Dilys Morgan

Indigenous Hepatitis E in England and Wales From 2003 to 2012: Evidence of an Emerging Novel Phylotype of Viruses

BACKGROUND Enhanced surveillance and molecular characterisation studies of hepatitis E virus (HEV) in England and Wales have been undertaken since 2003. The dynamics of hepatitis E have changed recently with an increase in the number of indigenous cases and an observed viral shift. METHODS HEV antibody and RNA data were analysed to ascertain the annual number of acute infections, the HEV genotype disposition and viral phylogeny. These data were investigated in the context of collected travel history and demographic data. RESULTS In total, 2713 acute hepatitis E cases were diagnosed, of which 1376 were indigenous infections. Travel associated cases remained steady and mainly associated with Genotype 1 infections. In contrast, major fluctuations were noted in indigenously-acquired cases with a dramatic year on year increase during 2010-2012. Molecular characterisation demonstrated indigenous infections to cluster into two distinct phylogenetic groups with the emergence of a novel group of Genotype 3 viruses coinciding with the recent increase in cases. CONCLUSIONS HEV infection rates are dynamic in England and Wales, influenced by changing trends in indigenously-acquired cases. The recent increase in indigenous cases and the emergence of indigenous viruses not commonly circulating prior to 2010 suggest that the risk of acquiring HEV has changed.

Hepatitis E virus in England and Wales: indigenous infection is associated with the consumption of processed pork products

Indigenously acquired hepatitis E infections have increased substantially in England and Wales since 2010. Epidemiological investigations were undertaken to determine risk factors for the acquisition of infection. A case-control study (25 cases, 75 controls) was used to test the hypothesis that hepatitis E infection was related to consumption of pork products. In a multivariable model, consumption of pork pie [odds ratio (OR) 6·33, 95% confidence interval (CI) 1·41-28·48, P = 0·009] and consumption of ham and sausages purchased from a major UK supermarket chain (OR 10·12, 95% CI 1·68-60·81, P = 0·023) were significantly associated with indigenous infection. The consumption of sausages and ham purchased from the supermarket was highly correlated; however. separate models showed that each variable was significantly associated with infection (OR 7·59, 95% CI 1·81-31·84, P = 0·004 and OR 10·98, 95% CI 1·84-65·35, P = 0·003, respectively). Although contamination of sausages with HEV has previously been shown this study also raises concerns about other processed pork products and whether current practice in preparing these products is sufficient to prevent transmission of HEV.

Public Health Investigation of Two Outbreaks of Shiga Toxin-Producing Escherichia coli O157 Associated with Consumption of Watercress

ABSTRACT An increase in the number of cases of Shiga toxin-producing Escherichia coli (STEC) O157 phage type 2 (PT2) in England in September 2013 was epidemiologically linked to watercress consumption. Whole-genome sequencing (WGS) identified a phylogenetically related cluster of 22 cases (outbreak 1). The isolates comprising this cluster were not closely related to any other United Kingdom strain in the Public Health England WGS database, suggesting a possible imported source. A second outbreak of STEC O157 PT2 (outbreak 2) was identified epidemiologically following the detection of outbreak 1. Isolates associated with outbreak 2 were phylogenetically distinct from those in outbreak 1. Epidemiologically unrelated isolates on the same branch as the outbreak 2 cluster included those from human cases in England with domestically acquired infection and United Kingdom domestic cattle. Environmental sampling using PCR resulted in the isolation of STEC O157 PT2 from irrigation water at one implicated watercress farm, and WGS showed this isolate belonged to the same phylogenetic cluster as outbreak 2 isolates. Cattle were in close proximity to the watercress bed and were potentially the source of the second outbreak. Transfer of STEC from the field to the watercress bed may have occurred through wildlife entering the watercress farm or via runoff water. During this complex outbreak investigation, epidemiological studies, comprehensive testing of environmental samples, and the use of novel molecular methods proved invaluable in demonstrating that two simultaneous outbreaks of STEC O157 PT2 were both linked to the consumption of watercress but were associated with different sources of contamination.

Virology, serology, and demography of hepatitis E viremic blood donors in South East England

Hepatitis E virus (HEV) Genotype 3 (G3) in England comprises two principal phylogenetic groups (Group 1 and Group 2) and can be transmitted by transfusion. Unselected screening identified 79 viremic donors; 76 participated in a follow‐up study.

Outbreak of Shiga toxin-producing E. coli O157 associated with consumption of watercress, United Kingdom, August to September 2013.

An increase in the number of cases of Shiga toxin-producing Escherichia coli O157 PT 2 stx2 infection was reported in the United Kingdom on 9 September 2013. Of the 19 cases, 13 were interviewed, of which 10 reported consuming watercress purchased from one retailer. The retailer recalled pre-packed bagged salads containing watercress on 12 September. The descriptive epidemiology was supported by a case–case study performed after control measures were implemented.

Healthy animals, healthy people: zoonosis risk from animal contact in pet shops, a systematic review of the literature.

