Theory:

Cleanliness:
Cleanliness is the maintenance of personal and environmental hygiene.
It is the state of being clean which is essential for good health. To protect ourselves from diseases, it is necessary to maintain good health by bathing regularly, cleaning the clothes and surroundings and avoiding unhygienic food consumption.
Faecal-Oral route of disease transmission:
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Faecal-oral route mode of transmission
 
It is a mode of transmission of diseases in which the disease-causing factor is transmitted to the living organisms through the contamination of food and water with animal excreta.
 
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Modes of transmission
Personal hygiene:
The branch of health is concerned with the adjustment to the physiological needs of an individual's body and mind so that the maximum level of health is attained known as personal hygiene.
The cleaning of ears and grooming of the body with a clean comb is also known as personal hygiene.
 
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Personal hygiene care
How do pathogens spread?
Depending on the pathogen, it can be spread in a variety of ways. Skin contact, body fluids, airborne spores, contact with faeces, and touching a surface touched by an infected individual are all ways they can spread.
Cold and flu are the common communicable diseases. Both bacteria and virus cause these diseases. When a person has a cold and flu, he also has running nose, cough, sore throat and sometimes fever or joint pains. In certain conditions, it leads to diarrhoea.
The secretions that ooze out from the nose may contain bacteria or virus. When the patient with this running nose touches the nose and then any other object or anyone else the virus is transferred. The condition becomes airborne when the patient sneezes or coughs. This is because the virus comes out as droplets.
 
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Dispersion of droplets
 
Hence it is a good practice for the patient with cold and flu to use a handkerchief to blow the nose. It is also mandatory that they wash the hands often not accidentally to spread the virus to others.
Reference:
https://www.vecteezy.com/vector-art/304386-simple-coloured-sketches-of-people-taking-a-bath
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