We know it can get overwhelming reading about COVID-19 mutations all the time, so allow us to offer you a brief respite. The Chinese National Health Commission (NHC) yesterday reported the first case of H3N8 bird flu in a human – a four-year-old boy from Henan province who fell sick earlier this month.
“[The patient] developed a fever and other symptoms on April 5, and was admitted to a local medical institution for treatment on the 10th due to a worsening of his condition,” says the NHC statement released yesterday.
“On the 24th, the Chinese Center for Disease Control and Prevention conducted a test … the result was positive for the H3N8 avian influenza virus,” the statement continues. “Henan Province carried out medical observation and sampling tests on the close contacts of the child, and no abnormality was found.”
The H3N8 flu strain is fairly common in horses and dogs, and has even been found in seals, but has never been confirmed in humans before. However, some experts believe the strain was behind the so-called “Russian flu” pandemic of 1889-1890 – and that’s “a major concern for the risk of the virus,” Erik Karlsson, deputy head of the virology unit at the Institut Pasteur in Cambodia, told Reuters.
“We need to be concerned about all spillover events,” he warned.
Before falling sick, the statement explains, the boy had lived in very close proximity to a variety of wild and domesticated bird species, including crows, ducks, and chickens. Whole genome sequence analyses of the flu strain reflect this, Nicola Lewis, an influenza expert at the UK’s Royal Veterinary College told Reuters, as they indicate that the H3N8 virus in this human case includes genes from viruses previously detected in poultry and wild birds.
That said, the NHC sees the risk of a large-sale human outbreak as low. Tests on the boy’s close contacts all came back negative, the statement said, and “experts' preliminary assessments believe that H3N8 … is of avian origin and has not yet had the ability to effectively infect humans.”
“This outbreak is an occasional bird-to-human cross-species transmission, and the risk of a large-scale epidemic is low,” the NHC adds.
While the jump into a human host may provide an opportunity for the virus to adapt new mutations that allow it to spread more easily in mammals, Karlsson explained, this is rare. Quite a few avian flus manage to infect humans, especially in places with large populations of poultry, and not many result in human pandemics.
Just last month, for example, some 2.75 million birds in Wisconsin were killed to stop the spread of a highly lethal form of avian flu. China, meanwhile, has already seen a small but deadly outbreak of the H5N6 strain of bird flu in humans back in January this year, and saw the first known human case of H10N3 just six months before that. The people most often affected are poultry workers, though experts warn that zoonotic transmission of diseases like this is likely to increase as humans further encroach into wildlife habitats.
For now, the NHC recommends people “should avoid contact with sick and dead poultry in daily life, and avoid direct contact with live poultry as much as possible; pay attention to dietary hygiene, and separate raw and cooked food during food processing” – in other words, things we should hopefully be doing (or not doing) already.
On top of that, the statement recommends wearing a mask and seeking medical help if you feel sick – which, given we’re still in the throes of a pandemic, continues to be good advice in general.