The human body can provide places for disease-causing germs and parasites to grow and multiply. These places include the skin and in and around the openings to the body. It is less likely that germs and parasites will get inside the body if people have good personal hygiene habits.

7.1 Good personal hygiene

Good personal hygiene habits include:
  • washing the body often. If possible, everybody should have a shower or a bath every day. However, there may be times when this is not possible, for example, when people are out camping or there is a shortage of water
  • If this happens, a swim or a wash all over the body with a wet sponge or cloth will do
  • cleaning the teeth at least once a day. Brushing the teeth after each meal is the best way of making sure that gum disease and tooth decay are avoided. It is very important to clean teeth after breakfast and immediately before going to bed
  • washing the hair with soap or shampoo at least once a week
  • washing hands with soap after going to the toilet
  • washing hands with soap before preparing and/or eating food. During normal daily activities, such as working and playing, disease causing germs may get onto the hands and under the nails. If the germs are not washed off before preparing food or eating, they may get onto the food
  • changing into clean clothes. Dirty clothes should be washed with laundry soap before wearing them again
  • hanging clothes in the sun to dry. The sun's rays will kill some disease-causing germs and parasites
  • turning away from other people and covering the nose and mouth with a tissue or the hand when coughing or sneezing. If this is not done, droplets of liquid containing germs from the nose and mouth will be spread in the air and other people can breathe them in, or the droplets can get onto food
Fig.  3.17: Washing the body helps keep it free of disease-causing germs
Fig. 3.17: Washing the body helps keep it free of disease-causing germs
Fig.  3.18: Cleaning teeth helps keep gums and teeth healthy.
Fig. 3.18: Cleaning teeth helps keep gums and teeth healthy.
Fig.  3.19: Washing hands after going to the toilet helps stop the spread of germs.
Fig. 3.19: Washing hands after going to the toilet helps stop the spread of germs.
 Fig.  3.20: Washing hands before preparing food helps keep germs out of our bodies.

Fig. 3.20: Washing hands before preparing food helps keep germs out of our bodies.
Fig.  3.21: Washing hands before eating food helps stop germs getting into our bodies
Fig. 3.21: Washing hands before eating food helps stop germs getting into our bodies
Fig.  3.22: Washing clothes helps keep them free of disease-causing germs.
Fig. 3.22: Washing clothes helps keep them free of disease-causing germs.
Fig.  3.23: Hanging clothes in the sun helps to kill some disease-causing germs and parasites.
Fig. 3.23: Hanging clothes in the sun helps to kill some disease-causing germs and parasites.
Fig.  3.24: Covering the nose and mouth when sneezing helps stop the spread of germs.
Fig. 3.24: Covering the nose and mouth when sneezing helps stop the spread of germs.

7.2 Overcrowding

When there are too many people in any house, the likelihood of them getting disease is greater than if the house is not overcrowded. This is because people in an overcrowded house will be much closer to each other and it is therefore easier for any germs to spread from one to another. For example:
  • sneezing and coughing in crowded rooms makes it easier to spread cold and flu germs
  • sharing towels can spread trachoma germs and other germs which cause eye infections (runny or sore eyes)
  • several children sleeping in the same bed makes it easier to spread a scabies infection
Fig.  3.25: Overcrowding helps spread germs and parasites such as scabies
Fig. 3.25: Overcrowding helps spread germs and parasites such as scabies.

Each house is designed to allow a particular number of people to live there comfortably. This number will depend upon the number and size of the rooms, especially bedrooms, and the size of other facilities such as the sewage system and washing and cooking areas.

If the number of people living in the house is greater than the number it was designed for, these facilities will not be able to cope properly. For example, large numbers of people using the toilet may mean that the septic tank will not be big enough to take and treat the additional load of sewage.

For good health and comfort, the number of people who should live in a house depends upon the factors outlined below.

The number and size of bedrooms

While most people who live permanently in a house will have a bedroom to themselves or share one with one or two other people, other rooms are often used as bedrooms. The number of people who should sleep in a room will depend upon the amount of air which is available to each person. The law requires that each adult person has at least 13 cubic metres of air and each child has at least 10 cubic metres of air in a sleeping area.

The type and size of the sewage system

Usually, a household septic tank system with 2 round tanks caters for a maximum of ten people.

The size and availability of other facilities

The facilities within the house may not be able to handle all of the demands placed on them by the occupants. For example, the hot water system may not be able to produce enough hot water, or the amount of food to be chilled is too great for the refrigerator to hold.

In Indigenous communities, overcrowding in houses occurs for a number of reasons, such as:
  • there not being enough houses for the number of people who live in the community
  • families not being able to afford to pay rent on a house of their own and needing to live with relatives to share the cost
  • people visiting relatives and staying for a long time
  • visitors coming to stay so that they can attend special events such as funerals
It is important that EHPs remember that overcrowding is a significant environmental health problem in many communities.