Strategy proposed for testing deer, elk herds for chronic wasting disease
A "proactive hunting surveillance" approach of shooting and testing deer likely to harbor the causative agent of chronic wasting disease (CWD) without leading to undesirable population declines achieved a 99% CWD-free rate within 3 to 5 years, in comparison to 10 years using the typical preemptive sampling strategy, according to a Norwegian modeling study published today in Nature Communications.
Researchers applied a model of proactive hunting surveillance to a recent outbreak of CWD in wild reindeer in Norway to determine if it was effective in detecting CWD in its early stages. It involved killing small numbers of calves and yearlings while culling more adults—particularly males—which are more likely to harbor detectable levels of infection. Males also are less likely than females to limit population growth.
The authors noted that while preemptive culling of infected herds of deer and elk—and other animals infected with transmissible diseases—has long been used to control infectious wildlife disease outbreaks, this approach conflicts with biodiversity conservation goals.
Using professional sharpshooters can help offset public concerns about culling herds because they have lower rates of wounding and not killing the animals, the authors said.
They found that involving local stakeholders in the new approach helped reduce conflicts, but "considerable controversy among laymen nevertheless arose when the quotas were known to the general public," the authors wrote. "Changing the attitudes of hunters and stakeholders will be challenging and controversies are likely to persist when implementing alternative harvesting regimes."
CWD is a fatal, contagious neurologic disease involving abnormally folded proteins called prions, which produce lesions in the brains of infected deer, elk, and caribou. While there have been no reports of CWD in humans, the possibility remains a concern.
Sep 1 Nat Commun study
Stewardship intervention tied to significantly less carbapenem use
A policy involving mandatory infectious disease (ID) consultation and post-prescription review with feedback (PPRF) was tied to in sustained reduction in the use of carbapenem antibiotics at two hospitals in Washington state, researchers reported yesterday in Clinical Infectious Diseases.
In a retrospective study conducted at the University of Washington Medical Center (UWMC) and Harborview Medical Center (HMC), researchers evaluated the impact of the policy on antibiotic consumption and clinical outcomes over a 6-year period, comparing the pre-intervention period with the post-intervention period. The policy, which was prompted by a critical shortage of meropenem in November 2015, required mandatory ID consultation and PPRF for all meropenem and imipenem use beyond 72 hours.
The primary outcome of the study was meropenem and imipenem days of therapy (DOT) per 1,000 patient-days. Secondary outcomes included meropenem and imipenem initiation and 30-day mortality and hospital length of stay (LOS).
There were 4,066 and 2,552 patients in the pre- and post-intervention periods, respectively. During the pre-intervention period, meropenem and imipenem DOT/1,000 patient-days remained stable, then dropped sharply after introduction of the intervention, falling by 72.1% (95% confidence interval [CI], 66.9% to 76.6%; P < 0.001) at UWMC and by 43.6% (95% CI, 20.7% to 59.9%; P = 0.001) at HMC, with a sustained effect over 4 years. In addition, although the intervention did not address use until 72 hours after initiation, there was a significant decline in meropenem and imipenem initiation in the post-intervention period, with a 64.9% reduction (95% CI, 58.7% to 70.2%; P < 0.001) at UWMC and a 44.7% reduction (95% CI, 28.1% to 57.4%; P < 0.001) at HMC.
No significant differences were found between the pre- and post-intervention periods in 30-day mortality or hospital LOS.
"Our study shows that PPRF combined with a potential mandatory ID consultation can serve as an impactful yet relatively low-resource intervention that can significantly reduce carbapenem consumption without compromising clinical outcomes," the authors of the study wrote.
Aug 31 Clin Infect Dis abstract
Study finds no link between maternal flu vaccination and autism
In the latest in a body of literature showing flu vaccines not tied to autism, a study today in the Annals of Internal Medicine found no link between maternal H1N1 flu vaccination during pregnancy—including in the third trimester—and the risk for autism spectrum disorder (ASD) in children.
The study was conducted at the Karolinska Institutet in Sweden, where researchers looked at 39,726 infants with prenatal exposure to the vaccine (13,845 during the first trimester), and 29,293 unexposed infants born in 2009 and 2010. During a follow-up of more than 6 years, the researchers found that 394 (1.0%) vaccine-exposed and 330 (1.1%) vaccine-unexposed children had a diagnosis of ASD.
Two recent studies had been unable to rule out an association between maternal H1N1 vaccination and ASDs, but this is the largest and most comprehensive study to look at the exposure and risk.
"Our null findings are important since some people have suspected that vaccinations could cause autism, and the anti-vaccine movement seems to be growing in the Western world," said lead author, Jonas F Ludvigsson, MD, professor at the Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, in a press release.
Sep 1 Annals of Intern Med study
Aug 31 Karolinska Institutet press release
WHO details recent polio cases in Sudan
The World Health Organization (WHO) today shared more details about the reemergence of polio in Sudan, which involves circulating vaccine-derived poliovirus type 2 (cVDPV2), following an initial report in the middle of August of two such cases. The detections marked Sudan's first confirmed polio cases since 2009.
The first patient is a 4-year-old child from South Darfur state whose paralysis began in March, and the second is a 3-year-old child from Gedarif state with a paralysis onset of Apr 1. Both states are near international borders, and both children received their last bivalent oral polio vaccination in 2019.
The initial investigation found that the cVDPV2 viruses are linked to those first detected in October 2019 and are circulating in Chad and Cameroon. Eleven suspected cases in six different states have been reported in Sudan. Positive environmental samples have also been reported in the capital city, Khartoum.
A national task force for outbreak response has been established and includes international partners. The WHO said the risk of further spread in central Africa and the Horn of Africa is high, especially with large-scale population movements. A more through assessment is under way, and the WHO urged all countries to strengthen their surveillance for acute flaccid paralysis.
Sep 1 WHO statement
Aug 14 CIDRAP News scan "Polio reemerges in Sudan, affects 5 other countries"