Genomic analysis unveils genome degradation events and gene flux in the emergence and persistence of S. Paratyphi A lineages

Paratyphoid fever caused by S. Paratyphi A is endemic in parts of South Asia and Southeast Asia. The proportion of enteric fever cases caused by S. Paratyphi A has substantially increased, yet only limited data is available on the population structure and genetic diversity of this serovar. We examined the phylogenetic distribution and evolutionary trajectory of S. Paratyphi A isolates collected as part of the Indian enteric fever surveillance study "Surveillance of Enteric Fever in India (SEFI)." In the study period (2017-2020), S. Paratyphi A comprised 17.6% (441/2503) of total enteric fever cases in India, with the isolates highly susceptible to all the major antibiotics used for treatment except fluoroquinolones. Phylogenetic analysis clustered the global S. Paratyphi A collection into seven lineages (A-G), and the present study isolates were distributed in lineages A, C and F. Our analysis highlights that the genome degradation events and gene acquisitions or losses are key molecular events in the evolution of new S. Paratyphi A lineages/sub-lineages. A total of 10 hypothetically disrupted coding sequences (HDCS) or pseudogenes-forming mutations possibly associated with the emergence of lineages were identified. The pan-genome analysis identified the insertion of P2/PSP3 phage and acquisition of IncX1 plasmid during the selection in 2.3.2/2.3.3 and 1.2.2 genotypes, respectively. We have identified six characteristic missense mutations associated with lipopolysaccharide (LPS) biosynthesis genes of S. Paratyphi A, however, these mutations confer only a low structural impact and possibly have minimal impact on vaccine effectiveness. Since S. Paratyphi A is human-restricted, high levels of genetic drift are not expected unless these bacteria transmit to naive hosts. However, public-health investigation and monitoring by means of genomic surveillance would be constantly needed to avoid S. Paratyphi A serovar becoming a public health threat similar to the S. Typhi of today.

Enteral Iron Supplementation in Preterm or Low Birth Weight Infants: A Systematic Review and Meta-analysis

BACKGROUND AND OBJECTIVES

Iron is needed for growth and development of infants globally, but preterm and low birth weight (LBW) infants are at risk for severe iron deficiencies. To assess the effect of enteral iron supplementation on mortality, morbidity, growth, and neurodevelopment outcomes in preterm or LBW infants fed human milk. Secondary objectives were to assess the effect on biomarkers and dose and timing.

METHODS

Data sources include PubMed, Embase and Cochrane Library databases to March 16, 2021. Study Selection includes controlled or quasi experimental study designs. Two reviewers independently extracted data.

RESULTS

Eight trials (eleven reports; 1093 participants, 7 countries) were included. No trials reported mortality. At latest follow-up, there was little effect on infection (very low certainty evidence, 4 studies, 401 participants, relative risk [RR] 0.98, 95% confidence interval [95% CI] 0.56 to 1.73, I2 = 0.00%) and necrotising enterocolitis (3 studies, 375 participants, RR 1.47, 95% CI 0.68 to 3.20, I2 = 0.00%). There was an increase in linear growth (length) (moderate certainty evidence, 3 studies, 384 participants, mean difference 0.69 cm, 95% CI 0.01 to 1.37, I2 = 0%) but little effect on weight, head circumference, or cognitive development. There was an improvement in anemia (moderate certainty evidence, 2 studies, 381 participants, RR 0.25, 95% CI 0.10 to 0.62, I2 = 0.00%) but no effect on serum ferritin. Limitations include heterogeneity in the included studies.

CONCLUSIONS

There are important benefits for human milk-fed preterm and LBW infants from enteral iron supplementation. However, more randomized control trials are required to improve the certainty of evidence.

Enteral Vitamin D Supplementation in Preterm or Low Birth Weight Infants: A Systematic Review and Meta-analysis

BACKGROUND AND OBJECTIVES

Many preterm and low birth weight (LBW) infants have low vitamin D stores. The objective of this study was to assess effects of enteral vitamin D supplementation compared with no vitamin D supplementation in human milk fed preterm or LBW infants.

