Pertussis In Young Infants Research Articles

Tetanus, Diphtheria, and Acellular Pertussis Vaccination Coverage Among Publicly Insured Pregnant Women, U.S., 2016–2019

Vaccination with tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis vaccine during pregnancy is highly effective against Bordetella pertussis in young infants. We aimed to evaluate the uptake of maternal tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis vaccination during the recommended gestation period of 27 through 36 weeks among women enrolled in a public medical insurance plan in the U.S. In this analysis using Centers for Medicare and Medicaid Services insurance claims data, we identified women aged 15 through 49 years who delivered a live-born infant from 2016 through 2019. We identified claims for tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis vaccination to calculate the proportion of women who were vaccinated during Weeks 27 through 36 of gestation in each calendar year. We also assessed the average annual maternal tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis coverage by age group, race and ethnicity, U.S. Census region of residence, and plan type. Data were analyzed in 2021. Among 4,318,823 deliveries, the 4-year national average for tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis vaccination was 26%, improving from 22% in 2016 to 31% in 2019 (p<0.001). Within subgroups, the lowest 4-year average coverage was among women aged 15 through 18 years (22%); Black, non-Hispanic (23%) and Hispanic women (24%); those residing in the South (18%); those enrolled in a Children's Health Insurance Program plan (22%); and those covered by a fee-for-service plan (19%). Coverage increased across all subgroups from 2016 through 2019. Although maternal tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis coverage among publicly insured women in the U.S. increased from 2016 through 2019, it remained considerably lower than estimated national coverage, with notable differences by race and ethnicity.

Decay of anti-Bordetella pertussis antibodies in women of childbearing age following COVID-19 non-pharmaceutical measures

BackgroundImmunization against Bordetella pertussis during pregnancy reduces morbidity from severe pertussis in young infants via trans-placental transfer of anti-B. pertussis Immunoglobulin G (IgG). Studies have reported a near disappearance of respiratory pathogens including B. pertussis following implementation of mitigation strategies to control Coronavirus disease 2019 (COVID-19). We explored how immunity against B. pertussis changed in women of childbearing-age through the COVID-19 pandemic. MethodsPaired blood samples from females of childbearing-age collected at the beginning (May-June 2020) and nearly one year into the COVID-19 pandemic (February-May 2021) in British Columbia (BC), Canada were tested for anti-B. pertussis IgG levels. To ascertain whether early-pandemic IgG levels in 2020 reflected levels in pregnant women early in gestation, 1st trimester sera collected from age-matched healthy pregnant women in 2018 and 2019 were tested for anti-B. pertussis IgG. Levels were compared by t tests. P-value of 0.05 was assigned and statistical significance was set as p < 0.016 using Bonferroni correction. ResultsAnnual provincial B. pertussis incidences per 100,000 in BC in 2020 (3/100,000) and 2021 (<1/100,000) approximated the lowest levels since 1990. In 2021 vs. 2020, anti-pertussis toxin (PT), filamentous hemagglutinin (FHA) and pertactin (PRN) IgG levels declined in women of childbearing-age: 6.8 IU/ml (95 %CI, 4.2–10.9) vs. 8.4 IU/ml (5.1–13.9; p = 0.004); 18.8 IU/ml (10.9–32.2) vs. 23.6 IU/ml (13.2–42.1; p < 0.001); and 37.1 IU/ml (18.1–75.9) vs. 47.2 IU/ml (24.8–89.9; p = 0.092), respectively. Although all values were slightly higher, anti-PT, FHA and PRN IgG levels in women of childbearing age did not significantly differ in 2020 compared with early-gestation pregnant women in 2018–2019, 8.4 IU/ml (95% CI, 5.1–13.9) vs. 5.4 IU/ml (95% CI, 3.8–7.7; p = 0.166), 23.6 IU/ml (95% CI, 13.2–42.1) vs. 20.1 IU/ml (95% CI, 13.4–30.2; p = 0.656), and 47.2 IU/ml (24.8–89.9) vs. 17.3 IU/ml (95% CI, 10.5–28.7; p = 0.021), respectively. DiscussionB. pertussis infections should be closely monitored during the relaxing of mitigation measures for COVID-19.

Mind the Gap: The Impact of Maternal Immunization on Pertussis in Young Infants.

Mind the Gap: The Impact of Maternal Immunization on Pertussis in Young Infants.

Exchange transfusion in the management of critical pertussis in young infants: a case series.

