The detection rate of rotaviruses from diarrheal stools in Lao People's Democratic Republic (Lao PDR) was studied in the period from 1994 to 2003. Rotavirus antigen was detected using latex agglutination kit. The average detection rate was 2.4%, or 18 of 738 cases examined in total. Rotavirus was not detected from 175 cases examined in 1995, 1998, 2000 and 2003, but 8 of 85 cases (9.4%) examined in 1997 were positive for rotavirus. The detection rate was 6.0% in the age group younger than 2 years and 0.6% in the age group older than 2 years. These detection rates were markedly lower than those in neighboring countries such as Vietnam and Thailand.

In order to determine the epidemiological features of cholera in Lao PDR, the presence of mobile genetic elements such as plasmid, class I integron and SXT element in V. cholerae isolated from surface water were examined. Among the 22 strains isolated from 13 distantly separated sampling sites, no mobile genetic elements associated with drug resistance were found reflecting the antibiogram of the strains. Nevertheless, cholera epidemics due to multiple drug resistant V. cholerae occurred repeatedly in those areas until 2000.