outbreak at Rotterdam Zoo
... that until the outbreak at Rotterdam Zoo in 1964, monkeypox was thought to occur only in primates?
... that until the <b id="mwBAk"><a href="./Outbreak_of_monkeypox_at_Rotterdam_Zoo" id="mwBAo" rel="mw:WikiLink" title="Outbreak of monkeypox at Rotterdam Zoo">outbreak at Rotterdam Zoo</a></b> in 1964, <a class="mw-redirect" href="./Monkeypox" id="mwBAs" rel="mw:WikiLink" title="Monkeypox">monkeypox</a> was thought to occur only in primates?