It is proposed that severe leucocytosis mainly contributes to pulmonary hypertension by blocking pulmonary capillaries and restricting blood flow. Exchange transfusion (ET) in pertussis has been demonstrated as a safe and useful technique for depleting the leucocyte mass. We aim to discuss four cases of pertussis-induced respiratory distress and the effectiveness of ET in such a setting. We conducted a retrospective case series at the Infectious Disease Department of Children's Hospital 2 in Ho Chi Minh City, Vietnam, and included four pertussis patients that were confirmed by PCR tests on respiratory secretions, presented with severe leucocytosis and respiratory distress and required mechanical ventilation. Among the included patients, three underwent a double volume ET for leucodepletion, two of whom were discharged after the procedure with proper vitals and laboratory test results. On the other hand, one patient died despite ET, performed late in the course of the disease. Exchange transfusion was not performed in the last patient who died as well. Early ET may be a useful and rapid life-saving treatment in children with critical pertussis and severe leucocytosis before cardiopulmonary complications appear.

Pertussis (Keuchhusten)

Pertussis wird durch das gramnegative Bakterium Bordetella pertussis verursacht. Die Krankheitsmanifestationen reichen von unspezifischem Husten bis zu lebensbedrohlichen Verläufen mit Hyperleukozytose und respiratorischer Insuffizienz, v.a. bei jungen Säuglingen. Die Diagnose basiert auf klinischer Symptomatik und mikrobiologischen Nachweisverfahren. Die Therapie besteht aus Makrolidantibiotika; bei Apnoen kann Koffein versucht werden. Die Inzidenz beträgt 10–40 Fälle/100.000 Bevölkerung und Jahr, bei Säuglingen ist sie am höchsten (ca. 50), gefolgt von Jugendlichen (30–35). Mehr als 50 % der in den ersten 5 Lebensmonaten an Pertussis erkrankten Kinder werden hospitalisiert. Die Impfprävention umfasst Grundimmunisierung und regelmäßige Auffrischimpfungen mit azellulären Impfstoffen. Um schwere Verläufe bei jungen Säuglingen zu verhindern, ist die Impfung schwangerer Frauen am erfolgversprechendsten. Säuglinge geimpfter Mütter sollen zeitgerecht ab dem Alter von 2 Monaten für den Eigenschutz immunisiert werden.

Interference With Pertussis Vaccination in Infants After Maternal Pertussis Vaccination.

* Abbreviations: aP — : acellular pertussis DTaP — : diphtheria-tetanus-acellular pertussis DTwP — : diphtheria, tetanus, and whole-cell pertussis HIC — : high-income country LMICs — : low- and middle-income countries WHO — : World Health Organization Pertussis is a major public health concern. In 2014, 24 million cases and 160 000 deaths from pertussis in children <5 years were estimated worldwide, with nearly one-third of the cases occurring in Africa.1 Vaccination with an acellular pertussis (aP)–containing vaccine in pregnancy prevents severe pertussis in young infants and has been recommended in an increasing number of high-income countries (HICs). We have recently discussed optimal strategies for vaccination in pregnancy to maximize protection against infections in infancy.2 However, pertussis vaccination in pregnancy reduces infants’ primary immune responses to diphtheria-tetanus-acellular pertussis (DTaP) vaccines, leading to lower antibody levels to some pertussis antigens, when compared with infants of unvaccinated mothers.3 This is termed “interference” and has been shown primarily in studies from HICs that used DTaP formulations for infant immunization, but its clinical implications are unknown. Fewer data are available on the potential interference with diphtheria, tetanus, and whole-cell pertussis (DTwP) vaccines for infant immunization, the vaccines used almost exclusively in low- and middle-income countries (LMICs). An earlier study that we conducted in the United States revealed interference with DTwP vaccines, but not with DTaP vaccines, in infants with higher maternally derived antibody levels before primary vaccination.4 In a recent study conducted in Pakistan, the authors found no correlation between preexisting anti-pertussis antibody levels at delivery and infants’ anti-pertussis antibody levels after primary vaccination with DTwP vaccines.5 However, women in these 2 studies did … Address correspondence to Bahaa Abu-Raya, MD, British Columbia Children’s Hospital Research Institute, The University of British Columbia, 950 W 28th Ave, Vancouver, BC V5Z 4H4, Canada. E-mail: baburaya{at}bcchr.ubc.ca

Pertussis (Keuchhusten)

