Risk factors and etiology of neonatal sepsis after hospital delivery: A case-control study in a tertiary care hospital of Rajshahi, Bangladesh.

BACKGROUND: Sepsis is one of the major causes of neonatal death worldwide as well as in Bangladesh. The objective of the present study was to identify the risk factors and causative organisms of neonatal sepsis after delivery in a tertiary care hospital, Bangladesh.
METHODS: This was a case-control study conducted in the neonatal ward of Rajshahi Medical College Hospital (RMCH), a 1000-bed tertiary hospital situated in Rajshahi, Bangladesh. Neonates diagnosed as neonatal sepsis by clinical and laboratory parameters were included as cases in this study. Admitted neonates unsuspected or undiagnosed for sepsis were considered as controls. Maternal and neonatal information and their laboratory reports were collected and analyzed. Both bivariate and multiple logistic regression models were used to identify the risk factors of neonatal sepsis.
RESULTS: A total of 91 cases and 193 controls were included in the study. Maternal history of urinary tract infection (UTI) during the third trimester of pregnancy (aOR 2.75, 95% CI: 1.04-7.23, p <0.05), premature birth (aOR 2.77, 95% CI: 1.08-7.13, p <0.05) and APGAR score <7 at five minutes (aOR 2.58, 95% CI: 1.04-6.39, p <0.05) were associated with onset of neonatal sepsis in multiple logistic regression model. All these factors were also associated with developing early-onset neonatal sepsis, while maternal UTI and male sex of neonates were associated with developing late-onset neonatal sepsis. Escherichia coli (40.7%), Staphylococcus aureus (27.5%), and Klebsiella pneumoniae (18.7%) were the commonly isolated organisms causing neonatal sepsis. All these organisms were highly resistant to common antibiotics like amoxicillin, cephalosporins, aminoglycosides and quinolones. Carbapenemase group of drugs along with amikacin, nitrofurantoin and linezolid were the most sensitive drugs.
CONCLUSIONS: Strengthening the existing facility for antenatal screening for early diagnosis and treatment of maternal infection during pregnancy as well as identifying high-risk pregnancy for adequate perinatal management is necessary to prevent neonatal sepsis-related morbidity and mortality. Rational use of antibiotics according to local epidemiology and culture and sensitivity reports may minimize the increasing hazards of antibiotic resistance.

Introduction

Neonatal sepsis is a significant but neglected public health concern, especially in the lower and middle-income countries of sub-Saharan Africa and South-East Asia. Consequently, despite a decreasing trend in global neonatal mortality during the last two decades, the rate of reduction of sepsis-specific mortality has been much slower compared to that of other causes like premature birth or intrapartum complications in these regions [1]. More than six million neonates suffer from severe infections and sepsis annually in these regions [2]. It contributes to almost one-quarter of global neonatal deaths per year [3]. Bangladesh is a developing country in the South-East Asian region where sepsis contributes to almost 37% of all neonatal deaths [4].

Neonatal sepsis denotes a systemic inflammatory response syndrome in the presence of or as a result of suspected or proven infection in a neonate (within the first 28 days of life) [5, 6]. According to the age of onset, neonatal sepsis is divided into two classes: (i) early-onset neonatal sepsis (EONS) and (ii) late-onset neonatal sepsis (LONS). Usually, the onset of sepsis within the first 72 hours of life is referred to as EONS, while the onset of sepsis after 72 hours but within the first 28 days of life is referred to as LONS. It is anticipated that organisms acquired before and during delivery (or maternal-fetal infection) are mainly responsible for EONS, while organisms acquired after delivery from the environment (nosocomial or community sources) are responsible for LONS [7]. Case fatality of neonatal sepsis is high and many of the surviving neonates suffer from poor long-term neurodevelopmental outcomes as a consequence of CNS involvement, septic shock, or hypoxemia secondary to severe parenchymal lung disease [8]. Bacterial pathogens such as Klebsiella pneumoniae, Staphylococcus aureus, and coagulase-negative Staphylococcus are the most common causes of neonatal sepsis in developing countries [9]. These organisms are highly resistant to commonly used antibiotics, which makes them challenging to treat [10-12]. Moreover, early diagnosis and treatment of newborns with infection are unsatisfactory in resource-poor settings, which contributes to the high neonatal mortality due to sepsis [13].

There are epidemiological differences in the incidence, risk factors, pattern, and antimicrobial sensitivities of pathogens and mortality of neonatal sepsis among different regions and countries in the world [14]. Specific strategies suitable for specific countries to prevent and treat neonatal sepsis are needed to accelerate the progress of preventing neonatal morbidity and mortality. Identification of risk factors and early diagnosis and institution of therapy according to local epidemiology and antimicrobial resistance pattern can improve neonatal survival. There is a lack of evidence on risk factors and common causative agents with their sensitivity patterns of neonatal sepsis in Bangladesh. A case-control study conducted in Bangladesh focused on community-acquired LONS showed that underweight, admission in the winter season, primiparity, and home delivery were associated with LONS [15]. Another community-based study reporting neonatal infection within the first nine days of life demonstrated that history of child death in the family, large family, home delivery, unclean cord care, multiple birth, low birth weight, and perinatal asphyxia were associated with neonatal infection [16]. Some other studies reported that neonatal sepsis was associated with low birth weight, preterm neonates, meconium-stained liquor, and prolonged rupture of membrane [17, 18]. Gram-negative organisms predominated with Escherichia coli are the commonest causative agents, though this study is not robust enough to verify the risk factors of neonatal sepsis due to its cross-sectional nature [17]. However, these studies did not represent the scenario of the whole country as there were socio-economic and demographic disparities across the country. Moreover, most of the studies were community-based and authors considered births at both home and hospital.

The present study, therefore, aimed to determine the risk factors and etiology of neonatal sepsis among the neonates delivered in a tertiary care hospital in northern Bangladesh.

Methods

Study design and setting

This was a case-control study conducted in the neonatal ward of Rajshahi Medical College Hospital (RMCH) from January to December 2019. RMCH is a 1000-bed tertiary care hospital situated in Rajshahi city and it is the main referral medical institution in northern Bangladesh. This hospital has a 50-bed neonatal ward with a neonatal intensive care unit (NICU) facility.

