New research perspectives on the

ecoepidemiology of neglected intestinal

helminthiasis in urban-marginal and rural

areas of the province of Guayas (Ecuador)

Nuevas perspectivas de Investigación sobre

Ecoepidemiología de las helmintiasis intestinales

desatendidas en zonas urbanomarginales y rurales de la

provincia del Guayas (Ecuador)

Roberto Darwin Coello-Peralta

Abstract: Neglected intestinal helminthiases are very prevalent

worldwide and represent a serious problem of: environmental

contamination (presence of feces with infective parasitic forms

dispersed in the soil), animal health and public health. This paper

explains new research perspectives on the ecoepidemiology of

neglected intestinal helminthiasis in urban-marginal and rural areas of

the province of Guayas (Ecuador). By means of an applied study with

a qualitative, quantitative, field, descriptive-prospective-analytical-

transversal approach, fecal samples of humans and their domestic

dogs from the indicated areas will be analyzed, in order to provide

information: The relationship between the environment-helminths-

and hosts, prevalence of neglected intestinal helminthiases, zoonotic

association, characterization of environmental variables, specification

of social determinants of health and generate scientific production.

Keywords: Ecoepidemiology, social determinants, environmental

parameters, epidemiological indicators, zoonotic association.

Summary

Published

Instituto Tecnológico Superior Edwards

Deming. Quito – Ecuador

Periodicity

April - June

Vol. 2, Num. 2, 2023

Dates of receipt

Received: December 29, 2022

Approved: March 30, 2023

http://centrosuragraria.com/index.php/revista

vol. 1. Num. 17. 2023.

pp. 44-51

Correspondence author

roberto.coellope@ug.edu.ec

Creative Commons License

Creative Commons License, Attribution-

NonCommercial-ShareAlike 4.0

International.https://creativecommons.org/lice

nses/by-nc-sa/4.0/deed.es

1 Director of the FCI Project on Ecoepidemiology of Neglected Intestinal Helminthiases in Urban-Marginal

and Rural Areas of the Province of Guayas, Faculty of Veterinary Medicine, University of Guayaquil (UG),

Guayaquil, Ecuador, roberto.coellope@ug.edu.ec, https://orcid.org/0000-0001-5152-2843

April - June vol. 2. Num. 2 - 2023

Resumen: Las Helmintiasis Intestinales Desatendidas son muy

prevalentes a nivel mundial y representan un serio problema de:

contaminación ambiental (presencia de heces fecales con formas

parasitarias infectivas dispersas en el suelo), salud animal y salud

pública. El presente explica, sobre las nuevas perspectivas de

investigación sobre la ecoepidemiología de las helmintiasis

intestinales desatendidas en zonas urbanomarginales y rurales de la

provincia del Guayas (Ecuador). Mediante un estudio aplicado con

enfoque cualitativo, cuantitativo, de campo, descriptivo-prospectivo-

analítico-transversal, se analizarán muestras fecales de humanos y de

sus perros domésticos de las zonas señaladas, con el fin de dar a

conocer: La relación entre el medio ambiente-helmintos-y

hospederos, prevalencia de las helmintiasis intestinales desatendidas,

asociación zoonótica, caracterización de variables ambientales,

especificación de determinantes sociales de salud y generar

producción científica.

Palabras clave: Ecoepidemiología, determinantes sociales,

parámetros ambientales, indicadores epidemiológicos, asociación

zoonótica.

1. Introduction

Ecoepidemiology is a branch of ecology, which deals with the

synanthropic interaction between the pathogen, various hosts and the

environment, which ultimately manifests with the spread of infectious

diseases (Banerjee et al., 2017).

Approximately 75% of emerging infectious diseases affecting humans

are of animal origin, and 60% of all human pathogens are zoonotic and

are a threat to public health worldwide (Bueno et al., 2015). In the case

of intestinal helminthiases, these are prevalent worldwide, especially

in developing countries with tropical and subtropical climates, and are

related to poverty (PAHO/WHO, 2021).

