Impact of Intrapartum Azithromycin on the Carriage and Antibiotic Resistance of Escherichia coli and Klebsiella pneumoniae in Mothers and their Newborns: a sub-study of a Randomized Double-Blind Trial Conducted in The Gambia and Burkina Faso.

BACKGROUND: Limited data exists on effects of intrapartum azithromycin on prevalence of carriage and antibiotic resistance of Enterobacterales. METHODS: We conducted a randomized trial in Gambia and Burkina Faso where women received intrapartum azithromycin (2g) or placebo. We determined impact of treatment on prevalence of carriage and antibiotic resistance of Escherichia coli and Klebsiella pneumoniae by analysing rectal swabs (RS), nasopharyngeal swabs (NPS), breast milk and recto-vaginal swabs (RVS). Bacteria were isolated microbiologically; antibiotic susceptibility was confirmed with an E-test. Prevalence ratios (PR) with 95% confidence intervals (CI's) were used for comparison between arms. RESULTS: In infants, E. coli carriage in RS was lower in the intervention than placebo arm at days 6 (63.0% vs. 75.2%, PR, 0.84; CI, 0.75-0.95) and 28 (52.7% vs. 70.4%, 0.75; 0.64-0.87) post-intervention. Prevalence of azithromycin-resistant E. coli was higher in the azithromycin arm at days 6 (13.4% vs. 3.6%, 3.75; 1.83-7.69) and 28 (16.4% vs. 9.6%, 1.71; 1.05-2.79). For K. pneumoniae, carriage in RS was higher in the intervention than placebo arm at days 6 (49.6% vs. 37.2%, 1.33; 1.08-1.64) and 28 (53.6% vs. 32.9%, 1.63; 1.31-2.03). Prevalence of azithromycin-resistant K. pneumoniae was higher in the azithromycin arm at day 28 (7.3% vs. 2.1%, 3.49; 1.30-9.37). No differences were observed for other sample types. CONCLUSION: Intrapartum azithromycin decreased E. coli carriage but increased both K. pneumoniae carriage and azithromycin resistance in both bacteria. These data need to be considered together with efficacy results to balance the potential short- and long-term impact of the intervention. CLINICAL TRIALS REGISTRATION: www.clinicaltrials.gov: NCT03199547.

Genomic approach to determine sources of neonatal Staphylococcus aureus infection from carriage in the Gambia.

Staphylococcus aureus is a major cause of neonatal infections in various anatomical sites, resulting in high morbidity and mortality in The Gambia. These clinical infections are often preceded by nasal carriage of S. aureus, a known risk factor. To determine whether potential sources of newborn S. aureus infections were from carriage, and to characterize S. aureus present in different anatomical sites (blood, ear, eye, umbilical cord, skin, pus, oropharynx, breast milk and vagina), we performed whole-genome sequencing of 172 isolates from clinical sites as well as from healthy and unhealthy carriage. A random selection of mothers (n = 90) and newborns (n = 42) participating in a clinical trial and testing positive for S. aureus were considered for this study. Sequence data were analyzed to determine S. aureus multilocus sequence types and selected antimicrobial and virulence gene profiles. Our findings revealed that in The Gambia, ST15 is the dominant sequence type associated with both carriage and clinical infection. In addition, S. aureus isolates causing clinical infection among neonates were genetically similar to those colonizing their oropharynx, and the different anatomical sites were not found to be uniquely colonized by S. aureus of a single genomic profile. Furthermore, while S. aureus associated with clinical infection had similar antimicrobial resistance gene profiles to carriage isolates, only hemolysin and adhesive factor virulence genes were significantly higher among clinical isolates. In conclusion, this study confirmed S. aureus oropharyngeal colonization among neonates as a potential source of clinical infection in The Gambia. Hence, interventions aiming to reduce neonatal clinical infections in The Gambia should consider decreasing oropharyngeal S. aureus carriage.Trial registration The trial was registered at ClinicalTrials.gov NCT03199547.

Effect of Intrapartum Azithromycin vs Placebo on Neonatal Sepsis and Death: A Randomized Clinical Trial.

