Viral diseases: Introduction. A viral infection is any type of illness or disease caused by a virus, a type of microbe. Microbes are tiny organisms that cannot be seen without a microscope and include bacteria, fungi, and some parasites, as well as viruses.iral diseases: Introduction. A viral infection is any type of illness or disease caused by a virus, a type of microbe. Microbes are tiny organisms that cannot be seen without a microscope and include bacteria, fungi, and some parasites, as well as viruses.
OPTAR stands for Operating/Operational Target. Operating Targets. Operations, Planning, Training and Resource Support Services. Oceanside Photo & Telescope Astronomical Society (San Diego County, CA) Operational Tasking. Operational Tasking Data Link. Operational Tasking Nuclear. Occasional Papers in Translation and Textlinguistics.
OPT stands for Optional Practical Training, this allows F1 students to work on a full time basis for one year after they have completed their studies, in a field related to their major. CPT stands for Curricular Practical Training and allows F1 Students to work for up to 20 hours a week in a field related to their major, while engaging in studies.