Research and analysis

HPR volume 12 issue 24: news (6 July)

Updated 21 December 2018

New rabies risk assessment and control regime

Public Health England (PHE) has published updated guidelines for health professionals on rabies prevention taking account of new WHO recommendations [1].

The suite of documents – covering pre-exposure prophylaxis, risk assessment and post-exposure treatment – are available via the PHE website guidance collection: Rabies: risk assessment, post-exposure treatment, management.

Key changes to the guidelines include:

• clarification of the employer’s role in providing pre-exposure vaccination to those who may have an increased risk of exposure to rabies through their work
• pre-exposure vaccine will only be provided by PHE for bat handlers, where no formal employer can be identified [2]
• the option of an accelerated course of pre-exposure vaccination is introduced, where there is insufficient time to complete the routine 28-day course of pre-exposure prophylaxis
• a composite rabies risk assessment protocol is introduced for post-exposure treatment, bringing together country and animal risks into a single risk rating, to recognise the increased rabies risk from some animal species in certain countries [3]
• reduction from 5 to 4 doses of vaccine for post-exposure treatment in immunocompetent individuals
• an emphasis on infiltration of human rabies immunoglobulin (HRIG) at the site of the exposure, rather than being given intramuscularly
• changes in the use of HRIG for certain exposures
• new guidance for the management of immunosuppressed individuals.

Post-exposure risk assessment and treatment

The largest group covered by the guidelines are the approximately 2,000 people each year who require post-exposure treatment from PHE following an animal exposure overseas or a bat exposure in the UK. For this group, revised guidelines on managing post-exposure cases include a new 4-step risk assessment process incorporating the country in which the exposure occurred, the animal involved, the category of exposure, and the immune status of the individual [4,5].

A revised version of Chapter 27 of PHE’s ‘Green Book’ Immunisation against infectious disease will be published in due course.

References

1. WHO (April 2018). Rabies vaccines: position paper.
2. PHE website (June 2018). PHE guidelines on requesting rabies pre-exposure prophylaxis.
3. PHE website (2 July 2018). Rabies risks by country.
4. PHE website (2 July 2018). Guidelines on managing rabies post-exposure (June 2018).
5. PHE website (2 July 2018). Rabies post-exposure risk assessment form and calendar.

Outbreak of listeriosis in the European Union (EU): European Centre for Disease Prevention and Control (ECDC) and European Food Safety Authority (EFSA) update

A multi-country outbreak of listeriosis associated with the consumption of frozen sweetcorn – and possibly other frozen vegetables – has been ongoing since 2015 in five EU member states, including the UK, and is the subject of a joint ECDC-EFSA rapid outbreak assessment [1]. As of 3 July, 2018, 47 cases, 9 of whom died, had been reported across the 5 member states [1]. In the UK, since 2015, there have been 11 cases including 2 deaths [2,3].

This outbreak was identified using whole genome sequencing (WGS) analysis of Listeria monocytogenes isolates from cases which enabled the linking of cases over a long time frame and in different countries. Evidence of cases’ exposure to frozen sweetcorn, WGS analysis of L. monocytogenes isolated from food samples, and product trace-back has confirmed a link with frozen sweetcorn produced in Hungary [1]. This illustrates the power and advantages of using WGS over traditional strain typing methods for detecting and investigating foodborne disease outbreaks.

WGS has also confirmed the presence of the outbreak strain in other frozen vegetables at the production site in Hungary and thus other frozen vegetables may possibly be associated with this outbreak. The frozen vegetables (including sweetcorn) implicated are not considered to be ready-to-eat products. Yet evidence exists that (a) some consumers are eating uncooked or inadequately cooked frozen sweetcorn, and (b) caterers may be adding uncooked frozen sweetcorn to ready-to eat-food products such as salads and sandwich fillings [1].

In order to reduce the risk of human infection, the Hungarian Food Chain Safety Office has banned the marketing of all frozen vegetable and frozen mixed vegetable products produced by the Hungarian plant between August 2016 and June 2018, and has ordered the immediate withdrawal and recall of these products: the company is complying. More details about the product recall can be found on the Food Standards Agency (FSA) website [3].

In the UK, the Food Standards Agency, Food Standards Scotland, PHE, and Health Protection Scotland are advising the public to follow manufacturers’ instructions on cooking frozen vegetables before eating them or adding them to salads or any other ready-to-eat foods. This advice applies especially to consumers at the highest risk of contracting listeriosis – such as the elderly, pregnant women, new-borns and adults with weakened immune systems [4].

PHE and Health Protection Scotland, in collaboration with the FSA and Food Standards Scotland, are continuing to investigate the outbreak in the UK and to ensure preventative actions are being taken.

Reference

1. ECDC/EFSA (3 July 2018). Multi-country outbreak of Listeria monocytogenes serogroup IVb, multi-locus sequence type 6, infections probably linked to frozen vegetables: first update.
2. PHE (13 April 2018). Outbreak of listeriosis in the EU: an update, HPR 12(13).
3. Greenyard Frozen UK Ltd recalls various frozen vegetable products due to possible contamination with Listeria monocytogenes, FSA statement (5 July)
4. Listeriosis cases linked to frozen sweetcorn, joint PHE/FSA statement (3 July 2018).

Malaria imported into the UK: 2017

A total of 1,792 cases of imported malaria were reported in the UK in 2017, according to recently published annual data, 10.8% higher than reported in 2016 [1].

Six UK deaths were associated with malaria importations in 2017, the same number as in 2016. These were all from falciparum malaria acquired in Western Africa (3), Eastern Africa (2), and South-Eastern Asia (1). Cases were reported in England (1,708), Scotland (50), Wales (24) and Northern Ireland (10).

Most cases in 2017 were caused by Plasmodium falciparum, which is consistent with previous years. Advice for healthcare workers who advise UK-based travellers is on the PHE website [2]. Country-specific advice for travellers is available on the NaTHNaC website [3].

References

1. PHE website (6 July 2018). Malaria imported into the UK 2017: implications for those advising travellers.
2. PHE website (July 2018). Malaria prevention guidelines for travellers from the UK.
3. NaTHNaC website. Countries A to Z.

Infection reports in this issue

• Laboratory reports of respiratory infections made to PHE from PHE and NHS laboratories in England and Wales: weeks 22 to 26, 2018

• Laboratory surveillance of Klebsiella spp. bacteraemia in England, Wales and Northern Ireland: 2017