AUSTRALIA lacks a comprehensive approach to screening of infants for congenital cytomegalovirus (CMV) screening, and most infected infants go undiagnosed, according to the authors of a Perspective published today by the Medical Journal of Australia.
“Congenital CMV infection is a significant if poorly recognised public health issue,” wrote the authors, led by Dr Allison Reid, a PhD candidate at the University of Western Australia.
“The virus is a leading cause of developmental disability and a common cause of permanent hearing loss in infants. Ninety percent of infected infants remain asymptomatic, making universal screening (testing all infants) difficult to justify,” Reid and colleagues wrote.
“Despite the high asymptomatic rate, the significant prevalence and infectivity result in congenital CMV affecting more children than other disorders universally screened for in newborns in Australia.”
There is no CMV vaccine, despite it being ranked the highest priority vaccine to develop relative to economic burden and years of life and disability that would be saved.
“Diagnosis and treatment of congenital CMV infection are time critical,” Reid and colleagues wrote.
“In order to distinguish congenital and acquired CMV, testing must be completed by day 21 of life. This narrow window, limited congenital CMV awareness and the lack of a comprehensive approach across Australia means most cases go undiagnosed, and for symptomatic children this may represent a lifelong disability of unknown cause.
Testing infants’ hearing via newborn hearing screening is an example of universal newborn screening programs established in Australia.
While universal screening for congenital CMV is “possible but untried”, targeted testing identifies those at high risk for a condition and focuses testing on this group.
“Targeted congenital CMV testing typically uses a failed newborn hearing screening as a high-risk indicator,” wrote Reid and colleagues. “[It] is a feasible approach to identifying affected infants and a move towards improved outcomes.
“The current approach to the diagnosis of congenital CMV infection across Australia is inadequate. Subsequently, affected infants regularly fail to receive best practice care.
“Despite comprehensive newborn hearing screening programs, many children with sensorineural hearing loss are not routinely screened for congenital CMV and this is arguably an important gap within the program.
“The limited level of awareness of the virus among parents, clinicians and policymakers may be the biggest obstacle to effectively addressing congenital CMV in Australia,” they concluded.1
- Cate Swannell