Study finds low rate of mom-to-baby COVID-19 spread, effect on infants
Infants born to women with COVID-19 have a low chance of contracting the disease from their mothers and having complications, according to a study published yesterday in JAMA.
The study included 88,159 Swedish newborns, 92% of those born in the country from Mar 11, 2020, to Jan 31, 2021. Of those, 2,323 (1.6%) were delivered by mothers who tested positive for COVID-19, and only 21 infants in that group (0.9%) tested positive for COVID-19 themselves.
The mean gestational age among babies born to women with COVID was 39.2 weeks, compared with 39.6 weeks in the non-COVID group, and preterm birth rates were 8.8% versus 5.5%, respectively. Mortality was higher in infants who had mothers with COVID-19 (0.3% vs 0.12%), but the researchers say this difference is statistically insignificant, as is the length of hospital stay and breastfeeding rates.
In a matched cohort (infants from COVID-positive mothers with up to four infants from mothers without a positive COVID-19 diagnosis), infants in the maternal COVID-19 group were more likely to need neonatal care (11.7% vs 8.4%; odds ratio [OR], 1.47), or have respiratory distress syndrome (1.2% vs 0.5%; OR, 2.40), any neonatal respiratory disorder (2.8% vs 2.0%; OR, 1.42), or hyperbilirubinemia, which leads to jaundice (3.6% vs 2.5%; OR, 1.47).
“This study found support for preterm birth being an important mediator of the association between maternal SARS-CoV-2 and increased neonatal respiratory morbidity,” write the researchers, “whereas no statistically significant direct, infectious association with maternal SARS-CoV-2 could be demonstrated.”
Bias selection may have passed over women with asymptomatic COVID and homed in on women with more severe COVID-19 during testing decisions, note Dani Dumitriu, MD, PhD, and Cynthia Gyamfi-Bannerman, MD, in an editorial in the same journal. “Taken together with the lack of information on maternal illness severity and infection timing, the reported associations are likely to overestimate true neonatal morbidity,” they write.
“Our study suggests that mother and baby can be cared for together and that nursing can be recommended without danger to the baby’s health,” concluded first study author Mikael Norman, MD, in a Karolinska Institutet press release.
Apr 29 JAMA study & editorial
Apr 29 Karolinska Institutet press release
Report details rare injuries from nasopharyngeal COVID-19 swabbing
Risk of complication from COVID-19 nasopharyngeal swab tests is low (1.24 per 100,000 people), according to a research letter published yesterday in JAMA Otolaryngology-Head & Neck Surgery.
The researchers found 8 instances among 2,899 patients admitted to Helsinki University’s otorhinolaryngology emergency department from Mar 1 to Sep 30, 2020; 643,284 reverse transcription-polymerase chain reaction tests occurred during this time. Of the patients, seven were female, and mean age was 39.5 years. Four experienced severe nosebleeds, and four had broken swabs. None were positive for COVID-19.
Healthcare providers removed the broken swabs via nasal endoscopy and local anesthesia. The nasal bleeds, however, required treatment such as medication, nasal packing, or surgical and endovascular procedures. Outcomes of nosebleeds included one instance of sepsis, three local infections, and blood transfusions in three patients. Two of the nose bleeds resulted in life-threatening hemoglobin levels falling below 6.5 grams per deciliter.
“All complications seemed to involve an incorrect sampling technique: excess use of force or an overly cranial direction of the swab,” write the researchers. “Based on the results, the risk for a severe complication requiring specialist-level care after SARS-CoV-2 nasopharyngeal swab testing is extremely low.”
Apr 29 JAMA Otololaryngol Head Neck Surg study
Flu vaccine uptake increases after text reminders
Text message “nudges” before primary care visits may boost seasonal flu vaccine uptake more than 10%, a study yesterday in Proceedings of the National Academy of Sciences (PNAS) shows.
The finding was based on 47,306 patients in Penn Medicine and Geisinger Health systems who received 1 of 19 different possible nudges delivered to their mobile devices during the fall of 2020. The patients had opted in for text message from providers, and electronic health records showed they had not yet received a flu shot.
The patients were targeted via text before an upcoming medical appointment. The average age was 51, 43% were male, 70% were White, and 47% had been vaccinated in the previous flu season.
The authors said 6 out of 19 interventions (32%) produced a statistically significant boost in vaccinations. The top-performing nudges told patients a flu vaccine was reserved for them at an upcoming appointment and were delivered 72 and 24 hours before an appointment.
“The top-performing intervention in our study showed a 4.6 percentage point boost in vaccination (an 11% increase; P < 0.01) at the cost of sending two text messages (less than a dime),” the authors said. “Although the factors influencing the adoption of vaccines for other diseases, including COVID-19, differ in important ways, this successful script could potentially be repurposed.”
Apr 29 PNAS study
Madagascar, Liberia report first vaccine-derived polio cases
Nine countries reported polio cases this week, all involving vaccine-derived strains, including the first in Madagascar and Liberia, according to the latest update from the Global Polio Eradication Initiative (GPEI). Of countries reporting cases, seven are in Africa, and two are in the Middle East and central Asia.
In Africa, Madagascar reported 3 circulating vaccine-derived poliovirus type 1 (cVDPV1) cases, 2 in the South East region that are counted in 2020 totals and 1 in South West region that is the first of 2021. A listing of vaccine-derived polio cases from GPEI indicates that they are the country’s first such cases.
Meanwhile, Liberia reported its first circulating vaccine-derived poliovirus type 2 (cVDPV2) case, which involves a patient from Bong. Also, five countries in Africa reported more cVDPV2 cases: the Democratic Republic of the Congo (1), Mali (1), Nigeria (2), Sierra Leone (3), and South Sudan.
In the Middle East, Afghanistan reported 1 more cVDPV2 case, in a patient from Hirat, bringing the country’s total for the year to 33. And nearby Tajikistan reported one more such case, involving a person from Khatlon, lifting its total for 2021 to six.
Apr 29 GPEI update
GPEI table of circulating vaccine-derived polio cases