Neonatal Pertussis Research Articles

Pertussis, diphtheria, and tetanus antibodies seroprevalence in pregnant women and neonates, as a preliminary data for introduction of preconception or prenatal DTaP vaccination among Japanese society

An increasing number of countries have been introducing acellular pertussis vaccination during pregnancy for the prevention of neonatal pertussis. In response to the fact that infantile pertussis cases of 0–5 months age groups remained unchanged despite the universal vaccination program, prenatal pertussis vaccination has been a rising issue in Japan. Hence, we investigated the seroprevalence of pertussis, diphtheria, and tetanus antibodies in Japanese pregnant women and neonates, and evaluated the necessity of diphtheria-tetanus-acellular pertussis (DTaP) vaccination during the preconception or prenatal period. Maternal PT-IgG (EIA) and FHA-IgG (EIA) for the first trimester, within 1 week after delivery, and cord blood were collected, along with colostrum pertussis-IgA (ELISA), diphtheria-IgG (EIA), tetanus-IgG (EIA), and blood samples from the first trimester. The maternal seroprevalence of PT-IgG and FHA-IgG was 69 % and 75 %, respectively. All tested participants were positive for diphtheria-IgG and tetanus-IgG (100 %). First trimester PT-IgG/FHA-IgG antibody titers were significantly associated with cord blood PT-IgG/FHA-IgG titers (P < 0.001). We found that pertussis seroprevalence among pregnant Japanese women was approximately 70 %. The antibody seropositivity rate of pertussis was lower than that of diphtheria and tetanus. Fetal acquired passive immunity against pertussis is higher when the level of maternal antibody in the first trimester is sufficient. At least 30 % of study population did not reach to the threshold value to provide sufficient pertussis immunity for the neonates and themselves. The acellular pertussis vaccine (DTaP) approved in Japan lacks safety information for pregnancy, hence, a solution for prompt administration of prenatal acellular pertussis vaccination might be introducing DTaP in the preconception period.

Seroprevalence of Pertussis Antibodies and Infection Risk Among Female Medical Students

Objectives: Pertussis seroprotection among neonates depends on maternal antibodies before receiving their first childhood acellular pertussis (DTaP) vaccination. Therefore, childbearing women need to have adequate seroprotection, either before conception or during the antenatal period, to protect their neonates from contracting neonatal pertussis. Given the global rise in neonatal pertussis incidence, there is a need to address the importance of protection against this infection by promoting booster vaccinations among female medical students as a preventive measure for their future generation. This paper addresses a part of our study on the seroprevalence of anti-PT IgG antibodies in female medical students who are more prone to acquire infections from the patients during their clinical rotations. Methods: A cross-sectional study was conducted for three months by recruiting female medical students of RAK Medical and Health Sciences University, Ras Al Khaimah, UAE. The antibody levels (IgG) of pertussis (anti-PT) in blood sera of the study population were quantitated by enzyme-linked immunoassay. A 60 – 125 IU/mL titer was considered the positive titer level (p-value &lt;0.05 being statistically significant). Results: Among 90 ethnically different student participants (mean age of 21 years), forty-four percent (n=40) showed detectable titers of anti-PT IgG antibodies. Whereas fourteen percent of participants (n=13) had high positive titers above 125U/mL, four percent (n=3) showed positive titers ranging from 60-125IU/mL. Two percent (n=2) were in borderline with 55 - &lt;60IU/mL and twenty three percent (n=21) were &lt; 55IU/mL titres. The mean ± SD of IgG titers was 42 ± 74.93 IU/mL with a range of 0-267 IU/mL Conclusion: Only forty-four percent had detectable titers of anti-PT IgG antibodies, among whom fourteen percent (n=13) had high positive titers indicating recent infection. The results signify a low level of seroprotection among female medical students that emphasizes the need to promote booster vaccination for the high-risk group who work in the health profession.

Impact of childhood and maternal vaccination against diphtheria, tetanus, and pertussis in Colombia.

