Research and analysis

HPR volume 11 issue 26: news (28 July)

Updated 15 December 2017

1. Hepatitis C in the UK annual report

Mortality attributable to hepatitis C-related end-stage liver disease and liver cancer continues to fall in the UK, reversing the trend seen in the decade prior to 2015. Latest data suggest deaths in the UK fell by 3% between 2014 and 2015, with provisional data for 2016 suggesting a further fall in deaths of 7% over the last year in England, Wales and Scotland.

However, there is no evidence of any similar reduction in numbers of new HCV infections recorded in recent years. People who inject drugs (PWID) are the principal risk group for HCV and both estimated rates of infection and the prevalence of infection in recent initiates to drug use in 2016 were similar to those observed in 2011 and 2008, respectively. Therefore, the World Health Organization GHSS targets of a 30% reduction in new cases of chronic HCV by 2020 – and of 80% by 2030 – are significant challenges for UK health services.

These are key conclusions of Public Health England’s ninth annual Hepatitis C in the UK report [1], published to coincide with World Hepatitis Day, 28 July [2,3,4].

The downward trend in mortality – observed since 2014 – is likely to be the result of increased treatment with new direct acting antiviral (DAA) drugs; HCV treatment increased by 46% between 2015 to 2016 and 2016 to 2017. The increasing availability of this medication means the UK is well-placed to meet the WHO GHSS targets to reduce HCV-related mortality by 10% by 2020, and by 65% by 2030, according to the PHE report.

Sustaining this increase in treatment will ultimately be limited by public health service capacity to find and treat those who remain undiagnosed and to help those who are diagnosed but untreated to engage with local treatment services. UK surveys of PWID suggest that only around one half are aware of their HCV antibody positive status, a figure that has remained relatively stable at this level for several years. The new PHE report states that, ‘Although the WHO target of 50% of infected people in the WHO European region knowing their status by 2020 may have already been met in the UK, more work is needed if we are to meet the target of 90% diagnosed by 2030’.

1.1 References

1. PHE (28 July). Hepatitis C in the UK annual report.
2. PHE website. ‘Public Health England encourages hepatitis C testing’ (news story).
3. UK campaign website. worldhepatitisday.org/en/about-us.
4. ECDC (26 July). ECDC: around nine million Europeans are affected by chronic hepatitis B or C

2. Transfusion transmitted infections (UK): 2016

During 2016, UK Blood Services investigated 108 incidents of suspected bacterial transmission and 18 incidents of suspected viral transmission among transfusion recipients. These investigations concluded that only one incident was due to transfusion transmission of HEV, that patient having received multiple transfusions between October 2015 and January 2016.

Two viral investigations are pending. A further 4 incidents were considered to be bacterial ‘near miss’ events (3 from Northern Ireland and 1 from England). The packs involved in near-miss events in 2016 were seen to be visibly abnormal and investigated, bacteria subsequently being cultured from the platelet donations; as a result, none of these units were transfused.

Details of the suspected transfusion-transmitted infection (TTI) incidents investigated by the UK Blood Services in 2016 have been published in the Serious Hazards of Transfusion (SHOT) Annual Report [1].

Important messages from the report are that:

• bacterial screening of platelets will reduce but not remove the risk of transfusion transmission of bacteria
• bedside vigilance and close inspection of transfusion packs prior to the transfusion is essential to avoid TTIs from occurring, the 3 near-miss incidents mentioned above were prevented from being TTIs due to the thorough visual inspection carried out by hospital staff
• the risk of a screened component transmitting hepatitis B virus (HBV), hepatitis C virus (HCV) or human immunodeficiency virus (HIV) in the UK is very low [2]. Nevertheless, to maintain haemovigilance, investigations are performed if a recipient is suspected to have been infected via transfusion.

