Weekly Digest: Faropenem use in India increasing; More evidence for link between Zika and microcephaly, Guillain-Barré

Use of faropenem, a “last-resort” carbapenem antibiotic that has not been approved in the United States, is increasing rapidly in India, report CDDEP researchers in Clinical Infectious Diseases. Most carbapenems are delivered intravenously, which helps keep them in reserve for serious multi-drug resistant infections, but faropenem is an oral drug. Faropenem consumption increased 154 percent between 2010 and 2014, according to data obtained from IMS health—exceeding use of all other carbapenems combined over the same time period. The researchers warn of a potential increase in carbapenem-resistant Enterobacteriaceae (CRE) due to increased carbapenem use in the region. [Clinical Infectious Diseases]

Global antimicrobial policy can ensure safe, effective antimicrobials for fighting infections by both improving antibiotic access and minimizing excess antibiotic use, writes CDDEP Director Ramanan Laxminarayan in a post on CDC’s Our Global Voices blog. Laxminarayan cites CDDEP research that found that access to antibiotics for children under five with pneumonia in 101 countries could avert about 455,000 deaths annually. The Lancet study also found that universal coverage of children under five with the pneumococcal conjugate vaccine (PCV) could reduce the number of days of antibiotics for pneumonia by about half. A CDC graphic explains the problem of global antibiotic resistance and what can be done to limit it. [CDC Global Voices Blog, CDC Global Health]

Links between Zika virus and microcephaly, Guillain-Barré continue to grow. Scientists in Colombia reported this week that more cases of Guillain-Barré seem to be tied to Zika. A report in CDC’s Morbidity and Mortality Weekly Report (MMWR) announced further evidence of the Zika-microcephaly link: researchers identified Zika virus present in tissue from two miscarriages and two newborns who died within 20 hours of birth with microcephaly. The four Brazilian mothers had previously been infected with Zika but were asymptomatic at time of delivery or miscarriage. According to officials at the Pan American Health Organization (PAHO), if there is a clear link between Zika and microcephaly, Colombia’s current spike in Zika cases should cause a correlated increase in microcephaly in 4 to 5 months. Dr. Marcos Espinal, director of PAHO’s communicable disease department, commented, “Colombia is going to tell us a lot if this link between Zika and microcephaly is really associated. At the moment it is only in Brazil.” [MMWR, NPR, Reuters]

Researchers at Newcastle University have identified an increase in beta-lactam resistance genes in manured soil starting in the mid-1970s. Analyzing data on Danish soil from 1923 to the present, the researchers found the development of antibiotic resistance in soil correlated with records of clinical resistance in hospitals from 1963–1989. They also found that after the Danish ban on non-therapeutic antibiotic use in agriculture in the 1990s, when farmers switched to inorganic fertilizers containing metals with antimicrobial properties, the presence of resistance in soils decreased, reaching pre-industrial levels by 2010. [Newcastle University, Scientific Reports]

Gut microbes play a significant role in the development of childhood stunting—a major consequence of malnutrition. Three studies published this week all contribute to a greater understanding of the role the gut microbiota plays in child development. Researchers analyzed microbiomes of growing children in Bangladesh and Malawi and found that bacteria in the gut of older children who were stunted more closely resembled that of younger children than their non-stunted peers. Several other researchers commented that the research was a major breakthrough in understanding childhood malnutrition; according to infectious disease expert Dr. William Petri, Jr., the studies “are a watershed moment in global health generally, and in nutrition specifically.” [Science]

More than 600,000 people in the United Kingdom have signed a petition asking the UK government to administer meningitis B vaccines to all children under the age of 11. The vaccine, which protects against a bacterial infection that typically affects children less than one year old, is currently only available for free from the government for infants born after May 1, 2015. After a mother posted a photograph and story of her two-year-old daughter, who had died of meningitis B infection, a petition to Parliament asking England’s National Health Service to vaccinate children older than newborns gathered hundreds of thousands of signatures within days. The vaccine, manufactured by GlaxoSmithKline, is also available for private purchase, though GSK announced this week that they are currently experiencing a shortage. [BBC, UK Government and Parliament Petitions]

Antibiotic-resistance genes may be transmitted in Chinese tap water. Researchers at the Chinese Academy of Sciences found evidence of horizontal gene transfer (HGT)—wherein resistance genes are spread from one bacterium to another—in drinking water. The authors believe that under-chlorination has allowed bacteria to survive in the tap water, and say that an increase to 0.3–0.5 mg/L—which is six times the current chlorination level, but still below the WHO recommendation for chlorination levels—may help minimize the spread. [Water Research, South China Morning Post]

A Wolbachia “superinfection”—two strains—may limit transmission of arboviruses in mosquitoes. Wolbachia are bacteria that can infect Aedes aegypti mosquitoes and halt replication of viruses they typically transmit, including dengue, chikungunya and Zika. Research published in PLOS Pathogens describes a new method of introducing Wolbachia into the mosquitoes, which gives infected females a reproductive advantage, resulting in a higher Wolbachia prevalence in the second generation. After this generation, when a second Wolbachia strain was introduced to the mosquito population, the “superinfection” reduced dengue transmission better than the single infection. [EurekAlert, PLOS Pathogens]