Study population and sampling

The study population was all the neonates aged 0–28 days who were admitted to the neonatal ward of RMCH and born in this hospital either by vaginal delivery or cesarean section during the study period. A two population proportion formula (using open Epi version 2.3.1) was used to calculate the adequate sample size for the study by considering the proportion of mothers with a history of UTI during the third trimester (proved by a positive urine culture report or the presence of >5 pus cells/HPF in the microscopic test of urine with a history of clinical symptoms of UTI such as fever, burning sensation in micturition, etc., for those whose urine culture report was not available), among the controls of 13.5% (one of the main exposure variables), which was estimated from a previous study [19], 95% confidence interval, 80% power of the study control to case ratio of 2:1 to detect an estimated odds ratio of 2.5 and 10% non-response rate. Accordingly, 93 cases and 186 controls (a total sample size of 279) were enough. Cases and controls were selected using a proportional convenient sampling method according to inclusion and exclusion criteria. The distribution of cases and controls is shown in the Fig 1.

Fig 1

Distribution of cases and controls.

Inclusion and exclusion criteria

Neonates diagnosed for neonatal sepsis according to established clinical and hematological criteria of IMNCI (Integrated Management of Neonatal and Childhood Illness) and evidence of positive blood culture results were included as cases in this study. Neonates who were not suspected or diagnosed for neonatal sepsis and who were born in the obstetrics department and/or admitted to the neonatal ward of RMCH due to other indications such as low birth weight, neonatal jaundice, diarrhea, etc. during the study period were included as controls. Controls were matched for age with cases. Neonates who were born outside RMCH or clinically suspected as sepsis but not confirmed by hematological test and positive blood culture were excluded from the study.

Diagnosis of neonatal sepsis

Neonatal sepsis includes a range of systemic infections of the newborn, such as septicemia, meningitis, pneumonia, arthritis, osteomyelitis, etc. [6]. Among all these infections, septicemia, defined as generalized bacterial infection documented by a positive blood culture within the first 28 days of life, contributes to a large portion of neonatal morbidity and mortality due to sepsis [20]. We considered neonates with positive blood culture results as sepsis cases, as the facility of culture for other specimens was absent in the study center. According to the international pediatric sepsis consensus conference, neonatal sepsis was diagnosed by the presence of one or more of the established clinical features [either of fever (>37.5°C) or hypothermia (<35.5°C), fast breathing (>60 breaths per minute), severe chest indrawing, not feeding well, the movement only when stimulated, convulsion, lethargic or unconscious] and confirmed by the presence of two of the hematological criteria (total leukocyte count <4000 or >12000 cells/mm3, absolute neutrophil count <1500 cells/mm3 or >7500 cells/mm3, erythrocyte sedimentation rate (ESR) >15 in the first hour and platelet count <150 or >440 cells/m3) along with a positive blood culture test [5]. Early-onset neonatal sepsis (EONS) was defined as sepsis occurring within the first 72 hours of life, and that occurring after 72 hours and within 28 days of life was defined as late-onset neonatal sepsis (LONS) [19].

Blood culture and antimicrobial susceptibility testing

The blood sample was collected from clinically suspected patients by trained pediatric nurses and sent to the microbiology lab of RMCH for culture. 1 ml of blood was collected from each patient and directly inoculated into a pediatric FAN blood culture bottle. If a collection of 1 ml of blood was not possible or contraindicated by the consultant neonatologist, especially in low birth weight premature neonates due to their weight and total blood body volume, 0.5 ml of blood was collected. As blood of a lower volume than 0.5 ml significantly reduces the sensitivity [21], neonates from whom collection of 0.5 ml of blood was not clinically justified by the consultant neonatologist were excluded from the study. Collected samples were incubated in the BACT/Alert machine for up to 5 days. The BACT/Alert system is reported as highly sensitive with a positivity index of 0.94 for the gram-positive organism (S. epidermidis) and 0.95 for the gram-negative organism (E. coli) [21]. For identification of organisms, positive culture samples were directly inoculated onto MacConkey (MC) agar, chocolate agar, and blood agar (5% sheep blood) plates. MC plates were then incubated at 35°C in aerobic conditions. Chocolate and blood agar plates were incubated at 35°C in microaerophilic conditions (containing 5% CO2). Isolated organisms were identified using standard laboratory procedures. API 20E identification strips (bioMérieux, France) were used for further identification. Antimicrobial susceptibility test (AST) was carried out by Kirby–Bauer disc diffusion method [22] and susceptibility patterns were determined following CLSI guidelines [23]. Antimicrobial susceptibility was tested for a panel of antibiotics (Oxoid, UK). E. coli ATCC 25922 and Pseudomonas aeruginosa ATCC 27853 were used as quality control strains. Non-susceptibility to at least one agent in three or more antimicrobial categories was defined as multidrug resistance (MDR) [24].

Data collection procedure

Data related to maternal and neonatal risk factors as well as laboratory parameters and blood culture reports were extracted from medical records of the mother during delivery and admitted neonates using a structured checklist. In the case of any missing information about maternal and neonatal risk factors, the mother of the neonate was interviewed by two trained nurses. Detailed socio-demographic information was not collected due to our limited resources.

Outcome variable

In this study, neonatal sepsis was the primary outcome variable. This was further classified into two classes: (i) early-onset neonatal sepsis (EONS) defined as the onset of sepsis within the first 72 hours of life, and (ii) late-onset neonatal sepsis, defined as the onset of sepsis after the first 72 hours but within 28 days of life.

Independent variables

Independent variables were: maternal variables such as maternal age, maternal UTI during the third trimester of pregnancy, prolonged labor, premature rupture of membrane, and mode of delivery; and neonatal variables such as the age of neonate, sex of neonate, prematurity (gestational age), weight at birth, and APGAR score at 5 minutes. These potential risk factors were selected from the evidence of previous studies [19, 25, 26].

