Nursing homes, exposure to younger people tied to COVID-19 death rate
A Swedish study in The Lancet Healthy Longevity yesterday revealed a higher risk of COVID-19 mortality among older people—ages 70 and above—living in nursing homes as well as with or in close contact with younger people, underlining the importance of community spread and individual points of transmission to older adults.
Higher rates of COVID-19–related hospitalization and mortality have been demonstrated for older adults in congregate settings. The study used data on residence type, household size, crowding, age structure, neighborhood density, and confirmed area cases and deaths in Stockholm. No formal lockdown was implemented in Sweden during the study period from Mar 12 to May 8, and protection of vulnerable populations relied on voluntary shielding and physical distancing measures.
The researchers reported 1,301 COVID-19 deaths among older people in a sample of 274,712 individuals, with residential setting a significant factor in COVID-19 mortality. Care homes were associated with the highest mortality rate (233 per 1,000 people per year), followed by apartment blocks and detached houses (26 and 16 per 1,000 per year, respectively). Those living in care homes were four times as likely to die of COVID-19 as those in independent housing (hazard ratio [HR], 4.13; 95% confidence interval [CI], 3.49 to 4.90).
The age of household contacts was also a significant mortality risk factor, with the lowest mortality rates among those living exclusively with others aged 66 or older. Living with someone younger than 66 years old was associated with a 60% increase in COVID-19 mortality, compared with living in a household composed exclusively of individuals aged 66 and older (HR, 1.60; 95% CI, 1.31 to 1.95).
These figures highlight the importance of social mixing among age-groups as a significant factor in mortality risk and point to the inadequacy of voluntary shielding and physical distancing to protect older adults.
In a related commentary, two US experts wrote, "The passive stance taken in Sweden to avoid a generalised lockdown resulted in increased deaths, not only in care homes, but also among community-dwelling older adults. … The Swedish experience shows that COVID-19 mortality will continue to place its heaviest burden on older adults unless a comprehensive public health strategy is implemented going forward."
Oct 27 Lancet Healthy Longev study
Oct 28 Lancet Health Longev commentary
Oct 27 Lancet news release
Study: 4% of Brazilian hospital visitors asymptomatic
A single-center study in The International Journal of Infectious Diseases yesterday points to the possibility of COVID-19 transmission by asymptomatic visitors in healthcare settings and highlights the inadequacy of protective measures.
Concerns about hospital-acquired infections have centered around asymptomatic patients, but this study points to the potential risk of asymptomatic hospital visitors as an underestimated source of viral shedding and in-hospital transmission.
The researchers tested all visitors to São Paolo Hospital in São Paolo, Brazil, on Aug 29, finding that 4% of visitors (6 in 150) had asymptomatic COVID-19. Of the six asymptomatic visitors identified using reverse transcriptase-polymerase chain reaction testing (RT-PCR) with nasopharyngeal sampling, one tested positive 20 days earlier but showed no symptoms at the time of the visit. Another COVID-19–positive visitor developed symptoms the day following the visit, and the other four showed no symptoms through final assessment 14 days after testing.
Two of the six patients visited by a COVID-19–positive visitor subsequently tested positive. The researchers noted that multiple visits by the same visitor could have played a role in transmission to the infected patients. And since visitors are frequently close contacts of patients before hospitalization—one was a spouse—transmission may have occurred before the hospital interaction.
"A recent large US study showed a low incidence of hospital-acquired COVID-19. However nosocomial infections still occur, and may be closely related to asymptomatic and presymptomatic individuals' potential of transmission," the study authors wrote.
Universal masking in healthcare settings may breed false confidence in reduced transmission risks, the study authors suggest. Healthcare facilities may need to consider local infection rates and active screening of visitors—versus symptom-only screening—to protect patients from in-hospital transmission, they add.
Oct 27 Int J Infect Dis study
Declining COVID-19 mortality rates in UK likely due to multiple factors
A study across 108 UK trusts—which can each operate more than one hospital—showed that 30-day all-cause mortality rates for COVID-19 patients admitted to high dependency units (HDUs) and intensive care units (ICUs) declined significantly from Mar 1 through Jun 27.
After looking at data from 21,082 critical care patients, researchers found that those admitted in late March had a 71.6% survival rate in HDUs and 58.0% in ICUs; by the end of June, survival rates were 92.7% and 80.4%, respectively. This change was consistent across hazard ratios, patient characteristics, and geography, according to findings published in Critical Care Medicine.
Lead researcher John Dennis, PhD, of the University of Exeter, said in a university press release, "This suggests the improvement in death rates in more recent months is not simply due to younger, or previously healthier, people being admitted to critical care. A number of factors are likely to be at play here, including improved understanding of how to manage COVID-19 amongst doctors, and the introduction of effective treatments."
Indeed, the RECOVERY trial started in early April—which included drugs such as dexamethasone—and other potential treatments such as the antiviral remdesivir became more common as time went on. Perhaps just as important, after March, hospitals were less overwhelmed with patients.
The highest mortality rate occurred in early March for both those in HDUs and ICUs, with a mortality rate of 28.4% in the HDU during the week of Mar 22 and a rate of 42.0% in the ICU during the week of Mar 15. After the week of Mar 29, though, the mortality rate began improving by 12.7% per week in the HDU and 8.9% per week in the ICU. The one anomaly to this trend was the lack of improvement seen in the ICUs of North East and Yorkshire.
Oct 26 Crit Care Med study
Oct 27 University of Exeter press release
WHO notes recent flu detections, mainly H3N2, in some countries
Though global flu levels are still lower than expected for this time of year, some Northern Hemisphere countries reported some detections, the World Health Organization (WHO) said in an update posted today that covers roughly the first half of October.
The agency urged caution in interpreting flu trends because of the likely impacts from COVID-19 restrictions and surveillance. In the United States, though influenza-like illness (ILI) levels overall are below the national baseline, activity in children ages 0 to 4 years old was just above that marker. Canada reported an increase in flu detections, though at a lower level than previous seasons.
Europe reported sporadic flu detections, and China's ILI activity appears to have increased to levels seen over the past three flu seasons.
In tropical countries, Ivory Coast and Mali reported some flu positives, and in South Asia, ILI activity rose slightly in Afghanistan, with a further increase in Cambodia and flu detections—mainly from H3N2—in Laos. And elsewhere, flu activity stayed above the epidemic threshold in Argentina, where H3N2 and influenza B are cocirculating.
Globally, of 82,257 respiratory specimens tested at WHO network labs, only 172 were positive for flu. Of the positive samples, 62.8% were influenza A, and, of subtyped influenza A samples, 93.9% were H3N2.
Oct 26 WHO global flu update
