Clinical characteristics and pertussis costs in cases reported to epidemiological services and cases detected in household contacts in Catalonia (Spain)

Burden of Pertussis in Adults Aged 50 Years and Older: A Retrospective Database Study in England

INTRODUCTION

Pertussis, a highly infectious respiratory disease caused by Bordetella pertussis, affects people of all ages. Older adults are particularly susceptible to its severe outcomes and complications.

METHODS

In this retrospective cohort study, the incidence rate of pertussis among individuals aged ≥ 50 years was assessed during 2009-2018 using Clinical Practice Research Datalink and Hospital Episode Statistics databases, United Kingdom. Health care resource utilisation (HCRU) and direct medical costs (DMCs) were compared between patients with a pertussis diagnosis and propensity score-matched controls (matched on demographic and clinical variables).

RESULTS

Among 5,222,860 individuals, 1638 had a pertussis diagnosis (incidence rate: 5.8 per 100,000 person-years; 95% confidence interval 5.5-6.0). Baseline (- 18 to - 6 months) HCRU and DMC were similar among 1480 pertussis patients and 1480 matched controls. However, there were increases in HCRU in the pertussis vs. matched cohort around the pertussis diagnosis (from months - 6 to - 1 to 5-11). The most notable increases (pertussis vs. controls) were in the rates of general practitioner (GP)/nurse visits (4.7-fold), clinical assessments (4.1-fold), and accident and emergency visits (3.0-fold) during the month before diagnosis and GP/nurse visits during the 2 months after diagnosis (2.5-fold) (all p < 0.001). DMCs were significantly higher in the pertussis cohort (p < 0.001). Total excess DMC in the pertussis cohort during months - 1 to + 11 was £318 per patient.

CONCLUSION

A pertussis diagnosis among adults aged ≥ 50 years resulted in significant increases in HCRU and DMC across several months around diagnosis. These results highlight the need for increased awareness of pertussis infection among adults aged ≥ 50 years and suggest that pertussis booster doses among this population should be considered.

Exploring the nasopharyngeal microbiota composition in infants with whooping cough: A test-negative case-control study

Purpose

The purpose of this study was to characterize the nasopharyngeal microbiota of infants with possible and confirmed pertussis compared to healthy controls.

Methods

This prospective study included all infants <1 year with microbiologically confirmed diagnosis of pertussis attended at a University Hospital over a 12-month period. For each confirmed case, up to 2 consecutive patients within the same age range and meeting the clinical case definition of pertussis but testing PCR-negative were included as possible cases. A third group of asymptomatic infants (healthy controls) were also included. Nasopharyngeal microbiota was characterized by sequencing the V3-V4 region of the 16S rRNA gene. Common respiratory DNA/RNA viral co-infection was tested by multiplex PCR.

Results

Twelve confirmed cases, 21 possible cases and 9 healthy controls were included. Confirmed whooping cough was primarily driven by detection of Bordetella with no other major changes on nasopharyngeal microbiota. Possible cases had limited abundance or absence of Bordetella and a distinctive microbiota with lower bacterial richness and diversity and higher rates of viral co-infection than both confirmed cases and healthy controls. Bordetella reads determined by 16S rRNA gene sequencing were found in all 12 confirmed cases (100%), 3 out of the 21 possible cases (14.3%) but in any healthy control.

Conclusion

This study supports the usefulness of 16S rRNA gene sequencing for improved sensitivity on pertussis diagnosis compared to real-time PCR and to understand other microbial changes occurring in the nasopharynx in children <1 year old with suspected whooping cough compared to healthy controls.

Healthcare Resource Consumption and Cost of Invasive Meningococcal Disease in France: A Study of the National Health Insurance Database

Introduction

Invasive meningococcal disease (IMD) is an uncommon but serious infectious disease. Its economic burden is known to be high but is poorly characterised. The objective of this study was to determine costs, as captured in the healthcare claims database, incurred by all patients hospitalised for IMD in France over a 6-year period.

Methods

This case–control study was performed using the French national public health insurance database (SNDS). Cases comprised all individuals hospitalised with acute IMD in France between 2012 and 2017 inclusive. For each case, three controls were identified, matched for age, gender and region of residence. All healthcare resource consumption by cases and controls during the follow-up period was documented. Costs were analysed for the index hospitalisation in cases, 1 year following the index date and then for 5 years following the index date. Costs were assigned from national tariffs. The analysis was performed from a societal perspective. IMD sequelae were identified from hospital discharge summaries.

Results

A total of 3532 cases and 10,590 controls were evaluated. The mean per capita cost of the index IMD hospitalisation was €11,256, and increased with age and with the presence of sequelae. In the year following the index date, mean per capita direct medical costs were €6564 in cases and €2890 in controls. Annual costs were €4254 in cases without sequelae, €10,799 in cases with one sequela and €20,096 in cases with more than one sequela. In the fifth year of follow-up, mean per capita costs were €2646 in cases and €1478 in controls. The excess cost in cases was principally due to the management of sequelae. Amputation, skin scarring and mental retardation generated per capita costs in excess of €20,000 in the first year and in excess of €10,000 for subsequent years.