Background: In Latin America, there are few studies of the impact of vaccination against diphtheria, tetanus, and pertussis. We estimate the impact of infant and maternal vaccination on the incidence of these diseases in Colombia.Design and methods: an interrupted time series study analyzing the incidence before and after of vaccination with DwPT (1975-2018) and with Tdap in pregnant women (2008-2018). A segmented regression model with negative binomial distribution estimated the change in level and trend of the predicted incidence ratio after vaccination in relation to the incidence if vaccination had not been started (IRR), using a Prais Winsten regression.Results: The pertussis IRR decreased immediately after the start of childhood vaccination (0.91, p=0.51), but this was only significant (1.01, p<0.001) along with the trend per year, after the start of maternal vaccination (0.98, p<0.001). In the absence of vaccination, the incidence would not have been reduced. Neonatal tetanus had the highest rate of change with significant reduction - 1.69 - CI 95%: -2.91, -0.48). The trend after vaccination was the highest with an annual reduction of 19% (0.81, p=0.001). The change in incidence of diphtheria was significant, although slow (- 0.02 - CI 95%: -0.04, -0.004). The sustained effect in the post-vaccination period was smaller (0.95, p=0.79).Conclusion: Childhood and maternal vaccination markedly reduced the incidence of pertussis and neonatal tetanus. It is necessary to maintain optimal vaccination coverage and surveillance, within an integrated elimination plan, which prevents the resurgence of these diseases. Significance for public health Immunization and control of diseases in the process of elimination, such as neonatal tetanus and with a recent resurgence such as diphtheria and pertussis constitute a challenge for Colombia, the region, and the world. The impact of infant and maternal vaccination on reducing the incidence of diphtheria, tetanus, and pertussis in Colombia, has been reported in this study. Childhood and maternal vaccination markedly reduced the incidence of neonatal pertussis and tetanus. The change in incidence of diphtheria was significant before and after immunization, although slow. Public health efforts should focus on improving and sustaining maternal and child vaccination against diphtheria, tetanus and pertussis. Development of an integrated elimination plan is recommended for the three diseases based on the experience of neonatal tetanus.

Knowledge, Attitudes, and Practices Associated with Pertussis Vaccination during Pregnancy: Japan, 2016–2017

Neonatal pertussis can potentially cause severe complications and even death. Mothers have been most frequently identified as the source of neonatal pertussis. Approximately a dozen countries have implemented pertussis vaccination programs for pregnant women to protect neonates; however, in Japan, this has not been implemented. The aim of this questionnaire-based study was to ascertain the willingness of women to be vaccinated during pregnancy and the factors associated with willingness. The subjects were 977 pregnant women who visited either of the two selected hospitals for maternity health checks. Most of the women were in their first pregnancy (96%), and approximately half of them considered a physician to be the most reliable source of information about vaccination (481/977, 49%). "Willingness to receive pertussis vaccination" was significantly associated with the factors "no fear of receiving vaccination" (odds ratio [OR] = 3.10, 95% confidence interval [CI]: 2.21-4.34), "necessary to prevent pertussis" (OR = 8.70, 95% CI: 6.17-12.28), "effective in pregnancy" (OR = 5.46, 95% CI: 3.94-7.56), and "no concern about the side effects after vaccination" (OR = 3.03, 95% CI: 1.66-5.55). Pregnant women are likely to consider vaccination if they have a good understanding of the disease and its outcomes. Physicians are well positioned to improve knowledge and attitudes toward pertussis vaccination during pregnancy.

Neonatal pertussis: life-threatening event and outbreak prevention in the NICU

Neonatal pertussis: life-threatening event and outbreak prevention in the NICU

The second coming: The comeback of the live vaccines.

Live vaccines are gradually replaced by protein-based vaccines given the latter's better safety. But live vaccines seem to be more efficient via stimulation of the innate immune system.

Neonatal pertussis: an emerging issue of concern.

Neonatal pertussis is a resurging disease, possibly due to waning immunity in pregnant women. We report seven cases of neonatal pertussis (Bordetella pertussis DNA PCR positive) in this retrospective study conducted at a tertiary care teaching hospital in north India over eight months (March to October 2018). All except one were male infants and presented at the age of 14-30 days with paroxysmal cough in all, four had fever, four had respiratory distress, three had similar illness in the family, and two had leucocytosis. All recovered well with azithromycin. The duration of hospital stay was 5-7 days. A strong suspicion of neonatal pertussis in neonates with paroxysmal cough and similar family history should be maintained as the prognosis is excellent, if treated appropriately.

