Larvicide reduces 80% of Aedes in Brazilian city
A study yesterday in PLoS Medicine shows that the larvicide pyriproxyfen (PPF) greatly reduces the number of adult Aedes mosquitoes, the vector that transmits Zika, yellow fever, and dengue.
Aedes mosquitoes are notoriously hard to control, as they tend to live indoors and can concentrate in urban populations. Most insecticides only produce a transient reduction of adult populations, and breeding sites can be hard to target. To counter these factors, researchers used adult mosquitoes to disseminate particles of PPF to breeding sites.
From February 2014 to March 2015, researchers working in Manacapuru, Brazil, measured mosquito populations throughout the city. Beginning in March 2015, they placed plastic cups containing PPF and tap water in 100 dwellings and analyzed mosquito populations after 5 months of citywide PPF dissemination, 3 months of focal PPF dissemination around Aedes-infested dwellings, and 3 months after dissemination ended.
According to the study, the number of Aedes juvenile samples decreased by 79% to 92%, and mean adult Aedes emergence fell from 1,077 per month at baseline to 50.4 per month during PPF dissemination. The emergence of young female Aedes mosquitoes dropped by 96% to 98%.
"Mosquito-disseminated PPF has potential to block mosquito-borne virus transmission citywide, even under adverse scenarios," the authors write. "Our results signal new avenues for mosquito-borne disease prevention, likely including the effective control of Aedes-borne dengue, Zika, and chikungunya epidemics."
Jan 17 PLoS Med study
Study: 76% of Ebola survivors have symptoms 1-year after discharge
Researchers who followed 802 survivors of the 2013-2016 Ebola outbreaks in West Africa in Guinea said that the majority of patients (76%) had significant sequelae 1 year after discharge. They report their finding in The Lancet Infectious Diseases.
The most frequent post-infection symptoms included generalized musculoskeletal pain (38%), fever and fatigue (40%), headache (35%), depression (17%), abdominal pain (22%), and ocular disorders (18%). The group will be followed for up to 24 months post-discharge from any of Guinea's four Ebola treatment centers.
The study also confirmed that Ebola virus DNA lingers for several months in semen: Of the 188 men included in the study, 10 (5%) tested positive for Ebola at a maximum of 548 days after disease onset.
About one third (26%) of 793 patients reported feeling stigmatized by community and family years 1-year post-infection, which led to significant reports of depression and anxiety among survivors.
Jan 13 Lancet Infect Dis study
PAHO reports 4,000 new chikungunya cases
The Pan American Health Organization (PAHO) in the first 2 weeks of 2017 reported 4,008 new suspected, confirmed, and imported chikungunya cases, mostly in Brazil, bringing the 2016-17 total in the Americas to more than 500,000.
All but 241 of the cases were recorded in the most recent update, on Jan 13. The final PAHO report of 2016 also included 108 new cases, after the agency reported more than 56,000 new infections the week before.
Brazil reported data for week 50 of 2016, which was the week of Dec 11. It noted 3,811 new cases, bringing its 2016-17 total to 412,468. Bolivia had 191 new cases (20,997 total), while Costa Rica logged 60 new cases and 3,421 total.
Most countries, however, have not reported new cases for several weeks. Brazil, which accounted for 82% of all chikungunya cases in 2016 and was responsible for the big jump in cases in the Dec 23 update, has yet to report on the most recent 4 weeks.
Countries in the Americas have now reported 502,298 suspected, confirmed, and imported chikungunya cases last year and early this year. The outbreak began in late 2013 on the Caribbean island of St. Martin and has now sickened at least 2,380,738 people.
Jan 13 PAHO update
Jan 6 PAHO update
Studies indicate antimicrobial-coated sutures reduce surgical infections
Two new papers in the British Journal of Surgery found that antimicrobial-coated sutures are effective at reducing surgical-site infections (SSIs) and could produce substantial cost savings.
In one paper, a meta-analysis of 21 randomized clinical trials involving 6,462 patients that were conducted from 1990 through 2015, investigators found that the use of sutures coated with triclosan, when compared with uncoated sutures, reduced the risk of SSIs by 15%, cutting the number of SSIs per 1,000 procedures by 39.
In the other paper, an economic meta-analysis of 34 randomized trials published from 2005 through 2016, investigators found that using antimicrobial sutures produced a mean savings of £91.25 ($111.92) per surgical procedure across all wound classes compared with sutures without the coating.
"Antimicrobial sutures ought to be included into SSI care bundles and provide a further significant saving to National Health Service (England) surgical practice," David Leaper, MD, ChM, lead author of the economic analysis, said in a press release from journal publisher Wiley.
The US Centers for Disease Control and Prevention (CDC) estimates that there were 157,500 SSIs from any inpatient surgery in the United States in 2011, the most recent year for which data are available. Preventing SSIs from occurring is seen as a critical part of efforts to reduce the use of antibiotics.
Jan 17 Br J Surg study
Jan 17 Br J Surg economic study
Jan 17 Wiley press release
Center for Health Security announces partnership with Johns Hopkins
The Center for Health Security, a group centered around the use of science and policies to prevent and respond to outbreaks and other public health emergencies, yesterday joined the Johns Hopkins Bloomberg School of Public Health.
The center was founded by D.A. Henderson, MD, MPH, who died last August and is best known for leading the global campaign that eradicated smallpox, in 1998. The center was affiliated with Johns Hopkins in its early years, then joined the University of Pittsburgh Medical Center in 2003.
In a statement from the group, Tom Inglesby, MD, the center's director and chief executive officer, said the center's mission is a perfect fit with the Johns Hopkins Bloomberg School of Public Health, because they share a commitment to improving global health and protecting lives through large-scale change. "Moving to the Bloomberg School will expand the reach of the center and help us collaborate with and tap into the universe of great talent at Johns Hopkins," he said.