Ethics approval and consent to participate

Ethical approval for this study was obtained from the Ethical Review Committee of Rajshahi Medical College [Ref. RMC/ERC/2017-2019/199/179]. Informed written consent was obtained from the mother of the neonate before enrollment in the study.

Statistical analysis

All statistical analyses were carried out using SPSS (IBM version 24.0). Statistical analysis was done: (i) to determine the risk factors of neonatal sepsis including all cases and controls and (ii) to determine the risk factors of early and late-onset neonatal sepsis including the cases aged 0 to 72 hours and 72 hours to 28 days and their age-matched controls respectively. The chi-square test was carried out to determine differences among groups concerning the outcome variables. Both bivariate and multiple logistic regression models were used to generate crude odds ratios (cOR) and adjusted odds ratios (aOR) with 95% confidence intervals (CI) for significance testing. Variables that achieved p-value <0.05 in bivariate analysis were entered into the multiple logistic regression models.

Results

Characteristics of the participants

A total number of 284 participants were included in the study, 91 diagnosed as neonatal sepsis (cases), and 193 diagnosed as no sepsis (controls). Among cases, 56 (61.5%) and 35 (38.5%) were diagnosed as EONS and LONS respectively. Almost half of the neonates of both cases and controls were female. 65.5% of the mothers of neonates were of 18–35 years; 14% of them had a history of UTI during the third trimester of pregnancy (24% among cases, 9% among controls). 16% of mothers had prolonged labor (24% among cases and 13% among controls), and 19.4% of them had premature rupture of membrane (27.5% among cases and 15.5% among controls). A total of 38.7% of neonates were delivered by cesarean section (49.5% among cases and 33.7% among controls). Prematurity, low birth weight, and APGAR score <7 at 5 minutes were more prevalent among cases (46% vs 18.7%, 54% vs 25.4%, and 31% vs 11.4% respectively among cases and controls). The chi-square test demonstrated that maternal UTI during 3rd trimester, prolonged labor, premature rupture of membrane, mode of delivery, prematurity, weight at birth, and APGAR score at 5 minutes were significantly associated with neonatal sepsis (Table 1).

Table 1

Maternal and neonatal characteristics of cases and control.

Variables	Category	Total, N (%)	Case, N (%)	Control, N (%)	p-value
Maternal age (year)	<18	60 (21.1)	21 (23.1)	39 (20.2)	0.783
	18 to 35	186 (65.5)	57 (62.6)	129 (66.8)
	>35	38 (13.4)	13 (14.3)	25 (13.0)
Maternal UTI during 3rd trimester	Yes	40 (14.1)	22 (24.2)	18 (9.3)	0.001
	No	244 (85.9)	69 (75.8)	175 (90.7)
Prolonged labor	Yes	47 (16.5)	22 (24.2)	25 (13.0)	0.018
	No	237 (83.5)	69 (75.8)	168 (87.0)
Premature rupture of membrane	Yes	55 (19.4)	25 (27.5)	30 (15.5)	0.018
	No	229 (80.6)	66 (72.5)	163 (84.5)
Mode of delivery	Caesarean	110 (38.7)	45 (49.5)	65 (33.7)	0.011
	Vaginal	174 (61.3)	46 (50.5)	128 (66.3)
Age of neonate (day)	0 to 3	172 (60.6)	56 (61.5)	116 (60.1)	0.817
	3or 4–28	112 (39.4)	35 (38.5)	77 (39.9)
Sex of neonate	Female	151 (53.2)	48 (52.7)	103 (53.4)	0.922
	Male	133 (46.8)	43 (47.3)	90 (46.6)
Prematurity	Yes (<37 weeks)	78 (27.5)	42 (46.2)	36 (18.7)	0.001
	No (≥37 weeks	206 (72.5)	49 (53.8)	157 (81.3)
Weight at birth (gram)	Low, <2500	98 (34.5)	49 (53.8)	49 (25.4)	0.001
	Normal, ≥2500	186 (65.5)	42 (46.2)	144 (74.6)
APGAR score at 5 minutes	<7	50 (17.6)	28 (30.8)	22 (11.4)	0.001
	≥7	234 (82.4)	63 (69.2)	171 (88.6)

Risk factors of neonatal sepsis

Multiple binary logistic regression model demonstrated that mothers having UTI during the 3rd trimester had a 2.75-fold greater risk of neonatal sepsis than their counterparts (aOR = 2.75; 95% CI: 1.04–7.23; p<0.05). Premature neonates were at 2.77 times higher risk for getting sepsis than neonates delivered in time (aOR = 2.77, 95% CI: 1.08–7.13; p<0.05). Neonates having a lower APGAR score (<7) at 5 minutes were more likely to get sepsis than neonates with APGAR score of 7 and above (aOR = 2.57, 95% CI: 1.02–6.43; p<0.05). However, bivariate logistic model showed that prolonged labor (cOR = 2.14, 95% CI: 1.13–4.06; p<0.05), premature rupture of membrane (cOR =: 2.06, 95% CI: 1.13–3.76; p<0.05), mode of delivery (cOR = 1.93, 95% CI: 1.16–3.20; p<0.05), and weight at birth (cOR = 3.43, 95% CI: 2.03–3.26; p<0.05) were the most influential factors of neonatal sepsis (Table 2).

Table 2

Bivariate and multiple logistic regressions for risk factors of neonatal sepsis.

