Chapter 1 hepatitis B virions Blood-borne Viruses Chapter overview The blood-borne viruses summarised in this chapter are hepatitis B, hepatitis C, and hepatitis D. HIV is covered in the sexually transmissible infections chapter. Hepatitis B in Queensland is classified as either acute or unspecified, based on laboratory test results. Population health units generally follow up acute notifications only. Between 22 and 26, there were more than four thousand notifications of hepatitis B, with 6% of these classified as acute hepatitis B. Most unspecified notifications are likely to represent chronic infections. From 22 to 26, all notifications of hepatitis C were classified as unspecified. Population health unit follow-up is not performed routinely for these notifications, unless advised that the notification represents an acute case of illness. In 27, Queensland Health began collecting enhanced surveillance data for a subset of new hepatitis C notifications. This information includes type of hepatitis C (ie. acute or chronic) and risk factors for acquisition. The following observations are noteworthy: The acute hepatitis B notification rate in Queensland in 26 was the lowest recorded since 1997. Unspecified hepatitis B notification rates increased over the 22 26 period. Over the 22 26 period, hepatitis B and C notification rates in Indigenous people were more than double the rates in people of non-indigenous/unknown status. Figure 1.1 Notifications of acute and unspecified hepatitis B, Queensland *, 22 26 12 1 8 Notifications 6 4 2 22 23 24 25 26 Year Acute Unspecified * No notifications were received from SAHS. Notifiable Diseases Report 22-26 1
Hepatitis B (acute) Statistics at a glance (22 26 hepatitis B acute) Average number of notifications per year 52 Queensland rate compared to Australian rate Is any trend in rate of disease apparent (22 26)? Predominant age group 32% lower No trend 2 39 years Percent of all notifications in predominant age group 55% Percent male 63% Differences between area health service rates Health service districts with highest rates No major differences Torres/NPA^ Percent with information on Indigenous status 64% Indigenous people as a percent of all notifications 11% ^ Torres Strait and Northern Peninsula Area. Epidemiology: key points The acute hepatitis B notification rate in Queensland in 26 was the lowest recorded since 1997. Notified cases of acute hepatitis B were more commonly male (male-to-female ratio of 1.7:1); 77% of notified cases aged 3 years and older were male. The highest age-specific acute hepatitis B notification rate was in the 2 29 years age group. Over the 22 26 period, the acute hepatitis B notification rate in Indigenous people was 2.8 times higher than the rate in people of non-indigenous/unknown status. Summary of notifications There were 26 notifications of acute hepatitis B between 22 and 26, ranging from 41 in 23 to 62 in 25. Acute notifications accounted for only 6% of all notifications for hepatitis B, with the remaining 94% of the 4,335 notifications in the five year period classified as unspecified hepatitis B. Notification rates of acute hepatitis B in Queensland were lower than Australian rates from 1997 to 23, but similar from 24 to 26. All three Queensland area health services had similar rates in 26 (Figure 1.2). Torres and Northern Peninsula Area Health Service District (HSD) had a noticeably higher acute hepatitis B notification rate (average annual rate 9.6 per 1, for the 22 26 period) compared to other HSDs. 2 Notifiable Diseases Report 22-26 Background image: hepatitis B virions
hepatitis B virions Figure 1.2 Acute hepatitis B notification rates: Queensland and Australia 1997 26, and Queensland area health services 22 26 3. 2.5 Rate per 1, 2. 1.5 1..5 1997 1998 1999 2 21 22 23 24 25 26 Year Queensland QLD-NAHS QLD-CAHS QLD-SAHS Australia Age and sex Sixty-three percent of acute hepatitis B notifications between 22 and 26 were in men. However, the proportion of notifications occurring in women increased each year, from 31.5% in 22 to 42.% in 26. The age and sex distribution of notified acute hepatitis B cases was similar to that seen in sexually transmissible infections such as chlamydia or gonorrhoea. The largest number of notifications in females was in the 2 29 years age group, followed by the 1 19 and 3 39 years age groups (Figure 1.3). The largest number of notifications in males were in the 3 39 years age group, followed by the 2 29 years age group. Numbers of notifications were at least three times higher in males than females for all age groups 4 years and over, with the male-to-female ratio in the oldest age group (6+) being greater than 8:1. Seventy-seven percent of all notified cases in people aged 3 years and older were male. Notifiable Diseases Report 22-26 3
