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PubMed2004

Scabies by Kenneth Mellanby.

BACKGROUND: Epidemics of scabies are often associated with wars or other times of social upheaval. This was particularly evident during the Second World War when it was estimated that there were one to two million patients with scabies in Great Britain. OBJECTIVE: This article reviews the work of the zoologist Kenneth Mellanby of England and evaluates his contribution to our knowledge of the diagnosis and treatment of scabies in the Second World War. CONCLUSION: Using humans, Mellanby studied the transmission and treatment of this disease. Among his contributions were knowledge of how many mites the average patient had, and where they were located. He clearly noted and described that the scabies rash was not limited to the location of the mites on the body; he attributed the rash in areas with no mites to "a true sensitization." He found that "fomites were not the major method of transmissions.

England↗
PubMed1992

Management and epidemiologic analyses of an outbreak due to methicillin-resistant Staphylococcus aureus.

PURPOSE: Following implementation of special measures to control a nosocomial outbreak of methicillin-resistant Staphylococcus aureus (MRSA), we used immunoblot typing in conjunction with antimicrobial susceptibility testing to investigate the epidemiology of this event and to determine whether this outbreak represented the failure of infection control measures to limit the spread of previously endemic MRSA strains or the introduction of a new strain of MRSA. MATERIALS AND METHODS: Isolates of MRSA recovered from hospitalized patients were initially categorized on the basis of antimicrobial susceptibility results. Organisms susceptible to ciprofloxacin and/or trimethoprim/sulfamethoxazole were recovered from patients at a relatively constant rate prior to December 1988 and were categorized as endemic isolates. Subsequently, there was an outbreak due to organisms resistant to both of these antibiotics; these were therefore categorized as outbreak isolates. Isolates were later characterized by immunoblot typing. Prior to this analysis, isolates were given code numbers so that clinical and epidemiologic data as well as resistance patterns were not known until this testing was complete. RESULTS: Between January 1986 and November 1988, an average of 3.9 patients per month acquired nosocomial MRSA in the Sepulveda Veterans Administration Medical Center. In contrast, from December 1988 to October 1989, 369 MRSA isolates were collected from 125 patients (an average of 11.4 patients per month). Prior to December 1988, all tested nosocomial isolates of MRSA were susceptible to ciprofloxacin and/or to trimethoprim/sulfamethoxazole. In contrast, the outbreak was due to spread of MRSA isolates resistant to these antibiotics. Immunoblot typing of 204 isolates from 98 individuals identified five distinct immunoblot types of which types B and C were by far the most common. Type B was highly associated with outbreak isolates, whereas type C was associated with endemic isolates (p less than 0.001). All sequential isolates from single patients that belonged to different susceptibility categories demonstrated discordant immunoblot types. In contrast, concordant immunoblot types were observed for 25 of 27 sequential isolates that displayed minor variations in antimicrobial resistance. The institution of more stringent infection control measures was followed by the return of nosocomial MRSA acquisition rates to pre-outbreak levels. Although novobiocin and trimethoprim/sulfamethoxazole were extensively used to treat patients harboring outbreak and endemic isolates, respectively, in no instance was the initial MRSA isolate from any patient resistant to novobiocin and only 6% of initial endemic isolates displayed trimethoprim/sulfamethoxazole resistance. A modest, significant increase in the resistance of endemic isolates to various other antimicrobial agents was noted however. CONCLUSION: Immunoblot analyses provided strong, corroborative evidence that at least two separate strains of MRSA were present during the outbreak and that a newly introduced strain with a distinctive antimicrobial resistance pattern was primarily responsible for the rapid spread of MRSA during the outbreak. The observation that previously effective infection control measures failed to prevent the nosocomial spread of a newly introduced community-acquired MRSA strain suggests that a single set of control measures may not be equally efficacious against all strains of MRSA. In this regard, previously reported variations in resistance to topical antimicrobials and/or antiseptics, and differences in virulence factors such as colonization potential, invasiveness, and survival on fomites, may warrant further study. Control of the outbreak strain of MRSA in our institution did occur after the implementation of more strenuous isolation procedures.(ABSTRACT TRUNCATED)

California↗
PubMed1986

Upgrading sterilization in the orthodontic practice.

