William M. Valenti

Nosocomial viral infections: I. Epidemiology and significance.

Viral illnesses in Strong Memorial Hospital were monitored over a 17-month period. Using criteria based primarily on the incubation periods for a number of common virus infections, the infections we found were classified as hospital- or community-acquired. Hospital-acquired viral infections occurred on most hospital services; the majority of infections occurred on the pediatric and psychiatric services. Infections due to herpesviruses were seen more frequently in a group of patients aged 14 years or older, while infections in patients aged three years or younger were more likely to be due to respiratory syncytial virus, influenzavirus, adenovirus, or parainfluenza virus. Patients with nosocomial infections due to viruses were hospitalized an average of 9.3 days longer than uninfected controls; thus nosocomial viral infections result in increased costs of hospitalization.

Concurrent outbreaks of rhinovirus and respiratory syncytial virus in an intensive care nursery: epidemiology and associated risk factors.

An outbreak of viral respiratory disease occurred in eight infants in a neonatal intensive care unit during the 1980 winter respiratory season. Four infections with respiratory syncytial virus and four infections with rhinovirus were identified. Epidemiologic investigation revealed that viral respiratory infection was significantly associated with intubation with orotracheal tubes (P = 0.001), with the presence of both a nasal feeding tube plus an orotracheal tube together (P = 0.007), and with assisted ventilation (P = 0.009) when compared to uninfected controls. Twenty-seven of 85 (30.6%) personnel working in the unit at the time of the outbreak reported a history of upper respiratory illness during the week prior to the outbreak, and 46 (54.1%) of them had had contact with patients in areas of the hospital where patients infected with RSV and rhinovirus were housed. The data suggest that both viruses were transmitted to the babies by hospital personnel. Rhinoviruses can be nosocomial pathogen in neonates with compromised pulmonary function, and the clinical presentation of rhinovirus infection in neonates may be difficult to distinguish from that produced by RSV.

Nosocomial viral infections: II. Guidelines for prevention and control of respiratory viruses, herpesviruses, and hepatitis viruses.

This article reviews the most likely mechanisms of transmission of the commonly encountered respiratory viruses (influenza, respiratory syncytial virus, parainfluenza, rhinovirus), herpesviruses, and hepatitis viruses, and presents the guidelines used currently for prevention and control that are in use at Strong Memorial Hospital.

Survey of hospital personnel on the understanding of the acquired immunodeficiency syndrome

The recent emergence of the acquired immunodeficiency syndrome (AIDS) has generated a significant amount of media coverage. Often referring to the “gay plague” and “new killer disease,” many publications have taken an alarmist rather than an informative tone, thereby creating much concern and confusion among the general population and health care workers alike. Hospital personnel are not immune to this type of sensationalism. Misconceptions about the transmissibility of AIDS and concern over what types of infection control precautions are necessary have been reported in hospitals across the country. There have also been incidents in which employees have quit their jobs rather than work with a person with AIDS, this in spite of information from the Centers for Disease Control that there have been no documented cases of AIDS in health care personnel not already in high-risk groups.’ Very early, working groups from various organizations including the University of California,2 the American Medical Association3 and the American Hospital Association4 agreed that there is no scientific reason for health care workers to be excused from caring for persons with AIDS. Evidence to date tells us that the risk of trans-

Infection control and the pregnant health care worker.

Health care workers may be exposed to a variety of infectious agents in the workplace. The pregnant health care worker presents additional concerns because of the potential risk of infection to the developing fetus. Health care workers often misunderstand the basic elements of infection transmission. The result of this misinformation is that personnel are most often concerned about the agents that are least transmissible. To develop an infection control program that is rational and workable, the infection control practitioner must have a thorough understanding of the mechanisms of disease transmission. With this foundation, an infection control program for the pregnant health care worker will rarely involve transfer to alternative assignments or work restriction based on pregnancy alone. The approach outlined in this article stresses a more generic approach to infection control by isolating the disease and not the employee.