Figure 1.3 Acute hepatitis B notifications by age group and sex, and average annual age-specific notification rates, Queensland, 22 26 5 3.5 Notifications 45 4 35 3 25 2 15 1 5 3. 2.5 2. 1.5 1..5 Rate per 1, -9 1-19 2-29 3-39 4-49 5-59 6+ Age group (years) Female Male Rate Indigenous status Indigenous status was incomplete for 46% of notifications between 22 and 26 (4% in 26). Eleven percent of notified cases were recorded as being Indigenous. Although likely to be an underestimate due to the high level of missing data, the acute hepatitis B notification rate in Indigenous people was 2.8 times higher than that in people of non-indigenous/unknown status (3.4 and 1.2 per 1, respectively). Vaccination status From 22 to 26, vaccination status was known for 49 of 26 notified cases of acute hepatitis B (19%). Of these, 1 were vaccinated and 39 were unvaccinated. Vaccinated cases were aged between 1 and 32 years (median age of 15 years), and seven were Indigenous. 4 Notifiable Diseases Report 22-26 Background image: hepatitis B virions
hepatitis B virions Hepatitis B (unspecified) Statistics at a glance (26 hepatitis B unspecified) Number of notifications in 26 999 Queensland rate compared to Australian rate Is any trend in rate of disease apparent (22 26)? Predominant age group Similar Increasing 2 39 years Percent of all notifications in predominant age group 56% Percent male 52% Differences between area health service rates Health service districts with highest rates Compared to SAHS, CAHS 5% lower and NAHS 29% lower Torres/NPA^ Percent with information on Indigenous status 35% Indigenous people as a percent of all notifications 5% ^ Torres Strait and Northern Peninsula Area. Epidemiology: key points Notifications of hepatitis B (unspecified) increased between 22 and 26. The Central Area Health Service notification rate of hepatitis B (unspecified) was consistently half that of the other AHSs. Over the 22 to 26 period, notification rates in Indigenous people were more than twice those in people of non-indigenous/unknown status. Summary of notifications Notification rates of hepatitis B (unspecified) decreased in Australia from around 4 per 1, in 1997, to 3 per 1, in 26. Queensland rates, while consistently lower than Australian rates, increased by 3% between 22 and 26, largely due to increased rates in the Southern AHS (Figure 1.4). In 26, nearly 1, cases of hepatitis B (unspecified) were notified in Queensland. While acute hepatitis B notification rates were broadly similar across area health services, hepatitis B (unspecified) notification rates were approximately two times higher in the SAHS and the NAHS compared to the CAHS (average annual rates of 23.5, 26.2 and 12.8 per 1, respectively for the 22 26 period). The HSDs with the highest hepatitis B (unspecified) notification rates for the 22 26 period were: Torres and Northern Peninsula Area, Brisbane South, Cape York, Tablelands and Cairns. Notifiable Diseases Report 22-26 5
Figure 1.4 Hepatitis B (unspecified) notification rates: Queensland and Australia 1997 26, and Queensland area health services 22 26 5 45 4 Rate per 1, 35 3 25 2 15 1 5 1997 1998 1999 2 21 22 23 24 25 26 Year Queensland QLD-NAHS QLD-CAHS QLD-SAHS Australia Age and sex No obvious changes in the age distribution of notifications of hepatitis B (unspecified) were observed between 22 and 26. The highest age-specific notification rates in 26 were in the 2 to 29 years and 3 to 39 years age groups (54 and 43 per 1, respectively) (Figure 1.5). Notified cases of hepatitis B (unspecified) in 26 were evenly distributed by sex (male-to-female ratio of 1.1:1). Female cases were generally younger, with median ages for females and males of 31.5 and 37. years respectively in 26. Figure 1.5 Hepatitis B (unspecified) notifications by age group and sex, and age-specific notification rates, Queensland, 26 Notifications 2 18 16 14 12 1 8 6 4 2-9 1-19 2-29 3-39 4-49 5-59 6+ Age group (years) 6 5 4 3 2 1 Rate per 1, Female Male Rate 6 Notifiable Diseases Report 22-26 Background image: hepatitis B virions
