PRESS-NEWS.org - Press Release Distribution
PRESS RELEASES DISTRIBUTION

Target canine 'superspreaders' to halt killer disease and cull fewer dogs, study suggests

A new way to test for the parasite which causes the fatal disease leishmaniasis could help control its spread to humans and stop dogs being needlessly killed in parts of South America

2014-01-10
(Press-News.org) Contact information: Orin Courtenay
orin.courtenay@warwick.ac.uk
44-024-765-24550
University of Warwick
Target canine 'superspreaders' to halt killer disease and cull fewer dogs, study suggests A new way to test for the parasite which causes the fatal disease leishmaniasis could help control its spread to humans and stop dogs being needlessly killed in parts of South America A new way to test for the parasite which causes the fatal disease leishmaniasis could help control its spread to humans and stop dogs being needlessly killed in parts of South America. Zoonotic visceral leishmaniasis is a vector-transmitted parasitic infection which can be fatal if left untreated. It generally affects the poorest of the poor, particularly malnourished children in developing countries, with an estimated 200,000 to 400,000 new cases in humans annually according to World Health Organisation figures. Dogs have been shown to be the 'reservoir' for the parasite, which is transmitted to humans via bites from female sandflies that have fed on blood from infected dogs. In Brazil tens of thousands of dogs that test positive for anti-Leishmania antibodies are killed every year in an effort to control the disease. However the presence of antibodies does not necessarily mean that the dog is symptomatic or is infectious to sandflies so that it can pass the parasite onto humans. This means that it is likely many dogs are culled unnecessarily, which usually results in dog owners acquiring a new dog - often a puppy that has not encountered the parasite before and that is then likely to become infected, thus helping to drive transmission.

Previous studies have questioned the effectiveness of these measures in controlling leishmaniasis in dogs and humans and the policy is also undermined by significant levels of non-compliance among dog owners. An alternative approach is outlined in a new study by scientists at the University of Warwick who have shown that parasite load – a count of the number of parasites present in a dog's skin tissue – is related to its infectiousness to sandflies. Their long-term study of dogs in the Brazilian Amazon indicates that a small number of 'superspreader' dogs are responsible for the majority of the spread of the parasite. They found that about ten per cent of dogs are host to 90 per cent of the parasites potentially available to sandflies identified in the study population and that these superspreader dogs are responsible for the majority (more than 80 per cent) of all transmission events to sandflies. The study also looked at crab-eating foxes living in the same area and found that they had parasite numbers comparable to those of non-infectious dogs - a finding that backs up the evidence of previous studies by the Warwick researchers that these foxes are not likely to play a significant role in the spread of the disease. Dr Orin Courtenay of the School of Life Sciences at the University of Warwick led the study. He said: "The current control of visceral leishmaniasis in Brazil includes killing dogs on a large scale and at great cost. This doesn't appear to have a significant effect on either canine or human infection rates and, not surprisingly, this strategy has been called into question on scientific, logistic and ethical grounds by both the Brazilian and international communities. "Our study suggests an alternative approach - targeting control at these highly infectious and often the sickest dogs. This approach could be more cost-effective in controlling the spread of this devastating disease in humans than the current policy. "Instead of canine testing for presence or absence of anti-Leishmania antibodies, we suggest testing directly for parasite loads in the skin of the dog where sandflies like to bite, or to alter the current antibody test to threshold levels reflecting superspreader status. "This way you can identify dogs most likely to be highly infectious to sandflies – it is these dogs that pose the biggest threat to human health. "Targeting control measures on these 'superspreaders' - the small fraction of dogs which are responsible for the majority of transmission - should not only be a far more effective way to control the spread of the parasite, it would also result in fewer dogs being killed. "We now hope to take our research to the next stage, which is to trial these threshold-based tests to see what effect that may have on controlling the spread of leishmaniasis." The longitudinal study, led by the University of Warwick, was published in the journal PLOS Neglected Tropical Diseases. The team are now carrying out a similar study on the role of rodents and dogs in the transmission of a disfiguring mucocutaneous form of leishmanisis, working with the Fundação Oswaldo Cruz (Fiocruz) in Brazil, thanks to a link forged through a Science Without Borders grant. ### Orin Courtenay is available on+44 (0)2476 524550 or email: orin.courtenay@warwick.ac.uk University of Warwick press officer Anna Blackaby can be contacted on +44 (0)2476 575910 or a.blackaby@warwick.ac.uk The study Heterogeneities in Leishmania infantum infection: using skin parasite burdens to identify highly infectious dogs is available here (once embargo has lifted) http://www.plosntds.org/article/info%3Adoi%2F10.1371%2Fjournal.


ELSE PRESS RELEASES FROM THIS DATE:

New clues to how bacteria evade antibiotics

2014-01-10
New clues to how bacteria evade antibiotics Scientists have made an important advance in understanding how a subset of bacterial cells escape being killed by many antibiotics. Cells become "persisters" by entering a state in which they stop replicating and ...

