Increase in congenital rubella occurrence after immunisation in Greece: retrospective survey and systematic review
Click below to download PDF document
You will require Acrobat Reader to view file.
Click here for PDF document
In 1993 a major rubella epidemic took place in Greece, which was followed by the birth of a large number of babies with congenital rubella. In this week's BMJ a team of researchers from Athens suggest that this situation arose because vaccination rates among young children were too low.
Dr Takis Panagiotopoulos and colleagues from the Institute of Child Health explain that vaccination of young children for rubella interrupts viral transmission and elevates the age at infection of the non-immunised, because they now have few opportunities to acquire natural immunity. If vaccination coverage is low, this can lead to an increase in the proportion of young adults (including women of child-bearing age) who are susceptible to rubella and thus to an increase in congenital rubella occurrence.
In an accompanying science commentary, Dr Abi Berger explains that in order to achieve 100 per cent protection against a highly infectious disease such as measles in the UK, the uptake of immunisation must be about 95 per cent. This is the concept of "herd immunity" which means that not every single person in a population has to be immunised in order to protect everyone in that population - so long as a sufficient number are immunised, protection will be conferred on everybody - explains Berger.
Panagiotopoulos et al investigated the events leading to the epidemic of congenital rubella syndrome. Their study of the population of Greece found that during the late 1970s (the rubella vaccine had been introduced in 1975) and the 1980s vaccination coverage of children did not reach 50-60 per cent until 1990.
Panagiotopoulos et al suggest that a vaccination programme of young children that doesn't achieve high coverage may increase the risk of congenital rubella syndrome. They conclude that in Greece this was due to inconsistent immunisation policies and that their findings emphasise the need to attain and sustain high immunisation coverage if vaccination of young children is introduced.
Contact:
Dr Takis Panagiotopoulos, Senior Researcher, Department of Social Paediatrics, Institute of Child Health, Athens
Tel: 301-7233-872
Fax: 301-7231-734
tpan@ath.forthnet.gr
Dr Abi Berger, General Practitioner, c/o BMJ Press Office
Tel: 44-0-171-383-6529