hepatitis B virions Indigenous status Over the 22 26 period, 8% of notifications of hepatitis B (unspecified) were recorded as being in Indigenous people. The average annual Indigenous notification rate (41 per 1,) was twice that of people of non-indigenous/unknown status (2 per 1,). This is likely to be an underestimate, as Indigenous status was unknown for 7% of notifications. While no improvement in collection of Indigenous status was seen over the 22 26 period, completeness of this data field was higher than for the period 1997 21, in which Indigenous status was unknown for 96% of hepatitis B (unspecified) notifications. 1 Vaccination status was unknown for 99.9% of hepatitis B (unspecified) notifications. Hepatitis B in children notifications and immunisation The Australian hepatitis B infant immunisation program started in 1988 for at-risk children. In 2, universal infant immunisation was introduced commencing at birth. Routine screening of pregnant women is conducted, and babies of hepatitis B positive mothers are given hepatitis B immunoglobulin to prevent perinatal transmission. Between 22 and 26, there were 32 cases of hepatitis B in children aged less than 1 years. Two were classified as acute and 3 as unspecified. Seventeen (53%) were male. There were three cases in 22, followed by four, seven, nine and nine cases in the subsequent years. The two acute hepatitis B cases notified in children aged less than 1 years between 22 and 26 were both in the five to nine years age group. One was a non-indigenous child who was unvaccinated, and the other was a child born in Africa whose vaccination status was unknown. Of the thirty hepatitis B (unspecified) cases notified in children aged less than 1 years between 22 and 26, five were in infants aged less than one year. Vaccination status was known for three of these cases, all of whom were unvaccinated. Notifiable Diseases Report 22-26 7
Hepatitis C Statistics at a glance (26 hepatitis C) Number of notifications in 26 2,862 Queensland rate compared to Australian rate Is any trend in rate of disease apparent (22 26)? Predominant age group 16% higher No trend 2 49 years Percent of all notifications in predominant age group 83% Percent male 62% Differences between area health service rates Health service districts with highest rates Compared to SAHS, CAHS 2% lower and NAHS 12% lower West Moreton Percent with information on Indigenous status 35% Indigenous people as a percent of all notifications 5% Epidemiology: key points All notifications of hepatitis C in Queensland over the 22 26 period were classified as unspecified, ie. acute or chronic status not determined. In most age groups, more than 6% of notified cases were male, however in the 15 19 years age group more cases were female. The hepatitis C notification rate in Indigenous people was 1.5 times higher than the rate in people of non-indigenous/unknown status. Summary of notifications Over the period 1997 to 26, there was a decreasing trend in hepatitis C notification rates most notably at the national level (Figure 1.6). This could be due to changes in reporting practices. In Queensland, rates were fairly steady from 22 to 26. In 26, the Queensland notification rate of 69.9 per 1, was 16% higher than the national rate (6.4 per 1,). Within Queensland, the CAHS notification rate was consistently lower than the state rate, and the SAHS rate consistently higher. 8 Notifiable Diseases Report 22-26 Background image: hepatitis B virions
hepatitis B virions Figure 1.6 Hepatitis C notification rates: Queensland, Queensland area health services, and Australia, 1997 26 13 12 11 Rate per 1, 1 9 8 7 6 5 4 1997 1998 1999 2 21 22 23 24 25 26 Year Queensland QLD-NAHS QLD-CAHS QLD-SAHS Australia Age and sex The highest age-specific notification rates for hepatitis C in 26 were in the age groups from 2 to 49 years (Figure 1.7). More males than females were notified in all age groups, except in teenagers between 15 and 19 years of age. The overall male-to-female ratio was 1.7:1. Fifty of the 84 notified cases in 15 to 19 year olds (6%) were female (Figure 1.7). Figure 1.7 6 5 Hepatitis C notifications by age group and sex,and age-specific notification rates, Queensland, 26 16 14 Notifications 4 3 2 1 12 1 8 6 4 2 Rate per 1, <15 15-19 2-29 3-39 4-49 5-59 6+ Age group (years) Female Male Rate Notifiable Diseases Report 22-26 9
