The epidemiology of mumps in the UK: a preliminary study of virus transmission, herd immunity and the potential impact of immunization

SUMMARYMathematical models and statistical analyses of epidemiological data are employed to assess the potential impact of mass vaccination on the incidences of cases of mumps infection and cases of mumps related complications. The analyses reveal that in the United Kingdom the average age at infection with the mumps virus is currently between 6–7 years and that the inter-epidemic period of the infection is approximately 3 years. The critical level of vaccine uptake to eliminate mumps virus transmission is predicted to be approximately 85% of each cohort of boys and girls by the age of 2 years. Analyses of published data show that the risk of complication arising from mumps infection is markedly age- and sex-related. Model predictions suggest that the incidence of orchitis will be increased, over the level pertaining prior to mass vaccination, by levels of vaccine uptake (by 2 years of age) that are less than 70% of each yearly cohort of boys and girls. Moderate (over 00%) to high (75%) levels of vaccine uptake, however, are predicted to reduce the overall incidence of cases of mumps related complications (especially those with CNS involvement).

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Pertussis in England and Wales: an investigation of transmission dynamics and control by mass vaccination

Proceedings of the Royal Society of London Series B Biological Sciences ◽

10.1098/rspb.1989.0022 ◽

1989 ◽

Vol 236 (1284) ◽

pp. 213-252 ◽

Cited By ~ 48

Keyword(s):

Mathematical Models ◽

Vaccine Efficacy ◽

Case Reports ◽

Mass Vaccination ◽

Vaccine Uptake ◽

Transmission Dynamics ◽

England And Wales ◽

Epidemic Period ◽

The Impact ◽

Induced Immunity

The epidemiology of pertussis and its prospects for control by mass vaccination in England and Wales are investigated by analyses of longitudinal records on incidence and vaccine uptake, and horizontal data on age-stratified case reports. Mathematical models of the transmission dynamics of the infection that incorporate loss of natural and vaccine-induced immunity plus variable vaccine efficacy are developed, and their predictions compared with observed trends. Analyses of case reports reveal that the individual force of infection is age dependent, with peak transmission in the 5- to 10-year-old age class. A model incorporating this age dependency, along with partial vaccine efficacy and loss of vaccine-induced immunity, generates predicted patterns that best mirror observed trends since mass vaccination was inaugurated in 1957 in England and Wales. Model projections accurately mirror the failure of mass vaccination to increase the inter-epidemic period of the infection (three years) over that pertaining before control. The analysis suggests that this is due to the impact of partial vaccine efficacy. Projected trends to not accurately reflect the low levels of pertussis incidence reported between epidemics in the periods of high vaccine uptake. This is thought to arise from a combination of factors, including loss of natural and vaccine induced immunity, biases in case reporting (where reporting efficiency is positively associated with the incidence of pertussis), and seasonal variations in transmission. Model predictions suggest that the vaccination of 88% of each birth cohort before the age of 1 year will eliminate bacterial transmission, provided the vaccine confers lifelong protection against infection. If vaccine-induced immunity is significantly less than lifelong (or if vaccination fails to protect all its recipients) repeated cohort immunization is predicted to be necessary to eliminate transmission. Future research needs are discussed, and emphasis is placed on the need for more refined data on vaccine efficacy, the duration of natural and vaccine-induced immunity and the incidence of clinical pertussis and subclinical infections (perhaps by the development of reliable serological tests). Future mathematical models will need especially to incorporate seasonality in transmission.

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Impact of vaccination and birth rate on the epidemiology of pertussis: a comparative study in 64 countries

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2010.0994 ◽

2010 ◽

Vol 277 (1698) ◽

pp. 3239-3245 ◽

Cited By ~ 68

Author(s):

H. Broutin ◽

C. Viboud ◽

B. T. Grenfell ◽

M. A. Miller ◽

P. Rohani

Keyword(s):