In today's orthodontic practice, disease control must undergo major reevaluation and restructuring. The knowledge of the natural history and treatment of many highly transmissible diseases to which orthodontic personnel are at high risk is changing rapidly. Among these diseases are acquired immune deficiency syndrome (AIDS), hepatitis B virus, and the herpesvirus complex (currently five types). If barrier techniques are not in place, it is possible to cross-infect orthodontic personnel and patients alike. Clinical orthodontics, with its higher volume of patients (on a daily basis) than other dental practices, requires a custom-made sterilization schema tailored to each office. Proper organization of instruments to permit orderly processing, storing, and use is even more important than before. Turnaround time of processing instruments, corrosion control, and minimizing of dulling of cutting edges are critical. Treatment of surfaces and chair/unit facilities with improved disinfection techniques is a necessity. Protection of hands and eyes by appropriate means is discussed with practical guidelines for the use of gloves by chairside personnel. Many fomites (inanimate disease transmitters) lurk in the orthodontic office and must be eliminated. Finally, the most important ingredient to any change--the orthodontic office staff--must be enlightened, trained, and supervised by the orthodontist to effectively and efficiently switch from the old to the new.

Communicable Disease Control↗
PubMed1992

Association of Ebola-related Reston virus particles and antigen with tissue lesions of monkeys imported to the United States.

During 1989-1990, an epizootic involving a filovirus closely related to Ebola virus occurred in a Reston, Virginia, primate-holding facility. Tissues were collected from cynomolgus monkeys and examined by electron microscopy and immunohistochemistry for Ebola-related viral antigen. Viral replication was extensive in fixed tissue macrophages, interstitial fibroblasts of many organs, circulating macrophages and monocytes, and was observed less frequently in vascular endothelial cells, hepatocytes, adrenal cortical cells and renal tubular epithelium. Viral replication was observed infrequently in epithelial cells lining ducts or mucous membranes, intestinal epithelial cells, eosinophils and plasma cells. Replication of Reston virus in lymphocytes was never observed, in contrast to reports of lymphocytes of monkeys experimentally infected with the Ebola-Zaire virus. Free filoviral particles were seen in pulmonary alveoli and renal tubular lumina, which correlates with epidemiological evidence of droplet and fomite transmission. Viral infection of interstitial fibroblasts and macrophages caused multisystemic disruptive lesions involving connective tissue. Focal necrosis in organs where viral replication was minimal may have been secondary to ischaemia caused by fibrin deposition and occasional platelet-fibrin thrombi. Immunoelectron microscopy on sections of liver, differentiated viral tubular inclusion masses and precursor material from non-viral tubuloreticular inclusions. Immunohistochemistry showed that the distribution of viral antigen in affected tissue correlated well with ultrastructural localization of virions.

Animals↗
PubMed1996

Detection of airborne cytomegalovirus in hospital rooms of immunocompromised patients.

Human cytomegalovirus (CMV) is a major pathogen in immunocompromised patients. Transmission in this population is known to occur by fomites, but the potential for airborne spread is unknown. In this study, air from the rooms of two immunosuppressed patients with CMV pneumonia and one patient with latent infection was filtered and examined by a polymerase chain reaction assay. CMV-DNA was easily detected in the rooms of the patients with pneumonia and a weak positive signal was detected in the room of the patient with latent CMV infection. This technique permits the detection of aerosolized CMV-DNA and could possibly be adapted to detect other airborne pathogens.

AIDS-Related Opportunistic Infections↗
PubMed1990

The survival of Acinetobacter calcoaceticus inoculated on fingertips and on formica.

When inoculated on the fingers of three volunteers, strains of Acinetobacter calcoaceticus var. anitratus survived better than strains of var. lwoffii; 60 min after an inoculum of 10(4) cfu/finger, washings yielded between 2.6 x 10(1) (for a sporadic strain of var. lwoffii) and 7.2 x 10(2) cfu/finger (for an epidemic strain of var. anitratus). All five test strains survived better on formica than on skin, and from an inoculum of 10(4) cfu, between 6.4 x 10(2) and 2.2 x 10(3) cfu/finger were recoverable 60 min later. After inoculation of formica sheets, both strains of var. lwoffii could still be recovered in low numbers 24 h later, and two of the three strains of var. anitratus 60 h later. These findings suggest the presence of hitherto unrecognized antibacterial activity of skin against Acinetobacter calcoaceticus and suggest that outbreaks may be sustained by hand transmission. The ability of these organisms to survive desiccation on formica supports the proposal that transmission by air, dust or fomites may hitherto have been underestimated for this species.

