Monday, April 10, 2023

Brief WHO WPRO Update On H3N8 Case In Guangdong Province, China


Credit Wikipedia 

#17,397


Its been 14 days since the Guangdong Provincial CDC published a brief notice of the 3rd known human infection with H3N8 (see China: Guangdong CDC Reporting 1 H3N8 Infection (Zhongshan City).  

Details were scant, other than the age, gender, and location of the case. No onset date was provided, and the patients condition was not mentioned.

We get a bit more detail from the following update published over the weekend by the WHO Western Pacific Regional Office (WPRO). 


Between 31 March to 6 April 2023, one new case of human infection with avian influenza A(H3N8) virus were reported to WHO in the Western Pacific Region. The case was a 56-year-old female from Guangdong province with an onset of illness on 22 February 2023. The case was detected through severe acute respiratory infection (SARI) surveillance systems. She was hospitalized for severe pneumonia on 3 March 2023 and subsequently died on 16 March 2023

The patient had multiple underlying conditions. She had a history of exposure to live poultry before the onset of the disease. No close contacts of the case developed an infection or symptoms of illness at the time of reporting.

The environmental samples were collected from the patient's residence and the wet market where the patient was exposed before the onset of illness. The results of testing showed that the samples collected from the wet market were positive for H3. To date, a total of 3 laboratory-confirmed cases of human infection with influenza A(H3N8) virus with one death have been reported to WHO in the Western Pacific Region.

This case is notable because it is the first adult reported to be infected, and the first fatality (although the patient had multiple comorbidities). 

The first two cases occurred roughly a year ago, and more than 1000 km away, in Henan Province (see here, and here).  The first (severe) case was notable in that both the family dog and cat tested positive for the virus as well.  

Last summer we learned that H3N8 had been detected in Hong Kong's poultry (see EID Journal: Novel Zoonotic Avian Influenza Virus A(H3N8) Virus in Chicken, Hong Kong, China), but it apparently produces few clinical signs, making it difficult to detect.   

The authors wrote:

We report a novel influenza A(H3N8) virus in chicken that has emerged in a similar manner and that has been recently reported to cause zoonotic disease. Although they are H3 subtype, these avian viruses are antigenically distant from contemporary human influenza A(H3N2) viruses, and there is little cross-reactive immunity in the human population. It is essential to heighten surveillance for these avian A(H3N8) viruses in poultry and in humans.

Other than a brief mention on the Macao Government Website (basically repeating the Guangdong announcement), there has been almost no mention of this case from official channels. 

China's National Health Commission has not mentioned it, nor has anything been posted on Hong Kong's government website (see below).
 
Null result for H3N8 over past 30 days 


China's state run media was silent for the first 48 hours, but has since published stores reassuring the public that it was `a sporadic case and the risk of transmission is low'. They have shown far more interest in publishing reports of H5N1 (from anywhere, except inside China).

As we've discussed often (see Flying Blind In The Viral Storm) - between the `fog' of the COVID pandemic, and increasing international tensions - our ability to see disease threats around the world has deteriorated over the past few years,

The last H5N6 case we heard about was on March 1st, but it was about a case from December of 2022. Delays of 2 months (or longer) in revealing cases has increasingly become the norm in China (see here and here). Guangdong's H3N8 notification - while 2 weeks after the death of the patient - was actually relative quick for China.

It isn't just China, of course.

Our visibility of MERS-CoV in the Middle East has plummeted since 2020 despite concerns over the the potential for MERS-CoV to recombine with SARS-CoV-2  (see Nature: CoV Recombination Potential & The Need For the Development of Pan-CoV Vaccines).

Surveillance and reporting in many regions of the world are often hampered by a lack of resources - or sometimes deliberately - for economic, societal, or political reasons.

But whether we see it coming or not, the next global public health crisis is probably closer than we think.