COVID-19: Top science stories of the week, from hydroxychloroquine doubts to children’s resilience

Friday 5 June update: This study was retracted from the Lancet on Thursday 4 June. For the latest see here.

A study published in the Lancet has found that antimalarial drug hydroxychloroquine offers no benefit as a treatment for COVID-19 in hospitalised patients and is instead linked to an elevated risk of death and disordered heartbeats.

The research, led by Dr. Mandeep Mehra, medical director of the Brigham and Women’s Hospital Heart and Vascular Centre, analysed data from almost 100,000 patients around the world with COVID-19. Some 15,000 patients were treated with hydroxychloroquine or the related drug chloroquine either alone or in combination with antibiotics. The health outcomes of these groups were compared with 81,000 patients who did not receive either drug. The study found that patients receiving hydroxychloroquine or chloroquine with or without antibiotics were more likely to die in hospital or develop abnormal heart rhythms.

In response the World Health Organization has temporarily paused all its trials involving hydroxychloroquine while its data safety monitoring board performs a review.

On Thursday The Guardian reported that Australian researchers have queried the origin of some of the data used in the Lancet study after finding they mistakenly included patients from an Asian hospital in the Australasian part of the dataset. They claim that this discrepancy should not change the overall findings of the study, but the Lancet has asked the authors for clarification and will provide an update when more information is available.

As of today, more than 120 researchers and medical professionals from around the world have written an open letter to the editor of the Lancet raising serious concerns about the study.

In a study that is yet to be peer reviewed, children and adolescents were found to be 56% less likely to become infected by the virus that causes COVID-19 than over-20s when in contact with an infected person.

The meta-analysis, led by Prof. Russell Viner at University College London’s Great Ormond Street Institute of Child Health, reviewed more than 6,000 COVID-19 papers before identifying 18 that contained useful information on the susceptibility of children to infection. Of these, seven had been subject to peer review. The researchers acknowledged the mixed quality of studies included in their analysis, stating: “we elected to include all [18] studies regardless of quality due to the very high policy relevance of findings, however this limits our ability to make stronger conclusions."

Their findings suggest that children may have played a smaller role than adults in spreading the virus due to being less likely to become infected. There has not yet been enough research to determine whether, once infected, children are less likely to pass on the virus.

Relatively little is known about how symptomatic and asymptomatic COVID-19 infections differ in their affect on the body. On Wednesday, a small peer-reviewed study of patients admitted to Wuhan University’s Zhongnan Hospital with COVID-19 shed some light on this.

A total of 78 patients were studied, of which 33 were asymptomatic while 45 were symptomatic. Asymptomatic patients were found to:

Further studies are needed to confirm and expand these findings but the researchers highlighted the finding of higher lymphocyte counts in patients who do not display symptoms indicate less damage having been done to patients’ immune systems compared to symptomatic cases. They also noted the duration of viral shedding in asymptomatic patients underscores the importance of identifying and isolating people who are not showing symptoms to prevent further transmission.