Acinetobacter↗
PubMed1986

Review of Clostridium difficile-associated diseases.

Clostridium difficile has recently become recognized as an important nosocomial pathogen. This review summarizes what is known about the isolation of the organism, the spectrum of clinical disease, virulence factors, treatments, and methods of prevention. Risk factors for C. difficile disease are also discussed. The most important risk factor is the use of certain antibiotics (ampicillin, cephalosporins, and clindamycin). C. difficile is associated with 96% to 100% of cases of pseudomembraneous colitis, 60% to 75% of antibiotic-associated cases of colitis, and 11% to 33% of antibiotic-associated cases of diarrhea. Other risk factors include gastrointestinal manipulations, advanced age, female sex, inflammatory bowel disease, cancer chemotherapy, and renal disorders. Hospital outbreaks of C. difficile disease are examined. Data from nosocomial outbreaks support transmission of C. difficile by contaminated fomites and hand carriage by hospital personnel.

Age Factors↗
PubMed1990

Survival and disinfection of parainfluenza viruses on environmental surfaces.

Three dilutions of each of three parainfluenza strains were placed on nonabsorptive (stainless steel, laminated plastic, skin) and absorptive (hospital gown, facial tissue, laboratory coat) surfaces to assess persistence of virus recovery at 0, 0.5, 1, 2, 4, 6, 8, and 10 hours. Virus persisted longest on stainless steel. Additionally, the ability to recover virus was enhanced by increasing the initial concentration of virus in the initial inoculum. Drying of the inoculum on surfaces reduced but did not immediately eliminate the ability to recover virus. Cleaning the contaminated surface with a number of commonly available disinfectant or antiseptic agents reduced or eliminated virus with only short exposure times. It is likely that removal of contaminated material by vigorous cleaning was as important as the actual disinfecting substance. In general, all three strains of parainfluenza virus responded similarly. Persistence of all three strains of parainfluenza virus for up to 10 hours on nonabsorptive surfaces and up to 4 hours on absorptive surfaces suggests a need to consider fomites a possible source of transmission of the parainfluenza viruses inside and outside the hospital.

Clothing↗
PubMed1995

Targeting ticks for control of selected hemoparasitic diseases of cattle.

Development in and transmission of hemoparasites by tick vectors are phenomena closely synchronized with the tick feeding cycle. In all known life cycles, initial infection of tick tissues occurs in midgut epithelial cells and transmission is effected as ticks feed after parasites have developed and multiplied in salivary glands. Many factors reviewed affect development and transmission of hemoparasites by ticks including age of ticks, artificial temperature, climate and/or season, tick stage or sex, hemoparasite variation, concurrent infection of ticks with other pathogens, host cell susceptibility, transovarial transmission, effect of hemoparasites on tick biology, and the effect of infecting parasitemia level in cattle on infection rates in ticks. Four hemoparasites of cattle, Anaplasma marginale, Cowdria ruminantium, Theileria parva, and Babesia spp., are all dependent on ticks for biological transmission. Babesia is transmitted transovarially whereas the other three are transmitted transstadially. Mechanical transfer of infective blood via fomites and mouthparts of biting arthropods is also a major means of transmission for Anaplasma marginale but not of the others. Potential control methods for hemoparasites that target parasites as they are developing in their respective tick hosts include tick control, vaccines (against ticks and parasites), and drugs (against ticks and parasites). Successful application of control strategies will be dependent upon thorough understanding of parasite developmental cycles, biology of the tick vectors and the immune response of cattle to ticks and to hemoparasites. The most effective control measures will be those that are targeted against both ticks and the hemoparasites they vector.

Animals↗
PubMed1994

The epidemiology of Mycobacterium bovis infections.

