Nosocomial hepatitis a transmission by an adult patient with diarrhea

Nosocomial Hepatitis A Transmission by an Adult Patient with Diarrhea

RICHARD

A.

GOODMAN,

CAROL

C. CARDER,

JAMES

R. ALLEN,

WALTER

A.

ROBERT

J. FINTON,

M.D.

R.N. MD

ORENSTEIN,

M.D.

M.S.P.H.

Atlanta, Georgia

From the Field Services Division, Epidemiology Program Off ice, the Hospital Infections Program, Center for Infectious Diseases, and the Immunization Division, Center for Prevention Services, Centers for Disease Control: the Office of Epidemiology, Georgia Department of Human Resources; and the Office of Epidemiology, Fulton County Health Department, Atlanta, Georgia. Presented in part at the Twenty-First Interscience Conference on Antimicrobial Agents and Chemotherapy, November 4-6, 1961, Chicago, Illinois. Requests for reprints should be addressed to Cr. James R. Allen, Hospital Infections Program, Center for Infectious Diseases, Centers for Disease Control, Atlanta, Georgia 30333. Manuscript

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Hepatitis A occurred in five registered nurses, a licensed practical nurse, and a recently discharged patient at a community hospital; one of these seven was asymptomatic. All had been exposed to a woman with confirmed hepatitis A who had undergone elective cholecystectomy and who had had vomiting, diarrhea, and fecal incontinence during the eight days before onset of jaundice. Of the 107 hospital workers identified as having at least some exposure to the source patient, 58 (54.2 percent) had no pre-exlstlng antibody to hepatitis A virus (anti-HAV) and were considered susceptible. Six persons, including the five clinically ill registered nurses, had IgM-specific anti-HAV. The infection attack rate was 5.8 percent for all exposed hospital workers but 10.3 percent for the 58 who were serosusceptlble. Risk of infection was highest for persons with documented or probable contact with the source patient and for registered nurses. Among hospital personnel, the prevalence of anti-HAV increased with age but varied inversely with socioeconomic status. Hospital personnel and patients may be at risk for hepatitis A infection when exposed to patients who are in the prodromal stage of hepatitis A. Vomiting, diarrhea, and fecal incontinence may increase the risk of transmission. Hepatitis type A is not usually considered a significant hazard for hospital workers and other health care providers [ 11. Accordingly, recommendations for the prevention and control of nosocomial hepatitis have primarily concerned type B and non-A non-B hepatitis [WI. This report describes an outbreak of nosocomial hepatitis A among hospital personnel providing care for and the hospital roommate of a patient with vomiting and diarrhea in whom hepatitis A was diagnosed three weeks after elective cholecystectomy. The commercially available serologic test for differential detection of preexisting antibody to hepatitis A virus (anti-HAV) and acute (IgM-specific) anti-HAV permitted us to define risk factors for infection, to detect infected persons who were not ill, to accurately determine infection rates for groups exposed to the source patient, and to study the prevalence of pre-existing antibody to hepatitis A virus in general hospital personnel. The outbreak occurred in October 1980 in a 391-bed community hospital employing approximately 1,500 persons. The problem was detected when laboratory-confirmed hepatitis A was found in two registered nurses who worked on the same ward.

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METHODS Case Ascertainment and Epkkniokglc Studies. Persons at the hospital with secondary hepatitis A were identified by investigation of the following for the period September 1 through November 15, 1980: hospital workers who reported symptoms of viral hepatitis through the nursing office or the employee health unit; all persons admitted to or discharged from the hospital with a diagnosis of viral hepatitis; and all persons for whom hepatitis diagnostic tests had been submitted to the hospital clinical laboratory. Each clinical case of hepatitis A was diagnosed by a physician and confirmed serologically by the presence of IgM-specific anti-HAV. All hospital personnel who may have had direct contact with or indirect exposure to the source patient during her hospitalization were identified by reviewing the medical records of the source patient for the names of those with documented exposure (e.g., persons who administered medications or performed procedures); by determining personnel activities through review of employee work records and by interviews on the ward where the source patient was hospitalized: and by reviewing the records of other departments in the hospital for documentation or evidence of employee exposure to the source patient. Hospital workers were assigned to one of three categories of exposure: in those with documented physical contact with the source patient, exposure was called ‘definite”; in those whose activities would have resulted in exposure to the source patient, although exposure was not documented in the medical record, expo-

