Genome-based prediction of cross-protective, HLA-DR-presented epitopes as putative vaccine antigens for multiple species.

Pertussis, caused by , can cause debilitating respiratory symptoms, so whole-cell pertussis vaccines (wPVs) were introduced in the 1940s. However, reactogenicity of wPV necessitated the development of acellular pertussis vaccines (aPVs) that were introduced in the 1990s. Since then, until the COVID-19 pandemic began, reported pertussis incidence was increasing, suggesting that aPVs do not induce long-lasting immunity and may not effectively prevent transmission.

High post-exposure prophylaxis (PEP) uptake among household contacts of pertussis patients enrolled in a PEP effectiveness evaluation - United States, 2015-2017.

Background: Post-exposure prophylaxis (PEP) for pertussis is recommended for household contacts of pertussis cases in the United States within 21 days of exposure, but data on PEP effectiveness for prevention of secondary cases in the setting of widespread pertussis vaccination are limited. We implemented a multi-state evaluation of azithromycin PEP use and effectiveness among household contacts.

Methods: Culture- or PCR-confirmed pertussis cases were identified through surveillance.

Evaluation of Serologic Cross-Reactivity Between Dengue Virus and SARS-CoV-2 in Patients with Acute Febrile Illness - United States and Puerto Rico, April 2020-March 2021.

The diagnosis of dengue disease, caused by the dengue virus (DENV) (a flavivirus), often requires serologic testing during acute and early convalescent phases of the disease. Some symptoms of DENV infection, such as nonspecific fever, are similar to those caused by infection with SARS-CoV-2, the virus that causes COVID-19. In studies with few COVID-19 cases, positive DENV immunoglobulin M (IgM) results were reported with various serologic tests, indicating possible cross-reactivity in these tests for DENV and SARS-CoV-2 infections (1,2).

Prevalence and characterization of pertactin deficient strains in Brazil, a whole-cell vaccine country.

Many countries have reported antigenic divergence among circulating strains, mainly in those countries which introduced the acellular pertussis (aP) vaccine. This phenomenon can be seen, for example, with the recent rise of pertactin (Prn)-deficient strains, one of the antigens included in aP vaccine formulas. The whole cell pertussis (wP) vaccine has been used in Brazil since 1977 for the primary pertussis, diphtheria and tetanus immunization series.

Effect of maternal Tdap on infant antibody response to a primary vaccination series with whole cell pertussis vaccine in São Paulo, Brazil.

Background: Maternal Tetanus, diphtheria, and acellular pertussis (Tdap) vaccination provides antibody transfer to newborn infants and may affect their antibody response to the primary vaccination series. This study aimed to assess the effect of Tdap vaccination during pregnancy on infant antibody response to the whole cell pertussis (DTwP) primary series.

Methods: Plasma from 318 pregnant women (243 Tdap-vaccinated and 75 unvaccinated) and their infants (cord blood) was collected at delivery; infant blood was again collected at 2 and 7 months, before and after their primary DTwP series.

Epidemiological Correlates of Polymerase Chain Reaction Cycle Threshold Values in the Detection of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2).

Background: Detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has principally been performed through the use of real-time reverse-transcription polymerase chain reaction testing. Results of such tests can be reported as cycle threshold (Ct) values, which may provide semi-quantitative or indirect measurements of viral load. Previous reports have examined temporal trends in Ct values over the course of a SARS-CoV-2 infection.

Association between the timing of maternal vaccination and newborns' anti-pertussis toxin antibody levels.

Background: Pertussis remains an important global public health concern, despite the presence of extensive immunization programs. Incidence and severity of pertussis are typically higher in neonates and young infants. As a strategy to protect these young infants, maternal vaccination with Tdap (tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis) has been recommended in Brazil.

Genomic Survey of Bordetella pertussis Diversity, United States, 2000-2013.

We characterized 170 complete genome assemblies from clinical Bordetella pertussis isolates representing geographic and temporal diversity in the United States. These data capture genotypic shifts, including increased pertactin deficiency, occurring amid the current pertussis disease resurgence and provide a foundation for needed research to direct future public health control strategies.

Clinical evaluation and validation of laboratory methods for the diagnosis of Bordetella pertussis infection: Culture, polymerase chain reaction (PCR) and anti-pertussis toxin IgG serology (IgG-PT).