Birth Rate ◽

Vaccine Coverage ◽

Strong Association ◽

Herd Immunity ◽

Public Health Problem ◽

Recruitment Rate ◽

Vaccine Uptake ◽

Important Public Health Problem ◽

Epidemic Period ◽

The Impact

Bordetella pertussis infection remains an important public health problem worldwide despite decades of routine vaccination. A key indicator of the impact of vaccination programmes is the inter-epidemic period, which is expected to increase with vaccine uptake if there is significant herd immunity. Based on empirical data from 64 countries across the five continents over the past 30–70 years, we document the observed relationship between the average inter-epidemic period, birth rate and vaccine coverage. We then use a mathematical model to explore the range of scenarios for duration of immunity and transmission resulting from repeat infections that are consistent with empirical evidence. Estimates of pertussis periodicity ranged between 2 and 4.6 years, with a strong association with susceptible recruitment rate, defined as birth rate × (1 − vaccine coverage). Periodicity increased by 1.27 years on average after the introduction of national vaccination programmes (95% CI: 1.13, 1.41 years), indicative of increased herd immunity. Mathematical models suggest that the observed patterns of pertussis periodicity are equally consistent with loss of immunity that is not as rapid as currently thought, or with negligible transmission generated by repeat infections. We conclude that both vaccine coverage and birth rate drive pertussis periodicity globally and that vaccination induces strong herd immunity effects. A better understanding of the role of repeat infections in pertussis transmission is critical to refine existing control strategies.

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Targeting COVID-19 Vaccine Hesitancy in Minority Populations in the US: Implications for Herd Immunity

Vaccines ◽

10.3390/vaccines9050489 ◽

2021 ◽

Vol 9 (5) ◽

pp. 489

Author(s):

James E. K. Hildreth ◽

Donald J. Alcendor

Keyword(s):

Ethnic Minorities ◽

Healthcare System ◽

Herd Immunity ◽

Virus Transmission ◽

Healthcare Research ◽

Vaccine Uptake ◽

Vaccine Hesitancy ◽

Culturally Competent ◽

Vaccine Trials ◽

The Us

There has been a continuous underrepresentation of minorities in healthcare research and vaccine trials, along with long-standing systemic racism and discrimination that have been fueling the distrust of the healthcare system among these communities for decades. The history and legacy of racial injustices and negative experiences within a culturally insensitive healthcare system have greatly contributed to vaccine hesitancy among ethnic minorities. COVID-19 vaccine hesitancy will impact vaccine uptake in the US, subsequently hindering the establishment of herd immunity (75–85% of the population vaccinated) to mitigate SARS-CoV-2 infection and transmission. Information targeting underserved racial/ethnic minorities in the US in a culturally competent manner has been lacking. This information is crucial for educating these communities about COVID-19 vaccines and their distribution as well as dispelling misinformation regarding vaccine trials, safety, and efficacy. This lack of education has greatly contributed to COVID-19 vaccine hesitancy and will increase disparities in vaccine uptake. Moreover, timely vaccinations are also essential to curtailing virus transmission and the emergence of SARS-CoV-2 variants that may evade the immune response produced by the three existing COVID-19 vaccines.

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Short report: Introduction of chikungunya virus ECSA genotype into the Brazilian Midwest and its dispersion through the Americas

PLoS Neglected Tropical Diseases ◽

10.1371/journal.pntd.0009290 ◽

2021 ◽

Vol 15 (4) ◽

pp. e0009290

Author(s):

Elaine Cristina de Oliveira ◽

Vagner Fonseca ◽

Joilson Xavier ◽

Talita Adelino ◽

Ingra Morales Claro ◽

...

Keyword(s):

Chikungunya Virus ◽

Herd Immunity ◽

Virus Transmission ◽

Epidemiological Data ◽

Short Report ◽

South American ◽

Mato Grosso ◽

Gradual Accumulation ◽

Spatio Temporal

Since introduction into Brazil in 2014, chikungunya virus (CHIKV) has presented sustained transmission, although much is unknown about its circulation in the midwestern states. Here, we analyze 24 novel partial and near complete CHIKV genomes from Cuiaba, an urban metropolis located in the Brazilian midwestern state of Mato Grosso (MT). Nanopore technology was used for sequencing CHIKV complete genomes. Phylogenetic and epidemiological approaches were used to explore the recent spatio-temporal evolution and spread of the CHIKV-ECSA genotype in Midwest Brazil as well as in the Americas. Epidemiological data revealed a reduction in the number of reported cases over 2018–2020, likely as a consequence of a gradual accumulation of herd-immunity. Phylogeographic reconstructions revealed that at least two independent introductions of the ECSA lineage occurred in MT from a dispersion event originating in the northeastern region and suggest that the midwestern Brazilian region appears to have acted as a source of virus transmission towards Paraguay, a bordering South American country. Our results show a complex dynamic of transmission between epidemic seasons and suggest a possible role of Brazil as a source for international dispersion of the CHIKV-ECSA genotype to other countries in the Americas.