The most frequent intestinal helminths are A. lumbricoides, Trichuris

trichiura, Hookworm spp. (Ancylostoma and Uncinaria), H. nana, E.

vermicularis, S. stercoralis and Taenia species. Infections with these

parasites generally lead to nutritional deficiency, poor immunity,

gastrointestinal problems, mucosal leakage, lymphatic leakage and

local hemorrhages (Liyih et al., 2021); in the case of Ancylostoma

caninum it enters humans percutaneously and produces a pathology

called Larva migrans cutanea (Coello et al., 2019); and in the case of

Toxocara canis it produces 3 syndromes: visceral larva migrans

(associated with digestive, respiratory and nervous pathologies), ocular

larva migrans (associated with ocular pathology) and covert

New research perspectives on the ecoepidemiology of neglected intestinal helminthiasis in urban-

marginal and rural areas of the province of Guayas (Ecuador)

toxocariasis (associated with mild symptomatology) (Roldán et al.,

2010).

In Ecuador there are no studies on Ecoepidemiology of Neglected

Intestinal Helminthiasis in rural and urban marginal areas; therefore,

it is of great importance to carry out this study that will be of great

contribution for the epidemiological surveillance systems and for the

FCI 029 project approved by the University of Guayaquil, called:

Ecoepidemiology of Neglected Intestinal Helminthiasis in urban

marginal and rural areas of the province of Guayas.

The urban-marginal sectors under investigation have a population that

is in permanent contact with marshes, ditches, sports fields, markets,

schools, garbage dumps, dirt roads and backyard animals. The

population of the rural sectors mentioned above is in contact with rivers,

marshes, ditches, dykes, ditches, dams (where freshwater parasites can

develop), rice fields, garbage dumps, forestry, and domestic and wild

animals; however, in both sectors, most of the houses have little

infrastructure, the roads are made of dirt and there is no sewage or

potable water.

It is important to highlight that this is a multidisciplinary study, where a

problem that could be hidden is that due to the current pandemic of Covid-19,

humans and their domestic dogs in their homes, being in intimate contact with

each other due to confinement, it is likely to increase the contagion and

transmission of these parasitosis inside their homes.

2. Materials and methods

Type and Design of research:

This is an applied study with a qualitative, quantitative, field,

descriptive-prospective-analytical-cross-sectional approach.

There will be 2 urban-marginal sectors of Guayaquil: Balerio Estacio

and La Ladrillera; as well as 2 rural sectors of the Province of Guayas

which are: Loma Larga (Nobol canton) and Santa Rosa (Daule canton).

The population of the Urbano Estacio Cooperative is 32,000

inhabitants, that of the Ladrillera sector is 1607 inhabitants (Department

of Appraisal and Cadastre of the Municipality of Guayaquil, 2022), that

of Loma Larga is 1000 inhabitants (Department of Appraisal and

Cadastre of the Municipality of Nobol, 2022) and that of Santa Rosa

April - June vol. 2. Num. 2 - 2023

1450 inhabitants (According to the Department of Appraisal and

Cadastre of the Municipality of Daule, 2022). The total population in

the four zones is 36,057 inhabitants, housed in 7,212

dwellings/households. For the calculation of the sample size, the

WinEpi (2023) program was used with a confidence level of 95%,

population size 7212 (households) and a minimum expected prevalence

of 5% (Cooper et al., 1993; Moncayo et al., 2018), giving a result of 59

dwellings, where 2 samples of domestic dogs and 1 of humans will be

taken (118 samples of canines and 59 samples of humans per sector).

For the statistical treatment of the data, summaries of the quantitative

variables will be used, which will be made using the measures of central

tendency and the measures of dispersion with their corresponding

graphs.

Summaries of qualitative variables will be presented using ratios,

proportions and rates; and risk estimation will be performed using the

odds ratio. Statistical analysis will be performed using R version

1.2.5033 (Venables et al., 2022) and RStudio (RStudio Team, 2022).

Fecal samples from humans and their domestic dogs will be analyzed

to determine intestinal helminths by direct coproparasitic methods

(Fabián et al., 2003), flotation (Willis, 1921), and sedimentation using

saline solution (Fabián et al., 2003; CDC, 2021). To differentiate

Strongyloides stercoralis and Ancylostoma caninum larvae, the

modified Baermann method (Coello et al., 2019) and PCR will be

performed to confirm the presence of helminths (Avila et al., 2021). A

standardization technique for a molecular diagnostic test for

Ancylostoma caninum in canines will also be performed.

