• Earlier, people believe that diseases were caused by evil spirits, black magic or by the wrath of god. Hence, some typical methods were used to cure the diseases. But, later researchers have proved through their research that many diseases are caused by micro-organisms. This has proved that the old beliefs were absolutely false.
• There are two types of diseases – communicable diseases and non-communicable diseases. The diseases that are not transmitted from one individual to other individual are called as non-communicable diseases. Cancer, diabetes, aids, etc are some of the non-communicable diseases. The diseases that are transmitted from one individual and other individual are called as communicable diseases. Tuberculosis, cholera, jaundice, etc are some of the communicable diseases. They are also called as infectious diseases.
• We sometimes hear news of the epidemic of diseases such as tuberculosis, typhoid, cholera, diarrhoea or gastritis, jaundice or conjunctivitis. We have may seen someone in families of our acquaintance falling ill with the diseases like malaria, polio or diphtheria. We take certain measures to prevent diseases. These measures are called as preventive measures. The best way to prevent diseases is to prevent the germs of diseases from entering our body.
How do communicable diseases spread through micro-organisms?
• "Micro" means small and "organisms" means living things. We cannot see micro-organisms with our naked eye. But they can be seen with the help of a micro-scope. Micro-organisms are present everywhere – in the air, in water, in the soil, in the bodies of animals, etc. There are two types of micro-organisms – beneficial micro-organisms and nuisance micro-organisms. Beneficial micro-organisms do not create harm or provide mischief to us. For example, conversion of milk into curd requires some micro-organisms which help in the conversion process. Micro-organisms like bacteria, virus, fungi, etc cause disease. These are nuisance micro-organisms. They are called pathogens or disease producing micro-organisms. However micro-organisms are not pathogenic. That is, all do not cause diseases.
• When many people in a same place get the same disease at the same time, we say that there is an epidemic of the disease. Malaria, typhoid, jaundice, cholera, etc are some of the diseases that cause epidemics. People spend a lot of time with those who are suffering from tuberculosis or diphtheria is likely to get the disease. Diseases spread through micro-organisms with the help of air, water, food or some insects. When the germs of a disease enter our body and multiply itself, we can fall ill with the disease.
Spread of diseases through water
Diseases that are spread through water are called as water-borne diseases. Hepatitis A, typhoid, dysentery, cholera, diarrhoea are some of the water-borne diseases. The faeces of people having any of the diseases contain the pathogens. If their faeces enter water, then the germs in them also mix with the water, and the water is contaminated. When people consume the contaminated water, the pathogens in the water enter in their body and they are likely to contract the disease. Germs of jaundice spread in this way through contaminated water.
Prevention of diseases that spread through water
• The best way of preventing the spread of diseases through water is destroying all the pathogens present in drinking water.
• We can remove germs and waste particles from water at home by following some simple household tips. Take a piece of alum (a transparent solid substance) and place it in water for 1-2 hours and then waste particles shall settle near base of water. Slowly take out upper level water from the container. The process removes only waste particles but not germs. If we boil water for 15-18 minutes all the germs in it are destroyed and it becomes safe for drinking. This is the best method for killing germs from water.
• Big towns and cities have water purification plants. In these plants, water is treated using a number of different processes. As a result, the germs in the water are all destroyed. This safe of potable water is supplied to the people through closed pipes. In smaller places, germs in the water are destroyed by treating the water with bleaching powder.
• Do not let sewage water enter any public source of water.
• Do not bathe in a public source of water. Also, do not wash utensils, clothes or cattle, etc in that source.
• Do not defecate near a public source of water.
Spread of diseases through food
• Some diseases spread through foods. Flies sit on garbage and dirt. When flies sit on the faeces of people suffering from diseases, the germs in the faeces stick to the legs and body of the flies. When these flies sit on uncovered food, the germs enter the food and contaminate it. Consuming contaminated food lead to contracting diseases.
• There are many germs in the soil. They are blown into the air along with dust particles due to wind. When this dust sits on food, the food is contaminated. We often hear of people getting diarrhoea by consuming uncovered food from local food vendors. Those who cook, serve or sell this food have to handle the food. If some of them have intestinal diseases, and if they don't wash their hands clean after going to the toilet, the germs of the disease are likely to be present on their hands and under their nails. When these people touch the food while cooking and serving, the germs are likely to enter the food and spread from one person to another.
