Blood donor screening finds 13% Zika rate in Puerto Rico last year
In a study that expands on an earlier analysis, screening of blood donations in Puerto Rico last spring and summer found a 13% incidence of Zika virus, according to a study yesterday in Emerging Infectious Diseases.
Researchers led by experts from the Centers for Disease Control and Prevention analyzed date from the screening of blood donation collected by the two largest blood centers in Puerto Rico from Apr 3 through Aug 12, 2016. Assuming a 9.9-day duration of viremia (virus in the blood), the investigators extrapolated that 469,321 people on the island were infected during that period, for an estimated cumulative incidence of 12.9% (range, 11.0% to 15.4%).
They further estimated that 69,675 women of reproductive age were infected in that time span, or 9.7% of the total population of such women.
In an earlier analysis published last June, the same group estimated a 0.5% prevalence for the virus in blood from Apr 3 through Jun 11, 2016, but the incidence was rising steadily, to a high of 1.1% in the last week studied.
Mar 6 Emerg Infect Dis study
Jun 17, 2016, CIDRAP News story on earlier results
Espirito Santo state, Brazil at risk for yellow fever transmission: WHO
The World Health Organization (WHO) said today that the entire Brazilian state of Espirito Santo is at risk for yellow fever transmission, as the mosquito-borne disease continues to creep toward Brazil's Atlantic coast.
The WHO said the rise of cases in Espirito Santo warrants new vaccination recommendations for the state: All travelers should receive yellow fever vaccine 10 days prior to visiting Espirito Santo.
The WHO made the recommendation after "taking into account the speed of spread observed in Espirito Santo State, the proximity to the urban area of Vitoria of epizootics, and human cases under investigation for yellow fever infection."
As of Mar 2, the Pan American Health Organization (PAHO) said there were 1,368 cases of confirmed or suspected yellow fever in Brazil, 83% of them in Minas Gerais state. The case-fatality rate is approximately 33%.
Mar 7 WHO recommendation
Mar 2 PAHO update
Cholera cases in Yemen begin to decline
Despite 1,598 new suspected cases of cholera reported in Yemen since Feb 26, the WHO said today in its weekly update that the current outbreak of acute, watery diarrhea is starting to decline. No new deaths were reported this week.
"The trend of suspected cholera cases per week appears to be on the decline in most districts or governorates. Nearly 85% of the new cases recorded since the last update was in 10 districts within Al Hudaydah, Al Bayda, Hajjah, Sana’a and Ta'izz governorates," the WHO report said.
Yemen's cholera outbreak began last October, and the outbreak has been made worse by the movement of internally displaced persons and inconsistent public health infrastructure throughout the country.
To date, there have been 22,181 suspected cases of cholera, including 103 deaths, with a case-fatality rate of 0.45%.
Mar 7 WHO update
Cochrane C difficile review favors vancomycin
An updated Cochrane Review on antibiotic treatment for Clostridium difficile infection (CDI) has found that vancomycin is superior to metronidazole and fidaxomicin is superior to vancomycin.
The review looked at 22 randomized controlled trials involving 3,215 patients with diarrhea who had recently received an antibiotic for an infection other than C difficile. Most of the patients enrolled in the studies had mild-to-moderate CDI, and most of the studies were active comparator studies in which vancomycin was compared to 11 other antibiotics for safety and efficacy. The primary outcomes assessed in the review were sustained symptomatic cure (defined as resolution of diarrhea and no recurrence of CDI) and bacteriologic cure.
In four of the studies, the reviewers found moderate evidence that vancomycin was superior to metronidazole for achieving sustained symptomatic cure, with 79% of vancomycin patients achieving symptomatic cure compared to 72% of metronidazole patients. Two large studies provided moderate evidence that fidaxomicin was more effective than vancomycin, with 71% of fidaxomicin patients achieving symptomatic cure compared to 61% of vancomycin patients. Two pooled studies provided low evidence that teicoplanin may be more effective than vancomycin for achieving symptomatic cure.
The only side effects attributed the antibiotics were nausea and temporary elevation of liver enzymes. Since most of the studies excluded severe CDI patients, the reviewers could not draw firm conclusions on the effectiveness of antibiotic treatment on severe CDI.
The authors note that the differences in effectiveness between these antibiotics were not large, and that metronidazole costs significantly less than either vancomycin or fidaxomicin. They recommend larger trials to determine if teicoplanin is as effective as the other antibiotics, and suggest a trial comparing metronidazole and teicoplanin—the two cheapest options.
Mar 3 Cochrane review
Chinese study finds high rates of susceptibility in UTIs
A study yesterday in BMC Infectious Diseases found fairly low rates of non-susceptibility in urinary tract infections (UTIs) in China from 2010 through 2014, with carbapenems and amikacin retaining the highest susceptibility rates over the study period.
Chinese researchers studied the minimum inhibitory concentrations of 12 antibiotics for 4,332 gram-negative bacilli in UTI samples from 21 hospitals in 16 cities obtained during the 5-year study period. Fully 88.5% of the isolates were Enterobacteriaceae. Of those, 63.2% were Escherichia coli and 12.2% Klebsiella pneumoniae.
The authors found that the two carbapenems tested, ertapenem and imipenem—as well as amikacin piperacillin-tazobactam—had the highest susceptibility rates again E coli, ranging from 92.5% to 98.7%. Against K pneumonia, the most potent antibiotics were imipenem (92.6% susceptibility), amikacin (89.2%), and ertapenem (87.9%).
The non-Enterobacteriaceae isolates showed lower susceptibilities to the 12 antibiotics. The researchers also noted that rates of extended-spectrum beta-lactamase (ESBL) declined slowly over the 5 years: in E coli from 68.6% to 59.1%, in K pneumoniae from 59.7 to 49.2%, and in Proteus mirabilis from 40.0 to 26.1%. ESBL rates, though, differed among the five regions of the country.
Mar 6 BMC Infect Dis study