Conclusion

The economic burden of IMD in France is high and, over the long-term, is driven by sequelae management.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40121-021-00468-w.

The burden of pertussis in older adults: what is the role of vaccination? A systematic literature review

INTRODUCTION

Pertussis (whooping cough) is a vaccine-preventable disease; however, neither natural- nor vaccine-induced protection is life-long. Although generally not severe in adults, pertussis can be associated with complications in patients with chronic conditions such as asthma or chronic obstructive pulmonary disease, and can be readily transmitted to more vulnerable populations, including neonates before they complete their primary vaccination. Furthermore, as the global population ages, the health and economic burden of the disease is expected to rise. Areas covered: A systematic literature review was conducted to ascertain the current epidemiological and financial burden of pertussis in older adults and to discuss the potential value of a booster vaccination in this population. Expert commentary: Our review indicates a considerable underestimation of the pertussis burden amongst older adults. Seroprevalence studies consistently demonstrate that the reported incidence may be much lower than the actual incidence. Tetanus toxoid-reduced diphtheria toxoid and acellular pertussis vaccines are immunogenic in older adults, induce high booster responses and are well-tolerated. There is therefore a good rationale for the advocacy of booster pertussis vaccination throughout life to prevent pertussis infection and its transmission, especially in adults aged ≥50 years.

Reduction of Direct Health Costs Associated with Pertussis Vaccination with Acellular Vaccines in Children Aged 0-9 Years with Pertussis in Catalonia (Spain)

OBJECTIVES

The aim of this study was to assess direct health costs in children with pertussis aged 0-9 years who were vaccinated, partially vaccinated, and unvaccinated during childhood, and to assess the association between pertussis costs and pertussis vaccination in Catalonia (Spain) in 2012-2013.

METHODS

Direct healthcare costs included pertussis treatment, pertussis detection, and preventive chemotherapy of contacts. Pertussis patients were considered vaccinated when they had received 4-5 doses, and unvaccinated or partially vaccinated when they had received 0-3 doses of vaccine. The Chi square test and the odds ratios were used to compare percentages and the t test was used to compare mean pertussis costs in different groups, considering a p < 0.05 as statistically significant. The correlation between pertussis costs and study variables was assessed using the Spearman's ρ, with a p < 0.05 as statistically significant. Multiple linear regression analysis (IBM-SPSS program) was used to quantify the association of pertussis vaccination and other study variables with pertussis costs.

RESULTS

Vaccinated children with pertussis aged 0-9 years had significantly lower odds ratios of hospitalizations (OR 0.02, p < 0.001), laboratory confirmation (OR 0.21, p < 0.001), and severe disease (OR 0.02, p < 0.001) than unvaccinated or partially vaccinated children with pertussis of the same age. Mean direct healthcare costs were significantly lower (p < 0.001) in vaccinated patients (€190.6) than in unvaccinated patients (€3550.8), partially vaccinated patients (€1116.9), and unvaccinated/partially vaccinated patients (€2330). Multivariable linear regression analysis showed that pertussis vaccination with 4-5 doses was associated with a non-significant reduction of pertussis costs of €107.9 per case after taking into account the effect of other study variables, and €200 per case after taking into account pertussis severity.

CONCLUSIONS

Direct healthcare costs were lower in children with pertussis aged 0-9 years vaccinated with 4-5 doses of acellular vaccines than in unvaccinated or partially vaccinated children with pertussis of the same age.

Effectiveness of acellular pertussis vaccination during childhood (<7 years of age) for preventing pertussis in household contacts 1-9 years old in Catalonia and Navarra (Spain)

Pertussis vaccination with 4-5 doses of acellular vaccines is recommended in Spain to all children at 2 months to 6 years of age. The effectiveness of the acellular pertussis vaccination was assessed in this study by comparing the incidence of secondary pertussis in vaccinated (4-5 doses) and unvaccinated or partially vaccinated (0-3 doses) household contacts 1-9 years old of confirmed cases of pertussis in Spain in 2012-13. Eighty-five percent of contacts had been vaccinated with 4-5 doses of acellular pertussis vaccines. During the 2-year study period, 64 cases of secondary pertussis were detected among 405 household contacts 1-9 years old: 47 among vaccinated and 17 among unvaccinated or partially vaccinated contacts. The effectiveness for preventing secondary pertussis, calculated as 1 minus the relative risk (RR) of secondary pertussis in vaccinated vs. unvaccinated/partially vaccinated contacts, was 50 % [95 % confidence interval (CI): 19-69 %, p < 0.01] when household contacts were vaccinated using DTaP, Tdap, hexavalent or heptavalent vaccines, and it was 51.3 % (95 % CI: 21-70 %, p < 0.01) when they were vaccinated using DTaP or TdaP vaccines. The effectiveness adjusted for age, sex, pertussis chemotherapy and type of household contact was 58.6 % (95 % CI: 17-79 %, p < 0.05) when contacts were vaccinated using available acellular vaccines, and it was 59.6 % (95 % CI: 18-80 %, p < 0.01) when they were vaccinated using DTaP vaccines. Acellular pertussis vaccination during childhood was effective for preventing secondary pertussis in household contacts 1-9 years old of pertussis cases in Catalonia and Navarra, Spain.