METHODS

Data sources include Cochrane Central Register of Controlled Trials, Medline, and Embase from inception to March 16, 2021. The study selection included randomized trials. Data were extracted and pooled with fixed and random-effects models.

RESULTS

We found 3 trials (2479 participants) that compared vitamin D to no vitamin D. At 6 months, there was increase in weight-for-age z-scores (mean difference 0.12, 95% confidence interval [CI] 0.01 to 0.22, 1 trial, 1273 participants), height-for-age z-scores (mean difference 0.12, 95% CI 0.02 to 0.21, 1 trial, 1258 participants); at 3 months there was decrease in vitamin D deficiency (risk ratio 0.58, 95% CI 0.49 to 0.68, I2=58%, 2 trials, 504 participants) in vitamin D supplementation groups. However, there was little or no effect on mortality, any serious morbidity, hospitalization, head circumference, growth to 6 years and neurodevelopment. The certainty of evidence ranged from very low to moderate. Fourteen trials (1969 participants) assessed dose and reported no effect on mortality, morbidity, growth, or neurodevelopment, except on parathyroid hormone and vitamin D status. No studies assessed timing. Limitations include heterogeneity and small sample size in included studies.

CONCLUSIONS

Enteral vitamin D supplementation improves growth and vitamin D status in preterm and LBW infants.

Enteral Multiple Micronutrient Supplementation in Preterm and Low Birth Weight Infants: A Systematic Review and Meta-analysis

OBJECTIVES

To assess effects of supplementation with 3 or more micronutrients (multiple micronutrients; MMN) compared to no MMN in human milk-fed preterm and low birth weight (LBW) infants.

RESULTS

Data on a subgroup of 414 preterm or LBW infants from 2 randomized controlled trials (4 reports) were included. The certainty of evidence ranged from low to very low. For growth outcomes in the MMN compared to the non-MMN group, there was a small increase in weight-for-age (2 trials, 383 participants) and height-for-age z-scores (2 trials, 372 participants); a small decrease in wasting (2 trials, 398 participants); small increases in stunting (2 trials, 399 participants); and an increase in underweight (2 trials, 396 participants). For neurodevelopment outcomes at 78 weeks, we found small increases in Bayley Scales of Infant Development, Version III (BISD-III), scores (cognition, receptive language, expressive language, fine motor, gross motor) in the MMN compared to the non-MMN group (1 trial, 27 participants). There were no studies examining dose or timing of supplementation.

CONCLUSIONS

Evidence is insufficient to determine whether enteral MMN supplementation to preterm or LBW infants who are fed mother's own milk is associated with benefit or harm. More trials are needed to generate evidence on mortality, morbidity, growth, and neurodevelopment.

Enteral Calcium or Phosphorus Supplementation in Preterm or Low Birth Weight Infants: a Systematic Review and Meta-analysis

OBJECTIVES

To assess effects of calcium or phosphorous supplementation compared with no supplementation in human milk-fed preterm or low birth weight infants.

METHODS

Data sources include Cochrane Central Register of Controlled Trials, Medline and Embase. We included Randomized controlled trials (RCTs) and non-randomized trials (quasi-randomized).

RESULTS

Three studies (4 reports; 162 infants) were included. At latest follow-up (38 weeks), there was reduction in osteopenia (3 studies, 159 participants, relative risk 0.68, 95% confidence interval [CI] 0.46-0.99). At latest follow-up (6 weeks), there was no effect on weight (1 study, 40 participants, mean difference [MD] 138.50 g, 95% CI -82.16 to 359.16); length (1 study, 40 participants, MD 0.77 cm, 95% CI -0.93 to 2.47); and head circumference (1 study, 40 participants, MD 0.33 cm, 95% CI -0.30 to 0.96). At latest follow-up, there was no effect on alkaline phosphatase (55 weeks) (2 studies, 122 participants, MD -126.11 IU/L, 95% CI -298.5 to 46.27, I2 = 73.4%); serum calcium (6 weeks) (1 study, 40 participants, MD 0.54 mg/dL, 95% CI -0.19 to 1.27); and serum phosphorus (6 weeks) (1 study, 40 participants, MD 0.07 mg/dL, 95% CI -0.22 to 0.36). The certainty of evidence ranged from very low to low. No studies reported on mortality and neurodevelopment outcomes.

