Health authorities in Hong Kong on Saturday urged the public to get vaccinated against seasonal influenza as early as possible following a severe pediatric case involving a seven-year-old girl with an underlying medical condition.

The patient, who had no travel history during the incubation period and has not been vaccinated against flu this year, developed a runny nose, diarrhea and abdominal pain on Thursday.

According to the Centre for Health Protection, the girl had a fever and convulsions the following day and was admitted to the accident and emergency department at Tuen Mun Hospital. Her condition subsequently deteriorated and she was transferred to the pediatric intensive care unit.

“Her respiratory specimen tested positive for influenza A (H1) virus. Her clinical diagnosis was influenza A infection complicated with septic shock. The patient is currently in a critical condition,” the center said.

The patient’s household contacts have remained asymptomatic, while three of her classmates have developed mild flu-like symptoms without requiring hospitalization. The CHP advised her school to implement appropriate infection control measures, saying it’ll continue to investigate the case.

ALSO READ: HK residents urged to get flu jab with three more children infected

“Hong Kong entered the influenza season in late June this year and the influenza season has now lasted four months. The latest surveillance data showed that the overall influenza activity showed signs of decline but remained above the baseline level,” CHP Controller Edwin Tsui Lok-kin said.

So far, 28 cases of severe pediatric influenza infection have been recorded in Hong Kong during the current season. They include 20 patients who have recovered and discharged from hospital, while two other remain in stable condition, four in a critical condition and two have died.

The CHP’s analysis of data from the previous year showed that the rate of severe complications or death among unvaccinated children following influenza infection was about five times higher than that among vaccinated children.

Tsui urged all individuals aged six months or above to get vaccinated to prevent severe infection and its complications, and reduce the risk of hospitalization and death.