Variables	Category	Case, N (%)	Control, N (%)	cOR (95% CI)	aOR (95% CI)
Maternal age (year)	<18	21 (23.1)	39 (20.2)	1.04 (0.44–2.43)
	18 to 35	57 (62.6)	129 (66.8)	0.85 (0.41–1.78)
	>35	13 (14.3)	25 (13.0)
Maternal UTI during 3rd trimester	Yes	22 (24.2)	18 (9.3)	3.10 (1.57–6.13)*	2.75 (1.04–7.23)*
	No	69 (75.8)	175 (90.7)
Prolong labor	Yes	22 (24.2)	25 (13.0)	2.14 (1.13–4.06)*	1.89 (0.70–5.08)
	No	69 (75.8)	168 (87.0)
Premature rupture of membrane	Yes	25 (27.5)	30 (15.5)	2.06 (1.13–3.76)*	1.44 (0.60–3.45)
	No	66 (72.5)	163 (84.5)
Mode of delivery	Caesarean	45 (49.5)	65 (33.7)	1.93 (1.16–3.20)*	1.47 (0.67–3.22)
	Vaginal	46 (50.5)	128 (66.3)
Age of neonate (day)	0 to 3	56 (61.5)	116 (60.1)	1.06 (0.64–1.77)
	3–28 days	35 (38.5)	77 (39.9)
Sex of neonate	Female	48 (52.7)	103 (53.4)	0.98 (0.59–1.61)
	Male	43 (47.3)	90 (46.6)
Prematurity	Yes (<37 weeks)	42 (46.2)	36 (18.7)	3.74 (2.16–6.47)*	2.77 (1.08–7.13)*
	No (≥37 weeks)	49 (53.8)	157 (81.3)
Weight at birth (gram)	Low, <2500	49 (53.8)	49 (25.4)	3.43 (2.03–5.79)*	1.27 (0.50–3.26)
	Normal, ≥2500	42 (46.2)	144 (74.6)
APGAR score at 5 minutes	<7	28 (30.8)	22 (11.4)	3.46 (1.84–6.48)*	2.57 (1.02–6.43)*
	≥7	63 (69.2)	171 (88.6)

N.B.

*p-value <0.05, CI: Confidence interval, cOR: crude odds ratio, aOR: Adjusted odds ratio.

Risk factors for early and late-onset neonatal sepsis

Tables 3 and 4 show the risk factors of early and late-onset neonatal sepsis respectively. Multiple logistic regression models showed that maternal UTI during the third trimester of pregnancy was a significant predictor of both early (aOR = 2.78, 95% CI: 1.07–7.28; p<0.05) and late-onset (aOR = 5.48, 95% CI: 1.58–18.99; p<0.05) neonatal sepsis. Among neonatal factors, premature birth (aOR = 2.84, 95% CI:1.13–7.12; p<0.05) and APGAR score <7 at 5 minutes (aOR = 2.58, 95% CI: 1.04–6.39; p<0.05) were associated with increased risk of EONS (Table 3) while only male sex of neonate diminished the risk of LONS by 67% (aOR = 0.33, 95% CI: 0.13–0.88; p<0.05) compared to female neonate (Table 4).

Table 3

Bivariate and multiple logistic regression for risk factors of early-onset neonatal sepsis.

Variables	Category	Case, N (%)	Control, N (%)	cOR (95% CI)	aOR (95% CI)
Maternal age (year)	<18	13 (23.2)	22 (19.0)	0.99 (0.29–3.34)
	18 to 35	37 (66.1)	84 (72.4)	0.73 (0.25–2.17)
	>35	6 (10.7)	10 (8.6)
Maternal UTI during 3rd trimester	Yes	13 (23.2)	11 (9.5)	2.89 (1.20–6.94)*	2.78 (1.07–7.28)*
	No	43 (76.8)	105 (90.5)
Prolong labor	Yes	11 (19.6)	13 (11.2)	1.94 (0.81–4.65)
	No	45 (80.4)	103 (88.8)
Premature rupture of membrane	Yes	15 (26.8)	19 (16.4)	1.87 (0.87–4.03)
	No	41 (73.2)	97 (83.6)
Mode of delivery	Caesarean	29 (51.8)	39 (33.6)	2.12 (1.11–4.06)*	1.50 (0.69–3.25)
	Vaginal	27 (48.2)	77 (66.4)
Sex of neonate	Female	29 (51.8)	46 (39.7)	1.63 (0.86–3.11)
	Male	27 (48.2)	70 (60.3)
Prematurity	Yes (<37 weeks)	27 (48.2)	24 (20.7)	3.57 (1.79–7.12)*	2.84 (1.13–7.12)*
	No (≥37 weeks)	29 (51.8)	92 (79.3)
Weight at birth (gram)	Low, <2500	31 (55.4)	33 (28.4)	3.12 (1.61–6.06)*	1.25 (0.50–3.16)
	Normal, ≥2500	25 (44.6)	83 (71.6)
APGAR score at 5 minutes	<7	14 (25.0)	13 (11.2)	2.64 (1.15–6.09)*	2.58 (1.04–6.39)*
	≥7	42 (75.0)	103 (88.8)

N.B.

*p-value <0.05, CI: Confidence interval, cOR: crude odds ratio, aOR: Adjusted odds ratio.

Table 4

Bivariate and multiple logistic regression for risk factors of late-onset neonatal sepsis.

Variables	Category	Case, N (%)	Control, N (%)	cOR (95% CI)	aOR (95% CI)
Maternal age (year)	<18	8 (22.9)	17 (22.1)	1.01 (0.29–3.45)
	18 to 35	20 (57.1)	45 (58.4)	0.95 (0.34–2.69)
	>35	7 (20.0)	15 (19.5)
Maternal UTI during 3rd trimester	Yes	9 (25.7)	7 (9.1)	3.46 (1.17–10.25)*	5.48 (1.58–18.99)*
	No	26 (74.3)	70 (90.9)
Prolong labor	Yes	11 (31.4)	12 (15.6)	2.48 (0.97–6.37)
	No	24 (68.6)	65 (84.4)
Premature rupture of membrane	Yes	10 (28.6)	11 (14.3)	2.40 (0.91–6.35)
	No	25 (71.4)	66 (85.7)
Mode of delivery	Caesarean	16 (45.7)	26 (33.8)	1.65 (0.73–3.74)
	Vaginal	19 (54.3)	51 (66.2)
Sex of neonate	Female	19 (54.3)	57 (74.0)	0.42 (0.18–0.96)*	0.33 (0.13–0.88)*
	Male	16 (45.7)	20 (26.0)
Prematurity	Yes (<37 weeks)	15 (42.9)	12 (15.6)	4.06 (1.64–10.09)*	2.34 (0.71–7.70)
	No (≥37 weeks)	20 (57.1)	65 (84.4)
Weight at birth (gram)	Low, <2500	18 (51.4)	16 (20.8)	4.04 (1.71–9.56)*	2.19 (0.64–7.53)
	Normal, ≥2500	17 (48.6)	61 (79.2)
APGAR score at 5 minutes	<7	14 (40.0)	9 (11.7)	5.04 (1.91–13.29)*	2.10 (0.61–7.26)
	≥7	21 (60.0)	68 (88.3)

N.B.