sure was called “probable” (e.g., nursing assistants); and in those for whom exposure could have occurred, but with less certainty, exposure was called “possible” (e.g., housekeeping personnel). Questbnnalre and SerologicStudies. A questionnaire was administered to all exposed hospital workers to obtain demographic data and information about job type, recent illness compatible with hepatitis, exposure to other known or possible cases of hepatitis, past history of hepatitis or liver disease, and routine handwashing practices in the hospital. All serum samples from patients and exposed workers were tested for the presence of anti-HAV or IgM-specific a@-HAV using radioimmunoassay procedures (HAVAB and HAVAB-M, Abbott Laboratories, N. Chicago, Illinois’). Serum samples from the source patient and those with secondary cases were also tested for the presence of hepatitis B surface antigen (HBsAg) and antibody to both HBsAg (anti-HBs) and hepatitis B core antigen (anti-HBc) using standard commercial procedures. A serum specimen was obtained between October 22 and November 2 from all workers identified as exposed to the source patient and tested to identify subclinically infected personnel and to define susceptible personnel who were at risk of hepatitis A infection. Persons lacking antiHAV and those who were IgM-positive were considered to have been serosusceptible during the period of exposure, September 1 through 16. Thirty-five workers with job assignments similar to those

Use of trade names is for identification only and does not imply endorsement by the Department of Health and Human Services or l

the Public Health Service.

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of the exposed group, but who were not exposed to the source patient, were selected in a non-random fashion to participate in the serologic and questionnaire surveys voluntarily. Socioeconomic rank of hospital workers was established for each job type by defining three groups based on starting salaries in 1980: $7,700 or less per year; $8,000 to $9,300 per year; and $10,800 or more per year. A minimal estimate of direct costs associated with the outbreak was obtained by cumulating costs of hospitalization for secondary cases and wages paid to the workers during their hospitalization and convalescence. Statistical analyses were performed using the Fisher exact test and linear logistic regression analysis (BMDP, 1979).

RESULTS Source Patient. The probable source patient was quickly identified through hospital records as a 32 year old woman who had been admitted to a 5Obbed surgical ward of the hospital on September 1 for elective cholecystectomy (Figure 1). She was asymptomatic when admitted; physical examination showed no jaundice or abdominal tenderness. Laboratory results included total bilirubin level of 0.6 mg/dl and serum glutamic oxaloacetic transaminase level of 22 mp/ml. CM September 2, she underwent elective cholecystectomy; no intraoperative problems occurred and a surgical drain was not used. The postoperative course was complicated by fever beginning on September 3, abdominal pain and distention, and, from September 6 through 10, intermittent diarrhea and vomiting. Review of the chart and interviews with ward personnel and her hospital roommate indicated that, because of her discomfort, she required analgesics, intravenous fluids, and assistance in walking to the bathroom. On several occasions, she had diarrhea1 incontinence with gross contamination of her bed linen or the floor. On September 14, clinical jaundice was noted and a total bilirubin level of 5.4 mg/dl and serum glutamic oxaloacetic transaminase value of 2,100 mp/ml were documented. She was discharged on September 16 without a specific diagnOSiS but was readmitted to a different ward from September 23 through 25 for further diagnostic evaluation of her jaundice. Test results for hepatitis B (HBsAg, anti-HBs, and anti-HBc) were negative; however, IgMspecific anti-HAV result was positive, confirming the clin_ical diagnosis of acute hepatitis A. Epidemiologic Investigation. From September 29 through October 17, six other persons had clinical onset of laboratory-confirmed hepatitis A, including five of the 107 hospital workers exposed to the source patient during her first admission (Figure 1). None of the 1,374 hospital workers without exposure to the source patient had clinically diagnosed hepatitis A (p
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LABORATORY

I

A-GOODMAN

VALUES

5

9

ET AL.