Following a review by the Advisory Committee on the Safety of Blood, Tissues and Organs (SaBTO 2016) in October 2016, UK Blood Services have implemented 100% HEV-screening. As a result, 100% HEV-screened red cells were available from 1 May 2017 in England, from 3 April in Wales, and from 5 April in Scotland. Replacement of frozen components followed as stocks were used up.

Suspected transfusion-transmitted infections should be reported to the blood services who can advise on the information required and how to proceed. Further information about how and what to report can be found in SHOT Bites no. 7 Transfusion transmitted infections.

Further information about UK TTI surveillance is available from the joint NHSBT/PHE Epidemiology Unit (located in the Immunisation, Hepatitis and Blood Safety Department): [email protected].

2.1 References

1. PHB Bolton-Maggs (ed), D Poles et al (on behalf of the Serious Hazards of Transfusion (SHOT) Steering Group) (2017) The 2016 Annual SHOT report.
2. PHE (2015). Safe Supplies: Reflecting on the Population. Annual Review from the NHS Blood and Transplant / Public Health England Epidemiology Unit.

3. HIV and viral hepatitis monitoring among PWID

The latest data tables for the Unlinked Anonymous Monitoring (UAM) Survey of People Who Inject Drugs (PWID) have been published by PHE [1] and a full commentary article on the data is included in the infection reports section of this issue of Health Protection Report [2].

The survey measures the prevalence of antibodies to HIV, hepatitis C and hepatitis B – as well as levels of risk and protective behaviours – in the PWID population. The data released is from the 2016 survey of people who injected psychoactive drugs, such as heroin and crack. This annual survey covers England, Wales and Northern Ireland, and data is presented at country level and for the English regions.

Overall, the data from the UAM Survey show that infections remain a problem among people who inject drugs. The data indicate that HIV prevalence remains stable among PWID at 0.85%. The vast majority of those with HIV were aware of their HIV infection. The survey found that 14% of survey respondents had ever been infected with hepatitis B (antibodies to the hepatitis B core antigen) and 0.43% had current hepatitis B infection (HBsAg). However, hepatitis C remains the most common infection among this group with 53% having antibodies to hepatitis C. About half (52%) were aware of their hepatitis C infection.

Overall, 17% of those currently injecting had shared needles and syringes during preceding the 28 days, and injecting drugs into higher risk sites on the body, such as the groin and hands, was also common. Although uptake of diagnostic testing for HIV and hepatitis C – and of the hepatitis B vaccine – are all high, the uptake of these interventions has not increased in recent years and uptake of hepatitis B vaccination appears to be declining in younger age groups.

Over one-third of those who injected during the preceding year reported having a swelling containing pus (abscess), sore or open wound at an injection site. Injection of crack has increased in the last decade in Wales and in multiple regions in England.

The HPR commentary concludes that interventions which aim to prevent infection through injecting drug use, including needle and syringe programmes and opioid substitution therapy [2], need to be sustained.

3.1 References

1. PHE (28 July). People who inject drugs: HIV and viral hepatitis unlinked anonymous monitoring survey tables (psychoactive): 2017 update.
2. PHE (28 July). Unlinked anonymous HIV and viral hepatitis monitoring among PWID: 2017 report.

4. Cyclospora outbreak related to travel to Mexico (2017)

During the summers of 2015 and 2016, the UK saw two outbreaks of Cyclospora infection in travellers who had been to Mexico [1,2]. For a third summer in a row, an increase in cases of Cyclospora infection has been reported in the UK in 2017.

As of 27 July, 78 cases have been reported in the UK in 2017, of which 37 (47% of the total) have travelled to Mexico. Investigations are ongoing; travel history is awaited for 20 cases, 14 cases reported travel to nine other overseas destinations and seven reported no overseas travel.

Of the cases that travelled to Mexico, 21 are female and 16 male; the median age group is 40-44 years. Onset dates are known for 27 cases and range between 21/05/2017 and 14/07/2017, with most reporting onset in June and July.