An unsuccessful case of neonatal severe pertussis pneumonia treated with extracorporeal membrane oxygenation

An unsuccessful case of neonatal severe pertussis pneumonia treated with extracorporeal membrane oxygenation

Factors affecting pregnant women's decisions regarding prenatal pertussis vaccination: A decision-making study in the nationwide Prenatal Pertussis Immunization Program in Taiwan

ObjectiveTo examine the factors affecting pregnant women's decisions to accept or decline the prenatal pertussis (Tdap) vaccination in Taiwan. Materials and methodsWe conducted a cross-sectional survey, recruiting pregnant women who had received prenatal care from eight maternity hospitals between January and December 2018. We examined the participants’ demographic characteristics, perceptions of pertussis disease risk and vaccination effectiveness, beliefs regarding vaccine information, physician recommendation, and other potential factors affecting decision-making regarding prenatal vaccination. ResultsThe complete survey response rate among eligible women was 78%. Among the participants, 74% accepted and 26% declined prenatal Tdap vaccination. Most women accepted Tdap during pregnancy because of perceived severity of pertussis in their infants, perceived effectiveness of the prenatal Tdap in preventing neonatal pertussis, and perceived safety of the prenatal Tdap vaccine for the fetus, as well as a provider's recommendation, which was the factor strongly associated with actual Tdap reception. Most of the participants who accepted Tdap vaccination during pregnancy and who believed that the Tdap vaccine could protect their infants from pertussis reported the receiving sufficient information to make an informed decision and trust in the information. By contrast, a large proportion of the participants who declined Tdap and who did not want to experience possible fetal side effects of Tdap reported not getting sufficient information to make an informed decision and a lack of trust in the information. ConclusionDeveloping a comprehensive strategy involving government policy, the health care system, public media, health professionals, and pregnant women to launch a successful campaign may improve the nationwide acceptance of the prenatal pertussis vaccination.

Applying a Constrained Optimization Portfolio Model to Aid Prioritization of Public Health Interventions in Malaysia

ObjectivesCountries have constrained healthcare budgets and must prioritize new interventions depending on health goals and time frame. This situation is relevant in the sphere of national immunization programs, for which many different vaccines are proposed, budgets are limited, and efficient choices must be made in the order of vaccine introduction. MethodsA constrained optimization (CO) model for infectious diseases was developed in which different intervention types (prophylaxis and treatment) were combined for consideration in Malaysia. Local experts defined their priority public health issues: pneumococcal disease, dengue, hepatitis B and C, rotavirus, neonatal pertussis, and cholera. Epidemiological, cost, and effectiveness data were informed from local or regionally published literature. The model aimed to maximize quality-adjusted life-year (QALY) gain through the reduction of events in each of the different diseases, under budget and intervention coverage constraints. The QALY impact of the interventions was assessed over 2 periods: lifetime and 20 years. The period of investment was limited to 15 years. ResultsThe assessment time horizon influenced the prioritization of interventions maximizing QALY gain. The incremental health gains compared with a uninformed prioritization were large for the first 8 years and declined thereafter. Rotaviral and pneumococcal vaccines were identified as key priorities irrespective of time horizon, hepatitis B immune prophylaxis and hepatitis C treatment were priorities with the lifetime horizon, and dengue vaccination replaced these with the 20-year horizon. ConclusionsCO modeling is a useful tool for making economically efficient decisions within public health programs for the control of infectious diseases by helping prioritize the selection of interventions to maximize health gain under annual budget constraints.

Impact of maternal dTpa vaccination on the incidence of pertussis in young infants.

IntroductionPertussis is an important public health problem worldwide, especially in infants. An increase in the incidence in many countries occurred after 2010, including Brazil. In 2013, dTpa vaccine was introduced in the Brazil national immunization schedule of pregnant women. The objective of this study was to evaluate the national trends in the incidence of pertussis in Brazil in children under 1 year old, and the impact of the introduction of dTpa vaccine during pregnancy.MethodsThe incidence of hospitalizations and non-hospitalized confirmed cases of pertussis in neonates (< 1 month age) and young infants (1 month—< 1 year age) were analyzed, comparing the incidence in pre maternal vaccination (2011–2013) with the post-vaccination (2015–2017). We used non-respiratory hospitalizations as comparison, during the same period. A database of the Brazilian Ministry of Health (DATASUS) was used to analyze cases from 2007 to 2017 and the subsets of 2011–2013 and 2015–2017, after Pertussis resurgence. The vaccination data was accessed through the link of the Information System of the National Immunization Program (pni.datasus.gov.br).ResultsBetween 2007 and 2017, 17,818 children under one year of age were hospitalized due to pertussis in Brazil. In the pre maternal vaccination period 2011–2013, the mean annual incidence of non-hospitalized confirmed cases of pertussis in children under 1 month was 722.2 / 100,000 and in the period of 2015–2017 the average was 377.3 / 100,000, representing a decrease of 47.7% [IRR 0.52 (0.46–0.59)]. At those periods of time, the average incidence per year for children of one month—< 1 year aged was 64.9 / 100,000 (2011–2013) and 29.3 / 100,000 (2015–2017) [IRR 0.45 (CI 0.29–0.69)].ConclusionVaccination of pregnant woman coincides with the reduction in the number of cases of pertussis in children under 1 month of age from 2015. Immunization of pregnant woman seems to have an important impact on the prevention of the disease in young infants who have not yet received their own pertussis vaccine.

