfected and ready for use outside the operative environment. Microbial burden was reported as colony forming units (CFUs). Comparison of the CFUs before cleaning/disinfection, after cleaning/disinfection, and after the use of FMUV allowed efficacy of the disinfection methods to be compared.  (more…)
Author Interviews, CDC, Hospital Acquired / 01.11.2018

MedicalResearch.com Interview with: "Hospital Room" by Kyle Taylor is licensed under CC BY 2.0Dr. Shelley Magill, MD Medical Officer and CDC lead for the hospital HAI (hospital acquired infections) and antimicrobial use prevalence survey MedicalResearch.com: What is the background for this study? Response: The prevalence survey effort began in 2009. The goal was to obtain a snapshot of all healthcare-associated infections affecting hospital patients, not limited to those commonly reported to the National Healthcare Safety Network. We conducted our first full-scale hospital prevalence survey in 2011, in collaboration with the Emerging Infections Program, a network of 10 state health departments and academic and other partners. Data from that survey showed that about four percent of patients had a healthcare-associated infection—or, on any given day, about 1 in 25 patients. We repeated the survey in a similar group of hospitals in 2015 to see whether changes had occurred. (more…)
Author Interviews / 06.10.2018

MedicalResearch.com Interview with: MedicalResearch.com Interview with: Gili Regev-Yochay, MD, Lead author Director of the Infection Prevention & Control Unit Sheba Medical Center Tel HaShomer, Israel.   MedicalResearch.com: What is the background for this study?  Response: CPE (Carbapenemase producing Enterobacteriaceae) is endemic in Israel. In our ICU we had a prolonged CPE outbreak with one particular bacteria, which is not that common (OXA-48 producing-Serratia marcescens).  Enhancing our regular control measures (hand hygiene, increased cleaning etc..) did not contain the outbreak.    MedicalResearch.com: What are the main findings?   Response: The outbreak source were the sink-traps in nearly all the patient rooms, which were contaminated with this same bacteria. Once we understood that this was the source we took two measures:  1) Sink decontamination efforts, including intensive chlorine washes of the drainage and water system, replacement of all sink-traps, acetic acid treatment and more, all these efforts were only partially and only temporarily successful. So that even today, after a year of such efforts and a period in which we didn't have any patients with this infection, the drainage system is still contaminated with these bugs and they grow in the sink-traps and can be found in the sink outlets.  2) The second measure we took was an educational intervention, where we engaged the ICU team through workshops to the issue of the contaminated sinks and together enforced strict "sink-use guidelines" (sinks are to be used ONLY for hand washing, prohibiting placement of any materials near the sinks, etc.). Using these two measure the outbreak was fully contained.  To date, nearly 1.5 years since the last outbreak case, we did not have any further infections in our ICU patients with this bug.  MedicalResearch.com: What should readers take away from your report?  Response: Sink-traps and drainage systems can be a major source of CPE transmission.  While traditionally CPE outbreaks were attributed to patient-to patient transmission, the environment and particularly water and drainage system appears to play a major role.  MedicalResearch.com: What recommendations do you have for future research as a result of this work?   Response: There is urgent need to find a technological solution for drainage system contaminations.  While some have suggested to get rid of sinks in ICU this is probably not realistic in the era of emerging Clostridium infections (where washing hands, and not only alcohol rubs are needed).   Citation:  Gili Regev-Yochay, Gill Smollan, Ilana Tal, Nani Pinas Zade, Yael Haviv, Valery Nudelman, Ohad Gal-Mor, Hanaa Jaber, Eyal Zimlichman, Nati Keller, Galia Rahav. Sink traps as the source of transmission of OXA-48–producing Serratia marcescens in an intensive care unit. Infection Control & Hospital Epidemiology, 2018; 1 DOI: 1017/ice.2018.235  [wysija_form id="3"]  [last-modified]          The information on MedicalResearch.com is provided for educational purposes only, and is in no way intended to diagnose, cure, or treat any medical or other condition. Always seek the advice of your physician or other qualified health and ask your doctor any questions you may have regarding a medical condition. In addition to all other limitations and disclaimers in this agreement, service provider and its third party providers disclaim any liability or loss in connection with the content provided on this website.   Gili Regev-Yochay, MD, Lead author Director of the Infection Prevention & Control Unit Sheba Medical Center Tel HaShomer, Israel.  MedicalResearch.com: What is the background for this study? Response: CPE (Carbapenemase producing Enterobacteriaceae) is endemic in Israel. In our ICU we had a prolonged CPE outbreak with one particular bacteria, which is not that common (OXA-48 producing-Serratia marcescens).  Enhancing our regular control measures (hand hygiene, increased cleaning etc..) did not contain the outbreak. (more…)
Author Interviews, Infections / 10.07.2018

