Patricia W. Stone,* Sean P. Clarke,† Jeannie Cimiotti,* and Rosaly
Correa-de-Araujo‡
*Columbia University School of Nursing, New York, New York, USA;
†University of Pennsylvania School of Nursing, Philadelphia,
Pennsylvania, USA; and ‡Agency for Healthcare Research and Quality,
Rockville, Maryland, USA
http://www.cdc.gov/ncidod/EID/vol10no11/04-0253-G.htm
Staffing patterns and nurses' working conditions are risk factors for
healthcare-associated infections as well as occupational injuries and
infections. Staffing shortages, especially of nurses, have been
identified as one of the major factors expected to constrain hospitals'
ability to deal with future outbreaks of emerging infections. These
problems are compounded by a global nursing shortage. Understanding and
improving nurses' working conditions can potentially decrease the
incidence of many infectious diseases. Relevant research is reviewed,
and policy options are discussed.
The Institute of Medicine's report, To Err is Human, which
spotlighted the problem of patient safety, reported that tens of
thousands of Americans die each year as a result of human error in the
delivery of health care (1). Authors of a more recent Institute of
Medicine report, Keeping Patients Safe, Transforming the Work
Environment of Nurses, concluded that nursing is inseparably linked to
patient safety and emphasized that poor working conditions for nurses
and inadequate nurse staffing levels increase the risk for errors (2).
Nurse working conditions are related to patients' risk of
healthcare-associated infections and occupational injuries and
infections among staff (3). We discuss the nurse workforce, review
research examining nursing as it relates to infectious disease, identify
gaps in the literature, and discuss potential policy options. Although
our focus is on the nursing workforce in the United States,
international trends and comparisons are also discussed.
The Nursing Workforce
Nearly 3 million registered nurses (RNs) work in the United States.
Ninety-five percent of these nurses are women, as are most of the
700,000 licensed practical nurses and >2 million unlicensed nurse
assistants. Internationally, occupational distributions are similar.
More than 1 million RNs work in hospitals, which makes nursing the
largest hospital workforce. In 60% of U.S. hospitals, vacancy rates for
RNs have increased since 1999; 14% of hospitals now report a severe
nurse shortage (i.e., >20% of positions vacant). The American Hospital
Association has reported that hospitals have up to 168,000 vacant
positions; 126,000 (75%) of the available positions in these hospitals
are for RNs (4). The current nursing shortage is related to an aging
workforce, problems with retaining licensed personnel, and difficulty
recruiting young people into the nursing workforce. The demand for RNs
is projected to grow by 22% by 2008, and unless market corrections are
made, the nursing shortage may reach 800,000 vacant positions by 2020
(5). Recent reports document that the nursing shortage is a severe and
growing global problem (4).
Historically, the turnover rate among nurses is more than double that
for other professionals of comparable education and sex (6). Recent
estimates in U.S. hospitals of RN turnover and intention to quit have
ranged from 17% to 36% (6,7), figures that compare to an overall
turnover rate of 2.2% for those employed in health services and social
services and 1.2% for those employed in educational services. In an
investigation of the effects of various nurse working conditions in
intensive care units, researchers found >17% of RNs indicated their
intentions to quit within 1 year (P.W. Stone, unpub. data). This finding
was disconcerting because this national U.S. sample of 2,324 RNs was
highly qualified; their average experience in health care was 15.6 years
(SD = 9.20), and their average tenure in their current position was 8.0
years (SD = 7.50). Of those intending to leave, 72% expressed poor
working conditions as the reason. In an American Hospital
Association–sponsored study, researchers estimated the cost of replacing
one RN to be $30,000–$64,000 (4).
To cover patient census fluctuations and unplanned absences and to
fill vacant positions caused by this nursing shortage, many healthcare
facilities have increased nurses' patient loads or expanded the use of
nonpermanent staff, such as float pool and agency nurses (4). Concerns
have been voiced that reliance on agency nursing services elevates
hospital costs, increases the fragmentation of health care, and
discourages longer term proactive solutions to staffing shortages that
would improve the morale of the permanent staff as well as the quality
of patient care services (8). Extended work shifts and overtime for
nurses have also escalated; however, nurses report making more errors
when working shifts >12 hours, working overtime, or working >40 hours
per week (9).
To increase the overall supply of nurses, many countries are
increasingly relying on international recruitment and migration (10).
The percentage of foreign-trained nurses in the United States is 4%,
compared to 8% in the United Kingdom and 23% in New Zealand (11).
