Dr. Luch blamed herself for not thinking to examine the boy a day earlier, when she might have saved his life if she had treated his flu.
But her alert and subsequent urgent action demonstrated the strength of Cambodia’s disease tracking system and its importance to the global biosurveillance system.
It is the culmination of years of international and local investment, training and public education. It shows how frontline work in low-income countries is becoming increasingly important to global systems for detecting zoonoses – pathogens that spread between animals and humans, as Covid-19 does. The goal is to identify and contain them, buy time to produce enough vaccines or drugs to treat them, or start a frantic mission to develop something new.
growing threat
H5N1 is one of many viruses that cause influenza in birds. It emerged in Hong Kong in 1996 and has since evolved into multiple versions, causing outbreaks in wild and farmed birds and occasionally transmitting to humans.
In 2020, a new, particularly deadly virus spread along migratory routes into parts of Africa, Asia, and Europe, attracting the attention of scientists.
By 2022, it had reached North and South America and was killing wild and domestic animals, including livestock and marine mammals.
So when Cambodia reported two people infected with H5N1 in February 2023, scientists were alarmed. Is this a new version of the virus returning to Asia and killing people? Although scientists have found that the virus has been present in birds for years, the country has not had a human case in nearly a decade.
Genetic analysis showed that the virus infecting Cambodians was a familiar subtype and not one from the Americas, which was a relief. Still, last year Cambodia reported 11 people infected with avian influenza, five of whom died, more than anywhere in the world.
Global concerns about the H5N1 flu have grown in recent weeks as the virus was detected in goats and dairy cows in the United States and later in a sick farm worker in Texas.
As the virus spreads between species, scientists worry that the virus could evolve to spread not only from birds to mammals, but also from humans to humans.
