
==== Front
Iran J Parasitol
Iran J Parasitol
IJPA
Iranian Journal of Parasitology
1735-7020
2008-238X
Tehran University of Medical Sciences

10.18502/ijpa.v19i3.16399
IJPA-19-376
Letter to the Editor
Occurrence and Environmental Factors Associated with Cryptosporidium in South-Eastern Iran
Shahraki Reza 1
Rezaei Mahdi 2
Dabirzadeh Mansour 1 *
1. Department of Parasitology and Mycology, School of Medicine, Zabol University of Medical Sciences, Zabol, Iran
2. Department of Epidemiology & Biostatistics, School of Public Health Sciences, Isfahan University of Medical Sciences, Isfahan, Iran
* Corresponding author: Email: mdabirzadeh20002000@gmail.com
Jul-Sep 2024
19 3 376378
16 6 2024
05 7 2024
Copyright © 2024 Shahraki et al. Published by Tehran University of Medical Sciences.
2024
https://creativecommons.org/licenses/by-nc/4.0/ This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International license (https://creativecommons.org/licenses/by-nc/4.0/). Non-commercial uses of the work are permitted, provided the original work is properly cited.
==== Body
pmcDear Editor-in-Chief

Cryptosporidium is a protozoan parasite causing significant waterborne illnesses, posing a primary concern for water treatment and public health (1). The seroprevalence in these regions is 25–35%, especially in children (2). As of 2021, 44 species of Cryptosporidium have been validated, 20 of which can infect humans (3). C. hominis and C. parvum are responsible for most human infections. Environmental factors such as pH, water temperature, turbidity, dissolved oxygen, salinity, and organic matter influence Cryptosporidium survival and presence (4).

This study was conducted from April 2021 to August 2022, via collecting water samples from Zahedan and Zabol cities in southeastern Iran's Sistan and Baluchistan provinces. Random sampling was performed at 80 locations in Zabol City, including surface, tap, bottled, well, and wastewater sources (5).

This study was approved by the University Research and Ethics Committee (code: http://ethics.research.ac.ir/IR.ZBMU.REC.1398.159).

Health and safety protocols were implemented (6). A minimum of 10 liters of water was collected for environmental samples, following the EPA Method 1623.1 (7). The samples were filtered through a membrane with a 2–3 μm pore size using the Centrifugal Vacuum Filtration method. Pellets trapped in the filter were removed and centrifuged to concentrate the oocysts (8).

The modified Ziehl-Neelsen method using microscopy identified the oocysts by staining them with carbon fuchsin, destaining them with alcohol, and counterstaining them with methylene blue (9).

Of 180 water samples, 35 were positive for Cryptosporidium oocysts, 142 were negative, and three were suspicious. Cryptosporidium was most frequent at pH 7. Table 1 shows a significant difference between water temperature and the presence of Cryptosporidium oocysts, with more oocysts observed at temperatures between 20 and 30°C (P<0.001, TUKEY test) oocysts, with more oocysts observed at temperatures between 20 and 30°C (P<0.001, TUKEY test).

Table 1: Frequency and comparison of positive(A), suspected(B), and negative(C) Cryptosporidium parasite cases according to water PH, with a significant relationship between positive and negative samples

PH	Result	No.	Mean	Std. Deviation	95% Confidence Interval for Mean	p-value	Post-Hoc	
	
Lower Bound	Upper Bound	
A	Positive	35	7.3257	.19303	7.2594	7.3920	P<0.001	A>C	
B	suspicious	3	7.3667	.15275	6.9872	7.7461			
C	Negative	142	7.0963	.15489	7.0706	7.1220			
	Total	180	7.1454	.18795	7.1178	7.1731			
*. The mean difference is significant at the 0.05 level.

Regarding the relationship between Cryptosporidium spp., pH, temperature, and physical characteristics, a higher prevalence of Cryptosporidium parasites was observed in clear water (Fig. 1).

Fig. 1: Frequency of association between Cryptosporidium, physical characteristics (Clear, Translucent, Semi Cloudy, Cloudy water) of water that can affect the survival and presence of Cryptosporidium, water, temperature, and water pH in two Zahedan and Zabol Cities

This study examined the relationship between Cryptosporidium frequency and water clarity in each city. More parasites were found in the semi-cloudy water of Zabol and the cloudy water of Zahedan. Cryptosporidium was not detected in saline water.

Continuous surveillance and monitoring are crucial for identifying and responding to potential Cryptosporidium outbreaks in water, including routine testing of treated water (10).

Conflict of Interest

The authors declare that there is no conflict of interests.
==== Refs
References

1. Golomazou E Mamedova S Eslahi AV Karanis P. Cryptosporidium and agriculture: A review. Sci Total Environ. 2024:170057.38242460
2. Dabirzadeh M Khoshsima Shahraki M Rostami D Bagheri S. Prevalence of Cryptosporidium species in children referred to central and hospital laboratories of Zabol city, southeast of Iran. Int J Pediatr 2017;5 (12 ):6359–64.
3. Cruz-Saavedra L Arévalo VA Garcia-Corredor D Molecular detection and characterization of Giardia spp., Cryptosporidium spp., and Blastocystis in captive wild animals rescued from central Colombia. Int J Parasitol Parasites Wildl. 2023;22 :1–5.37576459
4. Bilal H Li X Iqbal MS Tulcan RXS Chhetri MT. Unveiling the Dynamics of Cryptosporidium in Urban Surface Water: A Quantitative Microbial Risk Assessment and Insights into Climatic and Seasonal Influences. Water. 2024;16 (10 ):1352.
5. Sargazi S Mokhtari M Ehrampoush MH Applying the geographical information system (GIS) approach to assess groundwater quality of Zahedan City, Sistan and Baluchestan Province, Iran. Ground Sustain Dev. 2021;12 :100509.
6. Brown CA Dunn JJ . Laboratory safety. Clin Lab Manage Rev. 2024:343–72.
7. Fradette MS Bourque SL Rodriguez MJ Charette SJ. Year-round monitoring of three water sources in Québec, Canada, reveals site-specific differences in conditions for Cryptosporidium and Giardia contamination. Can J Microbiol. 2024; 70 (7 ):262–274.38700083
8. Omar M Etewa SE Mahmoud SA Farag TI. Assessment of the potential occurrence of Cryptosporidium species in various water sources in Sharqia Governorate, Egypt. J Parasit Dis. 2024: 48 (2 ):358–369.38840871
9. Hazra D Krithika M Shenoy VP Chawla K. Evaluation of phenol ammonium sulfate basic fuchsin and auramine O staining by pot technique for the detection of acid-fast bacilli among patients suspected of pulmonary tuberculosis. Biomedicine. 2022;42 (4 ):757–60.
10. Chalmers RM Katzer F. Looking for Cryptosporidium: the application of advances in detection and diagnosis. Trends Parasitol. 2013;29 (5 ):237–51.23566713