However, the actual number of foreign-trained nurses in the United
States is 90,000, which compares to 42,000 in the United Kingdom (12).
In 2002, for the first time more foreign-trained nurses (n = 16,155)
were newly registered in Britain than were those who had been educated
within the country (n = 14,538). Many concerns exist about clinical
competencies, cultural sensitivity, and ethics of the practice of
importing nurses (13). While international recruitment can be a solution
in one country, it can create additional shortages in others.
Nursing and Healthcare-associated Infections
A recent evidence-based practice report sponsored by the Agency for
Healthcare Quality and Research concluded that a relationship exists
between lower levels of nurse staffing and higher incidence of adverse
patient outcomes (14). Nurses' working conditions have been associated
with medication errors and falls, increased deaths, and spread of
infection (15–30) (Table). RN staffing levels have been associated with
the spread of disease during outbreaks (17,22,23,25,28). However,
increasing nurse-to-patient ratios alone is not adequate; more complex
staffing issues appear to be at work. Many studies have found that the
times of higher ratios of "pool staff" (i.e., nursing staff who were
members of the hospital pool service or agency nurses) to "regular
staff" (i.e., nurses permanently assigned to the unit) were
independently associated with healthcare-associated infections
(16,17,21,27). The skill mix of the staff, that is, the ratio of RNs to
total nursing personnel (RNs plus nurses' aides), is also related to
healthcare-associated infections; increased RN skill mix decreases the
incidence of healthcare-associated infections (20,29,30). In a recent
comprehensive review of the literature, the authors concluded that
evidence of the relationship between nurses' working environment and
patient safety outcomes, including healthcare-associated infections is
growing. They also concluded that stability, skill mix, and experience
of the nurse workforce in specific settings are emerging as important
factors in that relationship (31).
Nurses' Work and Occupational Exposure to Infectious Disease
All healthcare workers face a wide range of hazards on the job,
including blood and body fluid exposure as well as musculoskeletal
injuries related to ergonomic hazards from lifting and repetitive tasks;
nursing personnel often experience these hazards most frequently (32).
In 2001, U.S. hospitals reported 293,600 nonfatal occupational injuries
and illnesses among their personnel. Among the eight private U.S.
industries with >100,000 injuries and illnesses annually, the number of
cases of nonfatal injury or illness in hospitals is the second highest;
and the incidence rate of injuries and illnesses per 100 fulltime
workers employed in nursing and personal care facilities is 13.5; by
contrast, the national average is 1.8. In 2001, nursing aides and
orderlies reported the highest number of occupational injuries that
resulted in days away from work of any service industry (70,300); RNs
had the second highest number (24,400) (33).

Nurses' Working Conditions: Implications for Infectious Disease
Patricia W. Stone,* Sean P. Clarke,† Jeannie Cimiotti,* and Rosaly
Correa-de-Araujo‡
*Columbia University School of Nursing, New York, New York, USA;
†University of Pennsylvania School of Nursing, Philadelphia,
Pennsylvania, USA; and ‡Agency for Healthcare Research and Quality,
Rockville, Maryland, USA
Figure. Blood and body fluids' exposure by personnel category.
Source: National Institute for Occupational Safety and Health (34).
Work-acquired infectious diseases are among the risks all healthcare
workers face; and bloodborne pathogens figure prominently among these.
Occupational exposure to blood and body fluids is well documented among
healthcare workers. Annual exposure prevalence rates range from <10% to
44%, depending on the occupational subgroup (34). Every year,
approximately 600,000–800,000 occupational needlestick injuries occur in
the United States (34). In a study of 60 U.S. hospitals in a 4-year
period, nurses were the most likely to experience a blood or body fluid
exposure (Figure) (34). Most exposures involve percutaneous injuries
(e.g., needlesticks), although mucocutaneous (e.g., spray or splashes to
the eyes or mouth) and direct contact of infected blood with nonintact
skin are also routes of exposure. These potential infections, like
healthcare-associated infections, also appear to be tied to nurses'
working conditions. In a cross-sectional study of >1,500 nurses employed
on 40 units in 20 hospitals, poor organizational climate and high
workloads were associated with 50% to 200% increases in the likelihood
of needlestick injuries and near-misses among hospital nurses (3).
