If your patient is calling about COVID-19 symptoms:

If your patient wants or needs to get a COVID-19 test:

Patients can also book a test by calling 289-778-1465, then press 2

Public Health Services (289-778-1465) will continue to connect vulnerable individuals in need of support with the City Emergency Operations Centre (EOC) to facilitate the following:

  • Emergency food delivery for those in self isolation or deemed medically vulnerable who have no other supports such as friends, family or neighbours to assist.
  • Delivery of masks and gloves to individuals identified by PH as COVID positive
  • Arranging transportation to the assessment centres via DARTS for individuals requiring testing for COVID-19

If a patient is homebound,  EMS can do the swab – call Public Health testing number, and it can be arranged.

Updated February 19, 2021

Ontario has updated testing guidelines to prioritize those who are at the greatest risk, while shifting away from untargeted asymptomatic testing, and reducing the number of symptoms on the screen guidance algorithm that triggers testing for children in school or daycare. There is also clear guidance for enabling early return to school/daycare without testing for children who do not match the screening algorithm.

COVID-19 Guidance School Case Contact and Outbreak Management

Patients should be referred to assessment centres for testing if they are:

  1. Showing COVID-19 symptoms (note symptom algorithms for adults and childen below);
  2. Have been exposed to a confirmed case of the virus, as informed by your public health unit or exposure notification through the COVID Alert app;
  3. A resident or work in a setting that has a COVID-19 outbreak, as identified and informed by our local public health unit
  4. Eligible for testing as part of a targeted testing initiative directed by the Ministry of Health or the Ministry of Long-Term Care.

Other people who are not showing symptoms and not eligible for testing as part of groups 2-4 can get tested for COVID-19 at select pharmacies. To find the closest pharmacy, visit Ontario.ca/covidtest.

Current Symptom Reference lists

The Ontario Ministry of Health Reference Document for Symptoms

Summary screening algorithm

COVID-19 Patient Screen Guidance (adults)

Changes were made to the provincial COVID-19 school and child care screening criteria on Feb 16 2021as a response to emerging “Variants of Concern:

Single-symptom screening

Staff, students and children with any new or worsening symptom of COVID-19, even those with only one symptom, must stay home until:

  • They receive a negative COVID-19 test result;
  • They receive an alternative diagnosis by a health care professional; or
  • It has been 10 days since their symptom onset and they are feeling better.

New isolation requirement for household contacts of symptomatic individuals in response to emerging “variants of concern”

All asymptomatic household contacts of symptomatic individuals are required to quarantine until the symptomatic individual receives a negative COVID-19 test result or an alternative diagnosis by a health care professional. If the symptomatic individual does not seek COVID-19 testing, all household contacts must quarantine for 14 days from their last contact with that symptomatic individual.

The criteria for testing in the Screen Guidance below has been superseded by this advice, and an undated version of the COVID-19 Patient Screen Guidance will be provided by the Ministry shortly and will be updated here when it becomes available)

COVID-19 Patient Screen Guidance (children in school or daycare)

Significant symptoms  outlined in the symptom algorithm in the “Patient Screen Guidance” above include new or worsening cough, fever (>37.8), shortness of breath (even when not active), change in taste or smell, loss of smell or taste, chills, new onset muscle aches and fatigue. People may also report unexplained or significant headache, sore throat, difficulty swallowing, pink eye, runny nose or nasal congestion without other known cause, abdominal pain, nausea/vomiting, diarrhea.

Be on the lookout for atypical symptoms  in children, seniors >70years, and people living with a developmental disability. These may include delirium, unexplained or increase in falls, acute functional decline, exacerbation of chronic conditions.  Symptoms and signs in young children may include lethargy and/or decreased feeding (if no other diagnosis), croup and unexplained tachycardia (using age specific tachycardia reference ranges for children). Children have also been reported as presenting with lesions on extremities resembling chilblains / pernio, and rarely with atypical Kawasaki disease (Multisystem inflammatory vasculitis).  

Read the full provincial testing criteria

Read more about pre-symptomatic and asymptomatic transmission from the CEP here.

A patient who screens positive for symptoms of COVID-19 over the phone should be offered a telephone consultation (see Ministry of Health Guidance to Primary Care 09/11/2020) with a primary care provider ideally on the same day, and advised to start self isolating immediately. This discussion should include a thorough history-taking and assessment of symptoms and managing them (see Step by Step guidance in Assessment and Management of COVID).