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Efficacy of the CoronaVac® Vaccine in a Region of the Colombian Amazon, Was Herd Immunity Achieved?

10.21203/rs.3.rs-593936/v1 ◽

2021 ◽

Author(s):

Salim Mattar ◽

Héctor Serrano-Coll ◽

Hollman Miller ◽

Camilo Guzmán ◽

Ricardo Rivero ◽

...

Keyword(s):

Developing Countries ◽

Observational Study ◽

Urban Population ◽

Herd Immunity ◽

Severe Infection ◽

Mass Vaccination ◽

Mild Disease ◽

Immunization Strategies ◽

Mass Immunization ◽

Colombian Amazon

Abstract Introduction. Currently, more than 1.8 billion doses of SARS-CoV-2 vaccines have been applied worldwide. However, some developing countries are still a long way from achieving herd immunity through vaccination. In some territories, such as the Colombian Amazon, mass immunization strategies have been implemented with the CoronaVac® vaccine. Due to its proximity to Brazil, where one of the variants of interest of SARS-CoV-2 circulates. Objective. To determine the efficacy of the CoronaVac® vaccine in a population of the Colombian Amazon. Methods. Between February 24, 2021, and May 19, 2021, a descriptive observational study was carried out in which a population of individuals over 18 years of age immunized with two doses of the CoronaVac® vaccine was evaluated. The study site was in the municipality of Mitú, Vaupés, in southeastern Colombia, a region located in the Amazon bordering Brazil. Results. 87% of the urban population of the Mitú municipality were vaccinated with CoronaVac®. To date, 2.1% of vaccinated individuals have become ill, and only 0.1% of these require hospitalization. No deaths attributable to COVID-19 have been reported among vaccinated individuals, and the vaccine has shown 97% efficacy against mild disease and 100% against severe infection. Conclusions. The herd immunity achieved through mass vaccination in this population has made it possible to reduce the rate of complicated cases and mortality from COVID-19 in this region of the Colombian Amazon.

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COVID-19 Vaccination of HCWs in the First Phase of a Large-Scale Mass Vaccination Program within a Healthcare System

Antimicrobial Stewardship & Healthcare Epidemiology ◽

10.1017/ash.2021.20 ◽

2021 ◽

Vol 1 (S1) ◽

pp. s11-s11

Author(s):

Kimberly Korwek ◽

E. Jackie Blanchard ◽

Julia Moody ◽

Katherine Lange ◽

Ryan Sledge ◽

...

Keyword(s):

Human Resources ◽

Healthcare Workers ◽

Large Scale ◽

Rapid Development ◽

Vaccination Strategy ◽

State Level ◽

Mass Vaccination ◽

Vaccine Uptake ◽

Vaccination Program ◽

Vaccination Rates

Background: The approval of the first SARS-COV-2 vaccines for COVID-19 were accompanied by unprecedented efforts to provide vaccination to healthcare workers and first responders. More information about vaccine uptake in this group is needed to better refine and target educational messaging. Methods: HCA Healthcare used federal guidance and internal experience to create a systemwide mass vaccination strategy. A closed point-of-dispensing (POD) model was developed and implemented. The previously developed enterprise-wide emergency operations strategy was adapted and implemented, which allowed for rapid development of communications and operational processes. A tiering strategy based on recommendations from the National Academies was used in conjunction with human resources data to determine vaccine eligibility for the first phase of vaccination. A comprehensive data and reporting strategy was built to connect human resources and vaccine consent data for tracking vaccination rates across the system. Results: Vaccination of employed and affiliated colleagues began December 15, 2020, and was made available based on state-level release of tiers. Within the first 6 weeks, in total, 203,544 individuals were eligible for vaccine based on these criteria. Of these, 181,282 (89.1%) consented to and received vaccine, 19,788 (9.7%) declined, and 2,474 (1.2%) indicated that they had already been vaccinated. Of those eligible, the highest acceptance of vaccine was among the job codes of specialists and professionals (n = 7,914 total, 100% consent), providers (n = 23,335, 99.6%,), and physicians (n = 3,218, 98.4%). Vaccine was most likely to be declined among job codes of clerical and other administrative (n = 12,889 total, 80.1% consent), clinical specialists and professionals (n = 22,853, 81.0%,) and aides, orderlies and technicians (n = 17,803, 82.6%,). Registered nurses made up the largest eligible population (n = 56,793), and 89.5% of those eligible consented to receive vaccination. Average age among those who consented was slightly older (48.3 years) than those that declined (44.7 years), as was length of employment tenure (6.9 vs 5.0 years). Conclusion: A large-scale, closed POD, mass vaccination program was able to vaccinate nearly 200,000 healthcare workers for SARS-CoV-2 in 6 weeks. This program was implemented in acute-care sites across 20 different US states, and it was able to meet the various state-level requirements for management of processes, product, and required reporting. The development of a standardized strategy and custom, centralized monitoring and reporting facilitated insight into the characteristics of early vaccine adopters versus those who decline vaccination. These data can aid in the refining and targeting of educational materials and messaging about the SARS-CoV-2 vaccine.Funding: NoDisclosures: None

