Calculating the Age Distributions and Reproduction Numbers (R0) of Infection with Enteric Pathogens among Children in Low- and Middle-Income Country Settings. Open Access

Sivakumar, Ritesh (Spring 2024)

Permanent URL: https://etd.library.emory.edu/concern/etds/c534fq269?locale=en
Published

Abstract

Diarrheal diseases are both common and deadly to children, especially in developing countries. With the relatively successful rotavirus vaccination program, there have been efforts to replicate that success in other common enteric pathogens. Since vaccines can be expensive and arduous to develop and administer, modeling their impact and implementation can alleviate expenses and effort. For models to be accurate, the parameters used to make up those models need to be as empirically valid as possible. The primary goal of this study was to obtain empirically reliable values for R0 from the average age of first infection, for eight pathogens (rotavirus, norovirus, Shigella, ETEC, adenovirus, astrovirus, Campylobacter, and Cryptosporidium) in eight countries (Bangladesh, Brazil, India, Nepal, Peru, Pakistan, South Africa, and Tanzania). The data was obtained from the Malnutrition and Enteric Disease Study (MAL-ED) dataset, and median ages of first infection were calculated. We saw that the median age of first infection was quite young, with ETEC at 210 days, norovirus at 213 days, Campylobacter at 267 days, adenovirus at 274 days, astrovirus at 306 days, rotavirus at 456 days, Shigella at 461 days, and Cryptosporidium at 520 days. Using these age distributions, R0 was calculated with the following formula (R0 = L/A) where L = average life expectancy and A = average age at first infection. Based on this formula, we saw large R0 values for each of these pathogens. Cryptosporidium at 48, Shigella at 54, Rotavirus at 55, astrovirus at 82, adenovirus at 91, Campylobacter at 94, and norovirus and ETEC over 100. The young average age of first infection and large R0’s show that these pathogens are incredibly infectious and are infecting children early in life in these settings. These values will be useful for parameterization of models studying these pathogens and their control through various interventions.

Table of Contents

Introduction – Page 1

Methods – Page 4

Results – Page 6

Discussion – Page 11

References – Page 15

Appendix – Page 19

About this Master's Thesis

Rights statement
  • Permission granted by the author to include this thesis or dissertation in this repository. All rights reserved by the author. Please contact the author for information regarding the reproduction and use of this thesis or dissertation.
School
Department
Subfield / Discipline
Degree
Submission
Language
  • English
Research Field
Keyword
Committee Chair / Thesis Advisor
Committee Members
Last modified

Primary PDF

Supplemental Files