Importance: Neonatal sepsis is a leading cause of neonatal mortality. New interventions are needed to decrease neonatal sepsis and mortality in regions with highest burden. Objective: To evaluate the efficacy of intrapartum azithromycin to reduce neonatal sepsis or mortality, as well as neonatal and maternal infections. Design, Setting, and Participants: This double-blind, placebo-controlled, randomized clinical trial enrolled and followed up birthing parents and their infants at 10 health facilities in The Gambia and Burkina Faso, West Africa, between October 2017 and May 2021. Interventions: Participants were assigned at random to receive oral azithromycin (2 g) or placebo (ratio 1:1) during labor. Main Outcomes and Measures: The primary outcome was a composite of neonatal sepsis or mortality, with the former defined based on microbiologic or clinical criteria. Secondary outcomes were neonatal infections (skin, umbilical, eye and ear infections), malaria, and fever; postpartum infections (puerperal sepsis, mastitis), fever, and malaria; and use of antibiotics during 4-week follow-up. Results: The trial randomized 11 983 persons in labor (median age, 29.9 years). Overall, 225 newborns (1.9% of 11 783 live births) met the primary end point. The incidence of neonatal mortality or sepsis was similar in the azithromycin and placebo groups (2.0% [115/5889] vs 1.9% [110/5894]; risk difference [RD], 0.09 [95% CI, -0.39 to 0.57]), as was the incidence of neonatal mortality (0.8% vs 0.8%; RD, 0.04 [95% CI, -0.27 to 0.35]) and neonatal sepsis (1.3% vs 1.3%; RD, 0.02 [95% CI, -0.38 to 0.43]). Newborns in the azithromycin group compared with the placebo group had lower incidence of skin infections (0.8% vs 1.7%; RD, -0.90 [95% CI, -1.30 to -0.49]) and need for antibiotics (6.2% vs 7.8%; RD, -1.58 [95% CI, -2.49 to -0.67]). Postpartum parents in the azithromycin group had lower incidence of mastitis (0.3% vs 0.5%; RD, -0.24 [95% CI, -0.47 to -0.01]) and puerperal fever (0.1% vs 0.3%; RD, -0.19 [95% CI, -0.36 to -0.01]). Conclusions and Relevance: Azithromycin administered orally during labor did not reduce neonatal sepsis or mortality. These results do not support routine introduction of oral intrapartum azithromycin for this purpose. Trial Registration: ClinicalTrials.gov Identifier: NCT03199547.

Impact of intra-partum azithromycin on carriage of group A streptococcus in the Gambia: a posthoc analysis of a double-blind randomized placebo-controlled trial.

BACKGROUND: Group A Streptococcus (GAS) is a major human pathogen and an important cause of maternal and neonatal sepsis. Asymptomatic bacterial colonization is considered a necessary step towards sepsis. Intra-partum azithromycin may reduce GAS carriage. METHODS: A posthoc analysis of a double-blind, placebo-controlled randomized-trial was performed to determine the impact of 2 g oral dose of intra-partum azithromycin on maternal and neonatal GAS carriage and antibiotic resistance. Following screening, 829 mothers were randomized who delivered 843 babies. GAS was determined by obtaining samples from the maternal and newborn nasopharynx, maternal vaginal tract and breastmilk. Whole Genome Sequencing (WGS) of GAS isolates was performed using the Illumina Miseq platform. RESULTS: GAS carriage was lower in the nasopharynx of both mothers and babies and breast milk among participants in the azithromycin arm. No differences in GAS carriage were found between groups in the vaginal tract. The occurrence of azithromycin-resistant GAS was similar in both arms, except for a higher prevalence in the vaginal tract among women in the azithromycin arm. WGS revealed all macrolide-resistant vaginal tract isolates from the azithromycin arm were Streptococcus dysgalactiae subspecies equisimilis expressing Lancefield group A carbohydrate (SDSE(A)) harbouring macrolide resistant genes msr(D) and mef(A). Ten of the 45 GAS isolates (22.2%) were SDSE(A). CONCLUSIONS: Oral intra-partum azithromycin reduced GAS carriage among Gambian mothers and neonates however carriage in the maternal vaginal tract was not affected by the intervention due to azithromycin resistant SDSE(A). SDSE(A) resistance must be closely monitored to fully assess the public health impact of intrapartum azithromycin on GAS. Trial registration ClinicalTrials.gov Identifier NCT01800942.