Between 22 and 26, 63% of notified cases of hepatitis C were male. The male-to-female ratio (1.7:1) did not change over this period. However in 15 19 year olds, more notified cases were female (53% of 518 notifications). This could be due to different testing practices and/or risk behaviour in teenage girls compared to teenage boys. The number of notifications in people aged 15 19 years decreased from 157 in 22 to 84 in 26 (Figure 1.8). At the same time, notifications in people aged 5 64 years increased from 169 in 22 to 345 in 26. More than 7% of notified cases in people aged 5 years and older were male, with a male-to-female ratio of 2.1:1. Figure 1.8 Trends in notifications of hepatitis C for selected age groups, Queensland, 22 26 4 35 Notifications 3 25 2 15 1 5 22 23 24 25 26 Year -14 15-19 5-64 65+ Indigenous status Of the notified hepatitis C cases over the 22 26 period, 5.5% were recorded as being Indigenous. This is likely to be an underestimate of the true percent Indigenous, as Indigenous status was unknown for 62% of notifications over this period. Completeness of this data field did not improve between 22 and 26. Co-infection with hepatitis B Of the 2,862 people notified with hepatitis C in 26, 49 were known to be co-infected with hepatitis B, as evidenced by a notification on NOCS. Nine of these had a prior notification of hepatitis B (unspecified), and 4 had a concurrent notification of either unspecified or acute hepatitis B. Morbidity and mortality Hepatitis C is a common cause of liver failure. Hospital and death certificate data are considered to be gross underestimates of the true burden of hepatitis C on the health care system. Nonetheless, hepatitis C (ICD-1 AM codes B17.1 or B18.2) was cited as the main cause of death for 35 deaths registered in Queensland between 21 and 25, and as the principal diagnosis in 2,185 hospitalisations between 22 and 26 (an average of 437 annually). Sixty-seven percent of these hospitalisations were male. 1 Notifiable Diseases Report 22-26 Background image: hepatitis B virions
hepatitis B virions Public health implications and risk factors (hepatitis B and C) Hepatitis B and C are common causes of liver disease requiring liver transplant, and of hepatocellular carcinoma. In 26, 28% of liver transplants listed hepatitis B or C as the primary cause of liver disease, according to data from the Australia and New Zealand Liver Transplant Registry. 2 Hepatitis B is thought to be responsible for up to 8% of all cases of hepatocellular carcinoma worldwide. 3 The Australia and New Zealand registry records 8% of cases of hepatocellular carcinoma occurring in 26 as positive for hepatitis B or C. 2 The seroprevalence of hepatitis B and hepatitis C amongst Queensland blood donors in 26 was 11 per 1, and 8.6 per 1, respectively. 2 Hepatitis C seroprevalence decreased steadily from 23.4 per 1, donors in 22 to 8.6 per 1, donors in 26. Blood donors are a highly selected population of healthy individuals, and changes in seroprevalence may reflect changes in screening practices. No trend in hepatitis B seroprevalence was observed over the same period. 2 Hepatitis C seroprevalence is much higher in certain high risk populations. Fifty-six percent of intravenous drug users tested at needle and syringe programs in Queensland in 26 were hepatitis C antibody positive, compared to the Australia-wide figure of 61%. No trend in seroprevalence in this high risk group was observed for the period 22 to 26. Injecting drug use continues to be the most common risk factor for hepatitis B and C in Australia. 2 The last quarter of 26 marked the first time risk factor information was collected in Queensland on people treated in liver clinics and diagnosed with hepatitis C. Data was collected on 386 people treated at a public liver clinic between October and December 26. The results show that injecting drug use was the most commonly stated risk factor, with 72% reporting they had ever injected drugs, and 68% reporting injecting drugs within the last two years. Other commonly reported risk factors for hepatitis C included receiving tattoos (27%) and transplant or transfusion (11%). 4 In 27, this information was further characterised by hepatitis C status (incident or chronic). The identification of newly acquired hepatitis C is a challenge because a prior negative test for hepatitis C is required. While universal infant immunisation is an effective intervention against hepatitis B, it is not expected to result in a decrease in disease rates until 15 years after program commencement. 3 Reductions should be apparent in the youngest age groups first. To accurately report on this expected decrease, complete information on vaccination status will be required for children notified with acute hepatitis B. Increases in migration of young children from endemic areas may reduce the ability to observe vaccination program effects. Important considerations in the interpretation of hepatitis B and C notification rates are the effect of mass screening programs. These occur from time to time in the general population in the NAHS, and also amongst newly arrived refugee groups statewide. The originating countries of refugee populations often have higher endemic rates of hepatitis B and C than Australia. Notifiable Diseases Report 22-26 11
