Vietnam has reported its first human infection with a low pathogenic avian influenza (bird flu) A(H9N2) virus, according to the Centres for Disease Control and Prevention (CDC).

This is a different sub-type of avian influenza than the highly pathogenic avian influenza (HPAI) A(H5N1).

The infection in Vietnam occurred in an adult with an underlying medical conditions who was hospitalised on March 16, 2024, and as of Friday, April 12, the patient still remains in hospital for monitoring and treatment.

Human infections with A(H9N2) viruses have been reported in more than 100 people since 1998 in China, and in Hong Kong, Bangladesh, Cambodia, Egypt, India, Oman, Pakistan, and Senegal.

A(H9N2) viruses are the most commonly identified avian influenza viruses in Vietnam, representing more than 50% of all sub-typed detections from live bird markets in that country, research from the CDC proved.

The CDC stated that human infections with avian influenza viruses are “not surprising” in people with direct exposures to sick or dead birds, or other animals in areas with endemic spread among wild birds or other animals.

Bird flu in dairy herds

Meanwhile, in the United States, there has been over 25 reported cases of HPAI in cattle confirmed by the U.S. Department of Agriculture (USDA) and Animal and Plant Health Inspection Service (APHIS) on Friday, April 12.

The Maryland Department of Agriculture issued on Wednesday, April 10 an order restricting movement of dairy cows into Maryland from states with confirmed outbreaks of HPAI in their herds.

Maryland agriculture secretary, Kevin Atticks said: “This order acts as another layer of protection for our Maryland farmers and agriculture industry partners.”

Although, there have been no detections of HPAI in cattle in Maryland, producers are being reminded to practice strong biosecurity.

To prevent the spread of avian influenza, the Maryland Department of Agriculture advises poultry and livestock owners to adopt the following biosecurity measures:

  • Make biosecurity a daily practice to safeguard your agricultural animals;
  • Stay vigilant for signs of illness and be familiar with the symptoms of infectious diseases;
  • Report any suspected agricultural animals to the Maryland Department of Agriculture;
  • Commercial chicken growers and backyard flock owners can seek guidance by emailing their questions to the Maryland Department of Agriculture.

The U.S. Food and Drug Administration has stated that there is no concern about the safety of the milk supply as the products are pasteurised before entering the market.

However, dairies are required to only send milk from healthy animals into processing for human consumption.