*p-value <0.05, CI: Confidence interval, cOR: crude odds ratio, aOR: Adjusted odds ratio.

Causative organisms of neonatal sepsis

Escherichia coli was the most frequently isolated gram-negative organism from blood samples of suspected neonates of sepsis (40.7%) followed by Klebsiella pneumoniae (18.7%). These two organisms were the most common cause of both early and late-onset neonatal sepsis, though Klebsiella pneumoniae was more likely associated with LONS (10.7% of EONS vs 31.4% of LONS). Among gram-positive organisms, Staphylococcus aureus (27.5%) and Staphylococcus saprophyticus (8.8%) were most commonly isolated from blood samples (Table 5).

Table 5

Causative organisms of neonatal sepsis.

Organism	Total, N (%)	Mode of onset		Gestational age		Birth weight
		EONS, N (%)	LONS, N (%)	<37 weeks, N (%)	≥37 weeks, N (%)	<2500 g, N (%)	≥2500 g, N (%)
Escherichia coli	37 (40.7)	26 (46.4)	11 (31.4)	17 (40.5)	20 (40.8)	22 (44.9)	15 (35.7)
Klebsiella pneumoniae	17 (18.7)	6 (10.7)	11 (31.4)	8 (19.0)	9 (18.4)	10 (20.4)	7 (16.7)
Staphylococcus aureus	25 (27.5)	17 (30.4)	8 (22.9)	11 (26.2)	14 (28.6)	11 (22.4)	14 (33.3)
Staphylococcus saprophyticus	8 (8.8)	5 (8.9)	3 (8.6)	5 (11.9)	3 (6.1)	4 (8.2)	4 (9.5)
Staphylococcus epidermidis	3 (3.3)	1 (1.8)	2 (5.7)	1 (2.4)	2 (4.1)	2 (4.1)	1 (2.4)
Streptococcus viridans	1 (1.1)	1 (1.8)	0 (0.0)	0 (0.0)	1 (2.0)	0 (0.0)	1 (2.4)

Antibiotic resistance pattern

Table 6 shows the pattern of antibiotic resistance of causative organisms of neonatal sepsis. Among the beta-lactam antibiotics used for gram-negative organisms, both Escherichia coli and Klebsiella pneumoniae showed the highest resistance to amoxicillin and clavulanic acid combination (57% and 70.6% respectively). Though Klebsiella pneumoniae was highly sensitive to imipenem and meropenem, Escherichia coli was moderately resistant to these drugs (32% and 46% respectively). These organisms were highly resistant to almost all non-β-lactum antibiotics tested, such as the third-generation cephalosporins, aminoglycosides, and quinolones. However, levofloxacin was quite sensitive against these organisms (resistance rate 40% and 35% for E. coli and K. pneumoniae respectively).

Table 6

Antibiotic resistance pattern (percentage of resistance) of causative organisms of neonatal sepsis.

Antibiotic	Organism
	Escherichia coli	Klebsiella pneumoniae	Staphylococcus aureus	Staphylococcus saprophyticus	Staphylococcus epidrmidis
	(n = 37), R%	(n = 17), R%	(n = 25), R%	(n = 8), R%	(n = 3), R%
MDR	100	100	100	100	100
β-lactum antibiotics
Amoxicillin			92.0	37.5	100
Amoxicillin + clavulanic acid	56.8	70.6	44.0	50.0	33.3
Cloxacillin			52.0	25.0	33.3
Imipenem	32.4	0.0	24.0	12.5	33.3
Meropenem	45.9	0.0	40.0	25.0	33.3
Non-β-lactum antibiotics
Ceftriaxone	75.7	76.5		62.5	66.7
Ceftazidime	62.2	58.8	64.0	100	100
Cefuroxime	89.2	64.7	60.0	62.5	0.0
Cefepime	73.0	47.1	48.0	25.0	33.3
Azithromycin			80.0	100	100
Gentamicin	75.7	64.7	48.0	75.0	33.3
Amikacin	70.3	64.7	32.0	75.0	66.7
Ciprofloxacin	78.4	52.9	56.0	75.0	33.3
Levofloxacin	40.5	35.3	56.0	50.0	0.0
Cotrimoxazole	73.0	76.5	72.0	75.0	66.7
Doxycycline	78.4	52.9	44.0	75.0	33.3
Nitrofurantoin	56.8	52.9	20.0	50.0	0.0
Linezolid			4.0	12.5	33.3

R = Resistance

Gram-positive organisms were moderately sensitive to almost all β-lactum antibiotics except amoxicillin. Resistance rates of these organisms to Non-β-lactum antibiotics like the third-generation cephalosporins, aminoglycosides, and quinolones, and others were comparatively higher than β-lactum antibiotics. However, amikacin, nitrofurantoin, and linezolid were still sensitive against the gram-positive organisms, especially Staphylococcus aureus (Table 6).

Discussion

The present study aimed to evaluate the maternal and neonatal risk factors of developing sepsis, both early and late-onset, among the neonates delivered in a tertiary care hospital in northern Bangladesh. Among the diagnosed neonatal sepsis cases, 61.5% were diagnosed as EONS and 38.5% were diagnosed as LONS. The prevalence of EONS was much lower found in a study conducted in Dhaka, Bangladesh (35%) [27]; the sample size of that study was not large enough to conclude. Our finding is consistent with previous studies conducted in different countries of similar economic conditions like India (67%) [12], Nepal (78%) [10], Ethiopia (77%) [19], and Ghana (82%) [25].

