Giardia and Cryptosporidium Analysis

Cryptosporidium and Giardia are two pathogenic unicellular protozoa that seriously endanger water quality, and their oocysts or spores are characterized by their small size, low pathogenic dose, strong resistance to environmental selective pressure, and easy to cause outbreaks of both diseases, which have a global distribution. Giardia is mainly parasitic in the human small intestine and causes Giardiasis with diarrhea as the main symptom. Cryptosporidium parasitizes the brush border of the epithelial cells of the gastrointestinal tract in humans and other hosts, and is an important opportunistic pathogen that causes diarrhea in humans and animals.

Why Choose Giardia and Cryptosporidium Testing

First, to facilitate coordinated water treatment programs, the more Giardia and Cryptosporidium in the water, the more treatment is needed to reduce its levels in the water.

Second, to protect the public, as Giardia and Cryptosporidium can affect the health of those who drink it, and the cost of treating an infection is much higher than the cost of preventing it in advance;

In addition, in the event of a large-scale infection, the water company will be held legally responsible.

Testing Steps

Giardia and Cryptosporidium detection and analysis steps include capsule filtration, elution, centrifugation, immunoseparation, immunofluorescence staining and fluorescence microscopy.

1. Sampling and filtration process

BOC Sciences used a capsule filter to collect multiple water samples. It is easy to operate and saves operation time during filtration and elution, and is extremely simple to use without the need for other complicated devices, disassembly, installation and cleaning. The use of 1 µm absolute pore size ensures 100% retention of both worms and 100% detection of oocyst sporocyst integrity. Meanwhile, the elution rate reaches more than 80%.

2. Elution and centrifugal concentration process

The eluted material is eluted from the filter capsule with elution buffer solution, and the eluted material is centrifuged to make the oocysts and sporocysts settle at the bottom of the centrifuge tube, and the supernatant is removed from the tube to collect the liquid containing oocysts and sporocysts.

3. Immunomagnetic separation process

Buffer was added to each side flat-walled tube, then the liquid collected after centrifugation was added, followed by Cryptosporidium oocyst isolation beads and Giardia spore isolation beads. The tubes were placed on the sample mixer and rotated. After mixing well, the side flat-walled cuvettes were removed and placed on the magnetic pole for oscillation. HCl was added to the microcentrifuge tube and the mixture was vortexed to dissociate the oocysts and sporocysts from the magnetic beads. The purified solution containing oocysts and sporocysts is transferred to a well-shaped slide.

4. Staining and filming process

Oocysts and sporocysts are colored by fluorescent staining solution and DAPI solution on the well-shaped slides. After the smear was dried, a drop of DAPI staining solution was added to the smear and washed with distilled water. A drop of fluorescent staining solution was added to the smear and washed with fixed buffer solution. Finally, add a drop of blocking gel and cover the coverslip, then you can observe under the microscope.

5. Microscopic examination process

Observe each slide, and perform qualitative and quantitative analysis on objects that match the size, shape and fluorescence characteristics of Cryptosporidium and Giardia.

Prevention and control of Giardia and Cryptosporidium

From the perspective of drinking water safety, we should pay attention to the danger of the two worms to human health, and strengthen the whole process of control and removal of inactivation from the source to the water point to minimize the danger of Cryptosporidium and Giardia. Drinking water treatment in the use of ultraviolet light method can be more effective in the inactivation of the two insects. In the chemical method, ozone oxidation method for the inactivation of the two insects is the best. The use of a variety of disinfectants used in combination, through synergy, can achieve a high inactivation rate.