Mycobacterium bovis has an exceptionally wide host range, but until recent years there was little concern about infection in species other than cattle and man. Diversification of farming enterprises has led to cognizance of the need for control in other domestic animals, notably deer. There has also been recognition that self-maintaining infection is present in wildlife hosts in some countries--notably the European badger in the United Kingdom and Ireland, the Australian brush-tailed possum in New Zealand, and various species of ungulates in limited areas of a number of countries. Although transmission of M. bovis can occur by a number of different routes, control measures imposed on cattle and to a lesser extent on other species have reduced a number of the routes to insignificance. Hence the vast preponderance of transmission within host species is now by the airborne route, and predominantly between species as well. Transmission of infection from badgers to cattle may be an exception, with evidence remaining equivocal about the relative importance of pasture contamination by excretion in badger urine and airborne transmission. In general, contamination of feed and pasture appears to be unimportant in transmission of the disease, because survival times of infective doses of organisms on fomites are relatively short under realistic conditions and because animals are not commonly exposed to a dose high enough to be infective by the alimentary route. Infection through the oro-pharyngeal mucous membrane may be significant, although the infective dose for this route is not known. While many species of animals can become infected with M. bovis, only a few act as maintenance hosts and the rest are spillover hosts in which infection is not self-maintaining. With the exception of cattle and deer, other species have become maintenance hosts only within part of their ecological range. For both badgers and possums, maintenance of infection within a local population is due to pseudo-vertical transmission from mother to young, and horizontal transmission linked to breeding activity. Transmission from possums to domestic animals appears to occur mainly during atypical behavioural interactions between the species, and this may well be important for badgers as well. Difficulties in controlling the disease adequately in domestic animals generally result from administrative problems since the necessary technical procedures are available and have been shown to be effective. Where there is interplay between infection in wildlife and domestic animals, eradication of the disease becomes impractical.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed2004

Evidence-based practice: examining the risk of toys in the microenvironment of infants in the neonatal intensive care unit.

Toys placed in the bed or microenvironment of infants in the neonatal intensive care unit (NICU) demonstrate high rates of colonization (92%). As with other fomites, toys may be one potential source of nosocomial infection (NI). This project critically evaluated the practice of placing toys in the microenvironment of critically ill infants by using the Iowa Model of Evidence-Based Practice to Promote Quality Care. With the model as a guide for decision making, the existing evidence was explored using a systematic review of the literature, case studies, scientific principles, theory, and expert opinion. A comprehensive review of the literature did not clearly identify a causal relationship between toys in the NICU microenvironment and NI. Levels of evidence suggesting an association between toys and NI were determined to be moderately strong and consistent. A plausible relationship between the practice of placing toys in the beds of NICU patients and risk for infection was found. These findings prompted a pilot practice change, eliminating toys in the NICU, to test the potential impact of this intervention. Pre- and postintervention infection rates were compared. NI rates decreased from 4.6 to 1.99 per 1,000 patient days over a 6-month evaluation period. Although this decrease was not statistically significant, it was the lowest rate recorded in 5 years. Ongoing evaluation of NI rates is in progress. Individual NICUs must determine if the evidence warrants a practice change in their setting.

Cross Infection↗
PubMed2006

Epidemiology of gastroenteritis on cruise ships, 2001-2004.

BACKGROUND: The incidence of diarrheal disease among cruise ship passengers declined from 29.2 cases per 100,000 passenger days in 1990 to 16.3 per 100,000 passenger days in 2000. In 2002, the Vessel Sanitation Program of the Centers for Disease Control and Prevention reported 29 outbreaks (3% or more passengers ill) of acute gastroenteritis on cruise ships, an increase from 3 the previous year. This analysis of gastroenteritis on cruise ships, conducted in 2005, details the increase in outbreak incidence rates during 2001 through 2004. METHODS: Using Gastrointestinal Illness Surveillance System data, investigators evaluated incidence rates of gastroenteritis on cruise ships calling on U.S. ports, carrying 13 or more passengers, by cruise length and reporting region during the study period. The investigators also evaluated the association between inspection scores, and gastroenteritis incidence and the frequency of outbreaks in 2001 through 2004. RESULTS: During the study period, the background and outbreak-associated incidence rates of passengers with acute gastroenteritis per cruise were 25.6 and 85, respectively. Acute gastroenteritis outbreaks per 1000 cruises increased overall from 0.65 in 2001 to 5.46 in 2004; outbreaks increased from 2 in 2001 to a median of 15 per year in 2002-2004. Median ship inspection scores remained relatively constant during the study period (median 95 on a 100-point scale), and were not significantly associated with either gastroenteritis incidence rates (risk ratio, 1.00; 95% confidence interval, 0.98-1.02) or outbreak frequency (Spearman's coefficient, 0.01, p=0.84). CONCLUSIONS: Despite good performance on environment health sanitation inspections by cruise ships, the expectation of passenger cases of gastroenteritis on an average 7-day cruise increased from two cases during 1990-2000 to three cases during the study period. This increase, likely attributable to noroviruses, highlights the inability of environmental programs to fully predict and prevent risk factors common to person-to-person and fomite spread of disease.

