As part of the Clinical Services Branch of the City of Milwaukee Health Department and the largest local public health laboratory in the state of Wisconsin, the Milwaukee Health Department Laboratory (MHDL) plays a vital role in protecting the health of the community. MHDL primarily fills this role by providing real-time disease surveillance and responding to threats of public health concerns and/or emergencies, such as the current COVID-19 pandemic. As a trusted partner to local health care providers, academic institutions, and community organizations, MHDL has been committed to not only providing timely, accurate, fee-exempt COVID-19 testing to a variety of clients, but also to supporting public health education, training and services to better equip community partners to perform COVID-19 testing as well.
The MHD Laboratory offers nucleic acid amplification testing (NAAT) for the diagnosis of active COVID-19 infection and IgG antibody test to evaluate for exposure to SARS-CoV-2. COVID-19 testing criteria for public health laboratories has been expanded to include specimens from high risk and underserved populations with COVID-19 symptoms with poor access to testing in other settings (i.e. underinsured, patients at Federally Qualified Health Centers, homeless patients, migrant workers, congregate settings etc.). Complete testing criteria defining which specimens may be tested at MHDL or WSLH is described in HAN #9.
We ask that you please contact us at (414) 286-3526 or [email protected] with any questions regarding testing, and to notify us in advance of expected specimen submissions.
| NOTE: Patients should contact their healthcare providers for testing options. MHDL DOES NOT collect specimens for COVID-19 molecular diagnostic or IgG serology testing. |
The Milwaukee Health Department Laboratory (MHDL) continues to offer fee-exempt COVID-19 NAAT testing utilizing the CDC 2019-Novel Coronavirus (2019-nCoV) real-time RT-PCR Diagnostic Panel along with other authorized molecular tests under the Food and Drug Administration’s (FDA) Emergency Use Authorization (EUA). These tests are intended for the qualitative detection of nucleic acid from 2019-nCoV in respiratory specimens to help in COVID-19 diagnosis.
For NAAT COVID-19 testing, MHDL is utilizing a variety of platforms including EUA assays performed on the Aptima SARS-CoV-2 assay on the Hologic Panther platform, Xpert Xpress SARS-CoV-2 assay on the Cepheid GeneXpert platform, and the CDC 2019-nCoV real-time RT-PCR diagnostic panel. These testing platforms have equivalent sensitivity and specificity performance characteristics. More information about these platforms can be found at the links below:
All NAAT test requests must include the MHDL Microbiology Requisition form, H-445. Please check “SARS-CoV-2 NAAT” under the Molecular Testing section and complete the required highlighted fields (Appendix 1a). Acceptable specimen types include upper respiratory specimens in both viral transport media (VTM)/universal transport media (UTM) and saline, as well as lower respiratory specimens. Both nasal and nasopharyngeal (NP) swabs are acceptable upper respiratory specimen types. Please refer to Appendix 2a for nasal swab collection instructions, and Appendix 2b for NP swab collection instructions.
NAAT specimens transported within 72 hours of collection may be stored at 2-8°C and shipped on cold packs. If unable to transport the specimen for receipt within 72 hours of collection, store specimens at -70°C or below and ship on dry ice.
NAAT Specimen Rejection Criteria
- Dry swabs and/or those not submitted in VTM, UTM, VCM transport media or equivalent
- Specimens received at room temperature and not submitted on cold packs or dry ice
- Unfrozen specimens received at the MHDL >72 hours after collection
Please see our COVID-19 Specimen Collection Guide for more detailed information on specimen collection and transport.
Additional Resources
Infectious Diseases Society of America Guidelines on the Diagnosis of COVID-19
MHDL is also offering fee-exempt SARS-CoV-2 IgG antibody testing, which is recommended in individuals at least 10 days post-symptom onset or following exposure to individuals with laboratory-confirmed COVID-19. Patients tested prior to this time may be negative for SARS-CoV-2 IgG antibodies. Therefore, molecular testing is recommended for diagnosis of COVID-19 in symptomatic patients.
The Abbott ARCHITECT SARS-CoV-2 IgG assay offered at MHDL has been evaluated by the manufacturer and the FDA in partnership with the National Institutes of Health (NIH), the CDC, and the Biomedical Advanced Research and Development Authority (BARDA). Please visit the FDA website, “EUA Authorized Serology Test Performance,” for more information. Additionally, MHDL has verified that this assay performs in accordance with manufacturer claims. More information about this test can be found at the links below:
All antibody test requests must include the MHDL Microbiology Requisition form, H-445. Please check “SARS-CoV-2 IgG” under Serology-EIA section and complete required highlighted fields (Appendix 1b). MHDL is able to accept serum (1-3 mL) and whole blood (EDTA) (5 mL) samples. Specimens can be submitted at room temperature if transported and received within 48 hours of collection. If unable to transport within 48 hours, store at 2-8°C and ship on cold packs.
Antibody Specimen Rejection Criteria
- Serum samples with a volume < 1 mL, or whole blood samples with a volume < 5mL
- Room temperature specimens received at the MHDL >48 hours after collection
COVID-19 IgG Test Interpretation
IgG antibodies are likely to be present in the majority of individuals approximately two weeks after the onset of COVID-19 symptoms. If a specimen is collected too early, antibody tests can yield false-negative results. Detection of IgG antibodies indicates exposure to SARS-CoV-2, but results from antibody testing alone are not enough to determine whether someone is infected with COVID-19. Therefore, PCR testing is recommended for diagnosis of COVID-19 in symptomatic patients. Additionally, it has not yet been determined if the presence of IgG antibodies implies immunity to COVID-19. Both the CDC and MHD encourage individuals who have a positive antibody test to continue to practice social distancing and follow the same precautions that are recommended for the general population.
To submit specimens to MHDL:
- Package as a UN3373 Biological Substance ‘Category B’
- Monday – Friday specimens can be delivered to:
Zeidler Municipal Building, 841 N Broadway St, 2nd Floor, Milwaukee, WI 53202
- Please use your agency’s courier for transporting any COVID-19 specimens to the MHD lab.
- A designated courier parking spot is now available adjacent to the front entrance of the Zeidler Municipal Building, 841 N. Broadway, in the alleyway just south of the building (between ZMB and the neighboring 809 N. Broadway building). Please see Appendix 3 for more information, including photos/signage of the courier parking location.
- If you do not have your own courier or to coordinate deliveries outside of business hours please call MHDL at (414) 286-3526. Please refer to Appendix 4 for after-hours drop off instructions.
Test results will be available within 1-2 days of receipt of specimens by MHDL. Depending on when specimens are received during the day or for significantly higher volume of test requests, turn around time could be longer. All results will be reported to the submitter electronically, except for tests that are routed through MHD from outreach or other sites, which are reported to CD/testing coordinator. Select submitters and Local Health Department (LHD) officials will be notified by phone with any positive results.
In order to ensure rapid and accurate reporting of COVID-19 results, the “Patient Information” section of MHDL Microbiology Requisition form must include AT LEAST Name, DOB, Address, and Sex. Additionally, please ensure that the “Your Facility” section located at the bottom right corner of the form is filled out as completely as possible and reflects the correct phone and fax numbers for results communication. If the report needs to be faxed to multiple locations, please note that in this section. Otherwise, the report will only be sent to the provider whose information is listed in this section.
Results will also be transmitted to the Wisconsin Electronic Disease Surveillance System (WEDSS), and the health department in the local jurisdiction in which the patient resides will be notified.
Please note that it is the provider’s responsibility to communicate any results to patients. Patients should NOT contact MHDL directly for results. MHDL can only give results to the submitting healthcare provider.