This document presents a compartmental model for modeling the spread of Chlamydia, a sexually transmitted disease. The model divides a population into susceptible, incubation, infected, and recovered compartments. The document provides background on Chlamydia, its symptoms and effects. It then describes the model and parameters used. Results are presented showing the disease trend over time for different incubation period lengths. The model effectively demonstrated how a longer incubation period allows the disease to spread for a longer period before declining.

1. +
Compartmental Model for Chlamydia, a Sexually
Transmitted Disease
Pérez-Ayala, Michelle C.1, Figueroa-Monsanto, Héctor L.2 and Cruz-Aponte, Maytee3
Department of Biology, University of Puerto Rico at Cayey1, Department of Chemistry,
University of Puerto Rico at Cayey2 and Department of Mathematics-Physics, University of
Puerto Rico at Cayey3

2. +
Biological Disease: Chlamydia
 Chlamydia
 Sexually transmitted disease (STD)
 Direct contact with any area of the body with the bacterium
Chlamydia trachomatis
 Child Birth
 Chlamydia is the most common sexually transmitted
disease (STD) in the world (Siam, 2012)
 Chlamydia trachomatis
 Incubation period: 5-21 days
www.allposters.com

3. +
Chlamydia in Puerto Rico and Worldwide
Selected Data
• Puerto Rico – Individuals between de ages of 20-24
are the most susceptible (Department of Health, 2012)
• Worldwide – People that are 25 years old or less are
the most susceptible (Occhionero et al. 2015)
www.shutterstock.comwww.banderasboricuas.com

4. + Susceptibility and
Disease Symptoms
 Females
 Blood flow between periods
 Pain: periods, sex, abdomen, and
urination
 Vagina itch
 Males
 Pain: testicles and urination
 Penis: swelling, pain, burn, itch,
and transparent discharge
 Urethritis: 55%
www.newattitudes.co.uk imgkid.com

5. +
Problems of C. trachomatis
 Males
 Al-Mously (2015) studied the effect of Chlamydia trachomatis on
sperms to detect if the bacterium caused sub-fertility in men
 Viability and motility cannot be prevented by in vitro fertilization
 Females
 De Borborema-Alfaia (2013) study reflected a 3.4 % of premature
membrane rupture in Brazilian women around the age of 30 or less
 Symptoms are not commonly reflected
 Combined with C. psittaci could result in trachoma (Nittler et al. 2014)

6. +
Treatments
Antibiotics
Recovered
people could be
susceptible
again
www.survivingcipro.com

7. +
Hypothesis
The compartmental model of chlamydia will differ
significantly from the basic SIR model, due to the
addition of the incubation compartment affecting
the flow of the disease in a given population

8. +
Objective
 Create and use a compartmental model to
demonstrate the tendency of the disease with
susceptible, incubation period, infected, re-infected
and recovered individuals from a population of 100
people
 Create precautions
 Lessen the number of infected and re-infected
individuals
 Avoid infertilities

9. +
Methodology:
Chlamydia Parameters and Model
 Modified SIR Model
 Susceptible, Incubation Period, Infected and Recovered
 The compartmental model shows the flow of the
disease
www.sunflowerhospital.in
www.nature.com
www.genitaldischarge.comwww.fancyicons.com

10. + Schematic of disease dynamics:
Mathematical Model
S
E
I
R
α SI/N
βE
γI
μR

11. + Schematic of disease dynamics:
Parameters

12. +
Results:
Chlamydia Disease Trend during an
Incubation Period of 13 Days
S = Susceptible Individuals
E = Incubation Period
I = Infected Individuals
R = Recovered Individuals

13. +
Chlamydia Disease Trend during an
Incubation Period of
5 Days
S = Susceptible Individuals
E = Incubation Period
I = Infected Individuals
R = Recovered Individuals

14. +
Conclusion
The hypothesis was proven
The results showed that by increasing the
incubation period from 5 days to 13 days
People were susceptible for a longer period of
time: 55 days
The amount of infected and recovered
individuals that maintained in equilibrium
diminished

15. +
Future Works
This model could be used for another
assigned population with a different time
range
 This combined with the problems (e.g. infertility)
mentioned about Chlamydia to create awareness

16. +
Cited Literature
 Al-Mously N, Eley A. 2015. Transient exposure to Chlamydia
trachomatis can induce alteration of sperm function which cannot be
stopped by sperm washing. Middle East Fertility Society Journal 20,
48-53. doi:10.1016/j.mefs.2014.04.003.
 Borges V, Gomes JP. 2015. Deep comparative genomics among
Chlamydia trachomatis lymphogranuloma venereum isolates
highlights genes potentially involved in pathoadaptation. Infection,
genetics and Evolution 32, 74-88. doi:10.1016/j.meegid.2015.02.026.
 De Borborema-Alfaia APB, de Lima Freitas NS, Filho SA, Borborema-
Santos CM. 2013. Chlamydia trachomatis infection in a simple of
northern Brazilian pregnant women: prevalence and prenatal
importance. Braz J Infect Dis 17(5):545-550.
doi:10.1016/j.bjid.2013.01.014.
 Departamento de Salud. 2012. Datos de Puerto Rico.
http://www.estadisticas.gobierno.pr/iepr/LinkClick.aspx?fileticket=RVO
VIk8ka1A%3D&tabid=186.

17. +
Cited Literature
 Knittler MR, Berndt A, Böcker S, Dutow P, Hänel F, Heuer D, Kägebein
D, Klos A, Koch S, Liebler-Tenorio E, Ostermann C, Reinhold P, Saluz
HP, Schöfl G, Sehnert P, Sachse K. 2014. Chlamydia psittaci: New
insights into genomic diversity, clinical pathology, host-pathogen
interaction and anti-bacterial immunity. International Journal of Medical
Microbiology 304, 877-893. doi:10.1016/j.ijmm.2014.06.010.
 Occhionero M, Paniccia L, Pedersen D, Rossi G, Mazzucchini H,
Entrocassi A, Vaulet LG, Gualtieri V, Fermepin MR. 2015. Prevalencia
de la infección por Chlamydia trachomatis y factores de riesgo de
infecciones transmisibles sexualmente en estudiantes universitarios.
Rev Argent Microbiol 47(1): 9-16. doi:10.1016/j.ram.2014.11.003.
 Siam EM, Hefzy EM. 2012. The relationship between antisperm
antibodies prevalence and genital Chlamydia trachomatis infection in
women with unexplained infertility. Middle East fertility Society Journal
(2012) 17, 93-100. doi:10.1016/j.mefs.2011.09.003.

18. +
Acknowledgments
 Dr. Maytee Cruz-Aponte
 Danilo Pérez-Rivera
• Dr. Eneida Díaz
• Dr. Elena González
• Dr. Robert Ross