Background Around 67 million pets are owned by households in the United Kingdom, and an increasing number of these are exotic animals. Approximately a third of pets are purchased through retail outlets or direct from breeders. A wide range of infections can be associated with companion animals. Objectives This study uses a systematic literature review to describe the transmission of zoonotic disease in humans associated with a pet shop or other location selling pets (incidents of rabies tracebacks and zoonoses from pet food were excluded). Data sources PubMed and EMBASE. Results Fifty seven separate case reports or incidents were described in the 82 papers that were identified by the systematic review. Summary information on each incident is included in this manuscript. The infections include bacterial, viral and fungal diseases and range in severity from mild to life threatening. Infections associated with birds and rodents were the most commonly reported. Over half of the reports describe incidents in the Americas, and three of these were outbreaks involving more than 50 cases. Many of the incidents identified relate to infections in pet shop employees. Limitations This review may have been subject to publication bias, where unusual and unexpected zoonotic infections may be over-represented in peer-reviewed publications. It was also restricted to English-language articles so that pathogens that are more common in non-Western countries, or in more exotic animals not common in Europe and the Americas, may have been under-represented. Conclusions/implications A wide spectrum of zoonotic infections are acquired from pet shops. Salmonellosis and psittacosis were the most commonly documented diseases, however more unusual infections such as tularemia also appeared in the review. Given their potential to spread zoonotic infection, it is important that pet shops act to minimise the risk as far as possible.

Outbreak of Zika virus disease in the Americas and the association with microcephaly, congenital malformations and Guillain–Barré syndrome

Prior to 2007, Zika virus (ZIKV) was generally considered an arbovirus of limited importance, causing a mild self-limiting febrile illness in tropical Africa and Southeast Asia. Now, a large, ongoing outbreak of ZIKV that started in Brazil in early 2015 is spreading rapidly across the Americas and has been potentially linked to congenital malformations (including microcephaly) and Guillain–Barre syndrome (GBS). In England, as of 4 February 2016, five adults have been diagnosed with ZIKV infection following travel to countries currently experiencing a ZIKV outbreak. ZIKV was first isolated from a monkey employed as a sentinel animal in a yellow fever study in the Zika forest, near Entebbe, Uganda, in 1947.1 ZIKV is an RNA arbovirus belonging to the Flaviviridae family, which also includes dengue, Japanese encephalitis and West Nile viruses. The virus is transmitted by female Aedes mosquitoes, especially, Aedes aegypti , which is also an effective vector of dengue and chikungunya virus. Unlike many other mosquito vectors (eg, Anopheles spp. that transmit malaria), Aedes are predominantly day-biting mosquitoes. While the majority of human infections with ZIKV are likely to be acquired via mosquitoes, the virus has been detected in semen2 and blood donors who were asymptomatic at the time of donation,3 raising the possibility of sexual transmission and transmission through blood transfusion, respectively. Up to 80% of individuals infected with ZIKV remain asymptomatic and the remainder usually develop a mild self-limiting febrile illness lasting 4–7 days associated with maculopapular rash, arthralgia, conjunctivitis, itching, myalgia and headache. The infection is seldom severe enough to warrant hospitalisation and ZIKV-related deaths are very rarely reported and are mostly associated with underlying comorbidities. Most recently, a teenager with sickle cell disease in Colombia died after developing acute respiratory distress syndrome and hepatic necrosis.4 There is no vaccine to prevent ZIKV …

Enhanced surveillance for toxoplasmosis in England and Wales, 2008-2012.

A report on Toxoplasma gondii by the UK Advisory Committee on the Microbiological Safety of Food recommended that more accurate figures on the burden of disease in the UK are needed. We present the first 5 years of data from an enhanced surveillance scheme for toxoplasmosis in England and Wales. Between 2008 and 2012, 1824 cases were reported, with an average of 365 each year. There were 1109 immunocompetent cases, the majority presenting with lymphadenopathy, and 364 immunosuppressed cases, with central nervous system and systemic symptoms most frequently reported. There were also 190 pregnant and 33 congenital cases. Of the pregnant cases, 148 were asymptomatic (probably detected during screening), while 28 suffered a fetal loss or stillbirth. The enhanced surveillance system has led to an improvement in the detection of toxoplasmosis in England and Wales. However, numbers are still likely to be an underestimate, biasing towards the more severe infections.

Pork products associated with human infection caused by an emerging phylotype of hepatitis E virus in England and Wales

Since 2010, human hepatitis E infections have increased in England and Wales. Most cases are locally acquired and caused by hepatitis E virus genotype 3 (HEV G3). HEV G3 is linked to the consumption of pork products. The increase is associated with the emergence of a new phylotype, HEV G3-group 2 (G3-2, also known as G3abcdhij). Sixty individuals with confirmed hepatitis E infection and no history of travel outside the UK were recruited: 19 were infected with HEV G3-group 1 (G3-1 or G3efg) and 41 with G3-2. Epidemiological data relating to usual shopping habits and consumption of ham and sausages were analysed together with typing data to identify any associations with HEV phylotype. Study participants who purchased ham and/or sausage from a major supermarket were more likely to have HEV G3-2 infection (Relative risks 1·85, P = 0·06, CI 0·97-3·53). The HEV G3-2 phylotype has not been detected in indigenous UK pigs and it is suggested that human infections could be the result of consumption of products made from pork originating outside the UK. This does not infer blame on the supermarket but the epidemiology of HEV is dynamic and reflects complex animal husbandry practices which need to be explored further.

Zoonotic diseases in South American camelids in England and Wales

The number of South American camelids (SACs) in England and Wales is increasing and with this comes a risk of new and emerging infections. Although classified as livestock, these animals are also treated as pets and may be in regular contact with humans. This paper reviews zoonotic diseases that have been identified in SACs in England and Wales, and which pose a potential risk to human health. We also highlight the importance of surveillance continuing to capture information on infections in SACs for the protection of both public and animal health.