Pertussis wird durch das gramnegative Bakterium Bordetella pertussis verursacht. Die Krankheitsmanifestationen reichen von unspezifischem Husten bis zu lebensbedrohlichen Verläufen mit Hyperleukozytose und respiratorischer Insuffizienz, v.a. bei jungen Säuglingen. Die Diagnose basiert auf klinischer Symptomatik und mikrobiologischen Nachweisverfahren. Die Therapie besteht aus Makrolidantibiotika; bei Apnoen kann Koffein versucht werden. Die Inzidenz beträgt 10–40 Fälle/100.000 Bevölkerung und Jahr, bei Säuglingen ist sie am höchsten (ca. 50), gefolgt von Jugendlichen (30–35). Mehr als 50 % der in den ersten 5 Lebensmonaten an Pertussis erkrankten Kinder werden hospitalisiert. Die Impfprävention umfasst Grundimmunisierung und regelmäßige Auffrischimpfungen mit azellulären Impfstoffen. Um schwere Verläufe bei jungen Säuglingen zu verhindern, ist die Impfung schwangerer Frauen am erfolgversprechendsten. Säuglinge geimpfter Mütter sollen zeitgerecht ab dem Alter von 2 Monaten für den Eigenschutz immunisiert werden.

Cleft Nucleus Lymphocytosis in Young Infants with Pertussis

AbstractThis study aims to assess whether the cleft nucleus lymphocytosis could be an early promising clue for the diagnosis of pertussis in young infants. Pertussis (whooping cough) is a severe respiratory disease mainly caused by Bordetella pertussis infection and is characterized by a significant rise in the number of leukocyte and lymphocyte in infants and young children. In this study, the Bordetella pertussis DNA was detected from samples of pharyngeal swab by PCR assay. Levels of serum specific IgM against other respiratory pathogens were detected by Enzyme-linked immunosorbent assay (ELISA) assay. The routine blood test including numbers of leukocytes, lymphocytes, and platelets etc. were tested by automatic hemocyte analyzer (Sysemx XN1000). Besides, the morphology of leucocytes was observed in peripheral blood smear with microscope by Wright-Giemsa stain. Three cases of pertussis with cleft nucleus lymphocytes in young infants were discussed in in the neonatal/pediatric intensive care unit in our hospital. Leukocytosis characterized by lymphocytes, as well as thrombocytosis were observed in all patients. Our results demonstrated that cleft nucleus lymphocytosis accompanied with leukocytosis and lymphocytes would be potent assistant indicators for the early diagnosis of pertussis in young children.

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.

Dose-dependent effectiveness of acellular pertussis vaccine in infants: A population-based case-control study

BackgroundPertussis is a vaccine-preventable disease which is most severe in young infants. More than two decades after the introduction of acelluar pertussis vaccines (aPV) in national immunization programs in many countries worldwide, a resurgence of pertussis has been recognized. Suboptimal effectiveness of aPV has been blamed as one major reason but only few studies have evaluated dose-dependent vaccine effectiveness (VE) provided by aPV in current practice. MethodsWe performed a population-based retrospective case-control study by comparing pertussis immunization data of children 2.5 months to 2 years of age hospitalized for pertussis and residing in Switzerland with immunization data of a random control sample of children aged 2 years and residing in Switzerland. VE was defined as the percentage of hospitalizations avoided by number of aPV doses. It was calculated as 1-infection rate ratio (IRR)*100. IRR was calculated by dividing infection rates of vaccinated children and infection rates of unvaccinated children. To get dose specific VE,infection rates were stratified by number doses received. ResultsVE against hospitalization due to pertussis increased significantly with each consecutive aPV dose in a “3 + 1” primary course in infants: 42.1% (95% CI: 11.3–62.6), 83.9% (70.2–92.1), 98.2% (96.1–99.3), and 100% (97.9–100) after the 1st, 2nd, 3rd, and 4th dose, respectively. ConclusionAcellular pertussis vaccines continue to demonstrate protection against hospitalization due to pertussis in infants and young children. Therefore, together with advancing immunization of pregnant women and household contacts, better control of severe pertussis in young infants can be achieved by timely initiation of immunization.

Respiratory Viruses Frequently Mimic Pertussis in Young Infants.

Bordetella pertussis is prevalent among infants, but its diagnosis is complicated by the fact that its signs and symptoms overlap with respiratory viruses. Indeed, when evaluating the etiology of infants less than 1 year of age suspected of having pertussis, we found that respiratory viruses frequently mimic B. pertussis and are more likely to be the causative agent.