Acute Disease↗
PubMed2006

Phenotypes of isolates of Pseudomonas aeruginosa in a diabetes care center.

BACKGROUND: Pseudomonas aeruginosa is an invasive organism that frequently causes severe tissue damage in diabetic foot ulcers. A major problem in P. aeruginosa infection may be that this pathogen exhibits a high degree of resistance to a broad spectrum of antibiotics. Some researchers feel that P. aeruginosa is a homogeneous species, whereas others have suggested that they are panmictic. Here we characterized P. aeruginosa populations isolated from diabetic foot ulcer and from hospital environment specimens, both from a tertiary diabetes care center in Chennai, India. METHODS: Phenotypic methods like antibiotic susceptibility determinations using Kirby-Bauer's disc diffusion test and minimum inhibitory concentration (MIC) as well as outer membrane protein SDS-PAGE analysis of P. aeruginosa were performed. RESULTS: Twenty three isolates (29.8%) of P. aeruginosa from 77 diabetic foot ulcers and two environmental isolates (13.3%) from 15 different hospital fomites were detected. Both environmental isolates were sensitive to antibiotics than those isolated from clinical specimens by Kirby-Bauer's disk-diffusion method, which correlated the resistance levels by MIC determination. Outer membrane proteins (OMP) corresponding to 21, 23, 43, 46, 50, and 70 kDa were detected. CONCLUSIONS: The study is captivative as the resistance in P. aeruginosa from diabetic foot ulcers seems very common and because all the isolates were resistant to at least one or more antibiotics tested. Disk-diffusion and MIC results shows that piperacillin, amikacin and imipenem retain high levels of antipseudomonal activities and amikacin two times more active than the aforementioned antibiotics to enable itself as a potent antipseudomonal agent in diabetic foot infections. The OMP profile has revealed that clinical isolates were different from hospital environment isolates, which suggests that the origin of infections by P. aeruginosa is mainly due to growth of bacterial strains acquired by patients prior to hospital admission.

Bacterial Outer Membrane Proteins↗
PubMed2004

Two consecutive outbreaks of Acinetobacter baumanii 1-a in a burn Intensive Care Unit for adults.

UNLABELLED: Acinetobacter baumanii is generally a highly antibiotic resistant micro-organism that can be easily transmitted between inpatients of ICUs. We report two consecutive outbreaks of A. baumanii in a burn ICU. MATERIAL AND METHODS: All patients with ICU-stay greater than 2 days were subject to a strict epidemiological surveillance after admission, recording age, sex, TSBA, etc. and follow-up data such as antibiotherapy, instrumentation, infections, etc. We also monitored the microbial flora evolution and their resistance to antibiotic by weekly cultures of pharynx, rectum, skin (healthy and burned), etc. Because of an "epidemic" microorganism, infection control procedures, were increased. We studied the colonization by other prevalent microorganisms: MR-S. aureus and Pseudomonas aeruginosa. RESULTS: Seventy-two burn patients were followed in 1 year. Only 4.1% were infected at some site by A. baumanii, but 1/3 of patients were colonized by this microorganism, distributed in two outbreaks, one in the first trimester, after admission in the Unit of two non-burned and colonized patients (from another ICU). The second epidemic began in July and probably was due to transitory colonization of skin or fomites by health personnel working in both ICUs. All the isolates (from both ICUs) of A. baumanii were identical by PFGE. The length of hospital stay was the main risk factor for colonization. P. aeruginosa and MR-S. aureus showed a tendency to be endemo-epidemic at all times. CONCLUSION: Our cross colonization control measures showed a limited efficacy our burn patients. Therefore, we must impede the introduction to burn ICUs of epidemic microorganisms by colonized patients or heath personnel by restriction of admission of A. baumanii colonized patients from other ICUs (if the treatment can be administered in this ICU) and by strict disinfection/antiseptic procedures.