Prediction of the future flu virus

2014-01-10
Prediction of the future flu virus Every year, influenza outbreaks claim hundreds of thousands of human lives. Though vaccination against flu is fairly efficient, the disease is difficult to exterminate because of the high evolutionary rate of the flu virus. ...

Researchers develop test to predict early onset of heart attacks

2014-01-10
Researchers develop test to predict early onset of heart attacks LA JOLLA, CA – A new "fluid biopsy" technique that could identify patients at high risk of a heart attack by identifying specific cells as markers in the bloodstream has been developed by a group of ...

Spinal cord findings could help explain origins of limb control

2014-01-10
Spinal cord findings could help explain origins of limb control Zebrafish study connects data between fish and mammalian locomotion

Discovery may aid vaccine design for common form of malaria

2014-01-10
Discovery may aid vaccine design for common form of malaria A form of malaria common in India, Southeast Asia and South America attacks human red blood cells by clamping down on the cells with a pair of proteins, new research at Washington University ...

Study: Heavy viewers of 'Teen Mom' and '16 and Pregnant' have unrealistic views of teen pregnancy

2014-01-10
Study: Heavy viewers of 'Teen Mom' and '16 and Pregnant' have unrealistic views of teen pregnancy Many believe teen mothers have an enviable quality of life, a high income and involved fathers BLOOMINGTON, Ind. -- The creator of MTV's "16 and Pregnant" and "Teen Mom" ...

SF State astronomers discover new planet in Pisces constellation

2014-01-10
SF State astronomers discover new planet in Pisces constellation SAN FRANCISCO, Jan. 9, 2014 -- A team led by SF State astronomer Stephen Kane has discovered a new giant planet located in a star system within the Pisces constellation. The planet, perhaps ...

High costs of research at universities made worse by funding gap

2014-01-10
High costs of research at universities made worse by funding gap 'Real' costs of research not met by funding available to universities TAMPA, Fla. (Jan. 9, 2014) – Although more opportunity exists for university-based researchers to be innovative, and ...

With instruments in space and on earth, NJIT solar experts monitor the massive solar storm

2014-01-10
With instruments in space and on earth, NJIT solar experts monitor the massive solar storm The first powerful "X-class" solar flare of 2014, in association with another solar phenomenon, a giant cloud of solar particles known as a coronal mass ejection (CME), erupted from ...

LSUHSC research reveals structure of master regulator and new drug target for autism, cervical cancer

2014-01-10
LSUHSC research reveals structure of master regulator and new drug target for autism, cervical cancer New Orleans, LA – A team of scientists at LSU Health Sciences Center New Orleans has discovered the structure of the active form of E6-associated ...

LAST 30 PRESS RELEASES:

SwRI-built instruments to monitor, provide advanced warning of space weather events

Breakthrough advances sodium-based battery design

New targeted radiation therapy shows near-complete response in rare sarcoma patients

Does physical frailty contribute to dementia?

Soccer headers and brain health: Study finds changes within folds of the brain

Decoding plants’ language of light

UNC Greensboro study finds ticks carrying Lyme disease moving into western NC

New implant restores blood pressure balance after spinal cord injury

New York City's medical specialist advantage may be an illusion, new NYU Tandon research shows

Could a local anesthetic that doesn’t impair motor function be within reach?

1 in 8 Italian cetacean strandings show evidence of fishery interactions, with bottlenose and striped dolphins most commonly affected, according to analysis across four decades of data and more than 5

In the wild, chimpanzees likely ingest the equivalent of several alcoholic drinks every day

Warming of 2°C intensifies Arctic carbon sink but weakens Alpine sink, study finds

Bronze and Iron Age cultures in the Middle East were committed to wine production

Indian adolescents are mostly starting their periods at an earlier age than 25 years ago

Temporary medical centers in Gaza known as "Medical Points" (MPs) treat an average of 117 people daily with only about 7 staff per MP

Rates of alcohol-induced deaths among the general population nearly doubled from 1999 to 2024

PLOS One study: In adolescent lab animals exposed to cocaine, High-Intensity Interval Training boosts aversion to the drug

Scientists identify four ways our bodies respond to COVID-19 vaccines

Stronger together: A new fusion protein boosts cancer immunotherapy

Hidden brain waves as triggers for post-seizure wandering

Music training can help the brain focus

Researcher develop the first hydride ion prototype battery

MIT researchers find a more precise way to edit the genome

‘Teen’ pachycephalosaur butts into fossil record

Study finds cocoa extract supplement reduced key marker of inflammation and aging

Obesity treatment with bariatric surgery vs GLP-1 receptor agonists

Nicotinamide for skin cancer chemoprevention

Novel way to ‘rev up’ brown fat burns calories, limits obesity in mice

USC Stem Cell-led team makes major advance toward building a synthetic kidney

[Press-News.org] Target canine 'superspreaders' to halt killer disease and cull fewer dogs, study suggests
A new way to test for the parasite which causes the fatal disease leishmaniasis could help control its spread to humans and stop dogs being needlessly killed in parts of South America