CDC Pregnancy Flu Line: monitoring severe illness among pregnant women with influenza

Birth Outcomes After Pertussis and Influenza Diagnosed in Pregnancy: A Retrospective, Population-Based Study

OBJECTIVE

Adverse birth outcomes and the maternal severity of influenza in pregnancy are well documented but information on pertussis is limited.

DESIGN

Population-based linkage data were collected during 2001-2016.

SETTING

New South Wales, Australia.

POPULATION OR SAMPLE

A total of 1 453 037 singleton births.

METHODS

Cox regression was used to estimate the associations between pertussis or influenza during pregnancy and birth outcomes with adjustment of covariates.

MAIN OUTCOME MEASURES

Adverse birth outcomes (preterm birth and low birth weight).

RESULTS

Among 1 453 037 singleton births over 16 years, we identified pertussis in 925 (49; 5.3% hospitalised) and influenza in 2850 (1092; 38.3% hospitalised) women during pregnancy. Cases of pertussis were similarly distributed by trimester (32% 3rd) whereas 46% of influenza cases were in the 3rd trimester. Younger age, previous birth, and being overseas-born were associated with both pertussis and influenza, whereas identifying as Aboriginal or Torres Strait Islander, hypertension or diabetes before and during pregnancy, and a number of other factors were only associated with influenza. Both pertussis and influenza in pregnancy were associated with increased risk of preterm birth (pertussis: aHR = 1.30, 95% CI 1.01-1.68; influenza: aHR = 1.56, 95% CI 1.36-1.79) and these increased risks were greater when infections in the period within 2 weeks of birth were considered (pertussis: aHR = 2.36, 95% CI 1.26-4.41; influenza: aHR = 2.29, 95% CI 1.78-2.96).

CONCLUSIONS

Maternal pertussis and influenza infections close to the time of birth were associated with adverse birth outcomes. These findings highlight the benefits of vaccination during pregnancy.

Population-based pregnancy and birth defects surveillance in the era of Zika virus

BACKGROUND

Zika virus is a newly recognized human teratogen; monitoring its impact on the birth prevalence of microcephaly and other adverse pregnancy outcomes will continue to be an urgent need in the United States and worldwide.

METHODS

When the Centers for Disease Control and Prevention (CDC) activated the Emergency Operations Center for the Zika virus outbreak response in January of 2016, public health leadership recognized that a joint, coordinated effort was required between activities focused on the effects of the infection among pregnant women and those focused on birth defects in fetuses and infants. Before the introduction of Zika virus in the Americas, population-based birth defects surveillance occurred independently of pregnancy surveillance activities.

RESULTS

The coordination of pregnancy surveillance and birth defects surveillance implemented through the CDC Zika virus response represents a paradigm shift.

CONCLUSION

Coordination of these surveillance systems provides an opportunity to capture information from both a prospective and retrospective approach. This relatively modest investment in the public health infrastructure can continue to protect pregnant women and their infants during the ongoing response to Zika virus and in the next emergent threat to maternal and child health. Birth Defects Research 109:372-378, 2017. © 2017 Wiley Periodicals, Inc.

Sex-based differences in immune function and responses to vaccination

Females typically develop higher antibody responses and experience more adverse reactions following vaccination than males. These differences are observed in response to diverse vaccines, including the bacillus Calmette-Guerin vaccine, the measles, mumps and rubella vaccine, the yellow fever virus vaccine and influenza vaccines. Sex differences in the responses to vaccines are observed across diverse age groups, ranging from infants to aged individuals. Biological as well as behavioral differences between the sexes are likely to contribute to differences in the outcome of vaccination between the sexes. Immunological, hormonal, genetic and microbiota differences between males and females may also affect the outcome of vaccination. Identifying ways to reduce adverse reactions in females and increase immune responses in males will be necessary to adequately protect both sexes against infectious diseases.

Pregnant women infected with pandemic influenza A(H1N1)pdm09 virus showed differential immune response correlated with disease severity

BACKGROUND

During pregnancy, immunological and hormonal alterations place women at increased risk for influenza-related severe illnesses including hospitalization and death. Although A(H1N1) pdm09 infection resulted in increased disease severity in pregnant women, the precise mechanisms responsible for this risk have yet to be established.

OBJECTIVES

The present study was aimed to investigate the role of host chemokines and cytokine profiles in A(H1N1) pdm09 infection regarding disease severity in pregnant women.

STUDY DESIGN

This retrospective survey examined 41 pregnant women with confirmed A(H1N1) pdm09 infection. Of them, 12 died (D), 29 survived (S), and 17 remained uninfected and served as controls (C). Antiviral response was evaluated for IFN-β expression and gene expression profiles of cytokines (TNF-α, IL-6, IL-12, TGF-β) and chemokines (IL-8, RANTES, MCP-1, IP-10), and the viral Matrix (M1) gene was quantified and normalized using the housekeeping gene product β-actin mRNA.

RESULTS

Higher IL-8 and TNF-α mRNA expression were found in D and S compared with C, while IL-6 showed higher expression in D. Interestingly, these results were associated with a decrease in the anti-inflammatory response of TGF-β mRNA and IFN-β. These alterations would lead to an imbalance in the immune response of those patients.

CONCLUSIONS

Pregnancy-related reductions in IFN-β and TGF-β expression levels and elevated levels of pro-inflammatory cytokines could explain the increased severity of infection and death of pregnant women. These findings may help improve the understanding of the high susceptibility and disease severity to influenza virus infection during pregnancy.

Technical guidelines for the application of seasonal influenza vaccine in China (2014-2015)

Influenza, caused by the influenza virus, is a respiratory infectious disease that can severely affect human health. Influenza viruses undergo frequent antigenic changes, thus could spread quickly. Influenza causes seasonal epidemics and outbreaks in public gatherings such as schools, kindergartens, and nursing homes. Certain populations are at risk for severe illness from influenza, including pregnant women, young children, the elderly, and people in any ages with certain chronic diseases.