Our study showed that neonates with a history of maternal UTI during the third trimester of pregnancy were five times more prone to developing sepsis. This was also found in the case of both EONS and LONS when the regression model was carried out separately. A similar result was found in a meta-analysis including studies from all over the world; it reported that lab-confirmed maternal infection or bacterial colonization significantly increases the risk of neonatal sepsis during the first week of life, which includes both EONS and LONS according to our definition [28]. Maternal infections may frequently transmit to the baby in utero or during passage through the birth canal which usually causes neonatal sepsis. Other maternal risk factors, prolonged labor and premature rupture of membrane, which increase the risk of the chance of ascending infection from the birth canal into the amniotic fluid were found to increase the risk of development of neonatal sepsis in different studies [19, 28, 29], though these factors were not associated with increased risk of sepsis in our study. Perhaps proper management of prolonged labor and premature rupture of the membrane in our tertiary care setting had minimized the risk of ascending infection.

Among neonatal factors, premature birth and APGAR scores of <7 at 5 minutes were found to be associated with overall neonatal sepsis as well as developing EONS. We could not find any association between low birth weight and neonatal sepsis. Preterm birth and low birth weight were reported as risk factors of neonatal sepsis in several previous studies [17, 18, 30, 31]. However, some evidence found no association between neonatal sepsis and preterm birth or low birth weight [19, 26]. A lower APGAR score, which leads to perinatal asphyxia resulting in immunological insult, was also reported as an important risk factor of neonatal sepsis in different studies [16, 19, 26].

In our study, gram-negative organisms were more commonly isolated than gram-positive organisms. Escherichia coli was the predominant gram-negative bacteria followed by Klebsiella pneumoniae whereas Staphylococcus aureus was the predominant gram-positive organism. These organisms were also most commonly isolated from the neonatal blood samples of a previous study in Bangladesh [17]. Another study from Bangladesh reported Klebsiella pneumoniae as the most commonly isolated organism [27]. However, this study included blood samples mostly from LONS patients, and Klebsiella pneumoniae mainly caused LONS also in our study samples. Klebsiella pneumonia, Escherichia coli, Staphylococcus aureus, and coagulase-negative Staphylococcus were reported as the most common causative organisms of neonatal sepsis worldwide [9, 10, 12, 32]. Escherichia coli and Klebsiella pneumoniae are normal members of gastrointestinal flora and cause a range of infections including UTI, pneumonia, and septicemia. Maternal colonization by these organisms increases the neonatal risk of being infected by them [28].

Antimicrobial resistance is a major challenge for clinical management of neonatal sepsis. In our study, all the isolated bacteria were multidrug-resistant. Both gram-negative and gram-positive organisms were highly resistant to commonly available antibiotics like amoxicillin, cephalosporins, aminoglycosides, and quinolones. A similar pattern of a very high prevalence of multidrug-resistant organisms was also reported in previous studies from Bangladesh [17, 27] and also from different countries of the world like India, Nepal, and Ethiopia [10-12]. Our study revealed that the carbapenemase group of drugs (imipenem and meropenem) was mostly sensitive against both gram-positive and gram-negative bacteria. Some other antibiotics like amikacin, nitrofurantoin, and linezolid were also sensitive, especially against gram-positive organisms (Staphylococcus aureus). A similar pattern of sensitivity was also reported in previous studies conducted in Bangladesh [27] and the neighboring countries like India and Nepal [10, 12].

Despite being a tertiary care hospital, the study institution lacks specific protocol regarding the use of the first, second, and third-line antibiotics used to treat neonatal sepsis. Broad-spectrum antibiotics, mainly ceftriaxone and amikacin are being used most commonly as empirical antibiotics in case of suspected sepsis at the time of admission, as these two antibiotics are available in the hospital through government supply. However, ceftriaxone showed a high level of resistance, though amikacin remained moderately sensitive, mostly against gram-positive bacteria. Based on our findings, levofloxacin and imipenem combination may be the drug of choice for empirical use in neonatal sepsis.

Strength and limitation of the study

The present study was the very first attempt to identify the risk factors and causative organisms of sepsis among hospital-borne neonates in the northern region of Bangladesh, to the best of our knowledge. Despite the fact, we would like to admit some limitations of the study. Firstly, this was a single-center study with a small sample size and both cases and controls were included from neonates admitted in the same tertiary care hospital. The findings may not be inferential for the neonates borne in the home or primary care settings. Secondly, we could not include detailed socio-demographic information due to our limited resources, which may have a role in developing neonatal sepsis. Thirdly, all the mothers classified as having UTI in the third trimester did not have proof of positive urine culture and in those cases, having >5 pus cells per HPF was considered as evidence of UTI. So there is a probability of classifying the mothers having sterile pyuria as UTI that can potentially confound the result. Finally, specific characterization of MDR bacteria (such as MRSA, ESBL, etc.) and molecular-based specifications have not been done due to a lack of well-established laboratory facilities, and detection of some UTIs might be missed to make an underestimated result. Therefore, the results of this study are recommended to be interpreted with caution. Further study with a larger sample of cases from multiple centers and healthy controls from the community is suggested to verify the risk factors found in our study. Other socio-demographic factors that we could not include due to our limited resources should also be considered. Moreover, the molecular characterization of MDR bacteria is suggested for a better understanding of the epidemiology and resistance mechanism of the causative organisms of neonatal sepsis.

Conclusions

Our result has demonstrated that the risk of developing neonatal sepsis was higher during the first 72 hours of a neonate’s life. Maternal history of UTI during the third trimester of pregnancy along with some neonatal factors such as premature birth and APGAR score of <7 at 5 minutes after birth was the significant risk factor of neonatal sepsis. Proper and adequate antenatal screening for early diagnosis and treatment of maternal infection during pregnancy as well as identifying high-risk pregnancy for adequate perinatal management of neonates are recommended to prevent neonatal sepsis-related morbidity and mortality. It was also observed that a high prevalence of multidrug-resistant organisms had made clinical management challenging. According to our findings, linezolid, nitrofurantoin, and carbapenems (meropenem and meropenem) may be the potential drugs of choice for empirical therapy to treat neonatal sepsis. However, the antibiotics should preferably be used according to the culture and sensitivity report at the earliest opportunity to reduce the risk of developing resistance against these drugs.

