Margaret Pass

Hospitalizations and Deaths Due to Salmonella Infections, FoodNet, 1996–1999

Nontyphoidal Salmonella causes a higher proportion of food-related deaths annually than any other bacterial pathogen in the United States. We reviewed 4 years (1996-1999) of population-based active surveillance data on laboratory-confirmed Salmonella infections from the Emerging Infections Programs Foodborne Diseases Active Surveillance Network (FoodNet), to determine the rates of hospitalization and death associated with Salmonella infection. Overall, 22% of infected persons were hospitalized, with the highest rate (47%) among persons aged >60 years. Fifty-eight deaths occurred, for an estimated annual incidence of 0.08 deaths/100,000 population. These deaths accounted for 38% of all deaths reported through FoodNet from 1996 through 1999, and they occurred primarily among adults with serious underlying disease. Although Salmonella infection was seldom listed as a cause of death on hospital charts and death certificates, our chart review suggests that Salmonella infection contributed to these deaths.

Recurrent Invasive Pneumococcal Disease in Individuals with Human Immunodeficiency Virus Infection

The proportion of relapses and reinfections that are potentially preventable by vaccine in human immunodeficiency virus (HIV)-infected persons with recurrent pneumococcal disease is unknown. Isolates from HIV-infected individuals from Baltimore with recurrent pneumococcal invasive disease were collected from 1 January 1995 through 31 December 2000. Serotyping and pulsed-field gel electrophoresis were performed. From 1 January 1995 through 31 December 1998, 14.9% (404/2717) of those who had a pneumococcal infection were HIV infected. The recurrence rate among HIV-infected individuals was 6.4-fold higher than that among individuals without HIV infection (P<.01). Among recurrent infections in 41 individuals, there were 42 reinfections and 6 relapses. All relapses and 91% (70/77) of reinfections were due to serotypes covered by the 23-valent pneumococcal polysaccharide vaccine. Reinfection was more common than relapse among HIV-infected individuals with recurrent pneumococcal disease. Although a substantial proportion of recurrent pneumococcal infections was potentially preventable by vaccine, creating an effective vaccine may be challenging for this population.

Aggregated Antibiograms and Monitoring of Drug-Resistant Streptococcus pneumoniae

Community-specific antimicrobial susceptibility data may help monitor trends among drug-resistant Streptococcus pneumoniae and guide empiric therapy. Because active, population-based surveillance for invasive pneumococcal disease is accurate but resource intensive, we compared the proportion of penicillin-nonsusceptible isolates obtained from existing antibiograms, a less expensive system, to that obtained from 1 year of active surveillance for Georgia, Tennessee, California, Minnesota, Oregon, Maryland, Connecticut, and New York. For all sites, proportions of penicillin-nonsusceptible isolates from antibiograms were within 10 percentage points (median 3.65) of those from invasive-only isolates obtained through active surveillance. Only 23% of antibiograms distinguished between isolates intermediate and resistant to penicillin; 63% and 57% included susceptibility results for erythromycin and extended-spectrum cephalosporins, respectively. Aggregating existing hospital antibiograms is a simple and relatively accurate way to estimate local prevalence of penicillin-nonsusceptible pneumococcus; however, antibiograms offer limited data on isolates with intermediate and high-level penicillin resistance and isolates resistant to other agents.

Nosocomial Malaria and Saline Flush

An investigation of malaria in a US patient without recent travel established Plasmodium falciparum molecular genotype identity in 2 patients who shared a hospital room. P. falciparum can be transmitted in a hospital environment from patient to patient by blood inoculum if standard precautions are breached.

Distribution of penicillin-nonsusceptible pneumococcal clones in the Baltimore metropolitan area and variables associated with drug resistance

We assessed the distribution of the clonal groups (as determined by pulsed-field gel electrophoresis) of penicillin-nonsusceptible Streptococcus pneumoniae that caused invasive pneumococcal infection in the Baltimore metropolitan area during 1995 and 1996. Although S. pneumoniae caused invasive disease in individuals from a variety of demographic groups and locations, strains isolated during the season in which respiratory infections are most common were more likely to be from clonal groups associated with penicillin resistance than from other groups.