Neonatal Pertussis, an Under-Recognized Health Burden and Rationale for Maternal Immunization: A Systematic Review of South and South-East Asian Countries.

Pertussis is an under-recognized cause of neonatal morbidity and mortality. To review information on the epidemiology and disease burden of neonatal pertussis in South and Southeast Asian countries, a systematic literature review of three bibliographic databases was undertaken. Peer-reviewed original studies on neonatal pertussis epidemiology and burden published since 2000, with a geographical scope limited to South and Southeast Asian countries, were included. Data were systematically extracted based on parameters defined a priori. Our findings show that the burden of neonatal pertussis and its complications is substantial. An increase in the number of pertussis cases has been noted since early 2000, ranging from 61 to 92.9% in infants 0–3 months old. The most common symptoms an infant is likely to present with are cough with or without paroxysms, cyanosis, apnea, tachypnea, difficulty in breathing and leukocytosis. In addition, it can lead to hospitalization (length of stay: 5–7 days), complications (e.g., pneumonia, seizures) and mortality ranging from 5.6 to 14.7%. Other observations indicate that diagnosis is challenging because of non-specific clinical symptoms. Specifically, for obstetricians and gynecologists, the information available for making informed decisions on the prevention of neonatal pertussis is unreliable. Maternal immunization against pertussis during late stages of pregnancy has proven to be efficacious and well tolerated. A high burden of neonatal pertussis, as well as its complications, is observed in South and Southeast Asian countries. There is a need to intensify efforts to protect this vulnerable population with maternal vaccination.Funding: GlaxoSmithKline Biologicals SAPlain Language Summary: Plain language summary available for this article. Please see Fig. 1 and the following link: https://doi.org/10.6084/m9.figshare.7951187.

Association Between Third-Trimester Tdap Immunization and Neonatal Pertussis Antibody Concentration

Immunization with tetanus, diphtheria, and acellular pertussis (Tdap) vaccine is recommended in the United States during weeks 27 through 36 of pregnancy to prevent life-threatening infant pertussis. The optimal gestation for immunization to maximize concentrations of neonatal pertussis toxin antibodies is unknown. To determine pertussis toxin antibody concentrations in cord blood from neonates born to women immunized and unimmunized with Tdap vaccine in pregnancy and optimal gestational age for immunization to maximize concentrations of neonatal antibodies. Prospective, observational, cohort study of term neonates in Houston, Texas (December 2013-March 2014). Tdap immunization during weeks 27 through 36 of pregnancy or no Tdap immunization. Primary outcome was geometric mean concentrations (GMCs) of pertussis toxin antibodies in cord blood of Tdap-exposed and Tdap-unexposed neonates and proportions of Tdap-exposed and Tdap-unexposed neonates with pertussis toxin antibody concentrations of 15 IU/mL or higher, 30 IU/mL or higher, and 40 IU/mL or higher, cutoffs representing quantifiable antibodies or levels that may be protective until the infant immunization series begins. Secondary outcome was the optimal gestation for immunization to achieve maximum pertussis toxin antibodies. Six hundred twenty-six pregnancies (mean maternal age, 29.7 years; 41% white, 27% Hispanic, 26% black, 5% Asian, 1% other; mean gestation, 39.4 weeks) were included. Three hundred twelve women received Tdap vaccine at a mean gestation of 31.2 weeks (range, 27.3-36.4); 314 were unimmunized. GMC of neonatal cord pertussis toxin antibodies from the Tdap-exposed group was 47.3 IU/mL (95% CI, 42.1-53.2) compared with 12.9 IU/mL (95% CI, 11.7-14.3) in the Tdap-unexposed group, for a GMC ratio of 3.6 (95% CI, 3.1-4.2; P < .001). More Tdap-exposed than Tdap-unexposed neonates had pertussis toxin antibody concentrations of 15 IU/mL or higher (86% vs 37%; difference, 49% [95% CI, 42%-55%]), 30 IU/mL or higher (72% vs 17%; difference, 55% [95% CI, 49%-61%]), and 40 IU/mL or higher (59% vs 12%; difference, 47% [95% CI, 41%-54%]); P < .001 for each analysis. GMCs of pertussis toxin antibodies were highest when Tdap vaccine was administered during weeks 27 through 30 and declined thereafter, reaching a peak at week 30 (57.3 IU/mL [95% CI, 44.0-74.6]). Immunization with Tdap vaccine during the third trimester of pregnancy, compared with no immunization, was associated with higher neonatal concentrations of pertussis toxin antibodies. Immunization early in the third trimester was associated with the highest concentrations.