CONCLUSIONS

The evidence is insufficient to determine whether enteral supplementation with calcium or phosphorus for preterm or low birth weight infants who are fed mother's own milk or donor human milk is associated with benefit or harm.

Estimating the Impact of COVID-19 Pandemic Related Lockdown on Utilization of Maternal and Perinatal Health Services in an Urban Neighborhood in Delhi, India

Objective

To estimate utilization of maternal, perinatal healthcare services after the lockdown was implemented in response to the COVID-19 pandemic compared to the period before.

Methods

This study conducted in Dakshinpuri, an urban neighborhood in Delhi, reports data over a 13-month period which includes the period “before lockdown” i.e., October 1, 2019 to March 21, 2020 and “after lockdown” i.e., March 22 to November 5, 2020. The period “after lockdown” included the lockdown phase (March 22 to May 31, 2020) and unlock phase (June 1 to November 5, 2020). Mothers delivered during this period in the study area were interviewed using semi-structured questionnaires. In-depth interviews (IDIs) were conducted in a subsample to understand the experiences, challenges, and factors for underutilization of healthcare services.

Findings

The survey covered a total population of 21,025 in 4,762 households; 199 eligible mothers (mean age 27.4 years) were interviewed. In women who delivered after lockdown against before lockdown, adjusted odds of having >2 antenatal care visits in the third trimester was 80% lower (aOR 0.2, 95% CI 0.1–0.5); proportion of institutional deliveries was lower (93 vs. 97%); exclusive breastfeeding during first 6 months of birth (64.5 vs. 75.7%) and health worker home visitation within 6 weeks of birth (median, 1 vs. 3 visits) were substantially lower. Fear of contracting COVID-19, poor quality of services, lack of transportation and financial constraints were key issues faced by mothers in accessing health care. More than three-fourth (81%) of the mothers reported feeling down, depressed or hopeless after lockdown. The major factors for stress during lockdown was financial reasons (70%), followed by health-related concerns.

Conclusion

COVID-19 pandemic-related lockdown substantially affected maternal and perinatal healthcare utilization and service delivery.

ROTAVAC® does not interfere with the immune response to childhood vaccines in Indian infants: A randomized placebo controlled trial

A phase III randomized double-blind placebo-controlled trial was conducted in the urban neighborhoods of Delhi to assess whether Oral Rotavirus Vaccine ROTAVAC^® interferes with the immune response to childhood vaccines when coadministered. Infants aged 6 weeks were randomized to receive three doses of either ROTAVAC^® or placebo along with childhood vaccines: Oral Polio Vaccine and vaccines against Diphtheria, Pertussis, Tetanus, Hepatitis B and Haemophilus influenza type b given as Pentavalent at 6, 10, 14 weeks of age. Blood specimens were collected from all infants at baseline and 4 weeks post dose 3 to assess the immune response to antigens in Oral Polio Vaccine, Pentavalent and ROTAVAC^® vaccines. Non-inferiority of immune response to all vaccine components of the childhood vaccines when ROTAVAC^® was administered concurrently was demonstrated. Non-inferior immune responses to childhood vaccines were evaluated based on the seroprotective levels of antibodies against polio types 1, 2, and 3, Diphtheria toxoid, Tetanus toxoid, Haemophilus influenza type b anti- polyribosyl ribitol phosphate antibodies and Hepatitis B antibodies; and the Geometric Mean Concentration for Pertussis. The proportion of infants who seroconverted (≥4 fold rise) was 38.6% in the ROTAVAC^® group and 12.2% in the placebo group. The frequency and severity of immediate adverse events, adverse events and serious adverse events were similar in both groups. None of the five reported deaths were considered to be related to the ROTAVAC^® and no case of intussusception meeting Brighton Diagnostic Certainty Level I criteria was reported.

This study demonstrated that ROTAVAC^® can be safely administered with childhood vaccines without interfering with the immune response to the antigens contained in these vaccines.