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Collective immunity to SARS-CoV-2 of Moscow residents during the COVID-19 epidemic period

Infekcionnye bolezni ◽

10.20953/1729-9225-2020-4-8-16 ◽

2020 ◽

Vol 18 (4) ◽

pp. 8-16

Author(s):

A.Yu. Popova ◽

◽

E.B. Yezhlova ◽

A.A. Melnikova ◽

E.E. Andreeva ◽

...

Keyword(s):

Herd Immunity ◽

Age Groups ◽

Asymptomatic Infection ◽

Administrative District ◽

Cultural Workers ◽

Population Immunity ◽

The North ◽

First Case ◽

Epidemic Period ◽

Structure Of Population

The coronavirus disease pandemic (COVID-19) was announced by WHO in February 2020. In Moscow, the first case of the disease was detected on March 2, 2020 in a man who arrived from Italy. Two weeks after the first case, there was an exponential increase in the number of cases. The incidence peaked in the 19th week of the year, followed by a steady decline, lasting 16 weeks. Objective. To investigate the level and structure of population immunity to the SARS-CoV-2 virus among the population of Moscow against the background of the incidence of COVID-19. Patients and methods. The study of population immunity of Moscow residents to SARS-CoV-2 was carried out in the period from July 1, 2020 to July 30, 2020 against the background of stabilization of the incidence rate. The work was conducted as part of the first stage of the Rospotrebnadzor project to assess population immunity to the SARS-CoV-2 virus among the population of the Russian Federation, taking into account the protocol recommended by WHO. Volunteers for the study were selected by the method of questioning and randomization. The results of the survey of 2688 people were included in the analysis. The number of volunteers in all age groups was 384–385 people. The content of specific IgG to the SARS-CoV-2 nucleocapsid was determined by the enzyme-linked immunosorbent assya using a kit produced by FBIS SRCAMB according to the manufacturer's instructions. Results. During the survey of volunteers it was found that the share of seroprevalent residents of Moscow was 22.1%. By age groups, the highest proportion of seroprevalent was found among children aged 14–17 years (44.6%), the lowest (15.9%) – among people aged 18–29 years. Seroprevalence had no gender differences. The lowest level of herd immunity was revealed in the North-Western Administrative District (16.8%), the highest – in the South-Eastern Administrative District, as well as in the Troitsky and Novomoskovsky Administrative Districts of Moscow (in both, 24.1%). The smallest number of seropositive persons was among cultural workers (5.8%), the largest – among medical workers (27.0%). In the presence of contacts with patients with COVID-19, the probability of seroconversion increases by 1.5 times, and among convalescing persons COVID-19 antibodies were detected in 60.0% of cases. The proportion of people with asymptomatic infection among seropositive residents was 82.4%. Conclusion. The results obtained make it possible to characterize the population immunity of Moscow residents and are essential for the planning and implementation of anti-epidemic measures during the incidence of COVID-19. Key words: coronaviruses, SARS-CoV-2, seroprevalence, population, COVID-19

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Introduction to pertussis transmission and epidemiological dynamics

Pertussis ◽

10.1093/oso/9780198811879.003.0001 ◽

2018 ◽

pp. 6-25

Author(s):

Pejman Rohani ◽

Samuel V. Scarpino

Keyword(s):

