Browsing by Author "Stevenson B"

Now showing 1 - 4 of 4
  • Thumbnail Image
    Item
    A cross-sectional investigation of Leptospira at the wildlife-livestock interface in New Zealand
    (PLOS, 2023-09-06) Moinet M; Oosterhof H; Nisa S; Haack N; Wilkinson DA; Aberdein D; Russell JC; Vallée E; Collins-Emerson J; Heuer C; Benschop J; Stevenson B
    There has been a recent upsurge in human cases of leptospirosis in New Zealand, with wildlife a suspected emerging source, but up-to-date knowledge on this topic is lacking. We conducted a cross-sectional study in two farm environments to estimate Leptospira seroprevalence in wildlife and sympatric livestock, PCR/culture prevalence in wildlife, and compare seroprevalence and prevalence between species, sex, and age groups. Traps targeting house mice (Mus musculus), black rats (Rattus rattus), hedgehogs (Erinaceus europaeus) and brushtail possums (Trichosurus vulpecula) were set for 10 trap-nights in March-April 2017 on a dairy (A) and a beef and sheep (B) farm. Trapped wild animals and an age-stratified random sample of domestic animals, namely cattle, sheep and working dogs were blood sampled. Sera were tested by microagglutination test for five serogroups and titres compared using a Proportional Similarity Index (PSI). Wildlife kidneys were sampled for culture and qPCR targeting the lipL32 gene. True prevalence in mice was assessed using occupancy modelling by collating different laboratory results. Infection profiles varied by species, age group and farm. At the MAT cut-point of ≥ 48, up to 78% of wildlife species, and 16-99% of domestic animals were seropositive. Five of nine hedgehogs, 23/105 mice and 1/14 black rats reacted to L. borgpetersenii sv Ballum. The sera of 4/18 possums and 4/9 hedgehogs reacted to L. borgpetersenii sv Hardjobovis whilst 1/18 possums and 1/9 hedgehogs reacted to Tarassovi. In ruminants, seroprevalence for Hardjobovis and Pomona ranged 0-90% and 0-71% depending on the species and age group. Titres against Ballum, Tarassovi and Copenhageni were also observed in 4-20%, 0-25% and 0-21% of domestic species, respectively. The PSI indicated rodents and livestock had the most dissimilar serological responses. Three of nine hedgehogs, 31/105 mice and 2/14 rats were carrying leptospires (PCR and/or culture positive). True prevalence estimated by occupancy modelling in mice was 38% [95% Credible Interval 26, 51%] on Farm A and 22% [11, 40%] on Farm B. In the same environment, exposure to serovars found in wildlife species was commonly detected in livestock. Transmission pathways between and within species should be assessed to help in the development of efficient mitigation strategies against Leptospira.
  • Thumbnail Image
    Item
    Leptospirosis, melioidosis, and rickettsioses in the vicious circle of neglect.
    (PLOS, 2025-01-23) Tshokey T; Ko AI; Currie BJ; Munoz-Zanzi C; Goarant C; Paris DH; Dance DAB; Limmathurotsakul D; Birnie E; Bertherat E; Gongal G; Benschop J; Savelkoel J; Stenos J; Saraswati K; Robinson MT; Day NPJ; Graves SR; Belmain SR; Blacksell SD; Wiersinga WJ; Stevenson B
    The global priorities in the field of infectious diseases are constantly changing. While emerging viral infections have regularly dominated public health attention, which has only intensified after the COVID-19 pandemic, numerous bacterial diseases have previously caused, and continue to cause, significant morbidity and mortality-deserving equal attention. Three potentially life-threatening endemic bacterial diseases (leptospirosis, melioidosis, and rickettsioses) are a huge public health concern especially in low- and middle-income countries. Despite their continued threat, these diseases do not receive proportionate attention from global health organizations and are not even included on the WHO list of neglected tropical diseases (NTDs). This, in turn, has led to a vicious circle of neglect with continued, yet conceivably preventable, hospitalizations and deaths each year especially in the vulnerable population. This is a call from a group of multi-institutional experts on the urgent need to directly address the circle of neglect and raise support in terms of funding, research, surveillance, diagnostics, and therapeutics to alleviate the burden of these 3 diseases.
  • Thumbnail Image
    Item
    Regenerative agriculture in Aotearoa New Zealand - research pathways to build science-based evidence and national narratives.
    (2021-02-22) Grelet G; Lang S; Merfield C; Calhoun N; Robson-Williams M; Horrocks A; Dewes A; Clifford A; Stevenson B; Saunders C; Lister C; Perley C; Maslen D; Norton D; Selbie D; Chan D; Burns E; Le Heron E; Crampton E; Curran-Cournane F; Doolan-Noble F; Griffin F; Good H; Pinxterhuis I; Todd J; Vernon J; Su J; Cavanagh J; Laubach J; King J; Jones J; Orwin K; MacMillan K; Minor M; Anderson M; Buckley M; Harcombe M; McGlone M; Davidson M; Barry M; Taitoko M; Kirschbaum M; Donovan M; Conland N; Stanley-Clarke N; Masters N; Schon N; Mason N; Gregorini P; Mudge P; Tapsell P; Bruce-Iri P; Tait P; Roudier P; Mellor R; Teague R; Gregory R; Price R; Holdaway R; Dynes R; Lavorel S; O'Connell S; Letica S; Belliss S; McNeill S; Apfelbaum S; Driver T; Fraser T; Baisden T; Kerner W
  • Thumbnail Image
    Item
    Supporting older adults in pandemics.
    (Massey University, 2022-12-01) MacDonald C; Mooney M; Johnston D; Tassell-Matamua N; Alefaio S; Stevenson B; Alpass F; Stephens C