Emerging Infectious Disease ISSN: 1080-6059

A Dynamic Transmission Model for Predicting Trends in Helicobacter pylori and Associated Diseases in the United States

Marcia F.T. Rupnow*

, Ross D. Shachter*, Douglas K. Owens*†, and Julie Parsonnet*

Author affiliations: *Stanford University, Stanford, California, USA; †Department of Veterans Affairs Health Care System, Palo Alto, California, USA

Input variables and sources

Symbol	Description	Value	Explanation	Source
Population parameters
µ_(a)	Death rate (per person per year)	Age-specific		18
Z	Population size (persons)	200,000		Assumption
II	Birth rate (persons per year)	2,962	Derived from disease-free
			equilibrium simulation
^p_I	Proportion (%) nonsusceptible	20	Based on data from	Assumption
			developing countries
Disease parameters
^p_C	Proportion (%) of children with	5		Assumption
	antrum (vs. corpus) gastritis
^p_Y	Proportion (%) of youths with	75	Based on simulation	Assumption
	antrum (vs. corpus) gastritis
^p_A	Proportion (%) of adults with	95		Assumption
	antrum (vs. corpus) gastritis
δ□ _1C	^AGC ^{to CG}C (per person per year)	0		Assumption
___δ□ _1Y	^AGY ^{to CG}Y (per person per year)	0		Assumption
___δ□ _1A	^AGA ^{to CG}A (per person per year)	0.0010	1% progression in 10 yrs	Assumption
δ□ ₂	^AGA to DU (per person per year)	0.0046	14% progression in 32 yrs	22
___δ□ ₃	DU to CAG (per person per year)	0.0020	2% progression in 10 yrs	15
___δ□ ₄	^CGA to CAG (per person per year)	0.0112	30% progression in 32 yrs	22
___δ□ ₅	CAG to GC (per person per year)	0.0030	3% progression in 10 yrs	13
___ µ_DU	Mortality rate due to DU	0.0050		23
	(per person per year)
___ µ_GU	Mortality rate due to GU	0.0100		24
	(per person per year)
___ µ_GC	Mortality rate due to GC	0.3219	80% death in 5 yrs	25
	(per person per year)

GC = Gastric cancer; DU = Duodenal ulcer; CG = Corpus-predominant gastritis; AG = Antrum-predominant gastritis; CAG = Chronic atrophic gastritis.

¹Specific graphs can be made available to readers upon request.