Antibody responses to Bordetella pertussis and other childhood vaccines in infants born to mothers who received pertussis vaccine in pregnancy-a prospective, observational cohort study from the United Kingdom.

SummaryThe maternal Tdap (tetanus, diphtheria and acellular pertussis) vaccination programme in the United Kingdom has successfully reduced cases of pertussis in young infants. In addition to prevention of pertussis cases, it is also important to investigate the persistence of maternal antibodies during infancy and the possible interference of maternal antibodies with infant responses to vaccines. We recruited mother–infant pairs from vaccinated and unvaccinated pregnancies and measured concentrations of immunoglobulin (Ig)G against pertussis toxin (PTx), filamentous haemagglutinin (FHA), pertactin (Prn), diphtheria toxin (DTx), tetanus toxoid (TTx) Haemophilus influenzae type b (Hib) and Streptococcus pneumoniae in mothers and infants at birth, and in infants at 7 weeks and at 5 months. Thirty‐one mother–infant pairs were tested. Tdap‐vaccinated women had significantly higher antibody against Tdap antigens, compared to unvaccinated women (DTx, P = 0·01; PTx, FHA, Prn and TTx, P < 0·001). All antibodies were actively transferred to the infants (transfer ratio > 1) with higher transfer of DTx (P = 0·04) and TTx (P = 0·02) antibody in Tdap‐vaccinated pregnancies compared to unvaccinated pregnancies. Infants from Tdap‐vaccinated pregnancies had significantly elevated antibodies to all antigens at birth (P < 0.001) and at 7 weeks (FHA, Prn, TTx, P < 0·001; DTx, P = 0.01; PTx, P = 0·004) compared to infants from unvaccinated pregnancies. Infants from Tdap‐vaccinated and ‐unvaccinated pregnancies had comparable antibody concentrations following primary pertussis immunization (PTx, P = 0·77; FHA, P = 0·58; Prn, P = 0·60; DTx, P = 0·09; TTx, P = 0·88). These results support maternal immunization as a method of protecting vulnerable infants during their first weeks of life.

The prevention of severe pertussis and pertussis deaths in young infants

ABSTRACTIntroduction: Today, in the developed world, virtually all deaths due to Bordetella pertussis illnesses occur in young infants.Areas Covered: Pertussis in young infants is characterized by an afebrile cough illness with coryza, apnea, seizures, cyanosis, and emesis. Severe illness is associated with high leukocyte and lymphocyte counts, rapid respiratory and cardiac rates and pneumonia. Many routine intensive care treatment procedures are detrimental: these include steroids and nitric oxide. Preventative measures include: quarantine, prophylactic antimicrobial agents and immunizations of the mother to be with Tdap between 27 and 36 weeks gestation.Expert Opinion: Infants deaths are due to the irreversible pulmonary hypertension which is caused by aggregates of leukocytes in the small vessels in the lung. The leukocytosis with lymphocytosis is due to pertussis toxin. It can be treated by exchange blood transfusions. However for this to be successful it needs to be started before shock or organ failure has occurred. To prevent pertussis in young infants, attention needs to be directed to the diagnosis and treatment of pertussis in adolescents and adults. Also important are antimicrobial prophylaxis in the infant and the immunization of mothers to be with Tdap vaccine during all pregnancies.

An Observational Study of Severe Pertussis in 100 Infants ≤120 Days of Age.

Pertussis in young infants is a unique, severe, afebrile, cough illness that is frequently fatal. All pertussis cases ≤120 days of age admitted to a pediatric intensive care unit in California between October 1, 2013, and April 25, 2015, were evaluated. Of 100 pertussis patients ≤120 days of age admitted to pediatric intensive care unit, there were 5 deaths. The white blood cell counts in the fatal cases were significantly higher than in the nonfatal cases. Thirty-four percent of patients were intubated, 18% received inotropic and/or vasoactive support, 22% received steroid, 4% received extracorporal membrane oxygenation, and 3% underwent exchange blood transfusion. The median age at the time of illness onset in the patients who died was 23 days. These data, as well as data from previous California studies, suggest updated strategies for the management of severe pertussis. These include perform serial white blood cell counts, treat all presumptive cases with azithromycin, evaluate for pulmonary hypertension, intubate and administer oxygen for apneic episodes and administer inotropic/vasoactive agents for cardiogenic shock. Do not administer steroids or nitric oxide. Criteria for exchange blood transfusion therapy for leukocytosis with lymphocytosis are suggested.

