The multistate bird flu outbreak continues to spark concerns across the United States as states have reported additional human cases.

According to the California Department of Public Health (CDPH), six confirmed human cases and five possible human cases of bird flu, also known as avian influenza A, have been reported in California. The CDPH noted that all of the human bird flu cases in the state were caused after individuals had direct contact with cows at nine different dairy farms across the state.

The CDPH explained that all of the individuals affected by the bird flu have experienced “mild symptoms,” such as conjunctivitis and eye redness. The agency also noted that none of the affected individuals have been hospitalized.

At this point, the CDPH believes that there is no concern for human-to-human transmission of the bird flu. The agency said, “Given the amount of exposure to infected cows, evidence continues to suggest only animal-to-human spread of the virus in California.”

The CDPH added, “Additionally, based on CDC’s genomic sequencing of three California bird flu cases, there is no evidence to suggest an increased ability for the virus to infect or spread between people and no known reduced susceptibility to antiviral medications.”

According to a CDC press release, there have been 20 confirmed human cases of bird flu in the United States since April.

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Shira Doron, M.D., chief infection control officer at Boston’s Tufts Medicine Health System, told Fox News that the “higher numbers” of bird flu cases reported in states like California and Colorado are caused by “more aggressive monitoring and case finding efforts in those states.”

Doron told Fox News that when California discovers sick cows, “they monitor exposed health care workers.” Doron added, “The disease has been mostly very mild, so it will only be detected if looked for.”

Doron explained that currently the bird flu outbreak “does not have the potential to become a human pandemic” since there is no evidence of the virus spreading from human to human. However, Doron said that could change in the future.

Doron told Fox News, “Obviously, scientists and public health officials should be concerned, and should take action to limit the spread of this disease in farm animals.”

Sam Scarpino, PhD, Northeastern University’s director of AI and life sciences, also told Fox News that he considers the increased number of human bird flu cases to be “concerning.” He warned, “The more spillovers to humans, the more chances there are for the wrong variant to find itself in a person and spark an epidemic.”