OFFICES IN Washington D.C. & New Delhi

Center For Disease Dynamics, Economics & Policy

Weekly Digest: COVID-19 hospitalizations and deaths depend on vaccine timing and durability; Disruptions could lead to a doubling of 2018 reported malaria deaths in Africa; Ten scientific reasons in support of airborne transmission of SARS-CoV-2; Low antibiotic de-escalation rates in hospitalized patients with pneumonia.

COVID-19 hospitalizations and deaths depend on vaccine timing and durability in addition to efficacy. CDDEP researchers developed an age-stratified compartmental model to assess the potential impact of vaccination, assuming increasing vaccine efficacy, coverage, durability, timing, administration rate, and uncertainties in transmission-blocking and symptom reduction. The results indicate that the relative benefit of transmission-blocking heavily depends on the availability and timing of vaccine distribution. The impact of durability on hospitalization and death intensifies as efficacy and coverage increase. Still, the pace of vaccination distribution has a more significant effect than efficacy on short-term outcomes (e.g., reducing peak hospitalizations). Findings have policy implications as prevention measures (e.g., social distancing and mask use) should stay in place longer if the vaccine is distributed more slowly or is less effective at reducing transmission. Decision-makers should also consider the stage of a local outbreak when allocating vaccines. [EClinicalMedicine] 

Ten scientific reasons in support of the airborne transmission of SARS-CoV-2. A systematic review by Heneghan et al., funded by WHO and published in March 2021, states that airborne transmission of SARS-CoV-2 cannot be assumed due to a lack of culture samples. A group of researchers provides ten scientific reasons why airborne transmission is almost certain and argue that the public health implications of stating otherwise are severe. Reasons to assume airborne transmission include but are not limited to the fact that superspreader events and asymptomatic cases account for substantial transmission; transmission is much higher indoors than outdoors; infections have been documented in healthcare facilities with strict contact-and droplet precautions; viable SARS-CoV-2 has been detected in the air in laboratory experiments, as well as, in air filters and building ducts in hospitals. Finally, there is very little evidence to support other forms of transmission (i.e., respiratory droplet or fomite) or to refute airborne transmission. [The Lancet]

 Malaria campaign disruptions could lead to a doubling of 2018 reported malaria deaths in Africa. A new modeling analysis by WHO and partners estimates increases in cases and deaths attributed to malaria, under nine scenarios modeling potential disruptions in access to core malaria control tools in 41 countries. Under the worst-case scenario, in which all insecticide-treated net campaigns are suspended and there is a 75% reduction in access to effective antimalarial medicines, estimated could reach 769 000 deaths, representing a return to malaria mortality levels last seen in the year 2000. [WHO]

Rotavirus vaccination is estimated to be cost-effective in many middle-income countries not eligible for Gavi funding. The rollout of the rotavirus vaccine, now included in most countries’ national immunization programs, has been limited in countries without Gavi support, in part due to concerns over the vaccine’s affordability. To determine the cost-effectiveness of the rotavirus vaccine in middle-income countries, researchers modeled the number of cases, clinic visits, hospitalizations, and deaths averted by rotavirus vaccination in children under 5. They found that from 2020 to 2029, rotavirus vaccines could prevent 77 million cases, 3 million hospitalizations, and 37,900 deaths. Rotavirus vaccination was estimated to be cost-effective in 48 of 62 countries considered in the analysis. Recent improvements in affordability may further improve the cost-effectiveness of rotavirus vaccination in middle-income countries. [The Lancet Global Health]

Low rates of de-escalation of empiric antibiotics in hospitalized patients with pneumonia. A retrospective cohort study including 164 US hospitals assesses antibiotic de-escalation practices following negative cultures in a large cohort of patients (n=14 710) hospitalized with pneumonia and receiving empiric broad-spectrum antibiotics. While recent guidelines suggest de-escalation of broad-spectrum antibiotics in stable patients 48 hours after negative cultures, fewer than one in seven such patients had their extended-spectrum coverage de-escalated by day four. De-escalation practices varied greatly across hospitals, with larger teaching hospitals having the highest de-escalation rates. However, even in those cases, none of the hospitals de-escalated even 40% of its eligible patients, warranting substantial changes in current practice. [Clinical Infectious Diseases]