MedicalResearch.com Interview with: Thomas A Russo, MD, CM The Departments of Medicine, and Microbiology and Immunology The Witebsky Center for Microbial Pathogenesis University at Buffalo-State University of New York, and the Veterans Administration Western New York Healthcare System Buffalo, New York MedicalResearch.com: What is the background for this study? What is Klebsiella pneumoniae? Response: K. pneumoniae is an important bacterial pathogen that cause a number of different infections. Presently, two pathotypes exist that behave very differently. Classical K. pneumoniae, which is most common in North America and Europe primarily causes infections in the healthcare setting, usually in patients with co-morbidities. Also, it is becoming increasingly antimicrobial resistant, making treatment challenging. Hypervirulent K. pneumoniae, which is more common in the Asian Pacific Rim,  can cause infections in otherwise healthy individuals, often causes infection in multiple sites, and these sites are usually not infected by classical K. pneumonia, such as the eye, brain, and aggressive soft-tissue infection (necrotizing fasciitis). Hypervirulent K. pneumonia strains are also becoming antimicrobial resistant, albeit at a slower rate than classical K. pneumoniae at this time. There are some differences how infections due to these two pathotypes are managed. It would also be ideal to track the prevalence and relative antimicrobial resistance of these two pathotypes, but up until now this could not be reliably done because there was not a validated test that could differentiate them. The goal of this study was to identify biomarkers that could accurately differentiate classical from hypervirulent K. pneumoniae.  (more…)
Author Interviews, Cost of Health Care, Hospital Acquired, Medicare / 02.07.2018

MedicalResearch.com Interview with: Michael S. Calderwood, MD, MPH, FIDSA Regional Hospital Epidemiologist Assistant Professor of Medicine Infectious Disease & International Health MedicalResearch.com: What is the background for this study?   Response: Prior work by Lee et al. (N Engl J Med 2012;367:1428–1437) found that the 2008 CMS Hospital-Acquired Conditions (HAC) policy did not impact already declining national rates of central line-associated bloodstream infections (CLABSIs) or catheter-associated urinary tract infections (CAUTIs). We studied why this policy did not have its intended impact by looking at coding practices and the impact of the policy on the diagnosis-related group (DRG) assignment for Medicare hospitalizations. The DRG assignment determines reimbursement for inpatient hospitalizations. (more…)
Author Interviews, Hospital Acquired / 09.11.2016

MedicalResearch.com Interview with: Dusty Deringer Vice president of Patient Experience for Crothall Healthcare Compass One Healthcare MedicalResearch.com: What are the main findings from your new research? Response: Patients’ perceptions of a hospital’s cleanliness can have a major impact on their overall care and hospital experience. Specifically, the data show correlations between patients’ perceptions of room cleanliness and three important categories: the risk of hospital-acquired infections; a hospital’s score on the Hospital Consumer Assessment of Healthcare Providers and Systems (HCAHPS) survey and scores on the HCAHPS teamwork indicators. The findings are important because patients are more likely to recommend a hospital they perceive to be clean. Therefore, it makes cleanliness a target for improvement for all hospitals. (more…)
Author Interviews, C. difficile, Columbia, Hospital Acquired, JAMA / 12.10.2016

MedicalResearch.com Interview with: Dr. Daniel E. Freedberg MD MS Division of Digestive and Liver Diseases Columbia University Medical Center New York, New York MedicalResearch.com: What is the background for this study? Response: We conducted this study because previous studies indicate that the gastrointestinal microbiome is easily shared between people who co-occupy a given space (such as a hospital room).  We wondered if antibiotics might exert an effect on the local microbial environment. (more…)
Author Interviews, Infections, Outcomes & Safety, Pediatrics / 29.08.2016