Nosocomial Viral Infections: III. Guidelines for Prevention and Control of Exanthematous Viruses, Gastroenteritis Viruses, Picornaviruses, and Uncommonly Seen Viruses

This communication is the third in a four-part series on nosocomial viral infections from the Strong Memorial Hospital. This third article discusses guidelines for prevention and control of exanthematous viruses, gastroenteritis, viruses, adenoviruses and the picornaviruses other than rhinoviruses. Several uncommonly seen viruses, such as the virus of Creutzfeldt-Jakob disease and Marburg, Ebola, and Lassa fever viruses, also are reviewed briefly.

Nosocomial Viral Infections: IV.Guidelines for Cohort Isolation, the Communicable Disease Survey, Collection and Transport of Specimens for Virus Isolation, and Considerations for the Future

Virus transmission within the hospital is related to transmissibility of the virus and susceptibility of the population at risk. General guidelines for the use of cohort isolation, for the control of virus transmission in the hospital, and for the use of the communicable disease survey for pediatric patients and visitors to the hospital are out-lined. We also present a brief review of how to collect and transport specimens for virus isolation to assist the infection control practitioner and the clinician and conclude with recommendations for further investigations in the areas of virology and infection control.

Infection control and clinical thermometry: Perforation of soft plastic thermometer sheaths during temperature measurement

Plastic thermometer sheaths have gained widespread use in recent years. These thin, flexible sheaths are designed to cover conventional mercury-in-glass thermometers and have been advertised as presenting a clean thermometer to the patient with each use. The purpose of this investigation was to evaluate these thermometer sheaths in both a clinical and laboratory setting. Our results show that plastic thermometer sheaths tend to develop multiple perforations during use and do not provide a barrier between the mucous membranes of the mouth and the thermometer. We conclude that plastic sheaths are of limited use in oral temperature measurement, that they are not a substitute for the usual methods of disinfection of thermometers, and that they are probably unnecessary from an infection control standpoint.

AIDS Update: HTLV-III Testing, Immune Globulins and Employees with AIDS

As we have become experienced in dealing with AIDS, we have learned that early concern over employees who refuse to care for patients with AIDS was merely the tip of the iceberg from the infection control standpoint. During the past 5 years, additional questions and concerns have been raised regarding employee health and AIDS. An interesting body of literature has emerged recently that discusses many of these current employee health issues. Some of these questions have been answered in major communications in The New England Journal of Medicine , the Journal of the American Medical Association , and The Lancet . Many other topics have been covered in short communications in letters to the editor in these same journals and in the CDCs Morbidity and Mortality Weekly Report (MMWR) . When taken together, this writing presents a very clear picture of what is happening with AIDS in the health care arena. It is obvious that most of the concerns regarding AIDS in health care settings can be answered by taking a close look at the available epidemiologic data. It is important to remember that the decision-making process related to AIDS is easier if we try to separate the emotional issues surrounding the disease from the scientific data available.

Employee Health and the Infection Control Practitioner—Why Bother?

The hospital is a unique workplace in terms of the infectious hazards it presents to its employees. Traditionally, infection control programs have focused on various aspects of infection control in patients. However, infections constitute a risk for health care workers, a fact which emphasizes the importance of infection control input into the employee health program. Many health care facilities and most regulatory agencies recognize the importance of infection control in health care workers. However, infection control programs have had varying degrees of influence in occupational health matters. As the discipline of infection control has grown and become more sophisticated, the subdiscipline of employee health has also begun to grow and emerge with a data base of its own. Many infection control conferences, symposia, and meetings now have a session or two related to employee health. Perhaps even more important is the CDC Guideline for Infection Control in Hospital Personnel, written by a CDC panel as part of its guidelines series. It will be responsible for drawing attention to employee health issues as they relate to infection control and should help solidify the discipline. The guideline will also provide opinions and answers to many questions regarding infection control and employee health.