Many towns of our country do not have sewer systems or sewage treatment plants. Bulk of this untreated sewage even in big cities flows into rivers, lakes or the sea causing water contamination.
Water treatment in urban areas becomes ineffective because of high pollution levels of surface water particularly in rainy seasons, or when water sources become relatively dry in summers. Contamination of water also occurs by sewage wherever the water and sewage pipes run in close proximity with each other.
At many places the water contains harmful minerals in it making it unfit for drinking. Such water if consumed may cause health problems.
2. Nutritional Deficiency Diseases:
Malnutrition is still common in our country. Many diseases such as Protein Energy Malnutrition (PEM) (for e.g. marasmus and kwashiorkor), mineral deficiency diseases (for e.g. goitre, anaemia) and diseases due to deficiency of vitamins (for e.g. xerophthalmia, rickets) etc. are common deficiency diseases.
3. Insect and Airborne Diseases:
Dengue, filariasis, malaria are some common diseases, germs of which are carried by insects (vectors). The breeding of houseflies, mosquitoes and other insects cause diseases, which is a major problem.
4. Diseases Due to Pollution:
The diseases caused due to air, water and soil pollution such as tuberculosis, asthma, etc. is a major problem of both indoor as well as outdoor pollution. Common indoor pollutants are tobacco smoke, particulate matter, nitrogen dioxide, carbon monoxide, volatile organic compounds and biological allergens, coal burning for cooking and heating. Indoor air pollution may increase the risk of irritation, allergy, acute and chronic respiratory disorders and lung diseases.
5. Problem of HIV/AIDS:
India has a large population and HIV/AIDS is one of the most challenging public health problem. The number of persons suffering from HIV/AIDS has increased sharply from a few thousand in the early 1990s to around 5.1 million in 2003.
6. Occupational Hazards:
There are many diseases related to one’s profession. For example, persons working in asbestos factories are prone to asbestosis. Similarly, persons working in carpet industry, jute mills, glass manufacturing units, firework industry, etc. are prone to hazards related to their profession.
7. Inadequate Medical Facilities:
At many places, adequate medical facilities are not available to cater to such a vast population.