Highly pathogenic H5N5 avian flu has been detected in a backyard poultry flock in Newfoundland and Labrador, according to information submitted by the Canadian Food Inspection Agency (CFIA) to the World Organization for Animal Health (WOAH), as well as in UK seals.

The poultry outbreak at Gander Bay began on January 15 and killed all 34 birds at the location. Tests at the CFIA National Centre for Foreign Animal Disease confirmed H5N5 and found that the virus is similar to European-like viruses that came to Canada by the Atlantic flyway. The viruses have fully European H5N5 genome segments.

Canada has previously reported H5N5 in wild birds and mammals, including wild raccoons found dead on Prince Edward Island in May 2023. The pace of H5N5 detections in Europe has picked up, including a recent detection in a cat in Iceland. 

Gray seals infected near Norfolk in the UK

In other H5N5 developments, the UK Department for Environment, Food, and Rural Affairs today confirmed the detection of H5N5 in two grey seals found near Norfolk. The United Kingdom is among six countries that have reported H5N5 in birds and mammals since the first of the year, which, alongside Canada and Iceland, also includes Norway, Greenland, and Germany, according to Avian Flu Diary, an infectious disease news blog.

WOAH has warned of unprecedented genetic variability in avian flu subtypes in wild birds and poultry across the world, creating epidemiologic challenges.

China has reported two more human infections involving H9N2 avian flu, and, unlike most earlier patients, the latest are adults, according to a weekly avian flu update from the Hong Kong Centre for Health Protection.

The developments follow two H9N2 reports from China last week, involving a child and a teen who were from Hunan province.

Both patients from Guangdong province

The newest patients include a 72-year-old woman from Guangdong province whose symptoms began on December 26, 2024. The second patient is a 56-year-old woman from the same province who became ill on January 20, marking the second case of the new year.

The report didn't say how the patients were exposed, but H9N2 is known to circulate in parts of Asia, including China, and many earlier patients had contact with poultry or poultry environments.

Illnesses in children are typically mild, but more severe illnesses and deaths have been reported in the past. 

In an encouraging development in Uganda's Ebola Sudan outbreak, all eight patients who were hospitalized for treatment have been released from medical care after testing negative for the virus twice in tests conducted 72 hours apart, the World Health Organization (WHO) regional office for Africa said today.

The patients were receiving treatment in the capital city Kampala and in Mbale. Contact monitoring is still under way for 216 people who are at quarantine facilities located throughout the country.

Kasonde Mwinga, MD, the WHO's representative in Uganda, said the discharge of patients are an important milestone in efforts to control the virus. "While we welcome this positive step, we remain steadfastly on course, working with our partners to support the government to halt this virus and end the outbreak."

The outbreak began in late January and marked Uganda's first since 2022 and the world's ninth involving Ebola Sudan. Five of the earlier outbreaks had been in Uganda, which is known for its skill in battling the virus. 

Death rate much lower than in earlier outbreaks

So far, the outbreak total stands at nine cases and one death, which involved the index patient, a 32-year-old male nurse who had worked at a referral hospital in Kampala. The case-fatality rate (CFR) stands at 11.1%, which is much lower than the CFR of 41% to 100% seen in earlier outbreaks involving Ebola Sudan.

Uganda's latest outbreak triggered a swift response from health partners, including the WHO, which deployed 47 experts, delivered 7 tons of emergency medical supplies, and took several other steps to support the country's response. The outbreak also saw a quick launch of a trial of a candidate Ebola Sudan vaccine, which is from the International AIDS Vaccine Initiative, a nonprofit vaccine research organization based in New York City.