Emerging infectious diseases and outbreaks of recognized contagious
illnesses have highlighted other concerns about the safety of healthcare
workers. For example, much of the worldwide severe acute respiratory
syndrome (SARS) outbreak was hospital-based, and healthcare workers made
up a large proportion of cases, accounting for 37% to 63% of suspected
SARS patients in highly affected countries (35). In many countries,
nurses were the largest single group affected by SARS (36). During the
Toronto outbreak, patient care activities commonly conducted by critical
care nurses, such as manipulating oxygen masks and suctioning infected
patients, were significantly associated with SARS infection (37). In the
event of an influenza pandemic, healthcare workers would be susceptible.
During an outbreak of parainfluenza in a intermediate care nursery, 16
(25%) of 65 staff members reported symptoms of respiratory illness (38).
These threats to safety of the nurse and other essential healthcare
workers are of concern for many reasons.
First, a trained, qualified healthcare workforce is necessary to
respond and care for the public in the event of an outbreak. Staffing
issues and hospital organization problems are believed to have
complicated the containment of the SARS crisis in Toronto. Staffing
shortages, especially of nurses, have been identified as one of the
major factors expected to constrain hospitals' ability to deal with
possible future threats (4). Without adequate numbers of trained
hospital employees to implement effective infection control procedures,
such as hand hygiene and proper isolation procedures, emergency
departments and hospital wards can easily become the venues where the
spread of epidemics occurs.
Second, the perception of unsafe working conditions both for the
patient and the worker may actually hinder recruitment and retention of
qualified staff. In a American Nurses Association survey of RNs (N =
7,353), 88% of respondents reported health and safety concerns related
to work, 75% felt the quality of nursing care had declined in their work
setting in the past 2 years, and 92% of those respondents related these
concerns to inadequate staffing. Furthermore, >70% of respondents
indicated concerns about the acute and chronic effects of work stress
and overwork, concerns about a disabling back injury (60%), and fear of
contracting HIV or hepatitis from a needlestick injury (45%). Nurses
reported that these health and safety concerns influence their decision
to continue working in the field of nursing and the kind of nursing work
they choose to perform. Because of these concerns, nearly 55% of the
nurses surveyed would not recommend the nursing profession as a career
for their children or friends. Although the results of this survey may
not be generalizable to all nursing personnel because of the
nonprobability sampling method and inclusion of only RNs, the results
suggest that concern over safety may be contributing to hospital
personnel shortages and hindering recruitment efforts. Dissatisfaction,
burnout, and concerns about quality of care are reportedly common among
hospital nurses in five other industrialized countries (39).
Gaps in Current Knowledge
Barring unprecedented growth in the nursing workforce or unforeseen
new forces in health care that intervene to reduce burden of care in
society, the numbers of nurses will not keep pace with the demand for
services. In the coming decades, we face the prospect of fewer
professionals and more unlicensed workers in the healthcare workforce.
Decisions will have to be made about how hospitals will safely adapt to
this situation. At this time, little evidence exists on what constitutes
a safe and efficient labor force mix. Therefore, the general impact of
nurse working conditions needs to be examined. First, longitudinal
studies that track change in infection rates and other untoward
incidents over time, under different working conditions, and with
different staffing models are essential. Second, researchers need to
study how the actual care received by patients varies under different
staffing conditions at the bedside so that a better understanding of the
impact of work environments at the point of care can be gained. Finally,
since costs of care increase when patients have adverse outcomes (40)
and nurses' working conditions affect outcomes, better working
conditions could arguably save the healthcare system money. However, the
cost-benefit ratio is not known and economic analyses, which include
costs related to training, recruitment, and retention, need to be
conducted.
Implications for Policy
Policy solutions for nurse staffing fall into two general categories:
1) incentives and funding for various parties to increase the supply of
nurses and 2) employer and hospital regulatory approaches. Although
scholarships, loan forgiveness schemes, and funding of new nursing
school student slots may be helpful, these policies are unlikely to
overcome the long-standing, complex nature of the difficulties in
recruiting sufficient newcomers to the nursing profession and then
retaining a qualified workforce.
In the United States, regulatory approaches by the states have
included prohibiting mandatory overtime for nurses (nine states with
regulations), holding hospitals accountable for developing and
implementing valid staffing plans (seven states), and setting minimum
staffing ratios (one state). Regulating minimum nurse-patient ratios has
received much attention, despite critiques from the hospital industry
that insufficient data exist to credibly set minimum safe staffing
levels. California was the first state to implement hospitalwide minimum
nurse-patient ratios. The effects of this regulation need to be
carefully examined. Although nursing services are positively correlated
with patient outcomes, controversy exists over what constitutes an
optimal staffing ratio, and little empirical evidence is available on
which to base these decisions.
