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Infectious diseases<span> are those that are </span>transmitted<span> from person to person by direct or indirect contact. Viruses, bacteria, parasites, and fungi all cause infectious </span>disease<span>. Malaria, measles, and respiratory illnesses are examples of infectious </span>diseases<span>.</span>
Answer:
Zebra mussels are spread from one body of water to another by natural flow, carried on the feathers or feet of birds, or by humans in bait buckets or on boats.
Dogs, cats, ferrets, seals, elephants, mustelids and bears own the "Zonary" placentae.