Human Health and Disease

• Disease is characterised by various signs and symptoms.

• It spreads through infectious agents that include bacteria, viruses, protozoans and fungi.
  • Bacterial diseases
    • Typhoid fever: Salmonella typhi; Widal test is used for confirmation of typhoid
    • Pneumonia: Streptococcus pneumoniae and Haemophilus influenzae; it infects the alveoli of lungs
    • Other examples include dysentery, plague, diphtheria
  • Viral diseases
    •  Common cold: Spreads through Rhino viruses…