Avian - or bird - flu is highly infectious but cases are generally uncommon in humans.
ADVERTISEMENTA person has tested positive for bird flu in the US, health officials reported this week, the country’s second human case.
H5N1 was confirmed in a person who had been exposed to dairy cows thought to be infected with the virus in Texas.
H5N1 is a type of highly pathogenic avian influenza or bird flu. While uncommon in humans, when a person is infected, the mortality rate is about 60 per cent, according to the World Health Organization (WHO).
The Texas patient’s only symptom was eye inflammation or redness, according to the US Centers for Disease Control and Prevention (CDC), which confirmed the case.
The patient has been treated with the antiviral drug oseltamivir which is marketed under the brand name Tamiflu.
This was the second human case in the US, with a person in Colorado who had direct exposure to poultry and was involved in culling infected birds testing positive in 2022.
Risk of bird flu in humans remains ‘low’
The CDC said the risk of H5N1 remains “low” in the US, adding that people with “prolonged, unprotected exposure” to infected birds and other animals such as livestock were at a greater risk of being infected.
US officials had reported the virus was found in dairy cows in Texas and Kansas last week, with unpasteurised milk samples from sick cattle testing positive. They said it appeared to come from wild birds.
The officials emphasised that there was no concern about commercial milk supply with dairies required to send milk from healthy cows. They also use pasteurisation which is proven to inactivate bacteria and viruses.
Seasonal flu vaccines do not protect against H5N1, according to the CDC. The agency also warned that people should avoid unprotected exposure to sick or dead animals.
According to a European Centre for Disease Prevention and Control (ECDC) report from last week, there have been some 888 cases of H5N1 reported in 23 countries since 2004.
The ECDC said that there have been six other cases worldwide this year in Cambodia and Vietnam with one death in each country.
The last European country to report cases of H5N1 in humans was the United Kingdom which reported four human cases last year. These were picked up through asymptomatic surveillance of individuals who were exposed to infected birds.
Between December 2, 2023, and March 15, 2024, there were 227 outbreaks in domestic birds and 414 outbreaks in wild birds across 26 countries in Europe, the ECDC said in its latest report.