Social determinants (Number of family members, Ages of family

members, Occupation, Presence of skin, eye and other diseases,

Household infrastructure, Presence of sewerage and type of water

supply, Health system, Excreta disposal and Animal ownership) will be

measured through surveys.

Environmental parameters (Temperature, Humidity, Precipitation,

Solar Radiation, Soil Texture, Vegetation Type, Deforestation and

Fauna) will be obtained through data provided by environmental

programs such as: Weather Spark (2022), Weather Atlas (2022),

Meteored (2022), Instituto Nacional de Meteorología e Hidrología

(INAMHI) (2023); as well as through observation and soil studies,

Epidemiological indicators (Prevalence, Morbidity, Mortality) will be

determined by laboratory analysis and surveys.

New research perspectives on the ecoepidemiology of neglected intestinal helminthiasis in urban-

marginal and rural areas of the province of Guayas (Ecuador)

3. Result

1) The Ecoepidemiology of neglected intestinal helminthiasis in urban-

marginal and rural areas of the Guayas Province will be evaluated.

2) Environmental variables in the selected study localities will be

characterized.

3) The social determinants of health present in the sampling units will be

specified.

4) Identify intestinal helminths in humans and their domestic dogs present in

the study areas.

5) Epidemiological indicators in the study areas will be estimated.

6) Scientific production will be generated through scientific articles,

presentations, participation in national and international events and a doctoral

proposal on the Ecoepidemiology of Ancylostoma caninum in urban-marginal

and rural areas of the Ecuadorian Coast.

7) Development of new methodologies, processes and techniques applicable

for biomedical parasitology.

8) Generate other research.

9) Prevent outbreaks or epidemics, through talks and awareness-raising.

10) To strengthen the study of neglected parasitosis in third, fourth and fifth

level students.

11) Graduate: 3 students of Veterinary Medicine and Zootechnics of the

University of Guayaquil and Doctorate (in 5 years).

12) Holding of an International Microbiology Congress.

4. Conclusions

This is a project of the Competitive Research Fund (FCI) that was

approved by the Research Council of the Faculty of Veterinary

Medicine and Animal Husbandry, also by the Directorate of Research,

both of the University of Guayaquil, lacking the approval of the Ethics

Committee of Human Research CEISH (in process). The results

obtained will be of valuable information for the epidemiological

April - June vol. 2. Num. 2 - 2023

surveillance systems of wildlife, animal health and public health, which

will serve to establish control and prevention programs of intestinal

Helminthiasis, and avoid the spread of these parasitosis to other areas

since the areas to investigate have all the conditions for the various

biological cycles of transmission. However, Dr. Ana Lucia Ruano

Nieto, presented to SENESCYT in 2013, the National Program for the

multidisciplinary approach to neglected Parasitosis in Ecuador

(PROPAD), which was developed on a national scale and made early

and accurate diagnoses of the different types of parasites in Ecuador.

On the other hand, PAHO's Regional Program for Neglected Diseases

promotes a comprehensive approach that includes both

interprogrammatic strategies and intersectoral actions. In this context,

the guide for the formulation and implementation of Comprehensive

Plans for the Control or Elimination of Neglected Diseases was

developed with the purpose of joining efforts for the planning,

implementation, monitoring and evaluation of interventions and

programs for the prevention, control and elimination of Neglected

Infectious Diseases in the health sector.

With the above described, it is worthwhile to investigate the:

Ecoepidemiology of neglected intestinal helminthiasis in urban-

marginal and rural areas of the province of Guayas (Ecuador).

References

Banerjee M, Perasso A, Venturino E. (2017). Epidemiology and

Ecoepidemiology: Introduction tothe Special Issue. Math. Model.

Nat. Phenom, 12(2): 1-3.

Bueno R, Gouveia A, Navarro J (2015). Emerging zoonoses: Eco-

epidemiology, involved mechanisms and Public Health

Implications. Front Public Health, 3(1): 1-2.

WHO / PAHO. (2021). Neglected, tropical and vector-borne diseases.

Available at: https://www.paho.org/es/temas/enfermedades-

desatendidas-tropicales-transmitidas-por-vectores.

