COVID-19

COVID-19 Roundup: Vaccine Updates, Viral Load in Children, Hearing Loss

3 Vaccines Show Potential

Two doses of a vaccine co-developed by the National Institute of Allergy and Infectious Disease Vaccine Research Center and at Moderna, Inc., Cambridge, Massachusetts “induced robust immune responses and rapidly controlled the coronavirus in the upper and lower airways of rhesus macaques exposed to SARS-CoV-2,” according to a new report. Of note, those primates who received the vaccine produced levels of antibodies significantly higher than those observed in humans who have recovered from COVID-19.1

AstraZeneca has said “so far, so good” regarding their experimental vaccine which is already in large human trials. “The vaccine development is progressing well. We have had good data so far. We need to show the efficacy in the clinical program, but so far, so good,” said Chief Executive Pascal Soriot.2

Johnson & Johnson reported that a single dose of their experimental vaccine “elicited a robust immune response” in non-human primates during a pre-clinical study. Based on these results, a Phase 1/2a first-in-human trial of healthy volunteers has begun in the US and Belgium.3 

Viral Loads in Children4

A study published in JAMA Pediatrics has found that children younger than 5 years old exposed to the virus have as much as 100 times more SARS-CoV-2 RNA in their upper respiratory tracts than do older children and adults. The researchers noted that their study was limited to the detection of viral nucleic acid and not infectious virus, but that previous studies have linked higher levels of nucleic acid with the ability to culture infectious virus.

“Thus, young children can potentially be important drivers of SARS-CoV-2 spread in the general population, as has been demonstrated with respiratory syncytial virus, where children with high viral loads are more likely to transmit,” they concluded.

Hearing Changes During Recovery5

In a letter to the International Journal of Audiology, researchers described the results of a telephone survey of 121 adults who had been admitted to the Hospital with COVID-19 infection. Of the 121, 16 (13.2%) reported hearing changes since discharge from the hospital (8 reporting hearing deterioration and 8 reporting tinnitus).

The researchers cautioned, however, that other factors could be associated with these changes.

“That is why we believe there is an urgent need for high-quality studies to investigate the acute and temporary effects of COVID-19 on hearing and the audiovestibular system,” they concluded.

—Michael Potts

References:

  1. Experimental COVID-19 vaccine protects upper and lower airways in nonhuman primates. News release. Bethesda, MD; National Institute of Allergy and Infectious Disease: July 28, 2020. https://www.nih.gov/news-events/news-releases/experimental-covid-19-vaccine-protects-upper-lower-airways-nonhuman-primates
  2. 'So far, so good' on leading COVID vaccine, says AstraZeneca. News release. Reuters; July 30, 2020. https://www.reuters.com/article/us-astrazeneca-results-idUSKCN24V0SH
  3. Single dose of Johnson & Johnson COVID-19 vaccine candidate demonstrates robust protection in pre-clinical studies. News release. New Brunswick, NJ. Johnson & Johnson: July 30, 2020.
  4. Heald-Sargent T, Muller WJ, Zheng X, et al. Age-related differences in nasopharyngeal severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) levels in patients with mild to moderate coronavirus disease 2019 (COVID-19). Published online July 30, 2020. JAMA Pediatr. doi:10.1001/jamapediatrics.2020.3651
  5. Hearing deterioration reported by discharged COVID-19 patients. News release. Manchester, UK: University of Manchester; July 31, 2020.