A number of actions have already been taken by the incident management team in the UK:

• advice for travellers has been reviewed and updated on the NaTHNaC website and the Scottish FitforTravel and Travax websites,
• ABTA, the Travel Association, has raised awareness of the 2017 outbreak with its members and circulated the NaTHNaC travel advice, and
• a reminder about testing for Cyclospora has been communicated to local laboratories.

In 2017, cases in travellers returning from Mexico have also been reported by Belgium and France [3]. In addition, outbreaks of cyclosporiasis have been reported in Canada and the United States of America in 2017 although it is not yet clear whether any travel-associated cases have been reported [4,5]. A large outbreak reported in the state of Guanajuato, Mexico is also being investigated by the Health Ministry of the State of Guanajuato and the Mexican surveillance system [3].

The Mexican health authorities have taken a number of actions and are working with the US Food and Drugs Administration to ensure foods previously associated with outbreaks of cyclosporiasis in the US are free from Cyclospora and this is ongoing [6]. The UK will continue to communicate with Mexico regarding investigations related to the current outbreak in travellers.

Travellers who plan to visit Mexico should be aware of the risk of Cyclospora and follow recommended guidance for prevention [7]. Health advice for travellers to Mexico, including advice on food and water hygiene, can be found on the NaTHNaC website.

Cyclospora cayetanensis is a coccidian protozoan parasite that only infects humans; the organism and associated illness has been previously described [8].

There may be substantial under-ascertainment and reporting of cyclosporiasis cases, because not all patients are tested for Cyclospora and not all positives are reported by some laboratories. In addition, these organisms can be difficult to spot and recognise in unstained wet films or concentrates. Faecal samples can be examined using a wet preparation and concentration technique. Any structures resembling Cyclospora are further examined under UV light for parasite autofluorescence or confirmed using modified Ziehl-Neelsen stain and accurate measurement [9].

In view of the ongoing outbreak, PHE recommends that Cyclospora is considered as a possible cause of gastrointestinal infection in patients returning from Mexico. Cases should be reported to the local health protection team (or equivalent). Positive samples should be referred to the appropriate reference laboratory: National Parasitology Reference Laboratory, Hospital for Tropical Diseases in London (England), the Scottish Parasite Diagnostic and Reference Laboratory in Glasgow (Scotland) or the Cryptosporidium Reference Unit in Swansea (Wales) for confirmation.

Travellers who experience symptoms listed above, particularly after overseas travel, should seek medical advice and remember to report any travel history to their healthcare provider.

Further information about Cyclospora is available on the PHE website.

4.1 References

1. PHE (2016). Cyclospora outbreak related to travel to Mexico: an update, HPR 10(26).
2. Nichols GL, Freedman J, Pollock KG, Rumble C, Chalmers RM, Chiodini P, et al (2015). Cyclospora infection linked to travel to Mexico, June to September 2015, Euro Surveill. 20(43).
3. ECDC (21 July 2017). Rapid Risk Assessment: Cyclospora infections in European travellers returning from Mexico.
4. Texas Department of State Health Service (17 July 2017). Cyclospora Health Advisory.
5. Public Health Agency of Canada (14 July 2017). Public Health Notice – Outbreak of Cyclospora infections under investigation (updated).
6. United States Food and Drug Administration (10 July 2017). Import Alert 24-23.
7. PHE website (2016). Cyclospora: advice for travellers (12 August).
8. PHE (2016). Cyclospora outbreak related to travel to Mexico, HPR 10(25).
9. PHE SMI B31. UK Standards for Microbiology Investigations: Investigation of specimens other than blood for parasites

5. Infection reports in this issue of HPR

The following infection reports are published in this issue of HPR. The links below are to the relevant webpage collections or publications.

• Unlinked anonymous HIV and viral hepatitis monitoring among PWID: 2017 report
• Laboratory reports of hepatitis C (E&W): annual report 2016
• Sentinel surveillance study of blood borne virus testing in England: annual report 2016