Skip to Content
Newborn Screening Ontario

About NSO

Newborn Screening Ontario (NSO), located at the Children’s Hospital of Eastern Ontario (CHEO), is the provincial program that coordinates newborn screening in Ontario, Canada. 

This section of our website will provide you more information about us, our vision and governance.

About NSO


The Infant Hearing Program will refer babies to audiology as part of the follow up services they provide. 


What are the Infant Hearing Program services?

The Infant Hearing Program is a program that:

  • monitors children born with risk factors for permanent hearing loss.
  • provides audiology assessment and intervention services including hearing aid and other assistive device fitting, evaluation, and monitoring to infants who are identified with permanent hearing loss (PHL)
  • provides supports and services needed to develop language and literacy skills


Why do babies need to see Audiology?

If a baby has had a normal hearing assessment, they will be monitored by audiology for hearing loss which can occur later.  If a baby has confirmed hearing loss, the audiologist will help create a plan for the baby’s language and literacy development, and provide intervention services including hearing aids, cochlear implants and other assistive device fitting if needed.


How often do babies need to see Audiology?

If a baby has confirmed hearing loss, they will be assessed at least every 3 months for the first year, every 6 months for the second year, and once a year afterwards.

If a baby has had a normal hearing assessment and a risk factor for hearing loss has been identified, they will be assessed every 4 months for the first year, then at 18 months, 3 years and 5 years.

Ear, Nose and Throat

Ear, Nose and Throat (ENT) Doctor or Otolaryngologist

What is the ENT clinic?

In the ENT clinic specialists examine the structure of the ears and will review the function of the ears including hearing and balance.  They will look for possible causes of the hearing loss.  If hearing aids are recommended, they will write the prescription (medical clearance). Sometimes they will recommend surgical treatments for hearing loss.


Why do babies need to see ENT?

Babies will be referred for an ENT appointment if they are confirmed to have hearing loss.  The ENT specialists will assess for other potential causes of hearing loss. Further testing may be discussed and arranged as necessary.  As well, they will talk about treatment options that may be available, such as hearing aids and cochlear implants as well as provide medical clearance for the use of such devices.


How often do babies need to see ENT?

The frequency with which a baby sees ENT will depend upon whether or not there are treatment options available.  All children will at least undergo an initial assessment by the ENT specialist.  Depending on the circumstances, follow up may be on an as needed basis or may occur at a variety of intervals (e.g. every 6 months to a year).

Ear, Nose and Throat

Asymptomatic with cCMV infection

Asymptomatic means that there are no signs or symptoms of cCMV infection.  However, there is a chance of developing problems, primarily hearing loss, in early childhood.


How often will a baby be followed?

If a baby has been found to have no symptoms of cCMV infection and/or lives in a remote area, their care may be transferred to a local community pediatrician for continued monitoring.  They will be checked on a regular basis by their community pediatrician until the age of 6 years.  However, if there are any concerns, their doctor should be contacted ahead of their scheduled appointment.


What investigations will be recommended on an ongoing basis?

The baby’s doctor will assess him or her similarly to other children – enquiring about achieving their developmental milestones, asking about any concerns with hearing, vision and balance, and checking their growth (head growth, weight, height).  It will also be very important that they have regular hearing testing with Audiology, in order to find any hearing problems as soon as possible and allow early treatment.


Are there any signs/symptoms to look for?

Even if a baby had a normal hearing assessment, they are still at increased risk (7-15%) to develop hearing loss.  Due to this increased risk, they will be monitored regularly by Audiology throughout childhood.


Are there other specialists that a baby with cCMV should see regularly?

Children will be followed by Audiology until the age of 6 years through the Infant Hearing Program (IHP).  If their doctor notes any concerns with their hearing, vision or developmental milestones, they may make referrals as needed to other specialists.

Symptomatic with cCMV infection

What does being symptomatic with cCMV infection mean?

The majority of babies with cCMV infection never develop symptoms of the infection.   If a baby is described as having symptoms of cCMV infection, they could have already had or may currently have one or more of the following features:

·         Jaundice (yellow skin and eyes)

·         Small head (microcephaly)

·         Changes in the brain (scarring or other problems)

·         Small size during pregnancy or at birth

·         Enlargement of the spleen and/or liver (hepatosplenomegaly)

·         Seizures

·         Inflammation of the eye (retinitis)

·         Hearing loss

·         Rash from low platelets

·         Inflammation of the liver (transaminitis)


In babies who had symptoms at birth, they are at risk of going on to have:

·         Developmental and motor delay

·         Seizures

·         Vision loss

·         Hearing loss

·         Balance impairment


Some babies will have only one symptom (such as hearing loss).  Others may have many symptoms.  As there are future risks associated with having cCMV infection, follow up and detection of problems soon after they occur leads to a better outcome for the child.


What are the treatment options?

Some babies with symptoms of cCMV infection will benefit from treatment with valganciclovir.  Valganciclovir is an antiviral medication.  The ID doctor will talk about valganciclovir and whether or not they feel there would be a benefit from treatment.


Are there any signs/symptoms to look for?

If there are concerns regarding the health of a baby, as it relates to cCMV infection, in between scheduled appointments, please contact the ID clinic or primary care physician.

IHP Lead Agencies

The Infant Hearing Program is delivered through 12 Lead Agencies in the province of Ontario.  IHP Lead Agencies are responsible for delivering the program in accordance with provincial guidelines in a manner which reflects regional and local needs.  Infants have their hearing screening done by the Lead Agency corresponding to their home address in most cases.  In some instances this may be a different Lead Agency if they are admitted to a hospital in another Lead Agency jurisdiction (ie baby lives in Kingston but is admitted to the Hospital for Sick Children). For more information about the Lead Agencies or to obtain contact information, please click here.

IHP Lead Agencies

Screen Positive Information for HCP

Some of the content from this website is available to open as a printable PDF document:

Additional information about the Follow-Up Centre Infectious Diseases Clinics and the Infant Hearing Program Lead Agencies can be found in the subsequent sections of the website.

Screen Positive Information for HCP

cCMV and Hearing Loss

Congenital CMV infection is the most common cause of non-hereditary hearing loss in children.  It is estimated that cCMV infection accounts for ~25% of hearing loss in chlidren by the age of 4 years. 

It is unknown why the virus causes hearing impairment in some children but not others.  The chance of developing sensorineural hearing loss with cCMV infection is 30-50% for symptomatic children and 8-12% for asymptomatic children.

The hearing loss associated with cCMV infection can:

  • affect one or both ears
  • affect some or all pitches
  • be mild to severe
  • be congenital or present later
  • be progressive and fluctuating

The Infant Hearing Program (IHP) has guidelines in place for children confirmed to have cCMV:

  • Children with cCMV who have confirmed hearing loss will be assessed at least every 3 months for the first year, every 6 months for the second year, and once a year afterwards by IHP audiology
  • Children with cCMV who have a normal hearing assessment will be assessed every 4 months for the first year, then at 18 months, 3 years and 5 years by IHP audiology.
cCMV and Hearing Loss

Hearing Loss Risk Factors

There are 3 main risk factors for congenital hearing loss:

  1. Genetic (inherited) factors account for ~50% of hearing loss present at birth (congenital) with autosomal recessive hearing loss accounting for the majority of these.  
    • Autosomal recessive hearing loss is inherited from both parents – often with no one else in the family having hearing loss, including the parents.
  2. Non-genetic factors (such as congenital cytomegalovirus infection) account for ~25% of congenital hearing loss.
  3. Other causes, such as severe prematurity, certain syndromes, or other risk factors, account for the remaining ~25%
Hearing Loss Risk Factors