FOR SOURCE

I3

17

21

PATIENT

25

SEP

SOURCE PATIENT HOSPlTALlZEO I

9

5

13

I7

21

25

29

3

7

It

SEP t

f

f

I5

I9

23

27

31

OCT t

Figure 1. Correlation of hospital course of hepatitis A source patient with laboratory values and with onset of illness in secondary cases.

the source patient during her first hospital admission (Table I). Each of the five nurses had documented contact with the source patient. The hospital roommate assisted the source patient in the bathroom and removed a urine volume-measuring container from the toilet after it had been used by the source patient. The duration between first (or only) exposure to the source patient and onset of illness in the secondary cases ranged from 24 to 45 days, consistent with the incubation period for hepatitis A. The serologic survey among exposed personnel detected one additional employee with secondary infection, a licensed practical nurse who was asymptomatic (Table I). Because more

TABLE I

than 14 days had elapsed since exposure, immunoglobulin was not recommended for exposed personnel. Contact with the source patient was the only common link shared by those with secondary cases; none had been exposed to other known cases of hepatitis A. The only other employee known to have had hepatitis A in 1980 was unrelated both temporally and by epidemiologic investigation to the outbreak. Of the 107 hospital workers identified who may have been exposed to the source patient during her first hospitalization, 94 (88 percent) were female, and 58 (54 percent) were white, 45 (42 percent) black, and four (4

Confirmed Cases of Secondary Nosocomlal Hepatitis A Infection

Case

onset

Type of Exwsurds)

Ace (yr)

to Source Case

Registered nurse (floor)

Sept. 29

56

Hospital roommate Registered nurse (floor)

Oct. 2 Oct. 6

35 23

Registered nurse (intravenous team) Registered nurse (recovery room) Registered nurse (intravenous team) Licensed practical nurse (floor)

Oct. 10

26

Assisted in bed and to bathroom; cleaned up emesis; administered intramuscular medications Handled Specipan with urine, ? feces Assisted in bed; inserted nasogastric tube; was contaminated with vomitus; changed intravenous apparatus; gave enemas Started intravenous infusion

Oct. 14

33

Changed oral airway; ? handled nasogastric tube

Oct. 17

33

Started intravenous infusion

Asymptomatic

29

Assisted to bathroom: irrigated nasogastric tube; gave intramuscular medications; changed intravenous apparatus

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TABLE II

ET AL.

Exposed Personnel: Index of Exposure and SuscefHlbHfty to Hepatltls A Virus by Job Type Type d

JobTyps Registered nurse Nursing assistant Licensed practical nurse Housekeeping worker Respiratory technician Laboratory technician Physician Laundry worker Radiology technician Ward clerk Total

DOCUlllOlll~

susceptlMe

Exporwe

PrObW

Number

Total

(Pmw

24 0 10

4 14 0

6 11 3

34 25 13

25 14 4

(73) (56) (31)

0 9 0 4 0 1 0 48

1 0 5 0 0 0 0 24

9 0 2 0 3 0 1 35

10 9 7 4 3 1 1 107

2 4 3 4 1 0 1 58

(20) (44) (43) (190) (33) (0) (100) (54)

percent) Hispanic. Nursing service employees represented more than two-thirds of those exposed (Table II). Of the 48 persons who had documented contact with the source patient, the majority were registered nurses, licensed practical nurses, and respiratory therapy technicians (Table II). For all exposed workers, the attack rates for clinically apparent hepatitis A was 4.7 percent and for hepatitis A infection was 5.6 percent (Table Ill). The infection rate for the 58 exposed susceptible workers was 10.3 percent, but for those serosusceptible workers in the categories most likely to have been exposed (the “definite” and “probable” categories), the infection rate was 14.6 percent. Serosusceptibility by job type among exposed workers varied widely (Table II). Other than physicians, registered nurses had the greatest proportion (73 percent) of susceptible persons. The susceptible nurses also experienced the highest attack rate: five (20 percent) of the 25 susceptible registered nurses and one (25 percent) of the four susceptible licensed practical nurses had secondary cases. Of the 142 workers surveyed, 62 (43.7 percent) had pm-existing anti-HAV; only three of those with anti-HAV gave a past history of hepatitis, an estimated ratio of illness to infection of 4.8 percent. The prevalence of anti-HAV, standardized for age and social class, increased from 0 percent in persons younger than 20 years of age to 63 percent in those older than 50 years (p = 0.001) but varied inversely with socioeconomic status as measured by starting annual salary, from 22 percent in those earning $10,800 or more to 56 percent in those earning $7,700 or less (p = 0.006). Physicians and registered nurses, representing the job categories with the highest starting salaries, had the lowest prevalence of anti-HAV. The frequency of handwashing by hospital personnel after direct patient contact varied considerably by job category. Ninety percent of respiratory therapy tech-