A cross-sectional survey of Australian pharmacists finds gaps in knowledge of the antimicrobial activity. To assess hospital pharmacists’ self-reported practice and confidence in antimicrobial prescribing and stewardship interventions, researchers conducted a 2017 survey of 439 pharmacists, members of the Society of Hospital Pharmacists of Australia. Fewer than half were confident in identifying appropriate antimicrobial stewardship interventions related to infection-specific factors and bug-drug mismatch. Clinical experience with inpatients, registration for 3-5 years, and recent education on antimicrobial stewardship was associated with higher knowledge scores. Approximately 25% of respondents reported they do not review the appropriateness of cefalexin prescription, an antibiotic often inappropriately prescribed, suggesting that undergraduate and pre-registration education on appropriate prescribing could help bridge the confidence gap between more- and less-experienced pharmacists. [BMC Medical Education]

A comprehensive look at the symptoms of long-haul COVID-19. While the acute symptoms of COVID-19 are well known, there are still questions about the symptoms that occur after the first 30 days of illness. An analysis of data from the US Department of Veteran Affairs involving 73,435 people diagnosed with COVID-19 diagnosis but not hospitalized, and 4,990,835 people without a COVID-19 diagnosis, revealed that the COVID-19 cohort had a higher risk of mortality and health care utilization six months after diagnosis. Beyond the first 30 days of illness, the COVID-19 cohort was at a higher risk of a broad array of clinical manifestations, including neurological disorders, metabolic disorders, cardiovascular disorders, gastrointestinal disorders, and signs and symptoms related to poor general wellbeing, including malaise, fatigue, musculoskeletal pain, and anemia. As the COVID-19 pandemic is being controlled in many parts of the world, its consequences might be felt long after. [Nature]

The mass roll-out of first doses of the COVID-19 vaccines associated with substantial reductions in the risk of COVID-19 hospital admissions in Scotland. A prospective cohort study uses data from the Early Pandemic Evaluation and Enhanced Surveillance of COVID-19 (EAVE II) database to estimate the effectiveness of the Pfizer–BioNTech and Oxford–AstraZeneca vaccines against COVID-19 hospital admission. A single dose of either vaccine is associated with a vaccine effect against COVID-19 hospital admissions ranging from 88% (Astra Zeneca) to 91% (Pfizer–BioNTech) 28 to 34 days after vaccination. When restricted to ages 80 years, the combined vaccine effect against hospital admissions was 83% 28t to 34 days after vaccination. [The Lancet]

People with physical disabilities might be at particular risk for emotional distress, poor quality of life, and low wellbeing during the COVID-19 pandemic. A longitudinal cohort study analyses data on individuals aged 52 years and older from the English Longitudinal Study of Ageing collected in 2018–19 and June to July 2020. Factors such as depression, anxiety, loneliness, quality of life, sleep quality, and amounts of real-time and written social contact were assessed online or by computer-assisted telephone interviews. The findings indicate a significant increase in symptoms of depression (odds ratio 1.78; 95% CI 1.44 to 2.19), anxiety (2.23, 1.72 to 2.89), and loneliness (1.52, 1.26 to 1.84) among people with activities of daily living (ADL) impairment during the COVID-19 pandemic, and highlight the need for additional support and targeted mental health services. [The Lancet Public Health]

Opioid-involved overdose fatalities increased during the lockdown in Cook County, Illinois. Individuals suffering from substance use disorder (SUD) were particularly vulnerable during the early stages of the COVID-19 pandemic, due in part to the heightened economic and social anxiety at the time and lack of access to support networks, in-person treatment, and most importantly, addiction treatment medication. As a result, opioid-involved fatalities in Cook County, Illinois, increased from 23 deaths per week in the 100 weeks before the shutdown to 35.1 deaths per week during the 15 weeks of the initial shutdown and 44.1 deaths per week in the 11 subsequent weeks. However, the authors suggest that SUD’s stigma and poor treatment networks before the pandemic are more to blame for these fatalities’ increase than the shutdown itself. [JAMA Insights]