Using shared needles for subcutaneous inoculation can transmit bluetongue virus mechanically between ruminant hosts

Area of Science:

• Veterinary Virology
• Epidemiology
• Infectious Disease Transmission

Background:

• Bluetongue virus (BTV) is a significant arbovirus affecting ruminants, transmitted by Culicoides midges.
• High viraemia in infected animals suggests potential for iatrogenic transmission via needle sharing.
• Limited data exists on iatrogenic transmission risks for less invasive inoculation routes like subcutaneous injections.

Purpose of the Study:

• To investigate the risk of Bluetongue virus (BTV) transmission through needle sharing during subcutaneous inoculation in ruminants.
• To determine if BTV can be transmitted iatrogenically without visible blood contamination on needles.

Main Methods:

• Sheep and cattle were used as recipients in experimental inoculation studies.
• Needles used for subcutaneous inoculation were shared between animals.
• Detection of BTV in recipient animals was used to confirm transmission.

Main Results:

• Bluetongue virus (BTV) was successfully transmitted between animals via needle sharing during subcutaneous inoculation.
• Transmission occurred even when needles showed no visible blood contamination.
• The incubation period following needle sharing was longer than reported for direct inoculation or midge transmission.

Conclusions:

• Needle sharing during subcutaneous inoculation poses a risk for Bluetongue virus (BTV) transmission.
• Findings necessitate a review of current veterinary vaccination protocols regarding needle reuse.
• The study highlights potential public health concerns related to pathogen transmission via reused needles in subcutaneous procedures.