[show abstract][hide abstract] ABSTRACT: Antenatal immunization of mothers with influenza vaccine increases serum antibodies and reduces the rates of influenza illness in mothers and their infants. We report the effect of antenatal immunization on the levels of specific anti-influenza IgA levels in human breast milk. (ClinicalTrials.gov identifier NCT00142389; http://clinicaltrials.gov/ct2/show/NCT00142389).
The Mother's Gift study was a prospective, blinded, randomized controlled trial that assigned 340 pregnant Bangladeshi mothers to receive either trivalent inactivated influenza vaccine, or 23-valent pneumococcal polysaccharide vaccine during the third trimester. We evaluated breast milk at birth, 6 weeks, 6 months, and 12 months, and serum at 10 weeks and 12 months. Milk and serum specimens from 57 subjects were assayed for specific IgA antibody to influenza A/New Caledonia (H1N1) using an enzyme-linked immunosorbent assay (ELISA) and a virus neutralization assay, and for total IgA using ELISA. Influenza-specific IgA levels in breast milk were significantly higher in influenza vaccinees than in pneumococcal controls for at least 6 months postpartum (p = 0.04). Geometric mean concentrations ranged from 8.0 to 91.1 ELISA units/ml in vaccinees, versus 2.3 to 13.7 ELISA units/mL in controls. Virus neutralization titers in milk were 1.2 to 3 fold greater in vaccinees, and correlated with influenza-specific IgA levels (r = 0.86). Greater exclusivity of breastfeeding in the first 6 months of life significantly decreased the expected number of respiratory illness with fever episodes in infants of influenza-vaccinated mothers (p = 0.0042) but not in infants of pneumococcal-vaccinated mothers (p = 0.4154).
The sustained high levels of actively produced anti-influenza IgA in breast milk and the decreased infant episodes of respiratory illness with fever suggest that breastfeeding may provide local mucosal protection for the infant for at least 6 months. Studies are needed to determine the cellular and immunologic mechanisms of breast milk-mediated protection after antepartum immunization.
PLoS ONE 01/2013; 8(8):e70867. · 3.73 Impact Factor
[show abstract][hide abstract] ABSTRACT: We report the immunogenicity of trivalent influenza immunization in 29 pregnant women compared with 22 nonpregnant women. We obtained blood specimens on day 0 prior to 2011-2012 influenza vaccine administration and day 28 after immunization. Hemagglutination inhibition (HAI) geometric mean titers were similar before immunization but were significantly reduced by 40%-50% in pregnant women after immunization for influenza A/California(H1N1) (P = .027) and A/Perth(H3N2) (P = .037). Postimmunization HAI titers were similar between groups for influenza B/Brisbane (P = .390). The geometric mean ratio (fold increase) for influenza A(H1N1) was nonsignificantly reduced in pregnant participants (P = .089). The percentages of participants who seroconverted and achieved seroprotection were similar between groups.
The Journal of Infectious Diseases 09/2012; · 5.85 Impact Factor
[show abstract][hide abstract] ABSTRACT: : Limited data are available in Honduras that describe the etiology and seasonality of respiratory infections, especially in rural outpatient settings. Better data may lead to improved therapeutic and preventive strategies. The goal of our study was to determine the viral etiology and seasonality of acute respiratory infections in a rural Honduran population of children.
: Prospective clinic surveillance was conducted to identify children < 5 years of age presenting with respiratory symptoms of < 5 days duration. We obtained data on age, sex, medical history, breastfeeding history, symptoms, risk factors, household setting, temperature, respiratory rate and chest examination findings. To assess the association between specific viruses and weather, regional meteorological data were collected. Nasopharyngeal samples were tested for 16 respiratory viruses using a multiplex polymerase chain reaction panel.
: From February 2010 through June 2011, 345 children < 5 years of age were enrolled; 17%, 23%, 30% and 31% were <6, 6-11, 12-23 and 24-60 months old, respectively. Including all clinics in the region, 44.5% of patients < 5 years of age with documented respiratory diagnoses were enrolled. At least 1 virus was identified in 75.4% children, of which 7.5% were coinfections; 13.3% were positive for parainfluenza, 11.9% for influenza, 8.1% for human metapneumovirus and 7.5% for respiratory syncytial virus. Rainfall correlated with parainfluenza (P < 0.0001), influenza (P < 0.0001), human metapneumovirus (P = 0.0182) and respiratory syncytial virus (P < 0.0001).
: These results suggest that the spectrum of viruses in ill, rural, Honduran children is similar to that in North and Central America, although the seasonality is typical of some tropical regions.