New isolation requirement for household contacts of symptomatic individuals in response to emerging “variants of concern”

All asymptomatic household contacts of symptomatic individuals are required to quarantine until the symptomatic individual receives a negative COVID-19 test result or an alternative diagnosis by a health care professional. If the symptomatic individual does not seek COVID-19 testing, all household contacts must quarantine for 14 days from their last contact with that symptomatic individual.

Because significant surge in demand for COVID-19 tests resulting long line-ups at testing centres and the increase in phone calls to the public health line, all COVID-19 assessment and testing centres have moved to online booking for prebooked appointments.  Patients can learn more about testing and assessment centres, and how to book an appointment for testing by visiting www.hamilton.ca/coronavirus/assessment-centres.

To support this move to online booking and prioritizing patients at greatest risk, the number of walk-ins tested at the assessment centres will be limited, and residents who come to a testing centre without an appointment may be asked to book one online.

The Public Health Services COVID-19 booking line will remain available for those who do not have access to book online and those who have accessibility needs. Public Health Services’ COVID-19 Hotline is 905-974-9848.

At this point in time, same day testing cannot be guaranteed. Our local testing centres are at maximal capacity and we anticipate lower priority individuals will be waiting 4 days or more for their appointment.  Patient should immediately self-isolate pending test results. Please help patients to understand the need for pre-registration and online booked appointments.

It is essential that we all reinforce that appointments are required.

If your patient qualifies for COVID 19 Testing and is a community-based health care worker, first responder, a child under the age of 4, or is unable to access the mountain drive through testing site, they will book at St Joe’s Assessment centre. (Health care workers within either hospital system will continue to access testing through their occupational health services). Hours 4:00 pm to 8:00 pm, Monday to Friday, Weekends 10:00 am to 2:00 pm.

Any patient who screens positive and is not part of the groups mentioned in  #1 may book at any centre.

The drive through site site is located within the Dave Andreychuk Mountain Arena, 25 Hester Street.  (just off Upper James and south of Mohawk). The hours of operation are 10:00 am to 4:00 pm. The drive through testing site cannot provide testing for children under the age of 4 or those who arrive on foot and these should be routed to the St Joes East End Assessment centre as above

The physicians’ telephone access to PH and SJHH King Street remain but the ability to answer calls is seriously challenged at present. *see hfam email May 19 for family physician numbers for Dave Andreychuk Mountain Arena and St Joe’s Assessment Centre * 

*note backline numbers cannot be included in this open website. If you need the email to be resent, please send your request to Lisa Waite, (lwaite@stjosham.on.ca)

Public health continues to contact all people with positive results.  If their screening process indicates extra significance to a negative result (e.g., a person living in a shelter), those people may also be contacted.  People who have been tested and have a health card can access the portal for their results.  (OLIS and Clinical Connect may also be used by providers seeking results. 

Guidance on clearance can be found here:

A recent practice pointer article from the BMJ provided useful “what you need to know” summary for interpreting test results in primary care:  

  • Interpreting the result of a test for covid-19 depends on two things: the accuracy of the test, and the pre-test probability or estimated risk of disease before testing  
  • A positive RT-PCR test for covid-19 test has more weight than a negative test because of the test’s high specificity but moderate sensitivity  
  • A single negative covid-19 test should not be used as a rule-out in patients with strongly suggestive symptoms  
  • Clinicians should share information with patients about the accuracy of covid-19 tests 

1. From Lifelabs:

The following limitations of COVID-19 antibody testing should be considered:

  • Positive antibody (serology) test results do not infer immunity and protection from re-infection
  • Serology results should not be used to exclude active infection
  • Antibody testing performed < 3 weeks after onset of symptoms has reduced clinical sensitivity and may lead to false negative results
  • Rare false positive results may be due to cross-reactivity with other coronaviruses
  • Immunosuppressed individuals or those with mild disease may not produce measurable antibody levels
  • Some studies indicate that a small percentage of people infected with SARS-CoV-2 (<4%) do not have detectable antibodies.
  • The COVID-19 antibody test currently offered by LifeLabs cannot detect antibodies generated after vaccination.

2. From MOHLTC: COVID-19 Provincial Testing Guidance Update V. 13.0 August 25, 2021

Laboratory-based serology testing: detects antibodies to SARS-CoV-2

Purpose: Serology testing is available for clinical use under specific clinical indications:

  • Patients presenting with symptoms compatible with Multisystem Inflammatory Syndrome in Children (MIS-C) or Adults (MIS-A) who do not have laboratory confirmation of COVID-19 by molecular testing.
  • Testing may be considered for patients with severe illness who have tested negative for COVID-19 by molecular testing and where serology testing would help inform clinical management and/or public health action. Serology testing for these patients requires consultation and approval by the testing laboratory.

