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Weekly Digest: Increasing global consumption of Watch antibiotics reflects stewardship challenges; Hospital masking policy associated with reduced rates of COVID-19 in healthcare workers; Antibiotics recommended for crop production at high rates in Southeast Asia.

Weekly Digest: Increasing global consumption of Watch antibiotics reflects stewardship challenges; Hospital masking policy associated with reduced rates of COVID-19 in healthcare workers; Antibiotics recommended for crop production at high rates in Southeast Asia.

Increasing global consumption of Watch antibiotics reflects stewardship challenges. A CDDEP-led analysis of global antibiotic consumption in each AWaRe category found that the growth of Watch antibiotic consumption was nearly four times greater than that of Access antibiotic consumption over 15 years. The study found that global per capita antibiotic consumption increased 90.9 percent in Watch antibiotics and 26.2 percent in Access antibiotics between 2000 and 2015. The substantial increase in the proportion of Watch antibiotic consumption was driven primarily by low- and middle-income countries, which saw an increase of 165 percent (2.0 to 5.3 defined daily doses per 1,000 inhabitants per day [DIDs]), compared to just 27.9 percent in high-income countries (HICs) (6.1 to 7.8 DIDs). Of concern, the proportion of countries that met the WHO national-level target of at least 60 percent of a country’s total antibiotic consumption comprising Access antibiotics, decreased from 76 percent in 2000 to 55 percent in 2015. Findings reflect challenges in improving appropriate antibiotic use- particularly in LMICs. [The Lancet Infectious Diseases]



COVID-19 vaccine candidates show early promise. Several vaccine candidates against the novel coronavirus have shown early promise in clinical trials including two adenovirus-vectored vaccines, developed by researchers in the UK (Oxford University) and China. Both vaccines, ChAdOx1 nCoV-19 and Ad5, produced an immune response and were deemed safe in phase 1/2 trials including 1,077 individuals across the UK and 508 individuals in Wuhan, China, respectively. While results are promising, phase 3 trials are needed to determine if the vaccines are able to prevent COVID-19 in recipients. [The Lancet: Oxford, China]

Hospital masking policy associated with reduced rates of COVID-19 in healthcare workers. In March 2020, a large health care system in Massachusetts implemented a policy requiring all healthcare workers and patients to wear surgical masks in an effort to control the spread of COVID-19. The implementation of universal masking was associated with a significantly lower rate of novel coronavirus positivity among healthcare workers, which declined from 14.65 to 11.46 percent between April 11thand 30th, 2020, decreasing 0.46 percent per day on average. Prior to the intervention, the rates of COVID-19 positivity among healthcare workers increased exponentially from 0 to 21.32 percent, increasing 1.16 percent per day on average. Authors note that while other measures such as social distancing may have contributed to the reduced positivity rates, findings support universal masking as part of infection prevention and control strategies in healthcare settings. [JAMA]

More US adults are wearing face masks in public. Results of two online surveys indicated that the rate of US adults who reported wearing cloth face masks in public increased from 61.9 percent in April to 76.4 percent in May 2020 following a recommendation from the White House Coronavirus Task Force and the US Centers for Disease Control and Prevention (CDC). The largest increases in mask use within the one-month period were reported among white respondents (54.3 to 75.1 percent), people 65 years and older (36.6 to 79.2 percent), and those living in the Midwest (43.7 to 73.8 percent). Positive attitudes toward mask-wearing, behavioral intention, personal agency, perceived norms, and perceived susceptibility to the novel coronavirus were among the factors associated with mask use. Authors of the analysis suggest that messaging surrounding face mask use should be positive and highlight the benefits of wearing face coverings in public. [CDC MMWR]

Dexamethasone may benefit COVID-19 patients receiving respiratory support. Preliminary results from a trial in the UK revealed that the steroid dexamethasone was tied to decreased mortality among individuals hospitalized for COVID-19. Overall 28-day mortality was significantly lower among the patient group randomized to receive dexamethasone compared to the standard of care group (22.9 vs. 25.7 percent), although mortality varied by level of respiratory support at randomization. The incidence of death in the dexamethasone group was lower among patients receiving invasive mechanical ventilation (29.3 vs. 41.4 percent) or oxygen alone (23.3 vs. 26.2 percent) compared to the control, but no significant difference was observed between groups among patients who were not receiving any form of respiratory support. [NEJM]