Introduction: The appropriate use of clinically accurate diagnostic tests is essential for the detection of pertussis, a poorly controlled vaccine-preventable disease. The purpose of this study was to estimate the sensitivity and specificity of different diagnostic criteria including culture, multi-target polymerase chain reaction (PCR), anti-pertussis toxin IgG (IgG-PT) serology, and the use of a clinical case definition. An additional objective was to describe the optimal timing of specimen collection for the various tests.

Screening and Genomic Characterization of Filamentous Hemagglutinin-Deficient Bordetella pertussis.

Despite high vaccine coverage, pertussis cases in the United States have increased over the last decade. Growing evidence suggests that disease resurgence results, in part, from genetic divergence of circulating strain populations away from vaccine references. The United States employs acellular vaccines exclusively, and current isolates are predominantly deficient in at least one immunogen, pertactin (Prn).

Expanding Pertussis Epidemiology in 6 Latin America Countries through the Latin American Pertussis Project.

The Latin American Pertussis Project (LAPP), established in 2009, is a collaboration between the Centers for Disease Control and Prevention, Pan American Health Organization, Sabin Vaccine Institute, and the ministries of health of 6 countries in Latin America. The project goal is to expand understanding of pertussis epidemiology in Latin America to inform strategies for control and prevention. Here we describe LAPP structure and activities.

Development of a qualitative assay for screening of Bordetella pertussis isolates for pertussis toxin production.

Bordetella pertussis infection has been increasing in the US, with reported cases reaching over 50,000 in 2012, a number last observed in the 1950s. Concurrently, B. pertussis lacking the pertactin protein, one of the immunogens included in the acellular vaccine formulations, has rapidly emerged since 2010, and has become the predominant circulating phenotype.

Pertactin-negative Bordetella pertussis strains: evidence for a possible selective advantage.

Background: A recent increase in Bordetella pertussis without the pertactin protein, an acellular vaccine immunogen, has been reported in the United States. Determining whether pertactin-deficient (PRN(-)) B. pertussis is evading vaccine-induced immunity or altering the severity of illness is needed.

Molecular epidemiology of the pertussis epidemic in Washington State in 2012.

Although pertussis disease is vaccine preventable, Washington State experienced a substantial rise in pertussis incidence beginning in 2011. By June 2012, the reported cases reached 2,520 (37.5 cases per 100,000 residents), a 1,300% increase compared with the same period in 2011.

Serodiagnosis as adjunct assay for pertussis infection in São Paulo, Brazil.

Pertussis remains an important public health problem in many countries despite extensive immunization. Cultures and real-time PCR (RT-PCR) assays are the recommended pertussis diagnostic tests, but they lack sensitivity at the later stage of the disease. This study introduces the IgG anti-pertussis toxin enzyme-linked immunosorbent assay (PT ELISA) in our routine diagnosis to improve disease burden estimation.

Epidemiologic and laboratory features of a large outbreak of pertussis-like illnesses associated with cocirculating Bordetella holmesii and Bordetella pertussis--Ohio, 2010-2011.

Background: During 9 May 2010-7 May 2011, an outbreak of pertussis-like illness (incidence, 80 cases per 100 000 persons) occurred in Franklin County, Ohio. The majority of cases were identified by IS481-directed polymerase chain reaction (PCR), which does not differentiate among Bordetella species. We sought to determine outbreak etiology and epidemiologic characteristics.

Does tetanus-diphtheria-acellular pertussis vaccination interfere with serodiagnosis of pertussis infection?

An anti-pertussis toxin (PT) IgG enzyme-linked immunosorbent assay (ELISA) was analytically validated for the diagnosis of pertussis at a cutoff of 94 ELISA units (EU)/ml. Little was known about the performance of this ELISA in the diagnosis of adults recently vaccinated with tetanus-diphtheria-acellular pertussis (Tdap) vaccine, which contains PT. The goal of this study was to determine when the assay can be used following Tdap vaccination.

Pertussis Pseudo-outbreak linked to specimens contaminated by Bordetella pertussis DNA From clinic surfaces.

Background And Objectives: We investigated a pertussis outbreak characterized by atypical cases, confirmed by polymerase chain reaction (PCR) alone at a single laboratory, which persisted despite high vaccine coverage and routine control measures. We aimed to determine whether Bordetella pertussis was the causative agent and advise on control interventions.

Methods: We conducted case ascertainment, confirmatory testing for pertussis and other pathogens, and an assessment for possible sources of specimen contamination, including a survey of clinic practices, sampling clinics for B pertussis DNA, and review of laboratory quality indicators.