Measles in Saudi Arabia: from control to elimination

This article describes the tremendous efforts made in the field of measles immunization in Saudi Arabia in the past 20 years, from the control phase to the elimination phase. Mandatory measles vaccination with one-dose Schwartz vaccine was introduced in 1982 by a royal decree, a step aimed at increasing vaccine coverage. In 1991, a two-dose schedule was implemented using Edmonston-Zagreb measles vaccine, with a first dose at 6 months to protect children younger than 9 months and a second dose of MMR at 12 months of age to protect those who did not respond to the first dose. A marked reduction in the epidemic peak and a shift of infection to older age were noticed. But the same data showed that 50% of measles cases in the 1- to 4-year age group occurred in vaccinated children. In 1998, with the start of elimination phase, an MMR campaign was launched in two phases, targeting school children in 1998 [secondary schools] and in 2000 [primary and intermediate schools]. Evaluation of the MMR campaign and surveillance data was reflected in the measles immunization policy by shifting the age of measles immunization to 12 months and to preschool using the two-dose MMR schedule

Screening of pregnant Saudi women for hepatitis B surface antigen

The high prevalence of hepatitis B surface antigen [HBsAg] and hepatitis B e antigen [HBeAg] in pregnant women is considered the most important factor contributing to the higher carrier rate of HBsAg in some populations, including Saudi Arabia. Universal hepatitis B vaccination in infancy was implemented in Saudi Arabia in 1990 to avoid early acquisition of infection. At the same time, another program was launched to vaccinate all school children at school entry as a second target group. The aim of this study was to evaluate the HBsAg prevalence rate in Saudi pregnant women 12 years after launching the program and to assess regional variation, if any. In a cross-sectional study, 2664 pregnant Saudi women were recruited from the five main regions in Saudi Arabia. Blood samples were tested for HBsAg. Positive samples were tested also for HBeAg. Of 2664 pregnant Saudi women, 65 were positive for HBsAg [2.46%, 95% CI=2.11%- 2.69%]. Four were positive for HBeAg [0.15%]. The HBsAg prevalence rate was higher in Gizan [4.2%] and lower in Tabuk [1.4%] [P=0.035]. Only one case was positive for HBsAg in women under the age of 20 years [1/186], a 0.5% positivity rate in this age group compared with 2.6% in the older age group [P=0.049 for the one-sided test]. A history of surgical procedures was associated with a higher [3%], but not significantly higher rate of HBsAg positivity. No significant association was found between HBsAg positivity and a history of dental procedures or blood transfusion.Although the HBsAg prevalence rate among Saudi pregnant women was lower than previously published data, the full impact of the hepatitis B vaccination program in infancy and childhood will take more years to decrease the prevalence rate in pregnant women. The MOH should continue to give the first dose of hepatitis B vaccine at birth to prevent early acquisition, but in the meantime a regional policy can be adopted to deal with the high prevalence rate of HBsAg among pregnant Saudi women