Triple antigen is a combined vaccine for protection against Diphtheria, Pertussis (whooping cough) and Tetanus.

i) The vector of malarial parasite is female Anopheles mosquito.
ii) Malaria is caused by Plasmodium falciparum is malignant and fatal.

1. Prevention of mosquito bites by using mosquito nets, mosquito screens, mosquito repellents and ointments.
2. Elimination of breeding places by providing adequate sanitation, underground waste water disposable system and drainage of stagnant water. 
3. Collection of water in any uncovered container such as water tank, pots, flower pots discarded tyres should be avoided.
4. Control of mosquito larvae by spraying oil on stagnated water bodies.
5. Adult mosquitoes can be killed by spraying insecticides.
6. Application of citronella oil or Eucalyptus oil on the exposed skin.

Endemic:
When the disease is found in certain geographical area affecting a fewer number of people. Eg. Occurance of goitre in Sub Himalayan regions.
Epidemic:
When the disease breaks out and affects large number of people in a particular geographical region and spreads at the same time. Eg. Influenza
Pandemic:
When the disease is widely distributed on a global scale.
Eg. Acquired Immuno Deficiency Syndrome
Sporadic:
When there is an occasional occurance of disease.
Eg. Malaria and cholera.

Viruses are categorized as
i) Plant virus:
Virus that infect plants,
eg: Tobacco mosaic virus, cauliflower mosaic virus, Potato virus.

ii) Animal virus:
Virus that infect animals
eg: Adenovirus, Retrovirus(HIV), Influenza virus

iii) Bacteriophages:
Virus that infect bacterial cells.
eg: T4 Bacteriophage

Based on the shapes, bacteria are grouped as

1. Spherical shaped bacteria called as cocci or coccus for a single cell.
2. Rod shaped bacteria called as bacilli or bacillus for a single cell.
3. Spiral shaped bacteria called as spirilla or spirillum for single cell.