Healthcare workers' SARS-CoV-2 infection rates during the second wave of the pandemic: follow-up study

OBJECTIVES

This study aimed to assess if, during the second wave of the COVID-19 pandemic, healthcare workers had increased severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection rates, following close contact with patients, co-workers and persons outside work with COVID-19.

METHODS

A follow-up study of 5985 healthcare workers from Denmark was conducted between November 2020 and April 2021 and provided day-to-day information on COVID-19 contacts. SARS-CoV-2 infection was defined by the first positive polymerase chain reaction (PCR) test ever. Data was analyzed in multivariable Poisson regression models.

RESULTS

The SARS-CoV-2 infection rates following close contact 3-7 days earlier with patients, co-workers and persons outside work with COVID-19 were 153.7, 240.8, and 728.1 per 100 000 person-days, respectively. This corresponded with age, sex, month, number of PCR tests and mutually adjusted incidence rate ratios of 3.17 [40 cases, 95% confidence interval (CI) 2.15-4.66], 2.54 (10 cases, 95% CI 1.30-4.96) and 17.79 (35 cases, 95% CI 12.05-26.28). The risk of SARS-CoV-2 infection was thus lower, but the absolute numbers affected was higher following COVID-19 contact at work than COVID-19 contact off work.

CONCLUSIONS

Despite strong focus on preventive measures during the second wave of the pandemic, healthcare workers were still at increased risk of SARS-CoV-2 infection when in close contact with patients or co-workers with COVID-19. There is a need for increased focus on infection control measures in order to secure healthcare workers' health and reduce transmission into the community during ongoing and future waves of SARS-CoV-2 and other infections.

P–617 Idiopathic early ovarian aging: Do biomarkers of ageing indicate premenopausal accelerated biological ageing in young women with diminished response to ART?

Study question

Do young women with idiopathic early ovarian ageing have changes in telomere length and epigenetic age indicating accelerated biological aging?

Summary answer

The telomere length and epigenetic age were comparable to those in young women with normal ovarian ageing.

What is known already

Increased risk of several health events usually considered to be age-related such as cardiovascular disease, osteoporosis, over-all morbidity and mortality have been associated with premature and early menopause when compared to the risk in women with normal menopausal age suggesting an accelerated general ageing process associated to early ovarian ageing. It is unclear whether the onset of this process may start before menopause.

Study design, size, duration

A prospective cohort study. Young women (≤ 37 years) having ART at two Danish Public fertility clinics during the period 2016 to 2018 were divided into two groups dependent on their ovarian reserve status: early ovarian ageing (EOA) (N = 55) and normal ovarian ageing (NOA)( N = 52). Number of oocytes harvested in first and subsequent cycles was used as a marker of ovarian reserve. Blood samples was drawn at time of oocyte retrieval to assess biological age.

Participants/materials, setting, methods

EOA was defined as ≥ 2 IVF cycles with ≤ 5 harvested oocytes despite sufficient stimulation with FSH and NOA as ≥ 8 oocytes harvested in minimum 1 cycle. Known causes influencing the ovarian reserve (endometriosis, ovarian surgery, etc.) was reason for exclusion. Relative telomere length (qPCR) and epigenetic age acceleration (DNA methylation levels) were measured in white blood cells as markers of accelerated biological ageing.

Main results and the role of chance

Relative telomere length was comparable with a mean of 0.46 (± sd 0.12) in the EOA group and 0.47 (0.14) in the normal ovarian ageing group (p = 0.64). The difference of predicted mean epigenetic age and mean chronological age (i.e. epigenetic age acceleration) was, insignificantly, 0.5 years older in the EOA group when compared to the NOA group( (–1.02 years (2.62) and –1.57 years (2.56), respectively, p = 0.27)), but this difference disappeared when adjusting for chronological age.

Limitations, reasons for caution

Discrete changes in epigenetic age acceleration may not have been captured as the study only had power to detect an age acceleration of ≥ 2 years.

Wider implications of the findings: By analysis of biomarkers for ageing in whole blood, we did not find any indications of a premenopausal accelerated aging in young women with idiopathic EOA. Further investigations in a similar cohort of premenopausal women is needed to fully elucidate the potential relationship between premenopausal accelerated biological ageing and EOA.

Trial registration number

The study was approved by the Danish Data protection Agency (nr 1–16–02–320–14) and the Regional committee on health research ethics of Central Region Denmark (jr.no 1–10–72–142–14).

Early ovarian ageing: is a low number of oocytes harvested in young women associated with an earlier and increased risk of age-related diseases?

STUDY QUESTION

Do young women with early ovarian ageing (EOA), defined as unexplained, and repeatedly few oocytes harvested in ART have an increased risk of age-related events?

SUMMARY ANSWER

At follow-up, women with idiopathic EOA had an increased risk of age-related events compared to women with normal ovarian ageing (NOA).

WHAT IS KNOWN ALREADY

Early and premature menopause is associated with an increased risk of cardiovascular diseases (CVDs), osteoporosis and death. In young women, repeated harvest of few oocytes in well-stimulated ART cycles is a likely predictor of advanced menopausal age and may thus serve as an early marker of accelerated general ageing.