(SAV)

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4 Sep 2020

PONE-D-20-13278

Risk factors and etiology of neonatal sepsis after hospital delivery: a case-control study in a tertiary care hospital of Rajshahi, Bangladesh

PLOS ONE

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Comments to the Author

1. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Yes

Reviewer #2: Yes

**********

2. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #2: Yes

**********

3. Have the authors made all data underlying the findings in their manuscript fully available?

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Reviewer #1: Yes

Reviewer #2: Yes

**********

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Reviewer #2: Yes

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Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: The study evaluates risk factors and etiology of neonatal sepsis, is well designed, but there is a major point needing to be clarified

MAJOR COMMENTS

Diagnosis of neonatal sepsis was based on positive blood culture, in this sense is important to describe the sensitivity and specificity of the of the diagnosis assay.

Although Blood culture assays is considered a gold standard, it has showed limited sensitivity for neonatal sepsis diagnosis, especially in low birth weight premature neonates in who its difficult to draw 1 ml blood due to their weight and total blood body volume; how does this explain?

Table 5 show a descriptive analysis, it would be desirable to include bivariate and multiregression analysis if applicable for causal bacteria and EONS or LONS sepsis

In the multidrug-resistant analysis authors report high prevalence of MDR multidrug-organisms; however, the MDR was no characterized on molecular based assay as the authors describe in the limitations statement. Therefore, its recommends to take the results with caution. Please explain the concern and resolve.

MINOR COMMENTS

Mistakes in the bibliographic references

There are some mistakes in the bibliography; in the introduction in page 5 line 94 reference appear as “?”. Please check and resolve.

Is desirable to refer the international consensus for definition of sepsis: Goldstein B, Giroir B, Randolph A. International pediatric sepsis consensus conference: Definitions for sepsis and organ dysfunction in pediatrics. Pediatr Crit Care Med 2005; 6: 2-8.

Reviewer #2: 1)Profreading preferably by a native speaker

2)Introduction:INTRODUCTION :line 95-96:the cited study is not clear,there is no relation with the sentence just before and after it.

METHODS: Line 114 Expectant mothers are diagnosed to have UTI based on wcc count in the urine .As cultures are the gold standard to diagnose UTI ,would you regard everyone with sterile pyuria to have UTI?

121:IMCI should be replace with IMNCI

124:What was the indication of admission for control neonates

Discussion:Please mention the protocol regarding the use of first ,second and third line antibiotics used to treat neonatal sepsis in your centre,if any.If no any such protocol what is the current most common empricial antibiotic used in a case of suspected sepsis at the time of admission?

**********

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Reviewer #1: No

Reviewer #2: Yes: Dr Bhishma Pokhrel

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Submitted filename: Comments to manuscript PONE-D-20-13278.pdf

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1 Oct 2020

Journal Name: PLOS ONE

Tracking No. (Manuscript ID): PONE-D-20-13278

Manuscript Title: " Risk factors and etiology of neonatal sepsis after hospital delivery: a case-control study in a tertiary care hospital of Rajshahi, Bangladesh"

Dear Editor

Thank you very much for providing reviewer’s comments on our manuscript. We have modified and revised the manuscript accordingly, and detailed point–by-point corrections are given below:

Response to reviewer comments:

Reviewer #1: The study evaluates risk factors and etiology of neonatal sepsis, is well designed, but there is a major point needing to be clarified.

Response to Reviewer Comments: Thank you very much for your comments on our manuscript.

MAJOR COMMENTS

Diagnosis of neonatal sepsis was based on positive blood culture, in this sense is important to describe the sensitivity and specificity of the of the diagnosis assay.

Response to Reviewer Comments: We have described this issue with reference in Page 8 Line 158-159. [Manuscript with Track Changes].

Although Blood culture assays is considered a gold standard, it has showed limited sensitivity for neonatal sepsis diagnosis, especially in low birth weight premature neonates in who its difficult to draw 1 ml blood due to their weight and total blood body volume; how does this explain?

Response to Reviewer Comments: We have described and explained the issue in Page 8, Line 152-157. [Manuscript with Track Changes].

Table 5 show a descriptive analysis, it would be desirable to include bivariate and multi regression analysis if applicable for causal bacteria and EONS or LONS sepsis

Response to Reviewer Comments: Thank you very much for your comments, Table 5 shows the frequency of each category of mode of onset, gestational age and birth weight for different organisms such as Escherichia coli, Klebsiella pneumoniae, etc. So, we think there are no scope to apply bivariate and multiple regression analysis in here.

In the multidrug-resistant analysis authors report high prevalence of MDR multidrug-organisms; however, the MDR was no characterized on molecular based assay as the authors describe in the limitations statement. Therefore, its recommends to take the results with caution. Please explain the concern and resolve.

Response to Reviewer Comments: The concern was briefly discussed in Page 21, Line 342-344. [Manuscript with Track Changes]

MINOR COMMENTS

Mistakes in the bibliographic references

There are some mistakes in the bibliography; in the introduction in page 5 line 94 reference appear as “?”. Please check and resolve.

Response to Reviewer Comments: We have checked and made correction [Page 5 Line 94]. [Manuscript with Track Changes]

Is desirable to refer the international consensus for definition of sepsis: Goldstein B, Giroir B, Randolph A. International pediatric sepsis consensus conference: Definitions for sepsis and organ dysfunction in pediatrics. Pediatr Crit Care Med 2005; 6: 2-8.

Response to Reviewer Comments: According to your suggestions, we have revised this issue in Page 7-8 Line 138-146. [Manuscript with Track Changes]

Reviewer #2:

1) Prof-reading preferably by a native speaker

Response to Reviewer Comments: Thank you for your comments on our manuscript. We have tried with our best to make correction in English throughout the manuscript.

2) Introduction: INTRODUCTION : line 95-96:the cited study is not clear, there is no relation with the sentence just before and after it.

Response to Reviewer Comments: We have made correction [Page 5 Line 94]. [Manuscript with Track Changes]

METHODS: Line 114 Expectant mothers are diagnosed to have UTI based on wcc count in the urine .As cultures are the gold standard to diagnose UTI ,would you regard everyone with sterile pyuria to have UTI?

