WASHINGTON (AFP) – An elderly patient in Louisiana is in “critical condition” with severe avian influenza, United States (US) authorities announced, the first serious human case in the country as fears grow of a possible bird flu pandemic.
The new case brings the total number of infections in the US during the current 2024 outbreak to 61, as California declared an emergency in order to ramp up its response.
Prior patients experienced mild symptoms and recovered at home. But the severity of the Louisiana case has heightened alarm, echoing similar cases worldwide. Last month, a teenager in Canada was also hospitalised with a severe case of bird flu.
According to the US Centres for Disease Control and Prevention (CDC), the Louisiana patient was exposed to sick and dead birds in backyard flocks.
“The patient is experiencing severe respiratory illness related to H5N1 infection and is currently hospitalised in critical condition,” the Louisiana health department said in a statement to AFP, adding the person has underlying medical conditions and is over the age of 65.
“Over the 20-plus years of global experience with this virus, H5 infection has previously been associated with severe illness in other countries, including illnesses that resulted in death in up to 50 percent of cases,” senior CDC official Demetre Daskalakis told reporters on a call.
“The demonstrated potential for this virus to cause severe illness in people continues to highlight the importance of the joint… US federal response,” he added.
Meanwhile the most populous US state California announced a state of emergency.
“This proclamation is a targeted action to ensure government agencies have the resources and flexibility they need to respond quickly to this outbreak,” Governor Gavin Newsom said in a statement, vowing to expand the state’s monitoring system and support the agriculture sector.
The Louisiana case was confirmed last Friday, according to the CDC. Genetic sequencing revealed that the H5N1 virus in the patient belonged to the D1.1 genotype.
This genotype has recently been detected in wild birds and poultry in the US, and in human cases reported in Washington state and in the Canadian case, in British Columbia province.
The D1.1 genotype differs from the B3.13 genotype, which has been identified in dairy cows, some poultry outbreaks, and human cases with mild symptoms such as conjunctivitis.
A handful of US cases have had no known animal source of infection, including a case in Delaware, the CDC reported on Wednesday.
Scientist at Louisiana State University Rebecca Christofferson told AFP that the lack of robust surveillance makes it uncertain whether more animal-to-human spill overs are going undetected or if asymptomatic human-to-human transmission is occurring.
“I’m not panicking yet,” she said, while emphasising the need for increased vigilance.
