# Malaria thick blood film

Microscopy analysis of Giemsa-stained thick and thin blood films from peripheral blood is intended to detect, identify, and quantify malaria parasites.

**Thick films** allow the microscopist to screen a larger volume of blood and are about eleven times more sensitive than the thin film, so picking up low levels of infection is easier on the thick film, but the appearance of the parasite is much more distorted and therefore distinguishing between the different species can be much more difficult.

![ Template for preparation of slides with thick and thin blood films](https://357738419-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-MJNQBgYLwFTXBIbt1TJ%2F-MJhQJE8WuGs4uTSbRmB%2F-MJhUL7qj8n5yA36iNFz%2Fimage.png?alt=media\&token=1e7fbdb6-0257-4616-b620-235b8ce5fd78)

![ Examining a thick blood film](https://357738419-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-MJNQBgYLwFTXBIbt1TJ%2F-MJhWkQNeKIJA0UAMzFk%2F-MJh_S8GsYDAXzqWERu8%2Fimage.png?alt=media\&token=ba5df3d4-291e-4063-b6cc-d67953d05eb3)

![Parasites in the thick film](https://357738419-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-MJNQBgYLwFTXBIbt1TJ%2F-MJhWkQNeKIJA0UAMzFk%2F-MJheWXFuJF5MPI1RKHF%2Fimage.png?alt=media\&token=11f46468-5186-44d0-9347-463535d3ad4a)

{% hint style="warning" %}
The procedure requires 100× oil-immersion objective lens
{% endhint %}

## Malaria thick, using Celly

#### Preparation 

Put the sample, turn on the light, use 100x objective lens magnification, and set the lens focus. Move the field of view to the single layer of cells.

#### Test execution

Tap the test configuration button: set "**Malaria Thick: parasites counting**" test type, choose a patient. 

Tap the app settings button. Set the WBC number to analyze (200 by default). Start the test.

Move your slide, controlling the focus. The App will count parasites and white blood cells. After reaching the specified number of cells, the application will complete the test.

#### Result review and confirmation

* Log in on the [**website**](https://app.celly.ai). Go to the [**Tests**](https://app.celly.ai/app/analysis/) page. Push the **View** button to open your report.
* Go to the **Cells** tab to check the pre-classification. Drag the cells to the appropriate type to correct errors. 
* The app automatically calculates
  * Fields of view analyzed
  * WBC number
  * Parasites number
  * Parasitemia (Parasites in 1μl) = Parasites \* 8000/WBC  

{% hint style="info" %}
Parasitemia is calculated for 8,000 WBC/μl level
{% endhint %}

![Thick film analysis interface](https://357738419-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-MJNQBgYLwFTXBIbt1TJ%2F-MR6V43_NuGD-xzAMkNq%2F-MR6VvcSlqhhH_vkMGxY%2Fimage.png?alt=media\&token=a6596df1-5610-4631-a572-677a687eb686)

**Links:**

* [Microscopy examination of thick and thin blood films for identification of malaria parasites, WHO, 2016](https://www.who.int/publications/i/item/HTM-GMP-MM-SOP-08)
* [Microscopy for the detection, identification and quantification of malaria parasites on stained thick and thin blood films in research settings. WHO on behalf of the Special Programme for Research and Training in Tropical Diseases, 2015](https://apps.who.int/iris/bitstream/handle/10665/163782/9789241549219_eng.pdf?sequence=1\&isAllowed=y)