Impact of Intrapartum Oral Azithromycin on the Acquired Macrolide Resistome of Infants' Nasopharynx: A Randomized Controlled Trial.

In a post hoc analysis of samples from an intrapartum azithromycin randomized clinical trial, we found that children whose mothers had been treated with the drug had higher prevalence of macrolide-resistance genes msr(A) and ermC at 28 days but not at 12 months. The 2 genes were positively associated in the nasopharynx. CLINICAL TRIALS REGISTRATION: NCT1800942.

Long-term Impact of Oral Azithromycin Taken by Gambian Women During Labor on Prevalence and Antibiotic Susceptibility of Streptococcus pneumoniae and Staphylococcus aureus in Their Infants: Follow-up of a Randomized Clinical Trial.

Background: Oral azithromycin given to women in labor decreases maternal and neonatal bacterial carriage but increases azithromycin-resistant bacteria during at least 4 weeks following the intervention. We assessed the prevalence of bacterial carriage and azithromycin resistance 12 months after treatment among study infants. Methods: Nasopharyngeal swabs (NPSs) were collected between November 2014 and May 2015 from children aged 11-13 months whose mothers had received azithromycin or placebo during labor. Streptococcus pneumoniae and Staphylococcus aureus were isolated using conventional microbiological methods. Antibiotic susceptibility was determined by disk diffusion and confirmed by Etest or VITEK-2. Results: NPSs were collected from 461 children. The prevalence of S. pneumoniae and S. aureus was similar between children from the azithromycin and placebo arms (85.0% vs 82.1%; odds ratio [OR], 1.23 [95% confidence interval {CI}, .73-2.08] for S. pneumoniae and 21.7% vs 21.3%; OR, 1.02 [95% CI, .64-1.64] for S. aureus). Prevalence of azithromycin-resistant S. pneumoniae was similar in both arms (1.8% vs 0.9% in children from the azithromycin and placebo arms, respectively; OR, 2.10 [95% CI, .30-23.38]); resistance to other antibiotics was also similar between arms. For S. aureus, there was no difference in azithromycin resistance between children in the azithromycin (3.1%) and placebo (2.6%) arms (OR, 1.22 [95% CI, .35-4.47]) or resistance to any other antibiotics. Conclusions: The higher prevalence of S. aureus azithromycin resistance observed among women treated during labor and their babies 4 weeks after treatment had waned 12 months after delivery. Azithromycin intervention did not induce other antibiotic resistance to S. pneumoniae or S. aureus. Clinical Trials Registration: NCT01800942.

Does azithromycin given to women in labour decrease ocular bacterial infection in neonates? A double-blind, randomized trial.

BACKGROUND: Vertical transmission can result in neonatal infection and disease. Reducing the transmission of bacterial pathogens from mother to infant may be an effective means of preventing neonatal infection, including bacterial conjunctivitis. METHODS: In a double-blind, randomized trial, we assessed the effect of administering a single dose of oral azithromycin to women in labour on bacterial colonization of the neonate. A reduction in purulent neonatal conjunctivitis was a secondary objective of the trial. Ocular samples were collected from the lower fornix of infants presenting with clinical signs of purulent conjunctivitis during the first eight weeks of life. Incidence of purulent conjunctivitis was compared between trial arms. Bacterial infection was assessed using PCR and incidence of purulent conjunctivitis due to bacteria was also compared between arms. RESULTS: Forty of 843 infants (4.7%) presented clinical signs of purulent conjunctivitis. No significant difference in incidence of purulent conjunctivitis was seen between azithromycin and placebo arms [4.3% (18/419) versus 5.2% (22/424), OR = 0.82, 95% CI (0.44,1.54), p = 0.628]. S. aureus was the most commonly identified pathogen, detected in 38% of cases. Incidence of purulent-conjunctivitis due to bacterial infection was lower in the azithromycin arm [1.2% (5/419) versus 3.8% (16/424), OR = 0.31, 95% CI (0.12-0.82), p = 0.025)]. The incidence of gram-positive bacteria was also lower in the azithromycin arm [1.0% (4/419) versus 3.3% (14/424), OR = 0.28, 95%CI (0.10-0.82), p = 0.029]. CONCLUSIONS: Oral azithromycin given to women during labour may have the potential to reduce the incidence of bacterial neonatal conjunctivitis. TRIAL REGISTRATION: ClinicalTrials.gov, identifier NCT01800942 , registration date 26 Feb 2013.

