Virology

General Virology Testing Information

Specimen requirements

Specimens for same day transportation to the Virology Laboratory should arrive at the Pathology Specimen Reception HRI before 2pm or to the Pathology Specimen Reception CHH before 3.30pm (Monday to Friday), and laboratory specimen deliveries are received in Biological Substance Category B carriers, which conform to UN3373 regulations.

A Virology on-call service for urgent pre-dialysis screening for Hepatitis B and C is available between the hours of 8.00am and 12.00pm (midday) on weekends and bank holidays, to the Renal Department.

The on-call Biomedical Scientist (Virology) should be contacted via HRI switchboard on 01482 875875.

Outside of these hours, or for other departments, the on call Infection Consultant can be contacted by the Consultant in charge of the case via HRI Switchboard on 01482 875875.

All samples require the onset date of illness, symptoms and travel history where appropriate. Request forms and sample labels must contain all the requested information.

It is preferable, and much more successful, to take more than one type of specimen from the patient to establish a viral diagnosis.  Throat swab, faeces and acute and convalescent paired samples of clotted blood for serology should be taken as a basic routine for general virological investigations, with additional samples as deemed necessary.

Time limits for additional examinations

Most serology blood samples are stored for approximately two years – in some instances it may be possible to carry out further serological tests within this time. Please contact the laboratory on 01482 626763 for advice.

Viral Haemorrhagic Fever (VHF)

If VHF is suspected please seek advice from the Infectious Diseases doctor.

In such cases please do not send any specimens to the laboratory without prior discussion with the Consultant Virologist.

Needle Stick Injuries

For needle stick injuries, Health Care Workers must contact the Occupational Health Department or, outside hours must contact the Emergency Department. They must also fill in an accident form. A venous blood sample (gold topped blood tube only) should be sent promptly for storage; other advice will be provided by Occupational Health.

If there is concern regarding HIV, consult the PEP protocol produced by Occupational Health. For non-Health Care Workers assessment should be arranged by visiting the Emergency Department.

The Occupational Health department and the Consultant Virologist must be contacted following any accident involving potential Hepatitis B, Hepatitis C or HIV infected patients or their sample.

Imported Infection / Tropical Viral Screen Requests

Please see snap shot below of an example of the clinical information required for a Colindale request form for a Tropical Screen / Post Travel request:

Colindale request form for a Tropical Screen / Post Travel request

Please note that completion of the relevant proforma by the laboratory is essential and a referral request will be rejected by the referral lab if the “relevant information” is not provided by the requesting clinician.

Test Request Approval

The following requests should always be discussed with the Consultant Virologist before submitting the specimen:

  • HIV Proviral DNA
  • HIV Resistance Genotyping

Serological and Molecular Testing

Blood samples are required for:

  • Viral serology, travel screen and bacterial serology
  • Blood Borne Virus Quantitative PCR
  • Quantitative CMV/EBV/BK PCR
  • Other Viral and Bacterial PCR

Other Molecular Testing

Various non-blood samples are required for:

  • Sexually Transmitted Infection SDA NAAT:
    • Chlamydia NAAT
    • Chlamydia/GC/HSV/TV NAAT (GUM)
  • Routine Respiratory PCR (to include Influenza A and B, RSV, Parainfluenza virus, Human Metapneumovirus, Rhino, Coronavirus, Bocavirus and enterovirus)
  • Other Viral PCR (to include DNA and RNA viruses associated with the GI tract, Skin/Rash,  Eye, Gynaecological and Central Nervous System complications)
  • Urgent MRSA PCR screen
  • Urgent RSV / Influenza A/B PCR screen