STUDY DESIGN, SIZE, DURATION

A register-based national, historical cohort study. Young women (≤37 years) having their first ART treatment in a public or private fertility clinic during the period 1995-2014 were divided into two groups depending on ovarian reserve status: EOA (n = 1222) and NOA (n = 16 385). Several national registers were applied to assess morbidity and mortality.

PARTICIPANTS/MATERIALS, SETTING, METHODS

EOA was defined as ≤5 oocytes harvested in a minimum of two FSH-stimulated cycles and NOA as ≥8 oocytes in at least one cycle. Cases with known causes influencing the ovarian reserve (endometriosis, ovarian surgery, polycystic ovary syndrome, chemotherapy etc.) were excluded. To investigate for early signs of ageing, primary outcome was an overall risk of ageing-related events, defined as a diagnosis of either CVD, osteoporosis, type 2 diabetes, cancer, cataract, Alzheimer's or Parkinson's disease, by death of any-cause as well as a Charlson comorbidity index score of ≥1 or by registration of early retirement benefit. Cox regression models were used to assess the risk of these events. Exposure status was defined 1 year after the first ART cycle to assure reliable classification, and time-to-event was measured from that time point.

MAIN RESULTS AND THE ROLE OF CHANCE

Median follow-up time from baseline to first event was 4.9 years (10/90 percentile 0.7/11.8) and 6.4 years (1.1/13.3) in the EOA and NOA group, respectively. Women with EOA had an increased risk of ageing-related events when compared to women with a normal oocyte yield (adjusted hazard ratio 1.24, 95% CI 1.08 to 1.43). Stratifying on categories, the EOA group had a significantly increased risk for CVD (1.44, 1.19 to 1.75) and osteoporosis (2.45, 1.59 to 3.90). Charlson comorbidity index (1.15, 0.93 to 1.41) and early retirement benefit (1.21, 0.80 to 1.83) was also increased, although not reaching statistical significance.

LIMITATIONS, REASONS FOR CAUTION

Cycles never reaching oocyte aspiration were left out of account in the inclusion process and we may therefore have missed women with the most severe forms of EOA. We had no information on the total doses of gonadotrophin administered in each cycle.

WIDER IMPLICATIONS OF THE FINDINGS

These findings indicate that oocyte yield may serve as marker of later accelerated ageing when, unexpectedly, repeatedly few oocytes are harvested in young women. Counselling on life-style factors as a prophylactic effort against cardiovascular and other age-related diseases may be essential for this group of women.

STUDY FUNDING/COMPETING INTEREST(S)

No external funding was received for this study. All authors declare no conflict of interest.

TRIAL REGISTRATION NUMBER

N/A.

Effect of mutations in Candida antarctica B lipase

Three variants of the Candida antarctica B lipase have been constructed and characterized. The variant containing the T103G mutation, which introduces the consensus sequence G-X-S-X-G found in most other known lipases, shows an increased thermostability but retains only half the specific activity of the native enzyme. Also in ester synthesis the activity is lowered but the specificity and enantioselectivity remains unchanged. The W104H mutant, in which more space is introduced into the active site, has more dramatically changed properties. Both the thermostability and the specific activity are slightly reduced but the activity and specificity in ester synthesis is highly different from the native enzyme. In general, the activity is very low and the enantioselectivity is, furthermore, highly reduced. Finally, the mutation M72L was introduced to increase the oxidation stability of the enzyme. This variant did exhibit an increased resistance towards oxidation but the thermostability was, unfortunately, also reduced.

Bilateral fetal chylothorax: results of unilateral in utero therapy

The optimal method for antenatal treatment of pleural effusions from congenital chylothorax unknown. A fetus with bilateral congenital chylothorax and hydrops had a pleural catheter placed in utero on only one side of the fetal chest for 14 days prior to delivery. The fetal hydrops partially resolved. After birth there was significantly less drainage from the pleural space that had been antenatally drained. This case demonstrates potential neonatal advantages of pleuro-amniotic shunt placement.

Cord-containing amniotic fluid pocket: a useful measurement in the management of oligohydramnios

OBJECTIVE

To test the hypothesis that among patients with a low amniotic fluid (AF) index, those who have a large cord-containing AF pocket will have a lower risk for adverse perinatal outcome than women with a small cord-containing pocket.

METHODS

Gravidas with an antepartum AF index no greater than 5 cm were studied prospectively. The vertical diameter of the single largest cord-containing pocket, which was excluded from the calculation of the AF index, was measured. Women with rupture of the membranes, multiple gestation, or fetal anomalies were excluded.

RESULTS

Fifty-one women with gestational ages of 35-43 weeks were analyzed. Among 35 who had a cord-containing pocket of no more than 5 cm, eight (23%) had fetal distress necessitating operative delivery and eight neonates had cord arterial pH below 7.20. None of these complications occurred in the 16 women who had a cord-containing pocket above 5 cm (P < .05). The mean AF index (2.9 versus 2.8 cm) was not significantly different between the groups.

CONCLUSION

Among women with a low AF index, a cord-containing pocket above 5 cm identifies a subgroup of women at lower perinatal risk compared with those with a smaller cord-containing pocket. The need for intervention may be reduced in women with a cord-containing pocket greater than 5 cm.