Pharmacokinetics of Transfer of Azithromycin into the Breast Milk of African Mothers.

Azithromycin (AZI) is used for its antibiotic and antimalarial properties in pregnancy. Reported estimates of AZI breast milk transfer, based on concentrations in mostly single samples from small numbers of women, have suggested that infant intake is safe. To better characterize infant intake and the associated potential benefits and risks, AZI was measured by liquid chromatography-mass spectrometry in four breast milk samples taken over 28 days postpartum from each of 20 Gambian women given 2 g AZI during labor. A population pharmacokinetic model utilizing published parameters for AZI disposition in pregnancy, the present breast milk concentrations, and increasing/decreasing sigmoid maximum-effect (Emax) functions adequately described temporal changes in the milk/plasma ratio. The median estimated absolute and relative cumulative infant doses were 4.5 mg/kg of body weight (95% prediction interval, 0.6 to 7.0 mg/kg) and 15.7% (95% prediction interval, 2.0 to 27.8%) of the maternal dose, respectively; the latter exceeded the recommended 10% safety limit. Although some infants with bacterial infections may benefit from AZI in breast milk, there is a risk of hypertrophic pyloric stenosis with a worst-case number needed to harm of 60 based on the present and available epidemiologic data. (This study has been registered at ClinicalTrials.gov under registration no. NCT01800942.).

Prevention of bacterial infections in the newborn by pre-delivery administration of azithromycin: Study protocol of a randomized efficacy trial.

BACKGROUND: Neonatal deaths, estimated at approximately 4 million annually, now account for almost 40% of global mortality in children aged under-five. Bacterial sepsis is a leading cause of neonatal mortality. Assuming the mother is the main source for bacterial transmission to newborns, the primary objective of the trial is to determine the impact of one oral dose of azithromycin, given to women in labour, on the newborn's bacterial carriage in the nasopharynx. Secondary objectives include the impact of the intervention on bacterial colonization in the baby and the mother during the first month of life. METHODS/DESIGN: This is a Phase III, double -blind, placebo controlled randomized clinical trial in which 830 women in labour were randomized to either a single dose of 2 g oral azithromycin or placebo (ratio 1:1). The trial included pregnant women in labour aged 18 to 45 years attending study health centres in the Western Gambia. A post-natal check of the mother and baby was conducted at the health centre by study clinicians before discharge and 8-10 days after delivery. Home follow up visits were conducted daily during the first week and then weekly until week 8 after delivery. Vaginal swabs and breast milk samples were collected from the mothers, and the pathogens Streptococcus pneumoniae, Group B Streptococcus (GBS) and Staphylococcus aureus were isolated from the study samples. For bacterial isolates, susceptibility pattern to azithromycin was determined using disk diffusion and E-test. Eye swabs were collected from newborns with eye discharge during the follow up period, and Chlamydial infection was assessed using molecular methods. DISCUSSION: This is a proof-of-concept study to assess the impact of antibiotic preventive treatment of women during labour on bacterial infections in the newborn. If the trial confirms this hypothesis, the next step will be to assess the impact of this intervention on neonatal sepsis. The proposed intervention should be easily implementable in developing countries. TRIAL REGISTRATION: ClinicalTrials.gov Identifier--NCT01800942--First received: February 26, 2013.

Effect of intrapartum azithromycin on gut microbiota development in early childhood: A post hoc analysis of a double-blind randomized trial.

