▁Virginia , ▁with ▁ 5 . 2 % ▁of ▁patients ▁treated ▁by ▁West ▁Virginia ▁health ▁care ▁prov iders ▁having ▁influen za - like ▁ill ness , ▁a ▁major ▁increase ▁from ▁ 2 % ▁of ▁patients ▁treated ▁by ▁West ▁Virginia ▁health ▁care ▁prov iders ▁having ▁influen za - like ▁ill ness ▁in ▁November . ▁ ▁Fl u ▁stra in ▁sever ity ▁ ▁The ▁new ▁stra in ▁was ▁identified ▁as ▁a ▁combination ▁of ▁several ▁different ▁stra ins ▁of ▁In fl uen z av irus ▁A , ▁sub type ▁H 1 N 1 , ▁including ▁separate ▁stra ins ▁of ▁this ▁sub type ▁circul ating ▁in ▁humans ▁( see ▁human ▁influen za ) ▁and ▁in ▁p igs ▁( see ▁sw ine ▁influen za ). ▁The ▁stra in ▁transm its ▁between ▁humans ▁and ▁was ▁initially ▁reported ▁to ▁have ▁a ▁relatively ▁high ▁mort ality ▁rate ▁in ▁Mexico . ▁The ▁World ▁Health ▁Organ ization ▁( W HO ) ▁and ▁the ▁U . S . ▁Cent ers ▁for ▁D ise ase ▁Control ▁and ▁Pre vention ▁( CD C ) ▁have ▁expressed ▁serious ▁concerns ▁that ▁the ▁new ▁stra in ▁has ▁the ▁potential ▁to ▁become ▁an ▁influen za ▁pan demic . ▁It ▁is ▁reported ▁that , ▁because ▁the ▁virus ▁is ▁already ▁w ides p read , ▁contain ment ▁will ▁be ▁impossible . ▁ ▁In ▁addition , ▁the ▁flu ▁death ▁to ll ▁in ▁Mexico ▁could ▁be ▁lower ▁than ▁first ▁thought , ▁Ger ald ▁Evans , ▁head ▁of ▁the ▁Association ▁of ▁Medical ▁Micro bi ology ▁and ▁In fect ious ▁D ise ase ▁Canada ▁and ▁a