ESR plans research into gut infections
Scientists at ESRwill spend $1.3million unravelling the mysteries of a gastro bug that has alarmed experts.
In the past 12 months there have been 1177 notified cases of yersiniosis, more than double the number of cases five years ago.
The bacterium Yersinia enterocolitica causes fever, diarrhoea and abdominal pain. In 12 per cent of cases, patients need hospital treatment.
Doctors know the bacterium is transmitted through food, especially undercooked pork, but suspect other foods may be implicated, said ESR science leader Dr Brent Gilpin.
Other likely sources include pets, farm animals and water.
Yersinia is hard to culture – it’s sometimes called hellsinia – and researchers today have genetic and other tools unavailable in earlier times.
Starting in the new year, ESR will follow up on yersiniosis cases in Canterbury. They will analyse stool samples and ask patients to fill in detailed questionnaires about their activities before they fell ill, he said.
They will sequence the bacterium’s genome to learn more about it and hope to trace the sources more convincingly.
‘‘We want to know more than why rates are increasing, but how people are becoming infected and why it affects some [people] more than others,’’ Gilpin said.
The researchers hope to collect data from 250 people over 36 months, using money from the Health Research Council.
‘‘This will allow the investigators to generate new data on the severity of the illness and quantify the overall disease burden, aswell as determining if there are differences with pathogenicity and antimicrobial
resistance among Yersinia from different sources.
‘‘The ultimate goal of the study is to help improve surveillance activities and help devise control strategies to ultimately reduce yersiniosis and other enteric diseases.’’
This sort of analysis and work halved New Zealand’s rate of campylobacter from 2006-2019, after poultry was identified as the most common vector for that gastro bug.
The available data show that Ma¯ori have lower rates of yersiniosis, but ‘‘we think that notified rates severely underrepresent the actual disease burden among Ma¯ori,’’ Gilpin said.
Many peoplewho get this sickness do not seek medical care or don’t get diagnosed with yersiniosis.
‘‘By understanding what contributes to these low notification rates, measures can be put in place to reduce any resulting health inequities.’’
The Canterbury District Health Board notified the highest number of cases in 2018, but other DHBs had higher rates per 100,000 people.
Canterbury was selected for the research because it had a
large enough population for statistical purposes and was small enough to make source tracing attainable, Gilpin said.
Collaborators from the US, Canada, Europe and Australia saw value in the programme and it was expected the results would be internationally important.
‘‘ESR collects data for more than 50 notifiable diseases from public health units across the country. As the number of yersiniosis cases increased, our experts were alarmed.
‘‘It became clear to us that we needed to apply ESR’s tools and expertise, like source-tracking, to thismystery so thatwemight help reduce the burden of yersiniosis,’’ Gilpin said.
Last week, the HRC announced 32 grants worth $14.4m to investigate:
HPV screening instead of smears to detect cervical cancer, which could reduce rates by 15 per cent ($1.4m).
■ Improving blood safety and donor selection ($1.4m).
Improving primary care service delivery for those impacted by violence ($1.4m).
Tihei Rangatahi Programme – Improving hauora/oranga services for rangatahi Ma¯ori ($1.4m).