Epidemiology and Trends of Pertussis among Infants: United States, 2000–2015

BackgroundPertussis, a cyclic respiratory disease, causes the greatest morbidity and mortality among infants, particularly those too young to be vaccinated. Following a resurgence of pertussis in the 1990s, a recommendation was made in 2012 to vaccinate during every pregnancy in order to prevent infant disease. We describe pertussis trends from 2000–2015 among U.S. infants aged <1 year.MethodsWe analyzed infant pertussis cases reported through the National Notifiable Diseases Surveillance System from 2000 to 2015. Incidence rates (cases per 100,000 population) among various age groups (<2, 2– <4, 4– <6, and 6–<12 months) were calculated using National Center for Health Statistics population estimates as denominators. Negative binomial regression was used to estimate the annual average percent change with a linear trend; P < 0.05 was significant.ResultsFrom 2000 to 2015, 48,909 infant pertussis cases and 255 deaths were reported; infants aged <2 months accounted for 38.7% of cases. The age distribution of infant cases was stable from 2000 to 2009 but changed from 2010 to 2015 (Fig. 1), as the proportion of cases aged 4–<12 months increased annually on average by 4.7% (P < 0.001). Annual incidence was highest among <2 month olds; however, rates increased among older infants (Fig. 2): 7% average annual increase among infants aged 4–<6 months and 11% among infants aged 6–<12 months (P < 0.001 for each). The proportion of infants hospitalized decreased over time in each age group (P < 0.001 for all) with the largest annual average declines among 4–<6 (−5.1%) and 6–<12 month (−5.9%) olds. For all age groups, hospitalization rates were relatively stable, but non-hospitalization rates increased (P < 0.05 for all). The case–fatality ratio (CFR) was highest among <2 month olds (1.6%); CFRs decreased over time among <2 and 2–< 4 month olds (P < 0.05 for each).ConclusionPertussis incidence remains highest among infants aged <4 months, although the age distribution appears to be changing. Decreasing proportions of infants hospitalized may suggest a true decline in disease severity or an increase in reporting of less severe disease. Ongoing monitoring of infant pertussis is needed to better understand the impact of vaccinating pregnant women to prevent pertussis in young infants.Disclosures All authors: No reported disclosures.

Influence of maternal vaccination against diphtheria, tetanus, and pertussis on the avidity of infant antibody responses to a pertussis containing vaccine in Belgium

ABSTRACTMaternal antibodies induced by vaccination during pregnancy cross the placental barrier and can close the susceptibility gap to pertussis in young infants up to the start of primary immunization. As not only the quantity but also the quality of circulating antibodies is important for protection, we assessed whether maternal immunization affects the avidity of infant vaccine-induced IgG antibodies, in the frame of a prospective clinical trial on pregnancy vaccination in Belgium. Infants born from Tdap (Boostrix®) vaccinated (N = 55) and unvaccinated (N = 26) mothers were immunized with a hexavalent pertussis containing vaccine (Infanrix Hexa®) at 8, 12 and 16 weeks, followed by a fourth dose at 15 months of age. Right before and one month after this fourth vaccine dose, the avidity of IgG antibodies against diphtheria toxin (DT), tetanus toxin (TT), pertussis toxin (PT), filamentous hemagglutinin (FHA) and pertactin (Prn) was determined using 1.5 M ammonium thiocyanate as dissociating agent.In both groups, antibody avidity was moderate for TT, PT, FHA and Prn and low for DT after priming. After a fourth dose, antibody avidity increased significantly to high avidity for TT and PT, whereas it remained moderate for FHA and Prn and low for DT. The avidity correlated positively with antibody level in both study groups, yet not significantly for PT. When comparing both study groups, only PT-specific antibodies showed significantly lower avidity in infants born from vaccinated than from unvaccinated mothers after the fourth vaccine dose. The clinical significance of lower avidity of vaccine induced infant antibodies after maternal vaccination, if any, needs further investigation.

Population-Based Pertussis Incidence and Risk Factors in Infants Less Than 6 Months in Nepal.