Liyih M, Damtie D, Tegen D. (2022). Prevalence and Associated Risk

Factors of Human Intestinal Helminths Parasitic Infections in

Ethiopia: A Systematic Review and Meta-Analysis. Scientific

World Journal: 3905963. doi: 10.1155/2022/3905963.

Coello R, Pazmiño B, Reyes E, Rodríguez E, Rodas E, Rodas K, et al.

(2019). A Case of Cutaneous Larva Migrans in a Child from

Vinces, Ecuador. Am J Case Rep, 20(1): 1402-1406.

New research perspectives on the ecoepidemiology of neglected intestinal helminthiasis in urban-

marginal and rural areas of the province of Guayas (Ecuador)

Roldán W, Espinoza Y, Huapaya P, Jiménez S. (2010). Diagnosis of

human toxocarosis. Rev Peru Med Exp Salud Publica, 27(4): 613-

20.

Department of Appraisal and Cadastre of the Municipality of

Guayaquil. Population and number of families of the Urbano

Estacio Cooperative and the Brickyard of the City of Guayaquil.

2022.

Department of Appraisal and Cadastre of the Municipality of Nobol.

Population and number of families in the Loma Larga sector.

2022.

Department of Appraisal and Cadastre of the Municipality of Daule.

Population and number of families of Santa Rosa sector. 2022.

WinEpi (2022). Working in Epidemiology. Available at:

http://www.winepi.net/.

Cooper P, Guevara A, Guderian R (1993). Intestinal helminthiases in

Ecuador: the relationship between prevalence, genetic, and

socioeconomic factors. Rev Soc Bras Med Trop, 26(3): 175-80.

Moncayo A, Lovato R, Cooper P (2018). Soil-transmitted helminth

infections and nutritional status in Ecuador: findings from a

national survey and implications for control strategies. BMJ

Open, 8(1): 1-9.

Venables W, Smith D, Core Team R. (2022). An introduction to R.

Notes on R: A Programming Environment for Data Analysis and

Graphics. Version 4.2.0, p. 99. Available at: https://cran.r-

project.org/doc/manuals/r-release/R-intro.pdf.

RStudio Team (2022). RStudio: Integrated Development for R.

RStudio, PBC: Boston, MA. Available at:

http://www.rstudio.com/.

Willis H. (1921). A simple levitation method for the detection of

hookworm ova. Med J Aust, 2(18): 375-76.

Fabián E, Tello R, Náquira C. (2003). Manual of laboratory procedures

for the diagnosis of intestinal parasites in man. National Institute

of Health of Peru, 37(1): 18-22.

Center for Disease Control and Prevention (CDC). (2021). DPDx -

Laboratory Identification of Parasites of Public Health Concern.

Stool Specimens - Specimen Processing.

Avila HG, Risso MG, Cabrera M, Ruybal P, Repetto SA, Butti MJ, et

al. (2021). Development of a New LAMP Assay for the Detection

April - June vol. 2. Num. 2 - 2023

of Ancylostoma caninum DNA (Copro-LAMPAc) in Dog Fecal

Samples. Front. Vet. Sci. 8:770508. doi:

10.3389/fvets.2021.770508.

Weather Spark (2022). Weather all year round anywhere in the world.

Weather reports with weather by month, day and even hour.

Available at: https://es.weatherspark.com/

Weather Atlas (2022). Weather forecasts and weather forecast

information. Available at: https://www.weather-atlas.com/es.

Meteored (2022). 14-day weather forecast. Available at:

https://www.meteored.com.ec/.

Institute of Meteorology and Hydrology (INAMHI) (2023). Weather

forecast. Available at: http://www.inamhi.gob.ec/.

National Program for the Multidisciplinary Approach to Neglected

Parasitosis in Ecuador (PROPAD) (2013). Prometeo Ana Ruano

presented a plan to address parasitosis in Ecuador. Senescyt.

Available at: https://www.educacionsuperior.gob.ec/prometeo-

ana-ruano-presento-un-plan-para-abordar-la-parasitosis-en-el-

ecuador/

Pan American Health Organization. (PAHO). (2011). Integrated Action

Plans for the Prevention, Control and Elimination of Neglected

Infectious Diseases. p. 1-101. Available at:

file:///C:/Users/Univ.%20de%20Guayaquil/Downloads/Informe-

taller-EID-spa%20(1).pdf.