Intrapartum azithromycin prophylaxis has shown the potential to reduce maternal infections but showed no effect on neonatal sepsis and mortality. Antibiotic exposure early in life may affect gut microbiota development, leading to undesired consequences. Therefore, we here assessed the impact of 2 g oral intrapartum azithromycin on gut microbiota development from birth to the age of 3 years, by 16S-rRNA gene profiling of rectal samples from 127 healthy Gambian infants selected from a double-blind randomized placebo-controlled clinical trial (PregnAnZI-2). Microbiota trajectories showed, over the first month of life, a slower community transition and increase of Enterobacteriaceae (p = 0.001) and Enterococcaceae (p = 0.064) and a decrease of Bifidobacterium (p < 0.001) in the azithromycin compared to the placebo arm. Intrapartum azithromycin alters gut microbiota development and increases proinflammatory bacteria in the first month of life, which may have undesirable effects on the child.

Short-term increase in the carriage of azithromycin-resistant Escherichia coli and Klebsiella pneumoniae in mothers and their newborns following intra-partum azithromycin: a post hoc analysis of a double-blind randomized trial.

OBJECTIVES: To evaluate the impact of one oral dose of intrapartum azithromycin (2 g) on the carriage and antibiotic resistance of Escherichia coli and Klebsiella pneumoniae in the nasopharynx, breast milk and vaginal swabs of mothers and K. pneumoniae in the nasopharynx of their newborns. METHODS: We performed a post hoc analysis of a double-blind, placebo-controlled randomized-trial (ratio 1:1) conducted in The Gambia. Breast milk (BM) and vaginal swabs (VS) from mothers and nasopharyngeal swabs (NPS) from mother-newborn pairs were collected at different timepoints during the 4 week follow-up. Samples were processed using standard microbiological procedures. For BM and NPS post-intervention results were combined for analysis. RESULTS: In the original trial 829 mothers were randomized. In this analysis, complete sample sets were available for 630 mothers for E. coli analysis (76.0%) and 564 mother-newborn pairs for K. pneumoniae analysis (68.0%). For E. coli, carriage prevalence in BM and VS was similar in both arms but resistance was higher in the azithromycin arm in VS (2.6% versus 0%, P = 0.004). For K. pneumoniae, carriage prevalence was higher in the azithromycin arm for BM (13.8% versus 8.7%, P = 0.055) but not for VS or NPS. Prevalence of azithromycin resistant K. pneumoniae was higher in the azithromycin arm for BM (3.6% versus 1.0%, P = 0.050) and VS (1.5% versus 0% P = 0.057). CONCLUSIONS: Oral intrapartum azithromycin did not reduce carriage of E. coli and K. pneumoniae and was associated with an increase in the prevalence of azithromycin-resistant E. coli and K. pneumoniae isolates in BM and VS.

Stillbirths, Neonatal Morbidity, and Mortality in Health-Facility Deliveries in Urban Gambia.

Background: The Gambia Demographic and Health Survey 2013 data showed that up to 63% of deliveries in the country occur in health facilities. Despite such a high rate, there are few facility-based studies on delivery outcomes in the country. This analysis ancillary to a randomized control trial describes occurrence of poor pregnancy outcomes in a cohort of women and their infants delivering in a government health facility in urban Gambia. Methods: Using clinical information obtained during the trial, we calculated rates of poor pregnancy outcomes including stillbirths, hospitalization and neonatal deaths. Logistic regression was used to calculate odds ratio (OR) and 95% confidence interval (CI) in the risk factors analysis. Results: Between April 2013 and 2014, 829 mothers delivered 843 babies, including 13 stillbirths [15.4 (7.1-23.8)] per 1,000 births. Among 830 live born infants, 7.6% (n = 63) required hospitalization during the 8-week follow-up period. Most of these hospitalizations (74.6%) occurred during the early neonatal period (<7 days of life). Severe clinical infections (i.e., sepsis, meningitis and pneumonia) (n = 27) were the most common diagnoses, followed by birth asphyxia (n = 13), major congenital malformations (n = 10), jaundice (n = 6) and low birth weight (n = 5). There were sixteen neonatal deaths, most of which also occurred during the early neonatal period. Overall, neonatal mortality rate (NMR) and perinatal mortality rate (PMR) were 19.3 (CI: 9.9-28.7) per 1,000 live births and 26.1 (CI: 15.3-36.9) per 1,000 total births, respectively. Severe clinical infections and birth asphyxia accounted for 37 and 31% of neonatal deaths, respectively. The risk of hospitalization was higher among neonates with severe congenital malformations, low birth weight, twin deliveries, and those born by cesarean section. Risk of mortality was higher among neonates with severe congenital malformations and twin deliveries. Conclusion: Neonatal hospitalization and deaths in our cohort were high. Although vertical interventions may reduce specific causes of morbidity and mortality, data indicate the need for a holistic approach to significantly improve the rates of poor pregnancy outcomes. Critically, a focus on decreasing the high rate of stillbirths is warranted. Clinical Trial Registration: ClinicalTrials.gov Identifier: NCT01800942.