Hepatitis D Hepatitis D virus causes illness only in people infected with hepatitis B. 3 Over the period 22 26, there were 34 notifications of hepatitis D. Seventy-nine percent of notified cases were male. None were reported as being Indigenous: 23 were non-indigenous (68%), with the remaining cases of unknown Indigenous status. Notifications were predominantly from the SAHS (62%), with 32% from the CAHS and 6% from the NAHS. However in 26, four of the eight notifications were from the CAHS. The majority of the cases were notified between 24 and 26 (12, 11 and eight cases respectively). Notified cases of hepatitis D over the 22 26 period ranged in age from 17 to 64 years, with mean and median ages of 41 and 45 respectively. Fifty percent of cases were in the 4 49 years age group. Two cases were in the 15 19 years age group; all other cases were 2 years or older. Table 1.1 Hepatitis D notification rates per 1, population, Queensland and Australia, 22 26 22 23 24 25 26 22 26 * Queensland.5.3.31.28.2.17 Australia.11.14.14.15.15.14 * The 22 26 rate is the average annual rate per 1, population. 12 Notifiable Diseases Report 22-26 Background image: hepatitis B virions
hepatitis B virions Queensland s hepatitis control strategy, programs and research initiatives The Queensland hepatitis C program is underpinned by a whole-of-government strategy which seeks to reduce the transmission of hepatitis C, minimise the impact of hepatitis C on the Queensland population, and improve the health and well-being of people living with hepatitis C. The Queensland HIV, Hepatitis C and Sexually Transmissible Infections Strategy 25 211 expands on the success of existing programs and services, including strengthening the partnership with various sectors (such as non-government and primary health care) to achieve the desired outcomes outlined in the strategy. Currently in Queensland, it is not possible to distinguish acute and chronic hepatitis C infections from routinely collected surveillance data. This limits the ability of this data to inform public health interventions. Collecting more detailed information on newly diagnosed infections, particularly among high risk populations, and improving the reporting of ethnicity and Indigenous status for people diagnosed with hepatitis B and/or hepatitis C remain key challenges for the Queensland program. Queensland Health is seeking to improve knowledge and information on hepatitis C through participation in a number of research and surveillance initiatives. Strategies include supporting other key stakeholders (eg. Queensland Corrective Services) where appropriate. Current Queensland activities include: Support for research to establish a sentinel surveillance network in Queensland. This project will examine the potential role of a range of service providers in enhancing hepatitis C surveillance activity in Queensland. Service providers involved will include general practitioners, population health units, sexual health services, mental health facilities, alcohol and drug treatment services, needle and syringe programs, pathology services, public hospitals, correctional facilities, community-controlled medical services, migrant and refugee health services, and community-based organisations. Continued improvement in routine data collection for high risk populations through participation in the annual Australian Needle and Syringe Program Survey and the National Blood-borne Virus Prison Entrants Survey. Both surveys provide in-depth information on risk-taking behaviours amongst populations at increased risk of transmission of hepatitis B and C (ie. injecting drug users and prisoners). Participation in national research such as the Gay Periodic Survey also provides information regarding trends over time for other at-risk populations. Notifiable Diseases Report 22-26 13
