Active Surveillance for Congenital Rubella Syndrome in Yangon, Myanmar/Surveillance Active Du Syndrome De Rubeole Congenitale a Yangon (Myanmar)/Vigilancia Activa del Sindrome De Rubeola Congenita En Yangon, Myanmar

Introduction Rubella is a common cause of rash and fever during childhood. However, its public health importance relates to the teratogenic effects of primary rubella infection occurring in pregnant women, which can lead to fetal death with spontaneous abortion or to congenital defects in surviving infants. The association between birth defects and rubella infection during pregnancy was first reported in 1941 by Gregg, an Australian ophthalmologist. (1) A later prospective study in the United Kingdom found that 85% of infants born to women who had had rubella during the first 11 weeks of pregnancy had birth defects. (2) Manifestations of congenital rubella syndrome (CRS) in surviving infants may be transient (e.g., low birth weight, purpura), may be permanent structural manifestations (e.g., deafness, congenital heart disease, cataracts, mental retardation) or may be late-emerging conditions (e.g., diabetes, thyroid disorders). (3) WHO estimates that worldwide more than 100 000 children are born with CRS each year, mostly in developing countries. (4) (5) Studies of CRS have been conducted in many parts of the world, including several south-east Asian countries. (6) In Myanmar, several rubella sero-prevalence studies from the 1970s that were conducted in urban settings showed high immunity (> 92%) among women of childbearing age, although one study showed only 80% immunity among women aged 15-19 years. (7, 8) While this suggests that rubella infections occurred mostly prior to childbearing age in the 1970s, a case series of children with congenital anomalies seen at a tertiary referral centre that has Yangon's largest neonatal intensive care unit during 1975-78 found that 21 (11%) of 196 children had signs clinically compatible with CRS. (8) The National Immunization Programme in Myanmar provides one dose of measles vaccine to all children when they are aged 9 months; however, the routine immunization schedule does not include rubella vaccine. Measles-mumps-rubella vaccine is available privately but uptake is limited because of the cost. In 2000, Myanmar implemented enhanced surveillance procedures for measles and rubella; these consist of investigating outbreaks of febrile illnesses with maculopapular rash in people of all ages. The National Health Laboratory tests serum specimens from 5-10 cases for each outbreak: specimens are tested for measles-specific IgM and if they are negative, they are tested for rubella-specific IgM. (9) Given the lack of information on the burden of CRS in Myanmar, a prospective surveillance study was undertaken, using both molecular and serological tests to confirm the diagnosis. Methods Active surveillance From 1 December 2000 to 31 December 2002, active surveillance for CRS occurring in children aged 0-17 months was conducted in Yangon, Myanmar, at all 13 hospitals providing paediatric services, including: specialist ophthalmology; ear, nose and throat; and obstetric hospitals, and at two private clinics. Meetings were held with administrators and physicians at each study site, and a study coordinator (usually a paediatrician) was appointed. The coordinators were provided with posters that displayed the definitions of CRS cases, study forms, information on the availability of laboratory tests, and details on how to contact the study laboratory. Each month the study coordinators were contacted to ensure that all suspected CRS cases had been reported. In August 2001 and July 2002, one-day workshops on CRS were held for physicians at participating hospitals. In addition, information on CRS was presented at national and regional medical conferences, and a briefing on rubella and CRS was included in continuing education materials for physicians provided by the National Medical Association. Ethical procedures The study protocol was reviewed and approved by the Ethical Committee on Medical Research Involving Human Subjects, Department of Medical Research (Lower Myanmar), Yangon, and the WHO Secretariat Committee on Research Involving Human Subjects, Geneva, Switzerland. …