More than 1,300 suspected plague cases reported in Madagascar
The World Health Organization (WHO) reported a total of 1,309 suspected cases, including 93 deaths, in an update yesterday on the plague outbreak in Madagascar. The case-fatality rate for the outbreak is now 7%.
The numbers reflect an increase of 12 cases and 9 fewer deaths from the WHO's previous update on Oct 20.
The number of new plague cases continued to decline for the second week in a row, with 12 affected regions reporting no new cases. All suspected cases were reported between Aug 1 and Oct 24, with the majority (882 or 67%) confirmed as pneumonic plague, the only type of plague transmitted from person to person. The WHO said as of Oct 24, 94% of traced case contacts had received prophylactic antibiotics.
A total of 186 suspected cases are unspecified and undergoing further testing. Seventy-one healthcare workers have been infected in this outbreak, but none of those cases have proved fatal.
Plague is endemic in parts of Madagascar, and though the outbreak began with one epidemiologically linked cluster, the WHO warned that the risk at the national level is still "very high." The risk of international spread, however, is deemed "very low" because of the short incubation period for pneumonic plague.
Oct 26 WHO situation report
In other plague news, the European Centre for Disease Prevention and Control (ECDC) released new guidelines for detecting plague on ships and airplanes, and for using personal protective equipment (PPE) in healthcare settings with suspected plague patients.
For traveling, plague should be suspected when a person has traveled from an active outbreak area and reports persistent fever, cough, and trouble breathing. Prophylactic antibiotics may be given to any passengers or crew that came into contact with the person.
Plague patients should be isolated, if possible, in healthcare settings and healthcare workers should wear protective coverings, gloves, and masks.
Oct 26 ECDC travel guidelines
Oct 26 ECDC PPE guidelines
Pace of Yemen cholera cases stabilizing
The world's largest cholera outbreak has slowed some, according to a WHO update yesterday. There have now been 862,858 suspected cases of cholera reported in Yemen, including 2,177 associated deaths.
The outbreak began a year ago in October of 2016, but picked up speed in April, when more than 5,000 cases per day were being reported. Officials now see the outbreak as stable.
"The overall case-fatality rate remains low (0.25%)," the WHO’s outbreak report said. "There has been a modest decrease in the number of suspected cholera cases and deaths compared to previous weeks, and the overall trend appears to be stable."
Ongoing conflict and a collapsing infrastructure have fueled the outbreak, which is projected to reach 1 million cases by the end of the year.
Oct 26 WHO update
Study looks at relationship between hospitals' antibiotic use, resistance
Canadian researchers have found that hospital-specific antibiotic usage was associated with increased, rather than decreased, antibiotic susceptibility in a study yesterday in Infection Control and Hospital Epidemiology.
In the multicenter observational ecological study, researchers evaluated the relationship between antibiotic use and antibiotic resistance in common nosocomial bacteria by looking at the antibiograms and antibiotic consumption data from 30 acute care hospitals in Ontario. From the antibiograms, antibiotic susceptibilities of Escherichia coli, Klebsiella spp, Pseudomonas aeruginosa, Enterobacter spp, Enterococcus spp, and Staphylococcus aureus were extracted. Multivariate regression was performed, with the antibiotic susceptibility of the individual pathogens as the primary outcome, and antibiotic consumption as the main predictor.
Multivariate regression analyses showed that increased antibiotic consumption, expressed in defined daily doses per 1,000 patient days (DDDs/1,000 PD), was associated with decreased antibiotic susceptibility for P aeruginosa (-0.162% per DDD/1,000 PD). But that trend was not considered statistically significant. In contrast, increased antibiotic consumption predicted increased antibiotic susceptibility for E coli (0.173% per DDD/1,000 PD), Klebsiella (0.124% per DDD/1,000 PD), Enterobacter (0.194% per DDD/1,000 PD), Enterococcus (0.309% per DDD/1,000 PD), and non-significantly for S aureus (0.012% per DDD/1,000 PD).
The authors say the results may be explained by the community origins of infections caused by many of the evaluated pathogens. If these infections are derived from strains acquired before hospitalization, they suggest, hospital-specific antibiotic usage wouldn't necessarily predict resistance rates.
The only pathogen that showed decreased susceptibility was P aeruginosa, which is most likely to be acquired in the hospital. And because antibiograms use patients' initial microbial cultures and are therefore weighted toward community-acquired pathogens, clinicians may be basing their prescribing decisions on community-weighted resistance prevalence, which would lead them to choose antibiotics with less resistance.
Oct 26 Infect Control Hosp Epidemiol abstract