nicians stated they washed their hands after every direct patient contact; only 75 percent of licensed practical nurses, 69 percent of nursing assistants, and 43 percent of registered nurses made this assertion. The direct cost for the outbreak was estimated to be $60,000 for hospitalization and wages paid to ill employees during their illness and convalescence. COMMENTS Viral hepatitis has long been recognized as an occupational hazard for health care providers [4-71. The risk of acquiring hepatitis B is firmly established for certain hospital personnel, including hemodialysis and oncology unit staff members, laboratory technicians, and others exposed to blood products [8,9]. More recently, nosocomial transmission of non-A non-B hepatitis agent has been documented [ lo]. Nosocomial hepatitis A, however, is believed to be uncommon for several reasons. First, maximal excretion of hepatitis A virus in feces occurs during the prodromal stage of infection and precedes the onset of jaundice [ 111. Since most patients hospitalized for hepatitis A are admitted only after they become jaundiced, they are probably not excreting high titers of virus at the time of admission and are less infectious [ 12,131. Second, patients admitted to the hospital with a diagnosis of hepatitis A may be considered by the staff as

TABLE Ill

Attack Rater for Exposed Personnel’ by Serologic Status and Index of Exposure

Typs sf At&k Rate Overall clinical Overall infection Overall serosusceptible Documented/probable serosusceptible l

Numbwol

Nw&wol

C@XJs

EVrJssd

5 6 6 6

107 107 58 41

Attack Rate 4.7% 5.6% 10.3% 14.6%

107 hospital workers were exposed to the source patient.

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infectious: the use of enteric precautions and other modified patient care and environmental control activities probably reduces the risk of transmission. Finally, the serologic test that allows etiologic confirmation of hepatitis A infection has only recently been available commercially. Before the availability of this test, sporadic cases or outbreaks of nosocomial hepatitis A may not have been recognized, and even those that were could not have been confirmed [ 14-161 or may not have been reported for a variety of reasons. This outbreak documents that under certain circumstances nosocomial transmission of hepatitis A virus does occur. Since the source patient was asymptomatic at the time of admission for an elective surgical procedure and did not provide a history of exposure to hepatitis A, hospital personnel initially had no reason to be unusually concerned about hepatitis A infection. Moreover, since the postoperative period coincided with and was complicated by the prodromal stages of hepatitis A infection, the diagnosis of hepatitis as a distinct problem was further obfuscated. Finally, the diarrhea and fecal incontinence experienced by the patient probably enhanced the efficiency of transmission of hepatitis A virus. The fecal-oral route is the primary mode of transmission for hepatitis A infection [ 171. Transmission of hepatitis A virus by other means (e.g., through infectious serum, sputum, saliva, and urine) is not thought to be of major epidemiologic significance. The route of transmission in this outbreak probably was fecal-oral, although other less common routes cannot be excluded. Since there is evidence that hepatitis A virus is excreted in bile [ 181, transmission in this outbreak could also have occurred as a result of exposure of those who acquired secondary cases to vomitus or bile-contaminated nasogastric suction materiaf, as in the case of the recovery room nurse (Table I). Nosocomial outbreaks of hepatitis A have probably involved both food-borne and person-to-person transmission [ 19,201. Three outbreaks of nosocomial hepatitis A have been linked to pediatric patients with diarrhea or fecal incontinence during the prodromal stage of infection [21-331. As in the present report, three features characterized each of these outbreaks: the source patients were anicteric when admitted to the hospital, and exposure to hepatitis A was neither suspected nor elicited by history; the purposes for hospitalization-Shigella dysentery [21], amebiasis [22], and cardiac catheterization [ 231 -were unrelated to viral hepatitis; and fecal contamination of the environment occurred during hospitalization. This outbreak differs from the others, however, in that the source patient was an adult. Data describing the prevalence of anti-HAV in health

