Molecular testing techniques- primarily polymerase chain reaction (PCR) and next generation sequencing (NGS)- have significantly increased the overall sensitivity and specificity of detection and characterization of bacteria and viruses that cause disease. The Molecular Diagnostics and Virology section is heavily involved in supporting many molecular research and development projects, including the development of new PCR assays, and rapidly evolving NGS methods and associated bioinformatics.
The section works in close partnership with the Iowa Department of Public Health to target diseases of public health significance- highly communicable diseases that require intervention to reduce or stop their spread. Among these are legionellosis, viral meningitis, mumps, herpes and chicken pox.
The section also tests specimens related to disease outbreaks, such as whooping cough (pertussis) and norovirus, the primary cause of gastroenteritis outbreaks in Iowa. The Hygienic Lab is the only lab in the state that performs confirmatory norovirus tests. Identification of these pathogens allows state outbreak investigators to target remediation and prevention strategies.
Testing is also performed in support of various surveillance programs in partnership with IDPH, Iowa State University and local public health departments:
- Viral respiratory disease surveillance informs the medical community of when and where influenza is circulating in the state and if strains match the current vaccine.
- Sexually transmitted disease surveillance provides testing for the diagnosis of chlamydia and gonorrhea infections, ensuring patients receive proper treatment to prevent further spread of infection.
- Arbovirus surveillance tests mosquitoes and humans for West Nile virus and alerts public health officials when mosquito-borne illnesses are circulating, allowing them to implement methods of infection prevention.
- PCR testing for Cryptosporidium and Cyclospora surveillance in various food items is conducted in cooperation with SHL's Environmental Microbiology section. Additionally, the section supports molecular testing for the Food Emergency Response Network (FERN).
HIGHLIGHTS
- Served as a reference laboratory for a clinical trial in a new category of research activity for SHL. This involved performing more than 2,000 shell vial cultures and direct immunofluorescence assays (DFA) for influenza and almost 300 PCR reactions.
- Began the validation and implementation process for a new PCR test that will identify Herpes Simplex Virus (HSV) types 1 & 2, and Varicella Zoster Virus (VZV) from cutaneous and mucocutaneous swabs. Varicella Zoster Virus causes chickenpox and herpes zoster (shingles). Recent reports have shown that VZV is detected in genital swabs at a higher rate than previously thought. The test is a multiplex assay and can detect all three virus types, whereas previous identification of VZV by shell vial culture and direct fluorescent antibody only occurred if specifically requested.
- Began transition from a labor-intensive method of screening for chlamydia and gonorrhea to a fully automated random access platform.
- Validation and implementation began for PCR testing for measles and rubella in-house (rather than sending a sample to a regional Vaccine Preventable Disease Reference Lab).
- Provided testing for Zika, chikungunya and dengue viruses using the Trioplex RTPCR assay. Also tested a record number of mosquitoes for West Nile virus in response to enhanced mosquito surveillance to determine if the mosquito types known to transmit Zika virus are present in the state.
- Zika virus by RT-PCR
- Influenza virus by RT-PCR
- Norovirus by RT-PCR
- Mumps by RT-PCR
- Bordetella pertussis by PCR