Response to Reviewer Comments: We described this issue in Page 6 Line 115-118 and in Page 21, Line 337-340. [Manuscript with Track Changes]

121: IMCI should be replace with IMNCI

Response to Reviewer Comments: We have made correction [Page 7 Line 125]. [Manuscript with Track Changes]

124:What was the indication of admission for control neonates

Response to Reviewer Comments: The indication of admission for control neonates has been mentioned in Page 7 Line 128-129. [Manuscript with Track Changes]

Discussion: Please mention the protocol regarding the use of first, second and third line antibiotics used to treat neonatal sepsis in your centre, if any. If no any such protocol what is the current most common empricial antibiotic used in a case of suspected sepsis at the time of admission?

Response to Reviewer Comments: We have discussed about this issue in Page 20 Line 324-328. [Manuscript with Track Changes]

We would like to thank the reviewers for the valuable comments. We have revised the documents to the best of our ability, but we will definitely be happy to provide further improvement if there are further clarifications required.

With best regards

Dr. Md. Golam Hossain

Professor of Health Research Group

Department of Statistics, University of Rajshahi

Rajshahi-6205, Bangladesh

E-mail: hossain95@yahoo.com

Submitted filename: Response to Reviewers.docx

Click here for additional data file.

22 Oct 2020

PONE-D-20-13278R1

Risk factors and etiology of neonatal sepsis after hospital delivery: a case-control study in a tertiary care hospital of Rajshahi, Bangladesh

PLOS ONE

Dear Dr. Hossain,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

Your revised manuscript has been re-reviewed by the original reviewers. The reviewer still has questions. Also, I would like to suggest that you ask an Native English speaker to go through your manuscript and makes the necessary edition before your re-submission.

Please submit your revised manuscript by two weeks. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file.

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A rebuttal letter that responds to each point raised by the academic editor and reviewer(s). You should upload this letter as a separate file labeled 'Response to Reviewers'.

A marked-up copy of your manuscript that highlights changes made to the original version. You should upload this as a separate file labeled 'Revised Manuscript with Track Changes'.

An unmarked version of your revised paper without tracked changes. You should upload this as a separate file labeled 'Manuscript'.

If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter. Guidelines for resubmitting your figure files are available below the reviewer comments at the end of this letter.

If applicable, we recommend that you deposit your laboratory protocols in protocols.io to enhance the reproducibility of your results. Protocols.io assigns your protocol its own identifier (DOI) so that it can be cited independently in the future. For instructions see: http://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols

We look forward to receiving your revised manuscript.

Kind regards,

Yung-Fu Chang

Academic Editor

PLOS ONE

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Reviewers' comments:

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Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.

Reviewer #1: All comments have been addressed

Reviewer #2: All comments have been addressed

**********

2. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Yes

Reviewer #2: Yes

**********

3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #2: Yes

**********

4. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

Reviewer #2: Yes

**********

5. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

Reviewer #2: Yes

**********

6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: The authors attended all of the recommendations; corrections were made in the background, methodology, results and bibliography sections.

The manuscript is OK.

Reviewer #2: There are still some errors in english language at some places so please try to be as accurate as possible .

What combination of two antibiotics would you recommend to start as an empirical therapy in a case of suspected sepsis as concluded from this study as opposed to the existing ceftriaxone and amikacin ?

**********

7. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files.

If you choose “no”, your identity will remain anonymous but your review may still be made public.

Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy.

Reviewer #1: Yes: Yelda A. Leal

Reviewer #2: Yes: Bhishma Pokhrel

[NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.]

While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org. Please note that Supporting Information files do not need this step.

27 Oct 2020

Journal Name: PLOS ONE

Manuscript ID: PONE-D-20-13278R1

Manuscript Title: “Risk factors and etiology of neonatal sepsis after hospital delivery: a case-control study in a tertiary care hospital of Rajshahi, Bangladesh”

Dear Editor

Thank you very much for providing reviewer’s comments on our manuscript. We have modified and revised the manuscript accordingly, and detailed point–by-point corrections are given below:

Response to reviewer comments:

Reviewer #2:

There are still some errors in English language at some places so please try to be as accurate as possible.

Response to Reviewer Comments: Thank you very much for your comments on our manuscript. We have revised and tried our best to improve English language of the manuscript.

What combination of two antibiotics would you recommend to start as an empirical therapy in a case of suspected sepsis as concluded from this study as opposed to the existing ceftriaxone and amikacin?

Response to Reviewer Comments: We have discussed about this issue in Page, 20; Line: 328-329.

We would like to thank the reviewers for the valuable comments. We have revised the documents to the best of our ability, but we will definitely be happy to provide further improvement if there are further clarifications required.

With best regards

Dr. Md. Golam Hossain

Professor of Health Research Group

Department of Statistics, University of Rajshahi

Rajshahi-6205, Bangladesh

E-mail: hossain95@yahoo.com

Submitted filename: Response to Reviewers.docx

Click here for additional data file.

30 Oct 2020

Risk factors and etiology of neonatal sepsis after hospital delivery: a case-control study in a tertiary care hospital of Rajshahi, Bangladesh

PONE-D-20-13278R2

Dear Dr. Hossain,

We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements.

Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication.

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Kind regards,

Yung-Fu Chang

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.

Reviewer #2: All comments have been addressed

**********

2. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #2: Yes

**********

3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #2: Yes

**********

4. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #2: Yes

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5. Is the manuscript presented in an intelligible fashion and written in standard English?

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Reviewer #2: Yes

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Reviewer #2: minor grammatical errors like line 357" was the significant risk factor of neonatal sepsis" should be replaced by were ,line 362/363 has typing mistakes meropenem is repeated twice ,please repace one with imipenem.

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Reviewer #2: Yes: Bhishma Pokhrel

5 Nov 2020

PONE-D-20-13278R2

Risk factors and etiology of neonatal sepsis after hospital delivery: a case-control study in a tertiary care hospital of Rajshahi, Bangladesh

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