Pathogens can become virulent and their spread is caused mainly by the ease of travel to countries where bacteria and virus based illnesses are well established and where poor quality water, low standards of hospital care, diminished living conditions, lack of proper waste handling and storage cultivate infectious zones. Danger of infection increases when proper procedures are not followed by those in high risk areas such as medical environments (Healthcare Acquired Infections) and food preparation areas.
How Pathogens Spread Disease
In Air – Droplets fly through the air when people sneeze or cough and people breathe them in. E.g. Chicken pox, flu, measles, and tuberculosis.
Contact with Animals – Animals carry harmful bacteria which can transfer to a person who is scratched or bitten. This is an issue particularly in tropical climates.
Contaminated Food – Carless handling of food can cause food poisoning and increase the risk of harmful bacteria spreading.
In Water – Water can carry harmful bacteria which gets into the body when swallowed.