Age-specific TLR7/8 adjuvant formulation overcomes hyporesponsiveness to neonatal acellular pertussis vaccination in a mouse model

Abstract Infection is the most common cause of mortality early in life, in large measure due to suboptimal early life vaccination strategies as compared to older age groups. New adjuvants are absolutely cardinal to further optimize current immunization approaches. However, only a few classes of adjuvants are presently incorporated in vaccines approved for human use. Recent advances in the discovery and delivery of Toll-like receptor (TLR) adjuvants have provided a new toolbox for vaccinologists. Prominent among these candidate adjuvants are synthetic small molecule TLR7/8 agonists. The development of an effective infant Bordetella pertussis vaccine is now urgent because of the resurgence of pertussis in many countries, contemporaneous and likely related to the switch from whole cell to acellular vaccines. In this context, age-specific adjuvant strategies may be key to enhance early life immunogenicity by creating a vaccine formulation that induces both robust and persistent immunity (i.e., overcome waning immunity) to B. pertussis. In the present study, we firstly optimized the a) formulation delivery system, b) stability, and c) immunologic activity of novel small molecule imidazoquinoline TLR7/8 adjuvants towards human infant leukocytes. Next, in both adult and neonatal mouse models, we demonstrate that this TLR7/8 adjuvant can overcome neonatal hyporesponsiveness to acellular pertussis vaccination by driving Th1 favoring responses to a licensed acellular vaccine (DTaP). This potent immunization strategy may be of fundamental importance in vaccine development and could represent a new paradigm for effective pertussis immunization in early life.

Tdap Vaccine Knowledge and Acceptance Rates during Pregnancy in a Los Angeles Public Teaching-Hospital Clinic [7P

INTRODUCTION: Though the prevalence of pertussis is on the rise, only 35% of pregnant women in California with public insurance reported receiving the tetanus, diphtheria and pertussis vaccine (Tdap). The Tdap vaccine has been shown to reduce the risk of neonatal pertussis by 78% if mothers received it in the third trimester. This study evaluates pregnant women’s knowledge about the Tdap and its acceptance rate during pregnancy. METHODS: After IRB approval was obtained, pregnant women receiving prenatal care at a public teaching-hospital clinic were individually interviewed from June to August 2017 about their knowledge of vaccines during pregnancy. Interviews were conducted in English or Spanish. Women who already received the Tdap were excluded. The clinic’s Tdap acceptance rate was obtained through chart review. RESULTS: Among 152 pregnant women who had not yet received the Tdap during the current pregnancy, 80(53%) had never heard of the vaccine. An additional 53(35%) had heard of the vaccine but could not identify why the vaccine was recommended in pregnancy. Forty-eight percent of these women were either undecided at the time of their interview or did not plan to get the Tdap. In contrast, the Tdap acceptance rate in the third trimester in this clinic was 84%. CONCLUSION: The majority of pregnant women in a low-income clinic have limited understanding of the importance of the Tdap during pregnancy. Interestingly, most pregnant women in this population nonetheless received the vaccine. Educational initiatives about the Tdap may improve patients' knowledge and help them become more informed in their pregnancy-related decisions.

