BEIJING: The health experts in Hong Kong have warned of new clinical features including hoarseness and inspiratory stridor (a sign of airway obstruction) among children suffering from COVID-19 during the fifth wave.
The latest development brings concerns for the city, which has reported over 7,000 COVID-19 cases for four consecutive days, as the new school year for primary and secondary schools is set to begin on September 1, as per local media reports.
According to China's Global Times, Chuang Shuk-Kwan, director of the Communicable Diseases Division of the Center for Health Protection of the HKSAR Government's Department of Health said that he found some infected children had developed croup which indicates an inflammation of the larynx, windpipe, and bronchial tubes.
Mike Kwan Yat-wah, the consultant at the department of paediatrics and adolescent medicine at Princess Margaret Hospital, said that the clinical features among children during the fifth wave driven by the Omicron variant differ from those observed in the previous ones.
"Its symptoms are hoarseness and inspiratory stridor. In severe cases it can produce acute obstruction of the respiratory tract and an absence of oxygen supply to an organ or a tissue," he added.
Kwan further said, "This condition can also be caused by various infectious agents, such as parainfluenza virus. However, in the recent COVID pandemic, this condition was nearly all caused by the Omicron variant."
According to Kwan, the possibility of prolonged COVID-19 symptoms, saying about 19 per cent of children who have recovered from COVID-19 present with at least one of these symptoms in the outpatient follow-up at his hospital - Princess Margaret Hospital.
"The most common complaints were memory loss, cognitive deficits, insomnia, headaches, and discomfort," he noted.
Noticeably, there are two confirmed cases in children who have been newly classified as "serious" and are being treated in the children's ICU at Princess Margaret Hospital.
One of them, a 17-month-old boy, had a fever and convulsions on the night of Friday and briefly stopped breathing. He got croup after being infected and just received his first dose of vaccine on that day. Expert advisers to the SAR government believed that the boy's condition was caused by the COVID virus.
Another 10-year-old boy developed a high fever and tested positive on August 22. He sought medical treatment on Thursday for breathing difficulties, Global Times reported.
Infections with Omicron variants are still on the rise with the proportion of new cases infected with BA.4 (or BA.5) in Hong Kong rising to 48.6 per cent, while BA.2.12.1 accounted for 7.6 per cent, according to Chuang Shuk-Kwan.
Chuang predicted that, for the upcoming school season, the proportion of confirmed cases among students and teachers would increase, and that daily tests would be required to prevent transmission on campus.
Hong Kong Chief Executive, John Lee Ka-chiu on Saturday said that current vaccination rates among senior citizens and children were non-ideal and this group of the population reported higher rates of severe illness and death after COVID-19 infection.
"Among them, about 30 per cent of people over 80 years old, 20 per cent of people between 3 and 11 years old and 90 per cent of people under 3 years old have not been vaccinated," he added.
Under current Covid-19 restrictions, schools are allowed to conduct full-day in-person classes if all staff members and 90 per cent of students have received two doses of a Covid-19 vaccine.
However, since the fifth outbreak began in Hong Kong, the city has reported over 7,000 confirmed COVID-19 cases for four consecutive days. The city has seen a steady rise in the number of daily infections since the fifth wave, which peaked in March.
Hong Kong reported 9,708 new Covid-19 cases on Sunday, of which 213 infections were imported. The city also recorded 10 new deaths.
On Saturday, a total of 8,457 new cases were confirmed and four deaths were reported, Chuang Shuk-Kwan told.
In-person learning at Hong Kong schools has been repeatedly interrupted since the Covid-19 pandemic began over two and a half years ago.
The Hong Kong authorities are still mulling over the decision to conduct in-person classes and the city's education chief has said that if the number of daily Covid-19 infections exceeds 10,000, may suspend full-day in-person teaching.