BackgroundPertussis is estimated to cause 2 percent of childhood deaths globally and is a growing public health problem in developed countries despite high vaccination coverage. Infants are at greatest risk of morbidity and mortality. Maternal vaccination during pregnancy may be effective to prevent pertussis in young infants, but population-based estimates of disease burden in infants are lacking, particularly in low-income countries. The objective of this study was to estimate the incidence of pertussis in infants less than 6 months of age in Sarlahi District, Nepal.MethodsNested within a population-based randomized controlled trial of influenza vaccination during pregnancy, infants were visited weekly from birth through 6 months to assess respiratory illness in the prior week. If any respiratory symptoms had occurred, a nasal swab was collected and tested with a multitarget pertussis polymerase chain reaction (PCR) assay. The prospective cohort study includes infants observed between May 2011 and August 2014.ResultsThe incidence of PCR-confirmed Bordetella pertussis was 13.3 cases per 1000 infant-years (95% confidence interval, 7.7–21.3) in a cohort of 3483 infants with at least 1 day of follow-up.ConclusionsIn a population-based active home surveillance for respiratory illness, a low risk for pertussis was estimated among infants in rural Nepal. Nepal’s immunization program, which includes a childhood whole cell pertussis vaccine, may be effective in controlling pertussis in infants.

Pertussis in Young Infants Throughout the World.

In typical pertussis in young infants, the child will appear deceptively well; he or she will have coryza, sneezing, and a mild cough. There is no fever. This progresses to gagging, gasping, eye bulging, bradycardia, cyanosis, and vomiting. There is leukocytosis with lymphocytosis and apneic episodes. Deaths relate to leukocytosis, pulmonary hypertension, and pneumonia. The source of pertussis in young infants is most often a family member with cough illness that is not recognized as pertussis. Diagnosis is based on culture/polymerase chain reaction and leukocytosis with lymphocytosis. Treatment depends on macrolide antibiotic therapy and intubation, with assisted ventilation and oxygen. Prevention is based on prophylactic macrolide treatment, immunization starting at 6 weeks of age, and immunization of all pregnant women in the second or third trimester.

Bordetella pertussis: new concepts in pathogenesis and treatment.

The purpose of this review is to summarize and discuss recent findings and selected topics of interest in Bordetella pertussis virulence and pathogenesis and treatment of pertussis. It is not intended to cover issues on immune responses to B. pertussis infection or problems with currently used pertussis vaccines. Studies on the activities of various B. pertussis virulence factors include the immunomodulatory activities of filamentous hemagglutinin, fimbriae, and adenylate cyclase toxin. Recently emerging B. pertussis strains show evidence of genetic selection for vaccine escape mutants, with changes in vaccine antigen-expressing genes, some of which may have increased the virulence of this pathogen. Severe and fatal pertussis in young infants continues to be a problem, with several studies highlighting predictors of fatality, including the extreme leukocytosis associated with this infection. Treatments for pertussis are extremely limited, though early antibiotic intervention may be beneficial. Neutralizing pertussis toxin activity may be an effective strategy, as well as targeting two host proteins, pendrin and sphingosine-1-phosphate receptors, as novel potential therapeutic interventions. Pertussis is reemerging as a major public health problem and continued basic research is revealing information on bacterial virulence and disease pathogenesis, as well as potential novel strategies for vaccination and targets for therapeutic intervention.

Maternal and infant outcomes among women vaccinated against pertussis during pregnancy

ABSTRACTTetanus, diphtheria, and acellular pertussis (Tdap) vaccination is recommended for all women during each pregnancy to prevent pertussis in young infants. However, data on the safety of this protective measure are limited and conflicting. To assess maternal and infant outcomes associated with administration of this vaccine during pregnancy, we reviewed medical records of 1,759 women who delivered a singleton infant at a southeast Texas public hospital between November 1, 2012 and June 30, 2014. After excluding women who had inadequate prenatal care or who delivered at <27 weeks gestation, we used multivariable logistic regression analyses to compare 13 outcomes between those who did and did not receive the Tdap vaccine. We examined 6 maternal outcomes (chorioamnionitis, postpartum endometritis, preterm delivery, preterm premature rupture of membranes, induced labor, and mode of delivery) and 7 infant outcomes (low birth weight, very low birth weight, small for gestational age, 5-minute Apgar score, birth defects, and neonatal intensive care unit admission). Maternal Tdap vaccination was associated with decreased odds of cesarean delivery. No associations between maternal Tdap vaccination and infant outcomes were observed. This study demonstrates that Tdap vaccination during pregnancy does not increase the risk of adverse outcomes.