Highly Pathogenic Avian Influenza (HPAI) Detections in Livestock

In late March of this year, Highly Pathogenic Avian Influenza (HPAI) was identified in dairy cattle in Texas. Infected cattle show a decrease in feed consumption and rumen motility, respiratory signs including nasal discharge, and an acute drop in milk production. Milk quality may also be abnormal. Some cattle remain asymptomatic. Infected cattle have now been identified in eight additional states: Colorado, Idaho, Kansas, Michigan, New Mexico, North Carolina, Ohio, and South Dakota.

By Federal Order, pre-movement testing is required for lactating dairy cattle being moved interstate, unless being transported directly for slaughter. In addition, lactating dairy cattle presented for unrestricted sale at Arizona livestock auctions must also have a negative HPAI test result, by order of the Arizona Department of Agriculture. 

The AzVDL now offers HPAI testing for dairy cattle at no cost to the producer (USDA covers cost of testing). The requested specimen for testing is 3-10 mL of milk/udder secretions from individual cows. It is important for each quarter to be sampled. Samples must be submitted individually, but up to 5 samples may be pooled by the laboratory. Submitters must have a Premise Identification Number (PIN) in order to submit samples for testing. 

In addition, submitters may choose to test additional cattle on a voluntary basis if they suspect disease due to clinical signs, if they are interested in the disease status of asymptomatic animals, or if cattle have exposed or linked to suspect or confirmed HPAI-positive cattle. Bulk tank milk is not an acceptable sample for lactating cattle which are being transported but may be used for surveillance of lactating herds which are not being transported. Deep nasal swabs may be submitted for non-lactating or higher risk cows for testing. A single sterile swab with at least a 6-inch handle must be used to sample both nostrils. Ensure that the mucosa in the nasal passage is brushed firmly with the swab. After both nasal passages have been sampled, the swab is placed in PrimeStore MTM, BHI, or saline (least preferable). Vigorously swirl the swab in the media, express fluid by pressing the swab agist the side of the tube, and remove the swab. Do not retain the swab in the media. PrimeStore MTM is the only media that can be submitted without ice packs; do not submit dry swabs. Nasal swabs cannot be pooled.

Sick or dead cats or other companion animals near Affected Premises may also be submitted for HPAI testing. Cats are particularly suspectable to H5N1 viruses; cats with neurologic disease and dead cats on affected dairies are widely reported. Brain swabs from affected cats (or whole carcasses) can be submitted. Other domestic animals associated with affected farms showing illness should be tested. 

If you have any questions about sampling or submitting, please contact the laboratory for more information. Additional information for producers and veterinarians may be found from the USDA or the AVMA.