Prevention of diseases that spread through food
The law makes it obligatory to cover the food property when it is being sold in markets. When you buy food from the market and local food vendor, make sure that it was covered properly. Avoid eating or buying food kept in unclean surroundings. Due to the busy schedule of some people, sometimes they wish to prefer ready-to-eat food like "Maggi" which is available in market. But before purchasing the food from market, special care should be taken about expiry date of the food. One should completely utilize the food before end of its expiry date.
Spread of disease through air
Diseases that are spread through air are known as air-borne diseases. Chickenpox, smallpox, measles, influenza, tuberculosis, are diseases some of the air-borne diseases. Germs of tuberculosis are present in the spittle of person tuberculosis. When this person spits or coughs, the germs spread in the air. These germs enter the bodies of people who are nearby, through the air they breathe in. We have might have heard that someone contracted tuberculosis after spending a lot of time around a Tuberculosis patient. Hence tuberculosis patients are always advised not to spit anywhere they feel like. Other diseases of the lungs also spread through air. Diphtheria is a disease of throat. The germs of throat diseases spread through air.
Prevention of diseases that spread through air
• People suffering from communicable diseases like cold, cough, tuberculosis, diphtheria, chickenpox, etc should not mix with crowds. People who work near such patients should cover their nose and mouth with a clean cloth or a mask.
• People who have contracted diphtheria, measles, chickenpox, etc are kept in a special place/room, away from healthy people. The clothes and utensils used by those patients are thoroughly washed.
• There are large numbers of tuberculosis germs found in the spittle of Tuberculosis patients. To prevent the spread of Tuberculosis, the patient's spittle is collected in a spittoon and is sprayed with a germicide. This destroys the germs in the spittle.
Spread of disease by insects
Diseases that spread through direct contact are called contagious diseases. Using the clothes or other belongings of people having contagious diseases can cause the disease. Insects like mosquitoes, bedbugs, fleas etc spread diseases like malaria, dengue, etc. Very few from us know that we can get malaria if the female of anopheles mosquito bites us. A micro-organism called "Plasmodium" spreads malaria. The micro-organism use mosquitoes as a carrier for spreading of the disease. When a mosquito bites, i.e. sucks the blood of a malaria patient, the Plasmodium in that person's blood enters the mosquito's body. When this mosquito bites another person, the pathogens enter that person's body and cause the disease.
Prevention of diseases that spread through insects
• People should not use the clothes and other belongings of those who have contagious diseases like measles, ringworm, etc. People suffering from these diseases should careful to the cleanliness of their body. They should use soap to well clean their body and wipe themselves dry. Their clothes should be dried in the sun before they wear them again. This helps to kill the germs. Apart from these measures, it is necessary to consult a doctor and get proper treatment.
• There should not be any open gutters of water near the places where people live. Flies and mosquitoes breed on open garbage dumps and swampy places. Spread a thin film of petrol or kerosene on the water to destroy the larvae and eggs of mosquitoes and flies. This reduces the danger of the spread of diseases. Do not allow water to accumulate anywhere, during the rainy season or any other time. This helps to prevent the breeding of larvae of mosquitoes and fleas. Water stored in home for drinking or any other purpose must always be kept covered.
• When people go on a pilgrimage in large numbers, they are likely to contract cholera. To prevent this, they are given an injection of the cholera vaccine before they left. This protects them against cholera, even if the pathogens enter their body. A vaccine is also given as protection against hepatitis B which is another type of jaundice.
• Pay careful attention to information about the prevention of diseases given on newspaper, radio and television as well as on the posters at railway stations, bus stands or any other public places. This information is provided by Public Health Department. Following the instructions reduces the danger of contracting diseases. The information includes precautions about drinking water and the food we purchase from the market as well as local food vendor.
Vaccination is a best method, which protect us from selected pathogens. Vaccination helps the baby's body to combat against pathogens. Vaccines of diseases like polio, Tuberculosis, diphtheria and whooping cough are given to a new born baby as per the fixed time table, to give the baby protection against these diseases. As a result, even if the pathogens of these diseases enter the baby's body some time later. Pathogens shall not propagate in their body.
One more (good) reason to really wash your hands. I've also heard the anecdotal rumor that touchscreen devices are horrible for eyesight. One might reasonably expect that this is because fonts and displays are so small. Rather, the claim is that looking through a screen smeared by dirt and oil causes the eyes and the brain to struggle unnecessarily. It's like wearing dirty glass (although optically, not as bad).