Long-lasting effect of oral azithromycin taken by women during labour on infant nutrition: Follow-up cohort of a randomized clinical trial in western Gambia.

OBJECTIVE: To assess the effect of administering an oral dose of 2g of azithromycin in Gambian women during labour on infant growth. METHODS: Children whose mothers had been randomized to receive either an oral dose of 2g of azithromycin or placebo during labour were visited at home at the end of infancy by trained study nurses blind to the treatment allocation. The follow-up visit of these cohorts (exposed and non-exposed to azithromycin), which was not part of the original trial design, was conducted between November 2014 and May 2015 when the infants were 11 to 13 months of age. During visits, nurses recorded anthropometrical measurements and transcribed information from the infants' welfare cards. RESULTS: Four-hundred and sixty-five (79.6%) of the 584 infants aged 11-13 months at the time of the survey were recruited. The proportion of children with an age-adjusted Z-score <-2SD for mid-upper-arm circumference (MUAC) was lower among those exposed to azithromycin [1.3% versus 6.3%, OR = 0.21 95%CI (0.06,0.72), p = 0.006] and there was weak evidence of a difference in the proportion of infants with weight-for-age (WAZ) Z-score <-2SD [7.1% versus 12.1%, OR = 0.58 95%CI (0.33,1.04), p = 0.065]. For all other malnutrition indicators the proportions were similar in the exposed and un-exposed cohort. CONCLUSIONS: Our results show that azithromycin in labour may have a beneficial effect in MUAC among children who are below the curve. Larger studies with closer follow-up are warranted. TRIAL REGISTRATION (MAIN TRIAL): ClinicalTrials.gov Identifier NCT01800942.

Azithromycin in Labor Lowers Clinical Infections in Mothers and Newborns: A Double-Blind Trial.

BACKGROUND AND OBJECTIVES: We have recently completed a proof-of-concept trial showing that bacterial colonization decreased in women and newborns after the administration of azithromycin during labor. Here, we aim to assess the effect of the intervention on maternal and neonatal clinical infections. METHODS: This was a double-blind, placebo-controlled randomized trial. Gambian women in labor were given either an oral dose of azithromycin (2 g) or placebo. Follow-up was conducted for 8 weeks after delivery. RESULTS: From April 2013 to April 2014, we recruited 829 mothers and their 830 newborns. Sixteen infants died during the follow-up period (8 per arm). No maternal deaths or serious adverse events related to the intervention were reported. Maternal infections were lower in the azithromycin group (3.6% vs 9.2%; relative risk [RR], 0.40; 95% confidence interval [CI], 0.22-0.71; P = .002), as was the prevalence of mastitis (1.4% vs 5.1%; RR, 0.29; 95% CI, 0.12-0.70; P = .005) and fever (1.9% vs 5.8%; RR, 0.33; 95% CI, 0.15-0.74; P = .006). Among newborns, the overall prevalence of infections was also lower in the azithromycin group (18.1% vs 23.8%; RR, 0.76; 95% CI, 0.58-0.99; P = .052) and there was a marked difference in prevalence of skin infections (3.1% vs 6.4%; RR, 0.49; 95% CI, 0.25-0.93; P = .034). CONCLUSIONS: Azithromycin given to women in labor decreases infections in both women and newborns during the puerperal period. Larger studies designed to evaluate the effect of the intervention on severe morbidity and mortality are warranted.