COVID-19 Scan for Jun 01, 2020

News brief

Asymptomatic carriers unknowingly spread COVID-19 in Asia, reports say

A multicenter study published yesterday in Travel Medicine and Infectious Disease shows that 60% of asymptomatic (symptom-free) COVID-19 patients in Sichuan province, China, were diagnosed as having pneumonia on their first computed tomography (CT) scan.

The study involved 100 asymptomatic and 411 symptomatic coronavirus patients in hospitals in 21 cities and 47 counties or districts from Jan 25 to Feb 20.

The researchers also found that patients without symptoms were younger and came from higher-altitude areas with less resident mobility and more defined epidemiologic history than patients with symptoms but had similar rates of underlying conditions.

Of initially asymptomatic patients, 27.4% later developed symptoms, two of them older patients who developed severe symptoms. No asymptomatic patients died. One patient was believed to have transmitted the virus during the incubation period.

And in Influenza and Other Respiratory Viruses, a May 30 letter details likely asymptomatic COVID-19 spread in a household and school after travelers returned to Brunei after attending a religious event in Malaysia from Feb 28 to Mar 2. Of the more than 4,000 confirmed cases linked to the event, 19 from Brunei tested positive for COVID-19 after returning home, where they infected 52 others.

The authors said that their findings support the use of testing and longitudinal surveillance of asymptomatic close contacts, as well as widespread testing at mass gatherings in places with known community spread.
May 31 Travel Med Infect Dis study
May 30 Influenza Other Respir Viruses letter

Low COVID-19 prevalence found among pregnant, postpartum women

Universal testing found an overall low prevalence of COVID-19 among pregnant and postpartum women in Seattle, Washington, according to a new study published in Clinical Infectious Diseases.

The study was conducted at University of Washington-associated labor and delivery units and clinics from Mar 2 through Apr 15. The researchers used rapid tests for SARS-CoV-2, the virus that causes COVID-19, which returned results in 6 to 8 hours. Women were tested in the hospital, at outpatient clinics, and via drive-through testing.

Researchers found a (2.7% [5 of 188]) prevalence of SARS-CoV-2 among pregnant and postpartum patients after initiating universal testing. Among symptomatic patients (22.2% [4/18]) tested positive, and among 170 asymptomatic patients, two were positive or inconclusive; repeat testing at 24 hours was negative.

The authors said the low prevalence in pregnant and postpartum women, as compared to that of New York City, is reflective of virus trends in Seattle.

"Despite low numbers of additional cases identified, universal screening of pregnant patients provides important surveillance information due to the representativeness of this population to the greater community," they concluded.
May 30 Clin Infect Dis study

CDC study finds no secondary COVID-19 transmission of early US case

A Centers for Disease Control and Prevention (CDC) contact tracing investigation of one of the first US COVID-19 patients identified no secondary transmission among close contacts on molecular or serologic testing after 14 days of last exposure.

The study, published late last week in Emerging Infectious Diseases, identified 11 coworkers, 31 waiting-room contacts at an urgent care clinic, and 8 unprotected healthcare contacts of the patient, a 35-year-old man returning to Washington state on Jan 15 after visiting Wuhan, China.

Thirty-eight of the 50 contacts (78%) were interviewed, and 11 (29%) reported unprotected interactions with the patient, who had worked while ill. Thirty-seven (74%) tested negative for coronavirus, and none of the 23 who underwent serologic testing for 6 weeks had detectable antibodies against SARS-CoV-2, the virus that causes COVID-19. The presence of antibodies would indicate previous infection.

All contacts were monitored daily for 14 days. Median contact age was 44 years (range, younger than 1 to 86 years), and 25 (50%) were male. Eight contacts developed symptoms, including cough, headache, runny nose, sore throat, and fever.

Of the 11 coworkers who had face-to-face interactions with the patient, four (36%) had been exposed to the patient over 1 day, and seven (64%) had been exposed over 2 days for 2 to 90 minutes. Six coworkers (55%) said they had touched the patient. Three of seven coworkers who had attended a 2-hour lunch with the patient had also traveled in the same vehicle for a total of 30 minutes.

The authors said that the lack of secondary transmission may be "the nature of the community exposures to the case-patient compared with the more intimate and continuous exposures that would typically be experienced by household contacts."
May 29 Emerg Infect Dis study

News Scan for Jun 01, 2020

News brief

WHO touts growth of global antibiotic surveillance system

The World Health Organization (WHO) said today that a record number of countries are now monitoring and reporting data on antibiotic resistance but warned that the data reveal worrisome trends.

The WHO said its Global Antimicrobial Resistance and Use Surveillance System (GLASS), launched in 2015, now aggregates data from more than 64,000 surveillance sites in 66 countries. In 2018, the number of surveillance sites was 729 from 22 countries. In addition, more countries are reporting on the recently approved indicator on antimicrobial resistance as part of Sustainable Development monitoring.

GLASS data show that resistance to ciprofloxacin, an antibiotic commonly used to treat urinary tract infections, varied from 8.4% to 92.9% in 33 reporting countries.

"As we gather more evidence, we see more clearly and more worryingly how fast we are losing critically important antimicrobial medicines all over the world," Tedros Adhanom Ghebreyesus, PhD, director-general of the WHO, said in a press release. "These data underscore the importance both of protecting the antimicrobials we have and developing new ones, to effectively treat infections, preserve health gains made in the last century and ensure a secure future."

The WHO also expressed concern that antibiotic use in COVID-19 patients could exacerbate resistance trends. But the organization is hopeful that its recent guidance, which recommends against providing antibiotics to patients with mild COVID-19 or those with suspected or confirmed moderate COVID-19 unless there is clinical indication to do so, will help limit unnecessary use.
Jun 1 WHO press release

Data show antibiotic use in UK pigs leveling off after years of decline

New data from the United Kingdom's Agriculture and Horticulture Development Board (AHDB) show that total antibiotic use by UK pig farmers in 2019 was the same as it was in 2018.

The data, obtained from the electronic medicine book (eMB) and representing 95% of pigs slaughtered in the United Kingdom, show that 110 milligrams (mg) of antibiotics per population correction unit (PCU) were used in pigs in 2018 and 2019. From 2015 through 2018, antibiotic use in pigs fell from 278 mg/PCU to 110 mg/PCU, a drop of 60%.

But the use of highest-priority critically important antibiotics—those considered critical for treating bacterial infections in people—continued to fall, declining from 0.06 mg/PCU to 0.04 mg/PCU, and use of the last-resort antibiotic colistin fell from 0.004 mg/PCU to 0.002 mg/PCU.

AHDB officials say the levelling off is likely the result of a spike in swine dysentery cases in 2019. Swine dysentery is a bacterial disease frequently treated with antibiotics.

"It is disappointing that this may have prevented further reduction in our antibiotic use last year," AHDB Acting Head of Animal Health & Welfare, Mandy Nevel, PhD, said in a press release. "However, it is right that we put animal health and welfare first and, having discussed the results with the Pig Veterinary Society (PVS) and the wider industry, we can confirm that the consensus is the industry took the responsible approach and treated animals where necessary."
Jun 1 AHDB press release