MedicalResearch.com Interview with: Dr. Cohen Regev, M.D Head of the infectious diseases and infection control units Sanz Medical Center, Laniado hospital Netanya, Israel MedicalResearch.com: What is the background for this study? Response: During 3 months in 2012 we had a number of clinical isolates of Pseudomonas aeruginosa (PA) in our neonatal intensive care unit (NICU) and a high incidence of colonization among ventilated patients in our medical-surgical intensive care unit (MSICU). The origin of PA may be from various environmental sources (‘exogenous’), from the patients’ own microbiome (‘endogenous’), or from both. Since in NICUs the origin is usually exogenous, we investigated the sources of the bacteria, focusing on the faucets of these units, as they were previously incriminated as causes of outbreaks in ICUs. The study was conducted in Sanz medical center, a 400-bed community hospital located in central Israel. In the NICU we obtained several environmental cultures from faucets using a bacterial swab by rubbing the tip into the distal part of the faucet. Aerators were dismantled from all faucets, cultured from their inner part using a swab and were not repositioned. Contaminated faucets were occasionally replaced or treated with enzymatic fluid and sterilization by Ethylene Oxide. During the intervention and since, neonates were bathed only with warmed sterile water, and tap water was allowed only for hand hygiene practices. In the MSICU tap water was used only for bathing the patients. All other uses of tap water, such as drinking, moistening and mouth treatments, were allowed using only sterile water. The units' faucets were sampled on two different days concurrently with surveillance cultures of pharyngeal, sputum and urine from the patients. Bacteria were identified with VITEK 2 (Biomerieux®) and typing was done by Enterobacterial Repetitive Intergenic Consensus (ERIC) PCR. (more…)
Author Interviews, Hospital Acquired, Outcomes & Safety / 12.02.2016

MedicalResearch.com Interview with: Christine Greene, Ph.D. and Chuanwu Xi, Ph.D. School of Public Health, Department of Environmental Health Sciences University of Michigan Medical Research: What is the background for this study? Response: Healthcare-associated infections (HAIs) are a serious problem globally.  Acinetobacter baumannii, a gram-negative opportunistic pathogen, was mostly unheard of 10-15 years ago, but is now a clinically significant pathogen in hospitals.  A. baumannii causes a variety of infections ranging from urinary tract infections to bacteremia and patients who are at high risk of A. baumannii infection are those who are critically ill, who have indwelling catheters or patients with long hospital says.  Once infected, the risk of mortality is high – up to 26% for in-hospital patients and as much as 43% for those in the ICU.  The mortality rate is high largely due to the rapid ability for this pathogen to develop antibiotic resistance.  Despite patient isolation, we still see hospital outbreaks because A. baumannii survives very well in the environment and it is resistant to most biocides, detergents, dehydration, and UV radiation.  A. baumannii is also a known biofilm former.  Biofilms serve to protect the microorganism.  In the open environment, biofilms protect from desiccation and other harsh environmental insults such as biocides, thereby promoting persistence in the open environment.  In the human body, biofilms protect against the immune system, provide an additional layer of protection from antibiotics and contribute to reoccurring infections in the patient. This research characterizes the fitness (desiccation tolerance) trade-offs imposed on A. baumannii isolated from clinical and environmental settings.  This investigation compares isolates of A. baumannii from both environments on the basis of multidrug resistance, biofilms and desiccation tolerance.  We looked to see if either MDR or biofilm formation increased fitness (ability to tolerate desiccation) or impose a fitness cost depending on environmental conditions. Medical Research: What are the main findings? Response: We provide evidence of variation in desiccation tolerance between clinical and environmental isolates of similar phenotypes and show a trend of increased desiccation tolerance for high biofilm forming clinical isolates with additional tolerance when the ability to form biofilms is coupled with the multidrug resistance.  By contrast, biofilm formation had a significant impact on desiccation tolerance for environmental isolates.


Author Interviews, C. difficile, Infections / 30.07.2015

Dr. Monika Pogorzelska-Maziarz PhD MPH Thomas Jefferson University, Jefferson School of Nursing Philadelphia, PA 19107MedicalResearch.com Interview with: Dr. Monika Pogorzelska-Maziarz PhD MPH Thomas Jefferson University, Jefferson School of Nursing Philadelphia, PA 19107 Medical Research: What is the background for this study? What are the main findings? Dr. Pogorzelska-Maziarz: Sharps disposal containers are ubiquitous in healthcare facilities and there is a growing trend toward hospitals using reusable sharps containers. Several research studies have raised concerns about the potential for sharps containers to become a source of pathogen transmission within the healthcare setting but this issue that has not been systematically studied. This is an important issue given that contamination of the hospital environment has been shown to be an important component of pathogen transmission. To examine whether the use of reusable versus single use sharps containers was associated with rates of Clostridium difficile, we conducted a cross-sectional study of acute care hospitals. Survey data on the different types of sharps containers used were collected from over 600 hospitals and this data was linked to the Medicare Provider Analysis and Review (MedPAR) dataset, which contains facility characteristics and C. diff infections data. We found that hospitals using single-use containers had significantly lower rates of C. diff versus hospitals using reusable containers after controlling for hospital characteristics such as geographic region, teaching status, ownership type, hospital size and urbanicity. This is an important finding giving the ubiquitous nature of sharps containers in the health care setting, the growing trend toward hospitals using reusable sharps containers and the high burden of C. diff in the hospital setting. (more…)
Author Interviews, Hospital Acquired, JAMA / 13.01.2015