Study estimates 0.7% COVID-19 infection fatality rate. In a pre-print review and meta-analysis of 24 studies, researchers estimated that the aggregated infection fatality rate (IFR) of the novel coronavirus is 0.68 percent (95% CI 0.53-0.82 percent). IFR estimates varied considerably across studies from 0.09 to 1.60 percent, so researchers emphasize that the aggregate IFR may not be the ‘true’ point estimate and likely varies by population. [MedRxiv]

Benefits of routine immunization outweigh excess risks of COVID-19 in Africa. In a benefit-risk analysis across Africa, researchers found that the health benefits of sustaining routine childhood immunization outweigh the excess risks of COVID-19 attributable to vaccination visits. The study found that in a high impact scenario including the effect of diphtheria, tetanus, pertussis, hepatitis B, Haemophilus influenzae type b, Streptococcus pneumoniae, rotavirus, measles, meningitis A, rubella, and yellow fever vaccines on children under five, for each COVID-19 death related to vaccination visits, another 84 child deaths would be prevented through sustained immunization. The greatest benefit-risk ratio of routine vaccination in Africa vs. the excess risks of COVID-19 was observed among vaccinated children, followed by their siblings and caregivers. [The Lancet Global Health]


Drug Resistance and Global Health 

Antibiotics recommended for crop production at high rates in Southeast Asia. Researchers in the UK analyzed an international database of recommendations for crop management across 32 low- and middle-income countries (LMICs) over 8 years and found that in some years, nearly 10 percent recommended an antibiotic for rice production. A total of 11 antibiotics, several considered medically-important, were recommended for crop production, although recommendations varied by region. Antibiotic use in crops was widespread across Southeast Asia, most commonly in rice, tomato, and citrus fruit– a majority for bacterial diseases, but some for insect infestations, for which antibiotics provide no benefit. Findings suggest that antibiotic use in crop production, specifically in Southeast Asia, is more common than previously thought and may contribute to the rise of antibiotic resistance. [CABI Agriculture and Bioscience,]

Inappropriate pre-surgery antibiotics common in Australia. A survey of Australian hospitals between 2016 and 2019 found that inappropriate prescribing of pre-surgery antimicrobial prophylaxis was high (42.3 percent). An analysis of the survey results identified allergy status, surgical procedure group, and the presence of prosthetic material as significant indicators of cefazolin and aminoglycoside appropriateness. Prescribing of broad-spectrum antimicrobials, including third/fourth-generation cephalosporins (83.3 percent) and metronidazole (67.9 percent), was the most common reason for inappropriateness. Authors note that results of this study should guide antimicrobial stewardship programs, especially focusing on procedures where pre-surgery broad-spectrum antimicrobial use is common.  [JAC-Antimicrobial Resistance]

Flu drug may prevent infection in household contacts. Results of a randomized controlled trial in Japan indicated that a drug for uncomplicated influenza, baloxavir, was successful in preventing flu among household contacts following exposure to the virus. The study, which included 752 household contacts and 545 index patients, found that the risk of clinical influenza or influenza infection regardless of symptoms was significantly lower among household contacts randomly assigned to receive baloxavir compared to placebo (adjusted risk ratio: 0.14; 0.43, respectively). The drug proved efficacious as postexposure prophylaxis among high-risk, young, and unvaccinated contacts as well. [NEJM]

Vaccine tied to declining rates of meningococcal disease in US adolescents. Researchers at the US Centers for Disease Control and Prevention (CDC) conducted a cohort study using surveillance data and found that the introduction of the quadrivalent meningococcal conjugate vaccine (MenACWY) in the US was tied to declining rates of meningococcal disease in adolescents. The incidence of meningococcal disease decreased from 0.61 cases per 100,000 population prior to vaccine introduction (2000-2005) to 0.15 cases per 100,000 following the booster dose recommendation (2011-2017). Rates of decline of new cases caused by C, W, and Y serogroups accelerated 2 to 3 times among vaccinated adolescents following MenACWY introduction, and highest rates of decline were observed in states with high vaccine coverage. Study authors note that the introduction of the MenACWY vaccine alone did not account for the decline in incidence of meningococcal disease in the US, but it contributed to a reduced burden among adolescents. [JAMA Pediatrics]