Questions of origins and questions of disease control are not the same thing once human-to-human transmission has become common, said Deborah Seligsohn, an expert in environment and public health at Villanova University. For example, scientists never confirmed the origin of smallpox before the disease was eradicated through a global vaccination program. In the case of Severe Acute Respiratory Syndrome (SARS)  a disease caused by a beta coronavirus, like the current coronavirus  researchers first identified the virus in February 2003. From a public health perspective, if a virus has transitioned to being spread mostly by human-to-human contact, discovering its origins is not as essential to strategies for containing the disease. WHAT DO SCIENTISTS BELIEVE ABOUT VIRUS ORIGINS?
visiting the sick is an annual event.
( z0 rate-entity :ARG1 ( z1 visit :ARG1 ( z2 person :ARG1-of ( z3 sick ) ) ) :ARG2 ( z4 temporal-quantity :quant 1 :unit ( z5 year ) ) )
(z0 / rate-entity-91
    :ARG1 (z1 / visit-01
              :ARG1 (z2 / person
                        :ARG1-of (z3 / sick-05)))
    :ARG2 (z4 / temporal-quantity
              :quant 1
              :unit (z5 / year)))
visiting the sick is an annual event .
z1 :ARG1 z2
z2 :ARG1-of z3
z0 :ARG1 z1
z0 :ARG2 z4
z4 :unit z5
z4 :quant 0