TY  - BOOK
AU  - Lapid,Nancy
TI  - Virus variants found to be deadlier, more contagious; some may thwart vaccines
KW  - Virus variants
KW  - thwart vaccines
KW  - deadlier
UR  - http://elibrary.doh.gov.ph/cgi-bin/koha/opac-retrieve-file.pl?id=dee253372509fe62add75e77483d0476
ER  -