Acinetobacter Infections↗
PubMed2004

Survival of human enteric viruses in the environment and food.

Human enteric pathogenic viruses can enter the environment through discharge of waste materials from infected persons, and be transmitted back to susceptible persons to continue the cycle of disease. Contamination of food with viruses may also promote disease outbreaks. A number of studies have investigated the survival characteristics of several enteric viruses in various environments and foodstuffs, to help explain the transmissibility of these pathogens. This review deals with published work on enteric virus survival on fomites, and in waters, soil, and foods; the results of these studies have illustrated the robust survival of viruses in these environments. Much information is lacking, however, especially for foodstuffs and soils, and no detailed information is available concerning the survival of noroviruses, the most significant foodborne type.

Dairy Products↗
PubMed2005

Portrait of the national veterinary service as a surveillance continuum.

National veterinary services emerged in response to the animal disease challenges of centuries past. Their often singular preoccupation with exogenous disease preclusion yielded, by the early 1900s, to parallel commitments to control a number of serious indigenous, zoonotic infections. Advances in clinical pathology and epidemiology opened the door in many countries to disease, if not agent, eradication initiatives by the latter part of that century. The attending interval witnessed the explosive growth of international trade and the emerging or re-emerging conditions that threaten to accompany it. Animal disease agents, their hosts and the environments within which they interact vary considerably from nation to nation. Depicted as a medieval metaphor, the exogenous cluster around the walls of the castle, awaiting entry upon the next uninspected, unsuspecting fomite or beast. Some of these threats reside comfortably within the structure's bedding and detritus, sapping the vitality of its residents until detected and exterminated. Others emerge from the least expected crevices, growing insidiously or explosively in tandem with changes wrought by humans or nature. In anticipation of, or in response to, these myriad challenges, national veterinary services mount surveillance campaigns. From the national survey that denies the presence of exogenous disease to the post-eradication assessment that confirms its demise, surveillance forms the sensory acumen of the service. From the passive assessments that detect the emerging to the active regimens that plot progress against the indigenous, they form a continuum that defines the very nature of the national veterinary service.

Animal Diseases↗
PubMed2006

Hydrographics and the timing of infectious salmon anemia outbreaks among Atlantic salmon (Salmo salar L.) farms in the Quoddy region of Maine, USA and New Brunswick, Canada.

Infectious salmon anemia (ISA) has caused severe morbidity and mortality in farmed Atlantic salmon in North America, Norway, Scotland and the Faroe Islands. The Quoddy region of Maine, United States of America (USA), and New Brunswick (NB), Canada is characterized by extensive tidal mixing and close proximity between farms. This region is also prone to recurrent appearances of ISA, though control measures limit disease spread and severity on infected farms. We conducted a retrospective longitudinal analysis of the apparent impact of hydrographics on the incidence and timing of ISA outbreaks on Atlantic salmon (Salmo salar L.) farms in the Quoddy region from May 2002 to August 2004. A time-series cross-sectional regression of 32 farms over 28 months demonstrated a limited, but statistically significant, spatio-temporal clustering of ISA outbreaks linked hydrographically. New outbreaks correlated temporally with those occurring on-site 1 and 3 months prior, and those occurring within one tidal-excursion upstream the same month. Other risk factors included holdover of previous year-class fish, wharf sharing, and possibly harvests of cages infected in previous months. Conclusions suggest that tidal dispersion does play a role in ISAV transmission in the Quoddy region. Dispersal of free virus and/or tidal distribution of lice or other hydrographically influenced vectors or fomites could all contribute to the spatio-temporal patterns described.

Animals↗
PubMed1975

Outbreaks of Serratia marcescens infections in a cardiothoracic surgical intensive care unit.

An outbreak of infections with pigmented Serratia marcescens involving 3 patients in a cardiothoracic surgical intensive care unit is reported. A respirator is thought to have been the source of pneumonia in 2 patients, and fomite spread from 1 of these is considered responsible for the induction of fatal endocarditis in the third patient. This outbreak demonstrates the rapid dissemination of a bacterial strain within the unit, several methods of dissemination, the wide variation in apparent virulence of the organism, the alterations of antibacterial host defense which made bacterial disease possible and which determined the site of infection, and the difficulties of adequate therapy. The third patient is the seventh reported with serratia infection of a prosthetic heart valve.

Adolescent↗