Another person in mainland China has tested positive for H5N6 bird flu, bringing the number of cases so far this year to 20, officials said. Experts have called for increased surveillance to monitor the surge in human cases.
The latest case involves a 56-year-old man from Deyang in Sichuan province who developed symptoms on March 31 after being exposed to live domestic poultry. He was hospitalized on April 4 and remains in serious condition.
Further details of the cases were not released by the Chinese government, which often takes weeks or months to announce new cases.
The Chinese government revealed last month that a 12-year-old girl and a 79-year-old man died of H5N6 avian flu in December. Both lived in Liuzhou, a city in the Guangxi region, and visited a live poultry market before falling ill.
Only 79 people have been infected with the H5N6 bird flu since the first confirmed case in 2014, but most infections have been diagnosed in the past year. At least 20 cases, including five deaths, have been reported so far this year.
Click here for a list of all human cases to date.
H5N6 bird flu is known to cause serious illness in humans of all ages and has killed nearly half of those infected, including children and young adults. The outcome in most other cases was not disclosed and only 8 people recovered.
There are no confirmed cases of human-to-human transmission, although a woman who tested positive last year denied having contact with live poultry.
“The increasing trend of human infection with the bird flu virus has become an important public health issue that cannot be ignored,” researchers said in a study published by the Chinese Center for Disease Control in September. The study found several mutations in two recent cases of H5N6 avian influenza.
Thijs Kuiken, a professor at the Erasmus University Medical Center in Rotterdam, expressed concern about the growing number of cases. “It could be that this variant is a bit more contagious (to people)…or there could be more of this virus in poultry right now and that’s why more people are getting infected,” Kuiken told Reuters in October.
Earlier that month, the World Health Organization said the risk of human-to-human transmission remains low because H5N6 has not acquired the capacity for sustained human-to-human transmission. However, increased surveillance is “urgently required” to better understand the growing number of human cases, the spokesperson said.