Childhood Invasive Bacterial Disease in Kathmandu, Nepal (2005-2013)

Area of Science:

• Pediatric infectious diseases
• Microbiology
• Vaccinology

Background:

• Invasive bacterial disease (IBD), including pneumonia, meningitis, and sepsis, significantly contributes to child morbidity and mortality in low-income nations.
• Understanding the epidemiology of IBD is crucial for developing effective prevention and control strategies, particularly in regions with limited healthcare resources.

Purpose of the Study:

• To analyze the serotype distribution of invasive pneumococcal disease (IPD) in children before the introduction of pneumococcal conjugate vaccines (PCV) in Kathmandu, Nepal.
• To evaluate the effectiveness of enhanced surveillance methods, including antigen and PCR testing, for identifying IBD pathogens in cerebrospinal fluid (CSF).

Main Methods:

• Data from a surveillance study of suspected community-acquired IBD in children under 15 years in Kathmandu, Nepal (2005-2013) were analyzed.
• Cerebrospinal fluid (CSF) and blood samples were cultured, and antigen and PCR testing were incorporated for enhanced pathogen detection.
• Serotype-specific distribution of invasive pneumococcal disease (IPD) was detailed.

Main Results:

• Salmonella enterica serovar Typhi (28%) and Streptococcus pneumoniae (16%) were the most prevalent pathogens isolated from blood or CSF cultures.
• The majority of identified pneumococcal serotypes were covered by 10-valent and 13-valent PCVs (73% and 78%, respectively).
• Combined antigen and PCR testing of CSF increased the identification of key pathogens (pneumococci, Haemophilus influenzae type b, meningococci) from 33 to 68 cases.

Conclusions:

• Salmonella Typhi and Streptococcus pneumoniae were the primary bacterial pathogens causing invasive disease in children in this study cohort.
• The findings indicate that current pneumococcal conjugate vaccines likely cover a significant proportion of circulating pneumococcal serotypes.
• Enhanced diagnostic methods, such as antigen and PCR testing of CSF, significantly improve the sensitivity for detecting IBD pathogens.