Answer: Outbreak of psoriasis
Step-by-step explanation:
The out break of psoriasis is caused due to the weak immune system which is enhanced during certain weather condition. Other conditions can also increase the susceptibility towards this disease such as certain medications, dry weather conditions et cetera.
Other reasons such as abandoned spray device, unusual sickness of people, unscheduled and unusual spray being disseminated. These activities are possible indicator of biological agent.