This week's roundup of some of the latest scientific studies on the novel coronavirus and efforts to find vaccines for COVID-19 shares promising results from trials about vaccine safety in pregnant women and the chronically ill and explores possible treatments for children with COVID-19.
Third-trimester vaccination appears safe in early data
Among pregnant women who received COVID-19 vaccines manufactured by Pfizer Inc. and BioNTech SE or Moderna Inc. and who signed up for an online survey, side effects were no different than what has been seen in the general population, researchers reported in The New England Journal of Medicine. But they noted that data of this nature is still sparse.
They looked at responses from smartphone users who participated in the U.S. Centers for Disease Control and Prevention (CDC) "v-safe" program, which collects information on COVID-19 vaccination experiences. Compared to non-pregnant women, the 35,691 pregnant responders reported more injection site pain but fewer headaches, muscle aches, chills and fevers. Among 3,958 women who signed up for a CDC pregnancy registry, no one vaccinated in the first trimester has given birth yet.
The Vaccine Adverse Event Reporting System (VAERS), run jointly by the CDC and the U.S. Food and Drug Administration (FDA), has recorded 46 miscarriages potentially related to COVID-19 vaccination, including 37 in the first trimester, the researchers said.
"Early data from the v-safe surveillance system, the v-safe pregnancy registry, and the VAERS do not indicate any obvious safety signals with respect to pregnancy or neonatal outcomes associated with COVID-19 vaccination in the third trimester of pregnancy," researchers concluded.
Pfizer-BioNTech vaccine effective in people with chronic illnesses
The Pfizer-BioNTech COVID-19 vaccine is effective at preventing symptomatic and severe disease in people with some chronic illnesses, like diabetes and heart disease, according to a large real-world study published in The New England Journal of Medicine.
The analysis of almost 1.4 million people, conducted by Clalit, Israel's largest health care provider, showed the vaccine was 80% effective against symptomatic infection for people with heart or chronic kidney diseases, 86% for people with Type 2 diabetes, 75% for cerebrovascular disease and 84% for people suffering from immunodeficiency.
For vaccinated people with at least three chronic conditions or risk factors, the vaccine was 88% effective in preventing symptomatic infection. It was more than 90% effective against severe disease for people with Type 2 diabetes, heart or cerebrovascular disease. The results were lower than the 95% overall vaccine effectiveness observed after the second dose in clinical trials last year.
"These results are very encouraging as they suggest that most COVID-19 cases will be prevented by vaccination even in the elderly and chronically ill," said Ran Balicer, Clalit's chief innovation officer.
Fever, shortness of breath are COVID-19 red flags in pregnancy
Pregnant women with COVID-19 and their newborns face "consistent and substantial increases" in risks of complications, an international study has found. COVID-19 in newborns is associated with a threefold risk of severe medical complications, according to a study conducted by scientists at the University of Oxford.
And pregnant women with symptomatic COVID-19 face higher risks of preterm delivery, preeclampsia (high blood pressure with organ failure risk), need for intensive care and death. That was particularly true for women with fever and shortness of breath, according to a report published on Friday in JAMA Pediatrics.
"Women with COVID-19 during pregnancy were over 50% more likely to experience pregnancy complications compared to pregnant women unaffected by COVID-19," said co-author Aris Papageorghiou. The study, conducted in 18 countries, included 706 pregnant women with COVID-19 and 1,424 similarly pregnant women without COVID-19 who were giving birth at the same hospital.
Findings also showed a delivery by Caesarean section may be associated with an increased risk of virus infection in newborns. Breastfeeding, however, does not seem to heighten risks of transmission from mothers to babies, they found.
Antiviral remdesivir appears safe for children
The antiviral drug remdesivir appears to be as safe and effective for use in children with COVID-19 as in adults, according to the largest study to date of children with severe COVID-19 who received the drug. Remdesivir, sold by Gilead Sciences Inc. under the brand name Veklury, shortens time to recovery in adults with COVID-19. It is not yet approved for children under age 12.
In March 2020, Gilead began accepting doctors' requests for compassionate use of remdesivir in critically ill children with COVID-19. In the new study of 77 children in the United States, U.K., Italy and Spain, "remdesivir was well tolerated, with a low incidence of serious adverse events," related to the drug, researchers reported in Pediatrics.
Within four weeks of starting treatment, 88% of the children had decreased need for oxygen support, 83% had recovered and 73% were discharged. Among those requiring mechanical ventilation, 90% were able to be taken off the ventilators. A randomized controlled trial is underway to confirm that the high level of recovery was due to the effects of remdesivir, the researchers said.
An editorial published with the study said: "Although morbidity and mortality rates differ, children hospitalized with acute COVID-19 often have a similar disease course as adults. Children are also likely to have a similar response to remdesivir as adults."