Genomics accurately predicts antimicrobial resistance in Staphylococcus pseudintermedius collected as part of Vet-LIRN resistance monitoring.

Whole-genome sequencing (WGS) has changed our understanding of bacterial pathogens, aiding outbreak investigations and advancing our knowledge of their genetic features. However, there has been limited use of genomics to understand antimicrobial resistance of veterinary pathogens, which would help identify emerging resistance mechanisms and track their spread. The objectives of this study were to evaluate the correlation between resistance genotypes and phenotypes for Staphylococcus pseudintermedius, a major pathogen of companion animals, by comparing broth microdilution antimicrobial susceptibility testing and WGS. From 2017-2019, we conducted antimicrobial susceptibility testing and WGS on S. pseudintermedius isolates collected from dogs in the United States as a part of the Veterinary Laboratory Investigation and Response Network (Vet-LIRN) antimicrobial resistance monitoring program. Across thirteen antimicrobials in nine classes, resistance genotypes correlated with clinical resistance phenotypes 98.4 % of the time among a collection of 592 isolates. Our findings represent isolates from diverse lineages based on phylogenetic analyses, and these strong correlations are comparable to those from studies of several human pathogens such as Staphylococcus aureus and Salmonella enterica. We uncovered some important findings, including that 32.3 % of isolates had the mecA gene, which correlated with oxacillin resistance 97.0 % of the time. We also identified a novel rpoB mutation likely encoding rifampin resistance. These results show the value in using WGS to assess antimicrobial resistance in veterinary pathogens and to reveal putative new mechanisms of resistance.

Deaths from poisoning in New Zealand: 2001-2002.

AIMS: To describe the epidemiology and toxicology of poisoning deaths in New Zealand for 2001 and 2002. METHODS: Poisoning mortality data for 2001 and 2002 were collected from the Coronial Service Office (CSO) as part of the New Zealand chemical injury surveillance system. RESULTS: There was 235 and 234 poisoning deaths in 2001 and 2002 respectively, an annual rate of 6.3 [95% CI of 5.5 to 7.1] deaths per 100,000 population for both years. Two-thirds (67.0%) of the deaths were intentional. The 25-44 year age group had the largest number of cases and highest age-specific rate (123 deaths, 11.1 [95% CI: 9.3-13.2] per 100,000 in 2001 and 119 deaths, 10.7 [(95% CI: 9.0-12.8] per 100,000 in 2002). Over two-thirds (68.9%) of the deaths were male. In 2001, the European rate was slightly higher than that for Maori but rates for the two ethnicities were similar in 2002. Geographically, West Coast District Health Board (DHB) had the highest rates. Rates increased with increasing deprivation. Nearly two-thirds (64.3%) of the intentional deaths were attributed to carbon monoxide. Methadone, morphine or heroin, and ethanol were the leading causes of the unintentional deaths. CONCLUSIONS: The rate of poisoning deaths in New Zealand is comparable with other industrial countries as is the prominence of poisoning as a leading method of suicide.

Antidepressant poisoning deaths in New Zealand for 2001.

AIM: To compare the rates of death per volume of drug dispensed for antidepressants in New Zealand. METHODS: Deaths from antidepressant poisonings were identified from the reports of coronial inquiries for New Zealand in 2001. Prescriptions for antidepressant medications were identified from the PharmHouse database from 1 January 2001 to 31 December 2001. The rates of deaths (95% CI) per prescription, tablet/capsule or defined daily dose were calculated for individual antidepressants and classes of antidepressant. RESULTS: There were 200 poisoning deaths recorded in the database for New Zealand in 2001. Antidepressants were involved in 41 deaths, and death was attributed to an antidepressant in 23 cases. There were 5.52 (95% CI 3.85-7.68) deaths per 100 000 prescriptions for tricyclic antidepressants (TCAs) and 2.51 (1.57-3.79) deaths per 100 000 prescriptions for selective serotonin reuptake inhibitors (SSRIs). There was marked variability in rates of death per volume of drug dispensed between individual antidepressants. CONCLUSIONS: SSRIs have lower rates of death per volume of drug dispensed than TCAs and there is also variation in these rates within these classes of drugs. Toxicity in overdose should be considered when prescribing antidepressants.

Comparison of the fatal toxicity index of zopiclone with benzodiazepines.

BACKGROUND: Zopiclone is a hypnosedative structurally unrelated to the benzodiazepines but operating at the same receptor complex. Although zopiclone has been used in clinical practice for many years, relatively little is known of its relative toxicity in comparison with other hypnosedatives. METHOD: Deaths, where hypnosedatives were implicated, in New Zealand (NZ) in 2001 were identified from a chemical injury database. Prescription and aggregate defined daily dose (DDD) data forNZ in 2001 were obtained from a national prescribing database. Rates of death per prescription and DDD, and relative rates between individual hypnosedatives and benzodiazepines, and their respective 95% CI were calculated. RESULTS: Of the 200 poisoning deaths in NZ for 2001, 39 involved hypnosedatives, and zopiclone was involved in 12. Hypnosedatives were the sole agents in only one death and were the primary agents in eight deaths. Zopiclone was the sixth most commonly involved agent in poisoning deaths in NZ in 2001. The relative rate of death per prescription (95% CI) and DDD (95% CI) of zopiclone compared with benzodiazepines were 1.04 (0.49-2.05) and 0.59 (0.28-1.16), respectively. The relative rates of death per DDD (95% CI) for alprazolam and chlormethiazole compared with the other sedatives/anxiolytics were 6.2 (1.6-17.0) and 20.9 (2.5-79.8) respectively. CONCLUSIONS: The fatal toxicity for zopiclone was not significantly different from that for benzodiazepines as a group when adjusted for usage, whereas alprazolam and chlormethiazole had greater toxicity. Hypnosedatives are contributory factors rather than primary substances in poisoning deaths.