Hospital-based surveillance of invasive pneumococcal disease among young children in urban Nepal.

BACKGROUND: Streptococcus pneumoniae is a leading cause of pneumonia and meningitis in young children. Before implementation of the pneumococcal conjugate vaccine in developing countries, there is an urgent need to provide regional epidemiological data on pneumococcal disease. The aims of this study were to determine the prevalence and serotype distribution of invasive pneumococcal disease among young children hospitalized in urban Nepal. METHODS: Children aged 2 months to 5 years who were admitted to Patan Hospital, Kathmandu, with fever and/or suspected pneumonia, meningitis, or bacteremia were recruited. Blood culture specimens were collected from all participants. In cases of suspected meningitis, cerebrospinal fluid specimens were cultured and were tested for S. pneumoniae antigen. RESULTS: A total of 885 children were recruited during the 21-month study period. Of these, 76 (9%) had meningitis and 498 (56%) had pneumonia, on the basis of clinical criteria. Radiographically confirmed pneumonia occurred in 354 (40%), and probable or definite meningitis occurred in 47 (5%). S. pneumoniae was isolated in specimens from 17 (2%) of the children. Serotypes 1 and 12A were isolated most frequently, and only 1 of 17 isolates had a serotype contained in the currently available 7-valent pneumococcal conjugate vaccine. CONCLUSIONS: More than 60% of children aged <5 years who were admitted with fever and/or suspected invasive bacterial disease in urban Nepal had the clinical syndromes of meningitis and/or pneumonia. A new generation of pneumococcal vaccines that prevent infection with a broader range of serotypes may be necessary to most effectively control pneumococcal disease in young children in Kathmandu.

Bloodstream infection among children presenting to a general hospital outpatient clinic in urban Nepal.

BACKGROUND: There are limited data on the etiology and characteristics of bloodstream infections in children presenting in hospital outpatient settings in South Asia. Previous studies in Nepal have highlighted the importance of murine typhus as a cause of febrile illness in adults and enteric fever as a leading bacterial cause of fever among children admitted to hospital. METHODS: We prospectively studied a total of 1084 febrile children aged between 2 months and 14 years presenting to a general hospital outpatient department in Kathmandu Valley, Nepal, over two study periods (summer and winter). Blood from all patients was tested by conventional culture and by real-time PCR for Rickettsia typhi. RESULTS: Putative etiological agents for fever were identified in 164 (15%) patients. Salmonella enterica serovar Typhi (S. Typhi) was identified in 107 (10%), S. enterica serovar Paratyphi A (S. Paratyphi) in 30 (3%), Streptococcus pneumoniae in 6 (0.6%), S. enterica serovar Typhimurium in 2 (0.2%), Haemophilus influenzae type b in 1 (0.1%), and Escherichia coli in 1 (0.1%) patient. S. Typhi was the most common organism isolated from blood during both summer and winter. Twenty-two (2%) patients were PCR positive for R. typhi. No significant demographic, clinical and laboratory features distinguished culture positive enteric fever and murine typhus. CONCLUSIONS: Salmonella infections are the leading cause of bloodstream infection among pediatric outpatients with fever in Kathmandu Valley. Extension of immunization programs against invasive bacterial disease to include the agents of enteric fever and pneumococcus could improve the health of children in Nepal.

The burden of vaccine-preventable invasive bacterial infections and pneumonia in children admitted to hospital in urban Nepal.

BACKGROUND: Protein-polysaccharide vaccines have made a significant impact on the burden of disease caused by encapsulated bacteria such as Streptococcus pneumoniae, Haemophilus influenzae, Neisseria meningitidis, and have the potential to do so for Salmonella Typhi. Nepal is one of many resource-poor nations with limited information on the epidemiology of childhood infections caused by these pathogens. METHODS: Over a 21-month period, we studied children aged ≤12 years admitted to an urban hospital in Nepal with suspected bacteremia, meningitis, or pneumonia. Patan Hospital is a non-profit hospital with the second largest pediatric unit in the Kathmandu Valley. RESULTS: Of 2039 children enrolled in the study, 142 (7.5%) included in the analysis had positive blood cultures. The agents of enteric fever, Salmonella Typhi and Salmonella Paratyphi, accounted for 59/142 (42%) of all bacteremias and were the most frequently cultured pathogens in children ≥1 year of age. S. pneumoniae was isolated in 16% of positive blood cultures and was the most common cause of bacteremia in children <1 year of age. Pneumonia accounted for 51% of admissions in children ≥2 months, with 44% of these children having radiographically defined primary endpoint pneumonia. S. pneumoniae was the most commonly identified pathogen in cases of pneumonia and meningitis. The S. pneumoniae serotype distribution indicated that the 10-valent and 13-valent pneumococcal conjugate vaccines would cover 44% and 47%, respectively, of all S. pneumoniae cultured from blood or cerebrospinal fluid (CSF) isolates and 62% and 67%, respectively, of isolates associated with pneumonia. H. influenzae type b was isolated infrequently from blood or CSF cultures, but is likely to be more important as a cause of pneumonia. CONCLUSIONS: The data on the burden of invasive bacterial infections and pneumonia from this study suggest that vaccines in development against Salmonella Typhi and the pneumococcus have the potential to significantly improve the health of children in Nepal.