Influenza Surveillance Flags Probable H5 Avian Influenza Case in Delaware

An H5 bird flu case that the US Centers for Disease Control and Prevention (CDC) recently added to its probable list was initially flagged by routine influenza surveillance.

In other developments, federal officials confirmed multiple H5N1 detections in dairy cows, poultry flocks and a few non-agricultural mammals, and Labcorp announced the launch of its molecular test for the virus in humans.

Exposure unknown in Delaware probable cases

Tim Mastro, deputy director of communications with Delaware Health and Social Services, said in an email that the state Department of Public Health identified a possible case of novel H5 during routine surveillance at the state’s public health laboratory, which immediately contacted the CDC for confirmatory testing and guidance.

After several tests on the sample, the CDC notified Delaware health officials that it could not confirm the new influenza A in the case.

The CDC had said a few days ago that the infection meets the case definition for a probable case and that there is no defined exposure. The CDC has now reported seven probable cases. The other six involve people who have been exposed to cows or poultry. The number of laboratory-confirmed infections since the beginning of the year remains at 60, which includes 2 with unknown exposure.

Multiple confirmations in cows, poultry, other mammals

In other developments, the United States Department of Agriculture (USDA) Animal and Plant Health Inspection Service (APHIS) confirmed 7 additional outbreaks in dairy cattleall in California, bringing the state total to 645 and the national total to 860 in 16 states.

APHIS also added two additional confirmations flock of poultrythe one recently noted in Louisiana backyard birds and an outbreak at a commercial turkey broiler facility in Barron County, Wisconsin.

APHIS also confirmed five additional H5N1 detections in mammalall with sample collection dates between the end of October and the first week of December. They include a house mouse and a house cat from Utah’s Cache County, where outbreaks in dairy cattle and a laying farm were reported earlier this fall. The detections also include two mountain lions, one in Arizona and the other in Washington, and a domestic cat in California’s San Bernardino County.

Labcorp launches H5 test

Labcorp today announced that its H5 avian influenza molecular test is now available for doctors to order and can be used to assess potential human exposure. The company said it developed the test with support from the CDC to expand access and testing capacity amid ongoing outbreaks in dairy cattle and poultry linked to a growing number of human cases, some with unknown exposure.

Testing with the Labcorp test requires collection of a nasopharyngeal specimen that is sent to Labcorp for polymerase chain reaction (PCR) testing. The result is reported back to doctor and patient.