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care personnel are limited. Recently, however, Maynard [l] reported that the prevalence of anti-HAV was equal in groups of physicians representing different specialities. Szmuness et al. [24] studied hemodialysis center personnel and patients and found that the incidence of hepatitis A infection in the staff during the one-year study period was not increased, and that the prevalence of anti-HAV varied by job type [ 241. Data have not been published previously about the seroprevalence of anti-HAV in general hospital personnel: the serologic data in this study, however, are consistent with patterns reported for the general population [25,26]. The seroprevalence of anti-HAV increases with age and varies inversely with socioeconomic rank as defined by starting salary. The implications for preventing outbreaks of nosocomial hepatitis A such as the one described in this report are significant; in addition to morbidity associated with the secondary cases, the estimated cost of this outbreak exceeded $60,000. This figure predominantly reflects hospitalization costs but also includes wages paid for 196 person-days of lost work time. Recommendations have been published for prevention of nosocomial transmission of all types of viral hepatitis by patients who are jaundiced when admitted to the hospital [2,3]. This outbreak suggests that measures should be considered for preventing transmission of infection from anicteric patients not suspected as having acute hepatitis A. Prevention programs might include education for new employees and periodic in-service programs for all employees about the types of hepatitis, modes of transmission, and methods of prevention, including the importance of handwashing [27] and related hygienic practices. A comprehensive hospital infection control program that includes surveillance and control activities and employee health services is important to provide a coordinated approach to this type of problem. Immunoglobulin prophylaxis should be considered for hospital personnel exposed directly to a patient with diarrhea hospitalized during the prodromal stage of hepatitis A; immunoglobulin is most effective if given within two weeks of exposure [ 281. The few studies that assess or quantify handwashing practices of hospital personnel suggest that such practices are frequently suboptimal [29-311; our findings support this conclusion. Other aspects of personal hygiene practiced by patient care personnel are also important in preventing transmission of infection to themselves or others. In preventing oral transmission of infection, it is of major importance that workers avoid touching fingers to or putting objects (e.g., intravenous tubing or syringes) in the mouth. The importance of meticulous patient care techniques is

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to hospital personnel is real, although poorly defined and overshadowed by interest in the prevention and control of other types of viral hepatitis. This outbreak again illustrates that specific conditions may be necessary for person-to-person transmission of hepatitis A in a hospital. These include hospitalization of a source patient during the prodromal stage of infection, fecal contamination of the hospital environment especially by diarrhea, suboptimal patient care techniques or poor hygienic practices by patient or hospital workers, and a population of susceptible persons exposed to the source patient or infectious feces.

emphasized by the fact that three of the five infected nurses in this outbreak were intravenous therapy team or recovery room nurses whose exposures to the source patient were limited both in time and type of contact. Feces of all patients must be regarded as highly contaminated with bacterial and possibly viral and other pathogens. Precautions that might be taken routinely, therefore, when hospital workers must have direct contact with feces or objects such as bedpans that are heavily fecally contaminated include the wearing of disposable gloves and careful washing of hands immediately after completion of the task. Our investigation and circumstances relating to the other confirmed outbreaks of nosocomial hepatitis A also suggest the need to consider managing patients who have diarrhea and who are fecally incontinent with enteric precautions [27]; such precautions may include isolation of the patient in a private room and use of gown and gloves for all workers when providing close or prolonged direct care for the patient. The risk of nosocomial transmission of hepatitis A

1.

HEPATITIS

ACKNOWLEDGMENT We are grateful to Harold D. Meltzer, M.D., Stephen C. Hadler, M.D., J. David Smith, Mary C. White, MS., and Michael B. Gregg, M.D. for their contributions during the investigation. Persons who assisted in the preparation and review of the manuscript include Mrs. Elaine Brock, Michael T. Osterholm, Ph.D., Michael J. Shea, M.D., Peter M. Layde. M.D., R. Keith Sikes, D.V.M., and Allen W. Hightower, M.S.

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hospitals, 2nd ed. Washington, D.C.: U.S. Government Printing Office, 1975. Centers for Disease Control: Recommendation of the Public Health Service Immunization Practices Advisory Committee: immune globulins for protection against viral hepatitis. Morbid Mortal Weekly Rep 1981; 30: 423-428, 433435. Fox MK, Langner SB, Wells RW: How good are handwashing practices? Am J Nurs 1974; 74: 1676-1678. Albert RK, Condie F: Hand-washing patterns in medical intensive-care units. N Engl J Med 1981; 304: 1465-1466. Preston GA, Larson EL, Stamm WE: The effect of private isolation rooms on patient care practices, colonization and infection in an intensive care unit. Am J Med 1981; 70: 641-645.