To describe the use of zanamivir during an influenza A outbreak.

Residents of a 176-bed long-term-care facility for the elderly in Newmarket, Ontario, Canada, 90% of whom received influenza vaccine in the fall of 1998.

When respiratory illness due to influenza A was confirmed, infection control measures and amantadine prophylaxis were initiated. Despite these measures, transmission of influenza A continued.

Zanamivir inhalations, 10 mg daily for prophylaxis and 10 mg twice daily for treatment of influenza.

There were 13 definite and 66 probable outbreak-associated cases of influenza A. Twelve (15%) cases developed pneumonia, 7 (9%) were hospitalized, and 2 (2.6%) died. All 12 culture-positive cases yielded influenza A/Sydney/H3N2/05/97-like virus, a 1998/99 vaccine component. The three isolates obtained prior to the initiation of amantadine were amantadine-susceptible; all nine obtained after prophylaxis was instituted were amantadine-resistant. One hundred twenty-nine (92%) of 140 residents who were offered zanamivir accepted it and were able to attempt inhalations. Of these 129, 78% (100) had no difficulty in complying with inhalations. Difficulty with inhalations was associated with decreased functional and mental status. Fifteen (58%) of 26 residents fully dependent in activities of daily living had difficulty compared to 14 (14%) of 100 others (P<.001). Twenty-two (45%) of 49 residents not oriented to person, place, or time had difficulty compared to 7 (10%) of 77 others (P<001). In the 2 weeks after zanamivir prophylaxis, only 2 new cases of respiratory illness occurred, neither confirmed as influenza. No side effects were identified in 128 zanamivir-treated residents.

A minority of nursing home residents have difficulty following instructions for zanamivir inhalations. Zanamivir was well tolerated, and its use was temporally associated with termination of an outbreak that amantadine had failed to control.

To evaluate collaborative efforts and intervention strategies by peer-review organizations (PROs) and long-term-care facilities (LTCFs) for improving pneumococcal vaccination rates among residents of LTCFs.

Prospective, before-after quality improvement project.

133 LTCFs in Alaska, Idaho, Montana, and Wyoming.

All residents of participating LTCFs.

Baseline pneumococcal vaccination rates were determined by medical-record review, self-reporting by patient or family members, and review of Medicare claims information. Remeasurement of vaccination rates was accomplished from documentation of vaccination of eligible residents by each LTCF.

133 LTCFs with 7,623 residents from Alaska, Idaho, Montana, and Wyoming participated in this quality-improvement project. This accounted for 41% (133/321) of the potential nursing homes and resident population in the participating states. Baseline overall vaccination rates were 40% (3,050/7,589). The overall vaccination rate improved to 75% (5,720/7,623, P<.001). The number of facilities meeting the Healthy People 2000 vaccination goal of 80% improved from 18% (24/133) to 62% (83/133, P<.001). Initial use of chart stickers and implementation of standing orders led to similar increases in vaccination rates, but the standing-order strategy required commitment of fewer PRO resources at a statewide level. Remeasurement of vaccination rates in a subset of participating Idaho LTCFs 1 year after initial vaccination efforts demonstrated a sustained vaccination rate of 70% in facilities enforcing a standing-order policy.

Simple and straightforward vaccination strategies implemented in LTCFs over a short period of time can have a significant impact on vaccination rates. Collaborative efforts between state PROs and LTCFs enhance implementation of these strategies and can result in the achievement of national vaccination objectives. Standing orders appear to be one intervention effective in sustaining successful vaccination efforts. Regardless of the specific interventions employed, PROs played a significant role in facilitating vaccination program development and intervention implementation.

To describe a pneumonia outbreak caused by Streptococcus pneumoniae among residents of a home for the aged and to review contemporary pneumococcal outbreaks.

Epidemiological investigation.

S pneumoniae isolates were serotyped and analyzed by pulsed-field gel electrophoresis. Paired sera were tested for antibodies to pneumococcal surface adhesin A protein (PsaA, a 37-kDa cell-wall protein). Pneumococcal outbreaks reported in the last decade in English were reviewed.

