Which one of the following diseases is communicable and not caused by a bacteria?

The correct option is B Swine flu
Communicable diseases are those disease which can transmitted through an external agent ( bacteria, virus, protozoa etc.) or from an infected person to a healthy but susceptible persons. The disease spreads either through a vector or through agencies like food, water etc. typhoid and typhus are communicable bacterial diseases, where typhoid is transmitted from contaminated food and typhus spreads through human lice (external agent). Diabetes is a non-communicable disease cause due to disruption of body function and swine flu is caused by a specific influenza virus spreads due to unhygienic conditions