Staffing levels for bedside nurses are not the only critical resource
involved in decreasing risks for healthcare-associated infections,
occupational injuries, and infections. Also important is determining the
critical mass of infection control and occupational health professionals
needed for surveillance, identification of departures from sound
practices, and ongoing education of healthcare workers. Policies aimed
at ensuring the availability of training programs on all aspects of
patient and worker safety are needed, as is the availability of
appropriate supplies to prevent unnecessary infections among patients
and nurses.
Conclusions
Nursing is a predominately female occupation in which the working
conditions are often poor. Such conditions contribute to recruitment and
retention problems. Together with demographic changes, the result is a
shortage of qualified nurses. Mounting evidence demonstrates that the
lack of an adequate supply of qualified nurses is a global public safety
issue that may require a multipronged policy approach. Monitoring and
improving the working conditions of nurses are likely to improve the
quality of health care by decreasing the incidence of many infectious
diseases, assisting in retaining qualified nurses, and encouraging men
and women to enter the profession. Further research is needed to
understand how best to protect the patient as well as the healthcare
worker. Changes in the workforce will have implications for infectious
disease, infection control, and occupational health professionals with a
need for much more thorough training of nonprofessionals in critical
practices.
P.W.S.'s work was supported by AHRQ, R01 HS13114.
Dr. Stone is an assistant professor at Columbia University School of
Nursing. Her research interests include the assessment of cost and
quality outcomes related to nursing care delivery.
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Table. Summary of studies on nurse staffing and healthcare-associated
infectionsa
Investigator
Sample
Findings
Outbreak investigations
Anderson et al. (17)
36-bed neonatal ICU; 8 cases
During MRSA outbreak, 42% staff untrained, up to 62% from outside
facility
Archibald et al. (28)
1 pediatric ICU; 43 patients
Decrease 2 infections/1,000 patient days for each unit increase in RN
h: patient-day ratiob
Fridkin et al. (25)
230-bed VA center; 170 patients
Patient-nurse ratio increased during BSI outbreakc
Harbarth et al. (22)
15-bed neonatal ICU; 8 cases
Enterobacter cloacae outbreak terminated after decrease workload
Vicca (23)
1 adult unit; 50 cases
MRSAb cases associated with increase workload, decrease RN-patient
ratio
Prospective studies
Alonso-Echanove et al. (16)
8 ICUs; 4,535 patients
Float RNs >60% central venous catheter days increased risk for BSId
Haley et al. (26)
85-bed neonatal ICU; 76 infants
MRSA infections increased within 1 month of worsening workloadc
Robert et al. (21)
20-bed surgical ICU; 28 cases
BSI associated with lower regular nurse-patient and higher pooled
staff-patient ratiosb
Retrospective studies
Amaravadi et al. (19)
32 hospitals; 353 patients
Night nurse-patient ratio <1:2 associated with pneumoniac and BSIc
Arnow et al. (27)
1 burn unit; 147 patients
New cases MRSAb paralleled number of overtime h and number of shifts
by outside staff
Knauf et al. (30)
502 hospitals
Pneumonia,c postoperative infection,c UTIc associated with low RN h
and skill mix
Kovner et al. (15)
530–570 hospitals; 10 states
Increase nurse h per adjusted patient day associated with decreased
pneumoniac
Kovner & Gergen (24)
589 hospitals; 1,993 patients
Increase RN FTEs associated with decreased UTIb and pneumoniab
Lichtig et al. (20)
1,575 hospitals
Pneumonia,b postoperative infection,b UTIb associated with low RN
skill mix
Needleman et al. (29)
799 hospitals; 6,180,628 patients
Higher proportion RN h, higher RN h per day resulted in decreased
UTIb
Stegenga et al. (18)
44-bed pediatric unit; 2,929 admissions
<10.5 nurse h per patient day resulted in increased gastrointestinal
infectionsc
aHAI, healthcare-associated infections; RN, registered nurse; MRSA,
methicillin-resistant Staphylococcus aureus; BSI, bloodstream infection;
UTI, urinary tract infection; VA, Veterans Administration; ICU,
intensive care unit; FTE, full-time equivalent.
bSignificant at <0.005.
cSignificant at <0.05.
dSignificant at 0.01.
1A version of this report was presented at the International
Conference on Women and Infectious Diseases, Atlanta, GA, February
27–28, 2004.