Study finds little menstrual cycle change after COVID vaccination
Despite anecdotal reports of alternations in menstrual cycle following COVID-19 vaccination, a study looking at the connection found little impact. A research team based at Oregon Health & Science University published their findings this week in Obstetrics & Gynecology.
The study was part of $1.67 million that the National Institutes of Health (NIH) put toward exploring the issue. Little is known about how vaccines against COVID-19 and other diseases impact the menstrual cycle.
For the study, researchers analyzed data from a fertility tracking app called Natural Cycles. For vaccinated women, researchers compared three consecutive cycles before vaccination with three more cycles after vaccination. The study included 3,959 women, 2,403 vaccinated and 1,556 unvaccinated. Most of the vaccinated women had received an mRNA vaccine.
Researchers found a 0.71 increase in cycle length associated with the first dose and a 0.91-day increase linked to the second dose. They saw no change in unvaccinated app users. Overall, users vaccinated over two cycles had an increased cycle length of less than a day, with no changes in the number of bleeding days.
The changes are well within normal menstrual cycle variability, the authors concluded.
In a NIH press release, Diana Bianchi, MD, with the NIH’s Eunice Kennedy Shriver National Institute of Child Health and Human Development, said finding that the changes were small and temporary was reassuring. “These results provide, for the first time, an opportunity to counsel women about what to expect from COVID-19 vaccination so they can plan accordingly,” she said.
Jan 5 Obstet Gynecol abstract
Jan 6 NIH press release
CDC tracks 3 rabies deaths in the United States linked to bats
The Centers for Disease Control and Prevention (CDC) said three people in the United States—including one child—died from rabies between September and November 2021. The deaths bring the total number of rabies fatalities in 2021 to five. No rabies deaths were reported in 2019 or 2020.
The three most recent fatalities, reported in Idaho, Illinois, and Texas, all were confirmed to have direct contact with bats in and around their homes. None of the three received postexposure prophylactic (PEP) shots, which can prevent death.
Bats are the most common route of human exposure to rabies in the United States: The CDC estimates that 60,000 people each year receive rabies PEP following animal exposures, and approximately two-thirds of these may be attributed to bats.
“We have come a long way in the United States towards reducing the number of people who become infected each year with rabies, but this recent spate of cases is a sobering reminder that contact with bats poses a real health risk,” said Ryan Wallace, DVM, MPH, a veterinarian and rabies expert in the CDC’s Division of High-Consequence Pathogens and Pathology in a press release on the cases.
Jan 7 CDC press release
Jan 7 Morbidity and Mortality Weekly Report note
Study describes outbreak of highly resistant, deadly Klebsiella in India
Indian researchers yesterday reported on a hospital outbreak of two strains of extensively drug-resistant Klebsiella pneumoniae. Their findings appeared in Antimicrobial Resistance and Infection Control.
The outbreak in the tertiary care hospital in Varanasi, India, was first identified between April and June, 2017, when a sudden surge of neonatal sepsis cases caused by K pneumoniae occurred in the hospital’s neonatal intensive care unit (NICU); twelve of the 14 infants died. Subsequent environmental surveillance uncovered K pneumoniae in the hand-wash used in the NICU, and in the wash basin in the labor room. Further investigation revealed an adult infected with K pneumonia on Apr 3 in the intensive care unit (ICU) was the hospital’s primary case. An additional 18 K pneumoniae infections were reported in the ICU until July 2017.
Analysis of 45 K pneumoniae isolates from the ICU, NICU, other wards, and the hospital environment found all of the NICU isolates and 94.4% of the ICU isolates were resistant to all tested antibiotics, including colistin and carbapenems. More than half of the isolates carried a combination of extended-spectrum beta-lactamase and carbapenemase genes. Clonal typing found two distinct sequence types, ST5235 and ST5313, with ST5235 predominantly found in the NICU.
The outbreak was contained through strengthening of infection control procedures and an unrelated hospital closure. No further cases were identified after Jul 6, 2017.
The study authors say the findings highlight concerns about the rising use of colistin and poor infection control measures in Indian hospitals, and call for the global impact of ST5235 and ST5315 to be further studied.
Jan 6 Antimicrob Resist Infect Control study