The Centers for Disease Control said 41 people, two more than previously confirmed, have contracted bird flu in the seven months since the viral disease first was identified in dairy cattle in Texas. One of the new cases was in California and the other was listed as “jurisdiction pending” in a CDC tally.
All of the infections have resulted in mild symptoms and the patients responded to treatment. The CDC said its research using the material from the first human case, a dairy worker in Texas, indicated that “this virus has the potential to cause severe illness in people” but has not become more transmissible through the air. The Texas samples had “two mammalian adaptive mutations” not seen in the other H5N1 viruses found in dairy cattle. “These findings suggest the importance of continued surveillance to monitor these kinds of changes in circulating A (H5N1) viruses,” said the CDC.
In the CDC research, which used ferrets, all ferrets that were infected through direct contact with an infected ferret died. The agency said the results “reinforced the importance of protective measures among people with exposure to infected animals and for public health and agriculture communities to continue to work together to contain this.” Preliminary results of the research were released in June.
Meanwhile, the Oregon state Health Authority said that three people infected by the bird flu virus briefly traveled to Oregon from Washington State last week. “The cases returned to Washington and continue to be monitored by Washington public health staff until 10 days following their last exposure,” said the Oregon agency. The individuals “were monitored by public health while in the state.” Washington State has reported nine poultry workers were infected with bird flu while culling chickens.