Congenital CMV international guidelines are needed to guide diagnosis, prevention and management

Cytomegalovirus (CMV) is the most frequent infectious cause of severe congenital malformation in developed countries. In this edition of the journal, Gunkel et al. (1) discuss knowledge and practice amongst 63 Dutch paediatricians and obstetricians in relation to screening of mothers (infrequently done) and infants (rarely done) for CMV. They examined knowledge, attitudes, screening and the use of antivirals in affected infants. The conclusion that improved recognition of congenital CMV is necessary reflects an increasing body of published work that comes to similar conclusions in the Netherlands (2), in the USA (3,4), in France (5), in Singapore (6) and published most recently in a larger (10 190 subjects) Italian population (7). The recurrent message, including as outlined by Gunkel et al., is that knowledge of congenital CMV is very low amongst specialist obstetricians and paediatricians, primary physicians, parents and the general public. As in the majority of recently published surveys, this study used computer-assisted web interviewing (CAWI). The questionnaires were sent by e-mail to targeted populations of obstetricians and paediatricians, as in the previous study by Korver et al. in 2009 (2), or studies in the USA (4) or France (5). The rates of awareness amongst healthcare providers vary depending upon the specialty – Korver (2) previously reported increased knowledge with more advanced career stage and type of speciality. In the study by Gunkel, awareness was generally higher amongst paediatricians and obstetricians and gynaecologists, and among laboratory physicians (5) than nonspecialists and midwives. Of course, this varies between different measured parameters. In parallelwith these studies, surveys (againusingCAWI)ofpregnant women and university staff (7) suggest lower levels of knowledge about congenital CMV in the nonhealthcare worker population. Again this varies between populations, being higher in tertiary educated individuals than nontertiary educated individuals, lower inpregnantwomen (up to39% in some populations) (8) and varying between countries. This lack of awareness of congenital CMV leads to an important question regarding whether we should undertake (i) screening of pregnant mothers (Gunkel indicate this screening occurs in 27% of the Dutch population); (ii) targeted screening of infants – testing of those with conditions likely due to congenital CMV, most particularly infants with sensorineural hearing loss in the era of universal neonatal hearing screening (UNHS) within developed countries; or (iii) universal screening of all neonates (9). Furthermore, the available methods for diagnosing CMV are increasing significantly, with new serological and molecular methods available for testing mothers, and potentially affected neonates (10). These represent opportunities for screening introduction, with technical performance of the assays increasing with our enhanced knowledge of congenital CMV pathogenesis. The performance of tests of neonatal blood screening cards (NBSC), Guthrie’s or dried blood spots may further improve with new extraction and detection methods, although to date NBSC testing has been of lower than ideal sensitivity. However, it may be that some of the variability in different studies between CMV rates on testing NBSC (10,11) may be reduced or disappear with improved technology, particularly that for extraction of nucleic acids from solid phases. So what is to be done? Gunkel et al. suggest improved recognition of congenital CMV, they suggest reaching consensus on management, development of international guidelines, and they stress the need for screening of neonates. Whether neonatal screening should be targeted to high-risk populations or universal is uncertain, although Gunkel et al. recommend universal neonatal screening. In relation to this,