Similar arrangements should also be given to Hong Kong residents born in mainland China in and before 2002, when free hepatitis B vaccines were offered to all babies.

He said screening could help identify patients with a condition that might not necessarily present symptoms and offer timely intervention.

“All hepatitis B carriers should be followed up by a doctor, who can either be a specialist or a primary care doctor,” Seto said.

“Hepatitis B is a chronic disease … and if it is left untreated, there can be a higher chance of developing cirrhosis and liver cancer.”

Hepatitis B remains a prevalent condition in Hong Kong, in particular among the middle-aged and elderly.

According to a survey report published by the Department of Health in December last year, the prevalence rate among about 2,000 interviewees aged 15 to 84 was 6.2 per cent, suggesting about 465,000 people citywide could be infected with the virus.

While rates ranged from 0.3 per cent to 1.5 per cent for those aged 15 to 34, the number peaked at 8.4 per cent in the 35 to 54 age group, and dropped slightly to 7 per cent for people aged 65 to 84.

But the figures may be underestimating the actual situation locally, as only about 56 per cent of hepatitis B patients have been diagnosed, according to the latest estimate by an international group of epidemiologists.

The World Health Organization has set a global goal of achieving a 90 per cent diagnostic rate by 2030 to eliminate the disease eventually.

A blood test can be done to tell if someone is infected. A rapid finger-prick test is also available, delivering the result in as little as 15 minutes.

Seto said younger patients usually found out they had the infection through body checks, which have been gaining traction locally.

Older people might only find out when they develop serious complications, which are much harder to treat than the early stages, he said.

Hong Kong long way away from hepatitis B elimination goal: health authorities

Candy Wong Ngai-sze, an assistant professor at the Chinese University of Hong Kong’s school of public health, said screening a specific age group might come in useful.

She said a past study of hers from 2018 to 2020 also identified a higher prevalence of hepatitis B among age groups that were not covered by the neonatal vaccination programme.

“With a finite number of the population to be screened, screening a specific age group may be useful for reducing severe morbidity and mortality,” said Wong, who is also conducting the government-commissioned study looking into the cost-effectiveness of hepatitis B screening strategies in Hong Kong.

The study’s findings have yet to be made public.

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Professor Grace Wong Lai-hung of Chinese University’s department of medicine and therapeutics said the government could start by offering free screening to family members of hepatitis B patients, before extending it to other adults.

While family members of infected people were among six groups given priority to be screened, it only meant doctors would remind them to go for a test, she said. No free tests are offered to them.

“Currently there isn’t a formal pathway for people to be automatically enrolled in screening if their family member is a hepatitis B patient. All must be self-initiated,” Wong noted.

The five other groups with priority for testing are people who inject drugs, those with HIV, men who have sex with men, sex workers and prison inmates.

To improve screening access, Wong said the government could harness the 18 citywide district health centres to offer the simple blood test.

“If a person has a referral stating their family members have hepatitis B, they can go to a nearby spot for a free test. This can increase the [testing] uptake rate,” she said, adding that the approach would be easier than offering the test in a hospital setting.

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While as many as 70 per cent of hepatitis B patients surveyed in the Department of Health report did not have the condition monitored regularly by medical professionals, both Seto and Wong pointed to the importance of medical follow-ups even though the infection could be symptom-free for 20 to 30 years.

Patients can undergo regular blood checks and ultrasounds to monitor their livers, and receive antiviral treatments if necessary.

“If we can prescribe medications on time, the chance of complications can be greatly reduced, and so screening is seen as a way to prevent complications,” Wong said.

The department said the steering committee on prevention and control of viral hepatitis would consider local and international developments when advising the government on strategies related to control of the infection.

The study being done by Chinese University would also help inform priorities of resources for hepatitis B screening and formulate the next action plan, it said.