Teresa Waters PhD Professor and Chair, Preventive Medicine University of Tennessee Health Science Center Memphis TNMedicalResearch.com Interview with: Teresa Waters PhD Professor and Chair, Preventive Medicine University of Tennessee Health Science Center Memphis TN Medical Research: What is the background for this study? What are the main findings? Dr. Waters: On October 1, 2008, Medicare implemented the Hospital-Acquired Conditions (HACs) Initiative, a policy penalizing hospitals for eight complications of hospital care, also known as never events. Under the HACs Initiative, hospitals could no longer justify a higher level Medicare MS-DRG when caring for a patient who developed 1 of the 8 never events. This Initiative was one in a series of CMS payment reforms intended to increase emphasis on value-based purchasing. We found that Medicare's nonpayment policy was associated with significant improvements in the time trends for central line associated blood stream infections (CLABSIs) and catheter associated urinary tract infections(CAUTIs). For these outcomes, our data from the National Database of Nursing Quality Indicators showed that introduction of the Medicare policy was associated with an 11% reduction in the rate of change in central line associated blood stream infections and a 10% reduction in the rate of change in CAUTIs. We did not find any relationship between introduction of the policy and significant changes in injurious falls or hospital acquired pressure ulcers (two other important never events covered by the policy). We hypothesized that the Hospital-Acquired Conditions Initiative may have a great effect for conditions where there is strong evidence that better hospital processes yield better outcomes or where processes are more conducive to standardization. (more…)
Author Interviews, CDC, Hand Washing, Hospital Acquired, Infections, NEJM / 26.03.2014

MedicalResearch.com Interview with: Shelley S. Magill, M.D., Ph.D. From the Centers for Disease Control and Prevention Emory University School of Medicine Atlanta, Georgia MedicalResearch.com: What are the main findings of the study? Dr. Magill: The results of this survey show that healthcare-associated infections continue to be a threat to patient safety in U.S. acute care hospitals. Among the more than 11,000 patients included in the survey, approximately 4% (or 1 in 25) had at least one healthcare-associated infection at the time of the survey. We used these results to develop national estimates of healthcare-associated infections. We estimated that in 2011, there were approximately 721,800 healthcare-associated infections in U.S. acute care hospitals. The most common types of infections were surgical site infections (SSIs), pneumonias, and gastrointestinal infections. (more…)
Author Interviews, C. difficile, Infections, NEJM / 26.09.2013

MedicalResearch.com Interview with: David W. Eyre, B.M., B.Ch. Nuffield Department of Clinical Medicine University of Oxford National Institute for Health Research (NIHR) Oxford Biomedical Research Centre John Radcliffe Hospital MedicalResearch.com: What are the main findings of this study? Dr. Eyre: All cases of Clostridium difficile in Oxfordshire were studied over 3 years. Isolates were characterized by whole genome sequencing and the data was linked to hospital databases allowing epidemiological relationships between patients at the level of the hospital ward, hospital specialty, and post code to be identified. For comparison, similar information was also available for all other patients with and without diarrhea.  Preliminary work on the genetic diversity of Clostridium difficile within individuals and between individuals within discrete outbreaks allowed reliable interpretation of transmission events using genomic data. This allowed a complete reconstruction of the pattern of transmission between affected cases in Oxfordshire to be made. The findings were: 1. Unexpectedly few cases (13%) appear to be acquired from direct ward based contact with other symptomatic cases (these have previously been thought to be the main source of infections, and the focus of prevention efforts). Another 6% were associated with other hospital contact and 3% had plausible community contacts. 2. In 13% of cases potential donors were identified gnomically but no contact, within hospitals or the community, were identified. This suggests that the existence of other modes of transmission of Clostridium difficile. 3. The sources of Clostridium difficile infections were highly genetically diverse, with 45% of cases having a genetically distinct origin - suggesting a diverse reservoir of disease, not previously appreciated 4. During the 3 years of the study the rate of Clostridium difficile in Oxfordshire fell.  Any improvement in infection control techniques would be expected to reduce the incidence of cases caused by within hospital transmission. Surprisingly, similar rates of fall occurred in both in secondary cases (considered to be acquired from hospital associated symptomatic cases) and for primary cases (cases not associated with transmission from symptomatic cases). (more…)