Objective: Determine the Polio virus serotypes from acute flaccid paralysis patients in the Northern Vietnam 2005-2007. Subject: Strains (132 strains) intestinal virus isolated from 690 patients with acute flaccid paralysis supervised detected in 3 years, from 2005 to 2007 in the North were included in the study of the structure and some of the root distribution characteristics intestinal virus strains isolated from patients. Method: The study virology laboratory. Results: The research results have identified 132 positive samples, accounting for 19.1 percent of the total samples were collected during 3 years from the acute flaccid paralysis patients from all causes. There are 5 types isolated intestinal virus including Echo virus (53 percent of the total number of positive samples), CA (15.9 percent), CB (17.4 percent), EV71 (6.1 percent). Especially among the group isolated from clinical specimens 10 samples of Polio virus, representing 7.6 percent of the total number of positive samples, all of the Sabin Polio virus. Polio has 10 strains are identified by means of neutralizing serotype trace with specific antiserum. Result 4 Polio virus strains are type 1 (40 percent of the total number of samples positive for Polio virus)
3 strains of polio virus type 2 (30 percent) and 3 strains of polio virus type 3 (30 percent). Ten strains were also identified by antigenic molecular biological methods RT-PCR / RFLP and monoclonal antibody methods. analytical results as well as antigen-specific genetic material of all 10 strains of polio virus isolated in the years 2005-2007 by the neutralization method and the method of trace RT-PCR/RFLP has affirmed all these strains are Sabin strains (strains produce oral polio vaccine) due to the image of identical DNA fragments together serotype standard Sabin strains.