▁be ▁indirect ly ▁spread ▁by ▁f om ites . ▁Distribution ▁is ▁world wide ▁and ▁the ▁virus ▁inf ect s ▁a ▁range ▁of ▁r umin ants , ▁including ▁b ison , ▁buff alo , ▁sheep ▁and ▁go ats . ▁ ▁The ▁disease ▁may ▁be ▁referred ▁to ▁as ▁a ▁passenger ▁virus . ▁ ▁C lin ical ▁Sign s ▁& ▁Di agn osis ▁ ▁B H V - 4 ▁in fection ▁is ▁often ▁sub cl in ical , ▁with ▁no ▁observable ▁clin ical ▁signs . ▁However ▁the ▁virus ▁may ▁cause ▁abort ion ▁and ▁retained ▁fo etal ▁memb ran es , ▁and ▁if ▁an ▁inf ected ▁fet us ▁is ▁born ▁alive ▁it ▁may ▁be ▁weak . ▁It ▁can ▁also ▁cause ▁m ast itis ▁in ▁da iry ▁cattle . ▁It ▁may ▁be ▁isolated ▁from ▁conj unct iv itis ▁and ▁resp ir atory ▁disease ▁cases ▁but ▁it ▁is ▁unknown ▁whether ▁the ▁E H V - 4 ▁is ▁a ▁primary ▁or ▁opportun istic ▁path ogen ▁in ▁these ▁cases . ▁ ▁Di agn osis ▁is ▁achieved ▁by ▁virus ▁isol ation ▁( from ▁t issues ▁or ▁secret ions ), ▁PC R , ▁EL IS A , ▁and ▁indirect ▁imm un of lu ores c ence . ▁Because ▁B H V - 4 ▁in fection ▁can ▁be ▁asympt om atic , ▁the ▁presence ▁of ▁the ▁virus ▁does ▁not ▁confirm ▁that ▁it ▁was ▁the ▁cause ▁of ▁the ▁observed ▁clin ical ▁signs . ▁ ▁Tre at ment ▁& ▁Control ▁ ▁Tre at ment ▁is ▁sympt om atic . ▁The ▁virus ▁can ▁remain ▁lat ent ▁in