Pneumonia developed in 18 of 200 residents. In 11 (61%), a pneumococcal etiology was demonstrated. S pneumoniae, serotype 4, was isolated from the blood cultures of 3 patients; all isolates were indistinguishable by pulsed-field gel electrophoresis. Pneumococcal involvement was established in 2 by sputum culture and latex agglutination of parapneumonic fluid and in 6 others by a twofold rise in optical density of serum antibody reactive to PsaA. Pneumococcal immunization had not previously been received by any patient; mortality was 22%. No additional cases were noted following administration of pneumococcal vaccine and antibiotic prophylaxis with penicillin or erythromycin. Twenty-six outbreaks of invasive pneumococcal disease since 1990 were reviewed. Twelve occurred in the United States, and serotypes 23F, 14, and 4 accounted for 8 (67%) of 12 outbreaks. All confirmed serotypes in US outbreaks are included in the 23-valent vaccine. More than one half of pneumococcal outbreaks worldwide involved elderly persons in hospitals or long-term-care facilities.

A pneumococcal pneumonia outbreak occurred among unvaccinated residents of a residential facility for the aged. Institutionalized elderly persons are at risk of outbreaks of pneumococcal disease and should be vaccinated.

To determine the roles of “colonization pressure,” work load or patient severity in patient acquisition of methicillin-resistant Staphylococcus aureus (MRSA) in intensive care units (ICUs).

Prospectively collected data from October 1996 through December 1998.

A 12-bed medical ICU in a university-affiliated general hospital.

Patients with risk factors for MRSA admitted to the ICU were screened within 72 hours of admission and weekly thereafter. MRSA was considered imported if detected during the first 72 hours of admission and nosocomial if detected only thereafter. Three screening strategies were used on admission during three consecutive periods.

The unit of time chosen for measurements was the week. Weekly colonization pressure (WCP) was defined as the number of MRSA-carrier patient-days/total number of patient-days. Patient severity (number of deaths, Simplified Acute Physiologic Score [SAPS] II), work load (number of admissions. Omega score), and colonization pressure (number of MRSA carriers at the time of admission, WCP) were compared with the number of MRSA-nosocomial cases during the following week.

Of the 1,016 patients admitted over 116 weeks, 691 (68%) were screened. MRSA was imported in 91 (8.9%) admitted patients (13.1% of screened patients) and nosocomial in 46 (4.5%). The number of MRSA-nosocomial cases was correlated to the SAPS II (P=.007), the Omega 3 score (P=.007), the number of MRSA-imported cases (P=.01), WCP (P<.0001), and the screening period (P<.0001). In multivariate analysis, WCP was the only independent predictive factor for MRSA acquisition (P=.0002). Above 30% of WCP, the risk of acquisition of MRSA was approximately fivefold times higher (relative risk, 4.9;95% confidence interval, 1.2-19.9; P<.0001).

Acquisition of MRSA in ICU patients is strongly and independently influenced by colonization pressure.

The purpose of the study was to determine the incidence and risk factors for the acquisition of methicillin-resistant Staphylococcus aureus (MRSA) in our community.

This study used a cross-sectional design to assess patients colonized or infected with MRSA.

The study population consisted of residents of London, Ontario, Canada, who were identified as MRSA-positive for the first time in 1997.

All acute- and chronic-care hospitals, long-term healthcare facilities, and community physicians' offices in the city of London participated in the study.

Incidence of MRSA in the community, risk factors for acquisition, especially previous hospitalization over a defined period, and strain type were evaluated.

In 1997, 331 residents of London were newly identified as MRSA-positive, representing an annual incidence of 100/100,000 persons (95% confidence interval, 88.8-110.7). Thirty-one (9.4%) individuals were not healthcare-facility patients in the previous month, and 11 (3.3%), 10 (3.0%), and 6 (1.8%) individuals had no such contact in the previous 3, 6, and 12 months, respectively. One hundred seventy-seven strains, including five of the isolates from patients with no healthcare-facility contact in the previous year, were typed. One hundred sixty (90.3%) of these isolates, including all typed strains from patients with no healthcare facility contact, belonged to a single clone.

These findings demonstrate that the incidence of MRSA is higher than previously reported and that hospital contact is the single most important risk factor for the acquisition of MRSA in our community. Screening for MRSA in previously hospitalized patients at the time of hospitalization may reduce nosocomial spread and indirectly reduce the incidence of MRSA in the community.