Findings and lessons from establishing Zika virus surveillance in southern Viet Nam, 2016

Objective@#To document the evolution and optimization of the Zika virus (ZIKV) disease surveillance system in southern Viet Nam in 2016 and to describe the characteristics of the identified ZIKV-positive cases.@*Methods@#We established a sentinel surveillance system to monitor ZIKV transmission in eight sites in eight provinces and expanded the system to 71 sites in 20 provinces in southern Viet Nam in 2016. Blood and urine samples from patients who met the case definition at the sentinel sites were tested for ZIKV using real-time reverse transcription polymerase chain reaction at the Pasteur Institute in Ho Chi Minh City (PI-HCMC). We conducted descriptive analysis and mapped the ZIKV-positive cases.@*Results@#In 2016, 2190 specimens from 20 provinces in southern Viet Nam were tested for ZIKV at PI-HCMC; 626 (28.6%), 484 (22.1%), 35 (1.6%) and 1045 (47.7%) tests were conducted in the first, second, third and fourth quarters of the year, respectively. Of these tested specimens, 214 (9.8%) were ZIKV positive with 212 (99.1%) identified in the fourth quarter. In the fourth quarter, the highest positivity rate was those in age groups 30–39 years (30.0%) and 40–59 years (31.6%). Of the 214 ZIKV-positive patients, 210 (98.1%) presented with rash, 194 (90.7%) with fever, 149 (69.6%) with muscle pain, 123 (57.5%) with joint pain and 66 (30.8%) with conjunctivitis.@*Discussion@#The surveillance system for ZIKV disease underwent several phases of optimization in 2016, guided by the most up-to-date local data. Here we demonstrate an adaptable surveillance system that detected ZIKV-positive cases in southern Viet Nam.

Detection and clearance treatment of typhoid fever patient in Cai Lay district (Tien Giang), 1998-1999

During 1998-1999, among 403 typhoid fever patients at CaiLay district hospital, 359 cases were taken blood culture. The positive blood culture rate was 14,8%. 44 positive cases were followed up for stool culture after the treatment. The positive stool culture rate was 10% in 1998 and 0% in 1999. Suspected typhoid fever cases and positive blood culture cases were mainly from 5 to 19 years-old with the peak at age group from 5 to 9 years-old. Typhoid fever rate was high from the end of dry season and during the rainy season. Among positive blood culture cases, S.typhi was isolated in 50/53 cases and S. paratyphi in 3/53 cases. Resistance rates to ampicilline and Bactrim were over 90%, to chloramphenicole and amoxicilline over 80%. Sensitive rates to ciprofoxacin were 90%.