Louisiana is the latest state to report a possible case of bird flu in a human, according to the Louisiana Department of Health (LDH).
This brings the total number of human cases of avian influenza A (H5N1) up to 61, combined with data from the Centers for Disease Control and Prevention (CDC).
California remains the state with the most bird flu cases in humans, with 34 confirmed by the CDC, while Colorado comes in second with 10.
Five other states have at least one case: Michigan, Missouri, Oregon, Texas and Washington.
The CDC maintains that the risk to the general public is low -- but Dr. Maria Van Kerkhove, Director of Epidemic and Pandemic Threat Management at the World Health Organization (WHO), said at the United Nations Geneva Press Briefing on Tuesday that the risk to farmworkers and those exposed to infected animals was low-to-moderate.
The individual in Louisiana, currently hospitalized with bird flu, is believed to have come into contact with sick and dead birds that may have been infected with bird flu, before getting sick themselves.
Currently, humans become sick with bird flu after exposure to animals, such as wild birds, poultry or cattle.
"Although it is difficult for any virus to move from one species to another, influenza A viruses are particularly good at it -- most often causing one-off 'spillover' infections but occasionally adapting to spread effectively in a new host species," Professor Ed Hutchinson, a virologist at the University of Glasgow Centre for Virus Research, told Newsweek.
"In the late 1990s, an H5N1 strain of highly pathogenic avian influenza (HPAI) began spreading in birds, and began causing repeated spillover infections of other animals, including humans."
He explained that a variant became particularly good at spreading in 2020 and recently became fully adapted to cows in the U.S., leading to outbreaks in cattle.
CDC data indicates that 37 of the U.S.'s human bird flu cases are linked to exposure to cattle, 21 to poultry and two from unknown sources -- not counting the Louisiana case.
The U.S. currently has bird flu outbreaks in poultry in 49 states and in dairy cows in 16 states. The bird flu outbreak among wild birds is global.
The risk to humans right now might be low, but Professor Moritz Kraemer, from the Pandemic Sciences Institute and Department of Biology at the University of Oxford, told Newsweek: "We are only a single mutation away from H5N1 potentially shifting from avian to human specificity."
Hutchinson explained: "When an influenza virus from a different animal adapts to spread effectively among humans, the result is a pandemic.
"At the moment, there is no indication that this has happened for H5N1, and we do not really know enough about this new H5N1 strain to confidently assess how likely it is to make that jump.
"But the more encounters the virus has with humans, the more chances it has to adapt to growing in them."
Hutchinson said that surveillance and taking steps to limit human contact with infected animals, were important to prevent this risk from increasing.