Queensland Health is also collecting enhanced surveillance data through initiatives such as the Hepatitis C Shared Care Initiative in ten public hospitals across Queensland. Treatment via a public hospital liver clinic currently requires a person with hepatitis C to complete six to 12 months of therapy, with monitoring of treatment outcomes at routine intervals. The process includes regular assessment of pathology results, monitoring of treatment side effects and counselling support. The Shared Care model increases the level of involvement of the general practitioner and relevant allied health professionals in the management of a person with hepatitis C, including general health monitoring, assessment for treatment, management of treatment (including compliance) and management following completion of drug treatment. Data collected through the initiative will provide information regarding the following: risk factors for transmission; ethnicity and Indigenous status of those seeking treatment; waiting times; treatment uptake and response; and patterns of referral. Such information will assist in determining the effectiveness of the model of care and any changes to the model into the future. A tripling of the number of people on treatment is required to make any impact on the long-term demands and costs of hepatitis C infection on the health care system. Australian Chronic Hepatitis C Observational Study (ACHOS) ACHOS provides the opportunity for Queensland to participate in a national study with potential to provide more detailed information regarding hepatitis C treatment uptake rates and predictors, treatment response rates, and the impact of treatment on long-term morbidity. The study will also provide the opportunity to compare clinic-based treatment outcomes to clinical trial outcomes, and allow more realistic input data for hepatitis C treatment models in Australia. The observational database will also provide the opportunity to monitor the impact of ethnicity, country of birth, and Indigenous status on treatment uptake, treatment outcomes, and morbidity. Anecdotal information suggests low rates of treatment among Indigenous Australians. This is exacerbated by the absence of ethnicity and Indigenous status recording in most hepatitis C surveillance systems in Australia. Queensland Health will continue to investigate strategies to improve knowledge and understanding of the impact of viral hepatitis on the Queensland population, the health system and the individuals affected. 14 Notifiable Diseases Report 22-26 Background image: hepatitis B virions
hepatitis B virions Figure 1.9 Average annual hepatitis C notification rates by health service district, Queensland, 22 26 Notification rate, 22 to 26 per 1, population Banana 21 to 25 Bundaberg 11 to 15 51 to 1 to 5 Torres North Burnett Fraser Coast Gympie Cape York Cairns Northern Downs Southern Downs South Burnett Toowoomba West Moreton Sunshine Coast Redcliffe- Caboolture Logan/ Beaudesert Brisbane North Bayside Brisbane South Gold Coast Inset Tablelands Innisfail Townsville Mt Isa Charters Towers Bowen Mackay Moranbah Rockhampton Central West Central Highlands Gladstone Charleville Roma See inset No notification rates between 151 and 2 per 1, population. Notifiable Diseases Report 22-26 15
Photo credits Centers for Disease Control and Prevention. Public Health Image Library electron micrograph of hepatitis-b virus HBV Dane particles or virions. ID no. 5631. [Online]. n.d. [last accessed 6 Apr 29]. Available from: URL:http://phil.cdc.gov. Centers for Disease Control and Prevention. Public Health Image Library electron micrograph of hepatitis-b virus HBV Dane particles or virions. ID no. 27. [Online]. n.d. [last accessed 6 Apr 29]. Available from: URL:http://phil.cdc.gov. References 1. Pugh R. Queensland Health notifiable diseases report 1997 21. Brisbane: Queensland Health, 22. 2. Heymann DL, ed. Control of communicable diseases manual. 18th edn. Washington, DC: American Public Health Association, 24. 3. National Centre in HIV Epidemiology and Clinical Research, ed. HIV/AIDS, viral hepatitis and sexually transmissible infections in Australia annual surveillance report 27. Cat. no. PHE 92. Canberra: Australian Institute of Health and Welfare, 27. 4. Queensland Health Communicable Diseases Branch (HIV/AIDS, Hepatitis C and Sexual Health area). Unpublished data. Brisbane: Queensland Health, 27. 16 Notifiable Diseases Report 22-26 Background image: hepatitis B virions