Weekly Digest: Zika virus travel alert; Pharma industry antibiotic declaration

High-level resistance of Salmonella Typhi to gatifloxacin in Nepal indicates that fluoroquinolones should no longer be used against enteric fever. A randomized trial published in the Lancet Infectious Diseases and co-authored by Global Antibiotic Resistance Partnership (GARP)-Nepal working group chairman Buddha Basnyat compared gatifloxacin (a fourth-generation fluoroquinolone) with ceftriaxone (a third-generation cephalosporin) for uncomplicated enteric fever in Nepal. Contrary to expectations based on previous experience, the failure rate with gatifloxacin was much higher—26 percent—than the 7 percent failure of ceftriaxone in patients with culture-confirmed enteric fever. The story is more complicated, however. In half of the study’s 239 patients, no pathogen could be cultured, and in those patients, the failure rate was reversed: much higher with ceftriaxone than gatifloxacin (and neither agent was completely satisfactory). The results support a need to change treatment guidelines and underscores the importance of developing point-of-care diagnostics to distinguish among common infections, particularly in poor countries.  [Lancet]

Can coalitions between neighboring countries increase vaccination coverage by limiting free-riding? CDDEP researchers investigated this question in a study published in the Journal of the Royal Society Interface. Without an international body governing vaccine administration, countries can “free-ride” on their neighbors’ higher vaccination coverage across a porous border, taking advantage of “herd immunity.” Using a model to predict the effects of voluntary coalitions between countries, which include counter-measures to avoid free-riding (e.g., penalties for noncompliance, trade sanctions or links to other agreements), they found that coalitions do lead to higher immunization rates. Coalitions of countries with significant differences in economic and/or epidemiologic status also work surprisingly well in the model, increasing vaccination across countries, leading to consistency in vaccine coverage among the member nations. [Journal of the Royal Society Interface]

More than 80 pharmaceutical companies, including Merck and GlaxoSmithKline, signed a declaration released at the World Economic Forum in Davos, Switzerland urging governments to invest in development of new antibiotics, vaccines and diagnostics and to develop principles for the conservation of antimicrobials. CDDEP Director Ramanan Laxminarayan, quoted in a National Geographic article, commented that the role pharmaceutical companies play in antibiotic conservation—including in the discovery and production of diagnostics and vaccines—is as important as the role companies play in the development of new antibiotics, and greater resources are needed to meet the global threat of resistance. [Bloomberg, National Geographic]

The U.S. Centers for Disease Control and Prevention (CDC) has issued a travel alert for pregnant women traveling to 19 Latin American and Caribbean countries where Zika virus has recently spread. Incidence of the virus in pregnant women has been linked to a birth defect, microcephaly, that has now affected more than 4,000 newborns in Brazil—about one percent of babies born in the most affected area. Cases of the virus have been reported in the United States in Texas, Florida, Illinois and Hawaii, including the first case of Zika-associated microcephaly in Hawaii last week. According to Hawaiian health officials, the mother likely became infected with the virus while living in Brazil in May 2015. [CDC, The New York Times, BBC]

The U.S. Food and Drug Administration (FDA) has approved design and labeling changes in duodenoscopes made by one of the manufacturers implicated in outbreaks of carbapenem-resistant Enterobacteriaceae. The company, Olympus, plans to voluntarily recall models currently in use in U.S. hospitals to fix the defect by installing a tighter seal on the elevator channel mechanism. Scopes will then be returned to hospitals. [Infection Control Today]

Gavi, the Vaccine Alliance, has signed a $5 million deal with Merck to license the Ebola vaccine. The vaccine, VSV-EBOV, showed promise in early trials but is still under development. The deal will require Merck to keep 300,000 doses ready for further trials or clinical use if necessary, and will eventually hand over licensing to Gavi, allowing the NGO to stockpile vaccines in the event of another Ebola emergency. [BBC]

The American College of Physicians (ACP) and CDC issued updated guidance on antibiotic use for acute respiratory tract infections (ARTIs). The guidance, for adult cases of respiratory infections, updates their 2001 prescribing advice. The change is that instead of immediate antibiotics, patients with common colds, uncomplicated bronchitis, sore throats and uncomplicated sinus infections should not be given antibiotics after the first consultation, but only if symptoms persist or worsen. [Annals of Internal Medicine, CIDRAP]

President Obama’s State of the Union promise to “wipe out” malaria globally may be promising more than is possible, writes to New York Times White House reporter and former South Asia correspondent Gardiner Harris in a recent letter. Though the U.S. President’s Malaria Initiative, started under President George W. Bush, has helped reduce the malaria burden considerably through a range of interventions, more than 200 million new malaria cases occurred globally this past year. Even if the President’s funding request to Congress is granted, eradicating malaria worldwide may not be possible. According to Dyann F. Wirth, Director of the Harvard Malaria Initiative, “I do not believe that we have the arsenal that could lead to eradication. But it is true that the disease is interruptible. That’s been done in many places, and that is not trivial.” [The New York Times]

A blood test may be able to distinguish bacterial from viral infections based on gene expression of the immune elements fighting off the infection. The diagnostic, developed by researchers at Duke University, distinguished with 87 percent accuracy whether an illness was caused by a bacterial infection, a viral infection or had a non-infectious cause. The test currently takes about 10 hours, with a goal of reducing the time to just one hour. [New Scientist]

CDDEP is hiring a Communications Intern for its D.C. office. For more information and to apply, visit cddep.org/jobs.