Case report of neonatal pertussis with persistant leukemoid reaction

Case report of neonatal pertussis with persistant leukemoid reaction

Barriers for Tdap Vaccination in Pregnancy [38C

INTRODUCTION: The American College of Obstetricians and Gynecologists (the College) and the Centers for Disease Control and Prevention recommend the Tdap vaccination in the 3rd trimester of pregnancy in order to protect newborns from neonatal pertussis. The purpose of this study was to identify barriers to Tdap vaccination in pregnancy. METHODS: A multisite study was conducted at UF Health and Sacred Heart Hospitals in Florida. This study was performed in conjunction with the College's District XII Committee for Healthcare of Underserved Women. Admitted postpartum patients were offered a survey to complete on day of discharge. RESULTS: A total of 162 patients completed the survey. Forty-eight patients had private or government-sponsored insurance (TriCare, Medicare, VA) and 114 patients had Medicaid. Of private/gov-insured patients, 62.5% (30) received Tdap in the 3rd trimester compared to 21.9% (25) of patients with Medicaid. Of those who did not receive Tdap in the third trimester, 50% (6) of private/gov-insured patients cited education while 34% (21) of patients with Medicaid cited lack of access. Of patients who did not receive Tdap in the third trimester, 46.5% (53) of the Medicaid patients received it postpartum compared to 37.5% (18) of private/gov-insured patients. CONCLUSION: Patients with Medicaid insurance are less likely to receive the Tdap vaccine in the 3rd trimester than those with private or other government-sponsored insurances. In patients who did not receive Tdap, those with Medicaid cited lack of access as the primary reason they did not receive the vaccine while those with private/gov-insurance cited education-related reasons. Tdap vaccination rates in pregnancy could be increased by improving both education and access to patients.

Prevention of neonatal whooping cough in England: The essential role of the midwife

Following an increase in the incidence of whooping cough (pertussis) in the general population from 2011, coupled with neonatal pertussis mortality seen in 2012, a programme of maternal pertussis immunisation was introduced to the UK in the same year. The programme aims to provide passive immunity from birth, until active immunity can be provided through the routine immunisation programme from 8 weeks of age. Since its introduction, evaluation of the vaccine given in pregnancy has demonstrated its safety, efficacy and patient acceptability. Uptake of the vaccine has reached 70% and its continued use is an opportunity to protect newborn babies from a serious and sometimes fatal vaccine-preventable infection. Midwives should discuss pertussis immunisation with pregnant women and either signpost them to their GP to receive it or, if commissioned to do so, administer the vaccine themselves.

Pertussis: Microbiology, Disease, Treatment, and Prevention.

Pertussis is a severe respiratory infection caused by Bordetella pertussis, and in 2008, pertussis was associated with an estimated 16 million cases and 195,000 deaths globally. Sizeable outbreaks of pertussis have been reported over the past 5 years, and disease reemergence has been the focus of international attention to develop a deeper understanding of pathogen virulence and genetic evolution of B. pertussis strains. During the past 20 years, the scientific community has recognized pertussis among adults as well as infants and children. Increased recognition that older children and adolescents are at risk for disease and may transmit B. pertussis to younger siblings has underscored the need to better understand the role of innate, humoral, and cell-mediated immunity, including the role of waning immunity. Although recognition of adult pertussis has increased in tandem with a better understanding of B. pertussis pathogenesis, pertussis in neonates and adults can manifest with atypical clinical presentations. Such disease patterns make pertussis recognition difficult and lead to delays in treatment. Ongoing research using newer tools for molecular analysis holds promise for improved understanding of pertussis epidemiology, bacterial pathogenesis, bioinformatics, and immunology. Together, these advances provide a foundation for the development of new-generation diagnostics, therapeutics, and vaccines.

Is it time to vaccine pregnant woman against pertussis?

Pertussis may cause death in neonates and very young infants. In these ages pertussis vaccine has not been administered yet or infants haven't received enough doses of vaccine to protect them. Cocoon strategy have been implemented in several countries and has limited efficacy because of low coverage among households. In vaccinated pregnant women transplacental transfer of pertussis antibodies starts at 32-34 weeks of pregnancy. United Kingdom, The United States of America and afterward other countries in Europe and America have adopted this strategy. Recent British research about security and effectiveness of pertussis vaccination in pregnant women to reduce pertussis incidence and fatality cases in neonate and very young infants infant support this strategy despite the fact that controlled studies about the efficacy and security in mothers and neonates have not been published. Several studies still not published or in progress are trying to answer these two questions and to evaluate possible interference between transplacentaly transferred pertussis antibodies and infants immune response to routine vaccines. Recently WHO has recommended pertussis vaccination during pregnancy in countries where neonatal pertussis is a public health problem. Nowadays, Chilean experts discuss if pertussis vaccination of pregnant women must be adopted in our country.