Serology should NOT be used for screening and diagnosis of acute COVID-19 infection, determining immune status, vaccination status.

3. From Public Health Ontario 

Coronavirus Disease 2019 (COVID-19) – Serology

COVID-19 serology should not be used as a diagnostic test, except in very rare circumstances, due to the potential for false negative and false positive results. SARS-CoV-2 antibodies do not correlate with recovery or infectivity. Serology also cannot be used to assess whether a person is immune to COVID-19 or to determine their COVID-19 vaccination status.

Testing Indications

This test is intended for use as an aid in determining if a patient with an adaptive immune response has been previously exposed to SARS-CoV-2. Currently, it is not known whether the presence of SARS-CoV-2 IgG antibodies correlates with immunity. It can take at least 7-14 days from symptom onset to develop a measurable SARS-CoV-2 IgG response with some individuals never seroconverting. In evaluations at PHO, the highest sensitivity of the assay was seen at >14-21 days from symptom onset. Further, the duration of the IgG response is variable, with a reduction in IgG levels and seronegativity in as little as 2-3 months in some patients.  Additional information about COVID-19 serology testing can be found here: What We Know So Far – COVID-19 and Serology Testing.  

In patients with a low pretest probability (e.g. no high-risk exposure or symptoms compatible with COVID-19), there is a risk that a positive COVID-19 serology result is a false positive, even with high test specificity. Conversely, there is an increased risk of a false negative result if serum is taken too early (i.e., <2-3 weeks after symptom onset) or too late (i.e. antibody waning), from a patient with a mild infection, or if the patient is immunocompromised. Given these caveats and significant gaps in our understanding of the immune response in COVID-19, serology testing has very limited clinical value for individual patients. Detection of viral RNA by molecular testing, such as PCR, is the gold standard for diagnosing COVID-19 in suspected patients. If the patient is symptomatic, a respiratory specimen should be tested by COVID-19 PCR Testing. 

Currently, the limited clinical value for individual patient testing precludes the widespread use of COVID-19 serology as a clinical diagnostic tool. It may be considered for clinical use as an adjunct to COVID-19 PCR testing in:

  • Patients suspected to have multisystem inflammatory syndrome in children (MIS-C) or adults (MIS-A) with a negative, indeterminate, or inconclusive PCR test result or who were not tested

Other clinical scenarios of severe illness with negative PCR tests, where serology results may be helpful for clinical management and/or public health action, will be considered following consultation and approval by a PHO Microbiologist before specimen collection. 

Specimens submitted for testing for indications other than MIS-C/MIS-A or without prior approval will be rejected.

Serology should NOT be used for:

  • The diagnosis of acute infection, reinfection, or determining the infectivity of the patient
  • Determining immune status of the patient (i.e. protection against future infection)
  • Determining COVID-19 vaccination status of the patient or serological response to vaccination


SARS-CoV-2 IgG testing should NOT be used to determine a patient’s immune status, vaccination status, or infectivity. Results should be interpreted in the context of clinical and exposure history.

A negative SARS-CoV-2 IgG test result:

  • Does not rule out current or previous SARS-CoV-2 infection
  • If clinical suspicion is high, consider retesting in 2-3 weeks
  • Negative results may occur if the specimen is collected too soon or too late following infection, if the patient is immunocompromised, or if the patient is too young to produce an effective adaptive immune response (eg. neonate)

A positive COVID-19 IgG test result:

  • Indicates recent or prior infection with SARS-CoV-2 virus
  • An individual with evidence of seroconversion over a 4-week interval, regardless of nucleic acid amplification testing (e.g. real-time PCR), is considered a “confirmed” case if the individual has not received a COVID-19 vaccination
  • An individual with antibody detected in a single serum specimen is considered a “probable” case if they have not yet received a COVID-19 vaccination AND had symptoms of COVID-19 AND had a high-risk exposure or epidemiological link AND antibody was detected within four weeks of symptom onset1
  • False-positive results may occur from cross-reaction due to prior infection with other human coronaviruses, including SARS-CoV-1 and certain seasonal coronaviruses (e.g. human coronavirus OC43) 

If the patient is symptomatic, a respiratory specimen should be collected and tested for SARS-CoV-2 using a molecular assay.

There is currently no data available to determine if these commercial assays can or cannot detect IgG antibodies produced in response to infection by SARS-CoV-2 variants of concern (VOCs).  

Leave a Reply