Thursday, October 29, 2009

Atypical Scrapie

Via ProMED-mail: the New Zealand Ministry of Agriculture and Forestry reports on a case of atypical scrapie.

MAFBNZ Principal International Adviser Dr Stuart MacDiarmid says global knowledge about atypical scrapie/Nor 98 is evolving. The widely accepted mainstream scientific view is that it occurs spontaneously or naturally in very small numbers of older sheep in all sheep populations around the world.
"This positive detection of atypical scrapie/Nor 98 in a sheep from New Zealand's national flock reinforces that view. Every country that has conducted sufficient surveillance for atypical scrapie/Nor 98 has found it in their flocks. This includes most Scandinavian and EU countries, the UK, the USA and Canada," he says.
The detection does not change New Zealand's status as free from scrapie.

Wednesday, October 07, 2009

Mad Elk and Mad Fish

Via ProMED-mail: last month, the New York Times reported on the spread of CWD among elk via fecal-oral transmission, due to preclinical shedding of prions.

Dr. Aiken said prions tended to bind to clay in soil and to persist indefinitely. When deer graze on infected dirt, prions that are tightly bound to clay will persist for long periods in their intestinal regions. So there is no chance chronic wasting disease will be eradicated, he said. Outside the laboratory, nothing can inactivate prions bound to soil. They are also impervious to radiation.

Also, Practical Fish Keeping reported last month on a study of mad cow and scrapie transmissibility to fish:

The authors found that while the bream never displayed clinical signs of spongiform encephelopathies during the study period, the brains of TSE-fed fish sampled two years after challenge showed signs of neurodegeneration and accumulation of deposits that reacted positively with antibodies raised against sea bream PrP. The control groups, fed with brains from uninfected animals, showed no such signs.

Thursday, October 01, 2009

Swine Flu Shots vs. Seasonal Flu Shots

Via ProMED-mail: temperatures are still high in Canada, where the Globe and Mail reports that two and a half provinces have rebelled against seasonal flu shots in reaction to as-yet-unpublished research showing that a seasonal flu shot makes people more susceptible to swine flu.

The hodge-podge of vaccination strategies comes after a controversial, unpublished study suggested that people under 50 are twice as likely to contract the H1N1 virus if they have received a seasonal flu shot compared to unvaccinated people.
With no data revealing the optimal way of rolling out vaccines against the looming double threat of seasonal flu and the pandemic swine flu virus, the abrupt changes by provinces and territories could create disarray in inoculation programs, with fewer people turning up for either shot, potentially resulting in more cases of severe illness.
New Brunswick's public health authorities, skeptical about the science behind the Canadian study, have moved up seasonal flu shots for all their residents to October before proceeding to the pandemic vaccine campaign. Meanwhile, Quebec and Nunavut are deferring their seasonal flu campaigns until after their H1N1 mass vaccination clinics.