The Etiology of Pneumonia in Zambian Children: Findings From the Pneumonia Etiology Research for Child Health (PERCH) Study.

Lawrence Mwananyanda,Somwe Wa Somwe,James Mwansa,Melissa M Higdon,Geoffrey Kwenda,Donald M Thea,Christine Prosperi,James Chipeta,Meredith Haddix,Phil Seidenberg,Katherine L O’Brien,Musaku Mwenechanya,Justin M Mulindwa,Maria Deloria Knoll,Daniel R Feikin,Laura L Hammitt,David R Murdoch

doi:10.1097/inf.0000000000002652

Abstract

Childhood pneumonia in developing countries is the foremost cause of morbidity and death. Fresh information on etiology is needed, considering the changing epidemiology of pneumonia in the setting of greater availability of effective vaccines, changing antibiotic use and improved access to care. We report here the Zambia site results of the Pneumonia Etiology Research for Child Health study on the etiology of pneumonia among HIV-uninfected children in Lusaka, Zambia. We conducted a case-control study of HIV-uninfected children age 1-59 months admitted with World Health Organization-defined severe or very severe pneumonia to a large tertiary care hospital in Lusaka. History, physical examination, chest radiographs (CXRs), blood cultures and nasopharyngeal/oropharyngeal swabs were obtained and tested by polymerase chain reaction and routine microbiology for the presence of 30 bacteria and viruses. From age and seasonally matched controls, we tested blood and nasopharyngeal/oropharyngeal samples. We used the Pneumonia Etiology Research for Child Health integrated analysis to determine the individual and population etiologic fraction for individual pathogens as the cause of pneumonia. Among the 514 HIV-uninfected case children, 208 (40.5%) had abnormal CXRs (61 of 514 children were missing CXR), 8 (3.8%) of which had positive blood cultures. The overall mortality was 16.0% (82 deaths). The etiologic fraction was highest for respiratory syncytial virus [26.1%, 95% credible interval (CrI): 17.0-37.7], Mycobacterium tuberculosis (12.8%, 95% CrI: 4.3-25.3) and human metapneumovirus (12.8%, CrI: 6.1-21.8). Childhood pneumonia in Zambia among HIV-uninfected children is most frequently caused by respiratory syncytial virus, M. tuberculosis and human metapneumovirus, and the mortality remains high.

Highlights

Childhood pneumonia in developing countries is the foremost cause of morbidity and death
Results of the PERCH integrated analysis (PIA) analysis showed that respiratory syncytial virus (RSV) was the most common pathogen (EF: 26.1%, 95% credible interval (CrI): 17.0–37.7) among children with CXR-confirmed pneumonia and had double the etiologic fraction (EF) of most common pathogens, M. tuberculosis (12.8%, 95% credible interval (95% CrI): 4.3–25.3) and human metapneumovirus (HMPV) (12.8%, CrI: 6.1–21.8) (Fig. 2, Supplemental Digital Content 8, http://links.lww.com/INF/D857)
The clinical and etiology findings described here reflect the presentation of community-acquired childhood pneumonia among HIV-uninfected children in the setting of a typical sub-Saharan African city, Lusaka, Zambia—an impoverished, densely populated, urban population with high HIV and M. tuberculosis prevalences and limited access to high-quality health care

Summary

PERCH Site Results

Lawrence Mwananyanda, MD,*† Donald M. Thea, MD, MSc,* James Chipeta, MBChB, PhD,‡§ Geoffrey Kwenda, PhD,¶ Justin M. Mulindwa, MMed,‡ Musaku Mwenechanya, MBChB, MMed,‡ Christine Prosperi, ScM,║ Melissa M. Higdon, MPH,║ Meredith Haddix, MPH,║ Laura L. Hammitt, MD,║ Daniel R. Feikin, MD,║ David R. Murdoch, MD,**†† Katherine L. O’Brien, MD, MPH,║ Maria Deloria Knoll, PhD,║

Background

Methods

MATERIALS AND METHODS

RESULTS

DISCUSSION