Rubella and congenital rubella syndrome.

Rubella and congenital rubella syndrome* 1. Brief description of the condition/disease Rubella usually presents as a mild or asymptomatic infection in adults and children. However, rubella infection in pregnant women, especially durmg the first trimester, can rcsult in mnscarriage, stillbirth, or the constellation of birth defects known as congeni- tal rubella syndrome (CRS). The most commonly described CRS anomalics Lnclude ncrve deafness. cataracts. cardiac anomalies. and mental retardation. 2. Current global burden and rating with the overall burden of disease The global burden of rubella and CRS is undefined. Rubella is endemic in most countries In a survey conducted by WHO in 1995, 78 of 214 countries (36%) had a national policy of rubella vaccination. Analysis of publisbed serosurveys in several devel- oping countries indicated a wide range of serosus- ceptibility in reproductive-aged women Thus, the potential for outbreaks of rubella and subsequent CRS exist More than 20000 infants arc born with CRS each year in the Americas in the absence of major epidemics. Globally, an estimated 236000 CRS cases occur every non-epidemic year in devel- oping countries. In countries wvith endemic rubella in the prevaccine era, the rate of CRS was I per 1000 live birtlhs. 3. Feasibility (biological) of elimination/eradication Use of the established criteria for teasibilitv of eradi- cation by the International Trask force for Disease Eradication indicates that rubella and CRS can be eradicated. Since the introduction of rubella vaccine in the USA in 1969, the incidences of rubella and CRS have decreased by 99%. The following factors favour climination/cradi- cation of rubella/CRS: humans are the only reservoir for rubella; rubella vaccme is highly effectlvc ni pre- venting rubella and CRS, and a combination vaccine with measles exists; and because of this combmation * Contnbuted by Susan E Real, Cenlers for Disease Control and Prevention, Atlanta GA, USA vaccine, rubella climination/eradication can be coni- bined with the already exsting measles eliminatioiln eradication efforts. 4. Estimated costs and benefits of elimination/eradication Rubella and CRS prevention is cost-effective. In the USA in 1982. the estimated litetime cost of caring for a child with CRS was over UIS$ 200000. A cost- benefit analysis tor rubella vaccune mn the USA con- ducted in 1992 demnonstrated a ratio of 11.1 :1 when considering direct and indirect costs. 5. Key strategies to accomplish the objectives The key strategies for countries Nvith no rubella/CRS survcillance or rubella vaccination programme in- clude: establishmient of surveillance for iubella and CRS: implementation of a national rubella vaccina- tion programmc, particularly ensuring high level protection of reproductive-aged wonien as a mcans of direct protection; and pronmpt outbreak-control measures. Countries that have an established rubella and CRS surveillancc systcm and national rubella vacci- nation programnme should include maintenance of high vaccination levels in preschool- and school-aged children and young adults (particularly women ot childbeanng age); intensification of diagnosis of and surveillance for rubella and CRS; and piompt con- trol of rubella outbreaks. 6. Research needs Research uiecds include development of rapid and non-invasive laboratory tests for diagnosis of riu- bella/CRS; and determination of the serosuscepti- bility to rubella among reproductive-aged wonmen in developing countries to monitor the impact of the rubella vaccination programmes. 7. Status of elimination/eradication efforts to date The USA has targeted a goal of eliminating in- digenous rubella and CRS by the year 2000. PAHO 156 Bulletn of the World Health Organ,zabon, 1998, 76 (Suppi 2) 156-157 Rubella and congenital rubella syndrome has detemiined it would be premaLurc to establish a hemispheric goal ot rubella elimination, but this could be a logical devclopment as progress continues with measles elimination 8. Principal challenges to elimination/eradication Challenges include establishing rubella and CRS as a priority in many developing countries: depending on the vaccination strategy iinplcmnented in countries, 30-40 years may be required for eradication/elimina- lioin of CRS: and lack of financial resources in many countries to sustain a vaccination programme bc- cause of the added cost ot the rubella component of the vaccine and the necessity to ensure protection in reproductive-aged women. WHO Bufleln OMS Vol 76, Suppi 2 1998 157