Control Strategies ◽

Age Distribution ◽

Population Level ◽

Vaccine Uptake ◽

Effective Control ◽

Transmission Potential ◽

Epidemic Period ◽

The Impact ◽

Pertussis Epidemiology

Resolving the long-term, population-level consequences of changes in pertussis epidemiology, arising from bacterial evolution, shifts in vaccine-induced immunity, or changes in surveillance, are key challenges for devising effective control strategies. This chapter reviews some of the key features of pertussis epidemiology, together with the underlying epidemiological principles that set the context for their interpretation. These include the relationship between the age distribution of cases and pertussis transmission potential, the impact of vaccine uptake on incidence, periodicity and age incidence, as well as spatially explicit recurrent pertussis epidemics and associated extinction frequency. This review highlights some of the predictable and consistent aspects of pertussis epidemiology (e.g. the systematic increase in the inter-epidemic period with the introduction of whole-cell vaccines) and a number of important heterogeneities, including variations in contemporary patterns of incidence and geographic spread.

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Manic syndromes in old age

10.1093/med/9780199644957.003.0044 ◽

2013 ◽

Cited By ~ 1

Author(s):

Akshya Vasudev

Keyword(s):

Bipolar Disorder ◽

Clinical Presentation ◽

Age Of Onset ◽

Late Onset ◽

Epidemiological Data ◽

The Elderly ◽

Published Data ◽

Management Options ◽

Pharmacological Management ◽

Heterogenous Group

Manic syndromes in the elderly are different from those seen in the younger bipolar population. They are a heterogenous group but can probably be divided into two main groups based on age of onset of the illness: late onset bipolar disorder (LOB) and early onset bipolar disorder (EOB). This chapter elaborates on differences in these two groups based on epidemiological data findings, clinical presentation, aetiopathogenesis and management. Latest concepts with regards to the vascular mania hypothesis, neuroimaging findings, cognitive impairment in bipolar disorder are also dealt with. A critical review of pharmacological management options is also provided with reference to recently published data on mood stabilisers, antipsychotic and antidepressant usage for this age group.

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Application of a fast and cost-effective ‘three-in-one’ MMR ELISA as a tool for surveying anti-MMR humoral immunity: the Hungarian experience

Epidemiology and Infection ◽

10.1017/s0950268819002280 ◽

2020 ◽

Vol 148 ◽

Author(s):

K. Böröcz ◽

Z. Csizmadia ◽

Á. Markovics ◽

N. Farkas ◽

J. Najbauer ◽

...

Keyword(s):

Humoral Immunity ◽

Low Cost ◽

Herd Immunity ◽

Reference Method ◽

Population Level ◽

Cost Effective ◽

Published Data ◽

Mmr Vaccine ◽

Igg Antibody ◽

Automated Platform

Abstract In Hungary, between February 2017 and July 2019, 70 confirmed measles cases were reported, raising questions about the adequacy of population-level immunity. Although the assumed vaccination coverage is ≥99%, in a recent study, we detected potential gaps in the anti-measles humoral immunity. In Hungary, according to a decree by the Ministry of Public Welfare, beginning from 2021, the healthcare provider should conduct a serosurvey of anti-measles protection levels of healthcare professionals. To facilitate the compliance with this requirement, we developed a quick ‘three-in-one’ or ‘triple’ MMR (measles, mumps and rubella) indirect ELISA (IgG); an assay format that is currently not available commercially. High throughput applicability of the ‘three-in-one’ ELISA was verified using 1736 sera from routine laboratory residual samples, using an automated platform (Siemens BEP 2000 Advance). Assay verification was performed by comparing the full antigen repertoire-based ‘target’ assay with in-house ‘control’ assays using recombinant viral antigen coatings, and by validated commercially available kits. Indirect immunofluorescence was used as an independent reference method. Data were analysed using OriginLab, IBM SPSS, RStudio and MedCalc. In case of measles, we combined our current results with previously published data (Ntotal measles = 3523). Evaluation of anti-mumps and anti-rubella humoral antibody levels was based on the measurement of 1736 samples. The lowest anti-measles seropositivity (79.3%) was detected in sera of individuals vaccinated between 1978 and 1987. Considering the antigen-specific seropositivity ratios of all samples measured, anti-measles, -mumps and -rubella IgG antibody titres were adequate in 89.84%, 91.82% and 92.28%, respectively. Based on the virus-specific herd immunity threshold (HIT) values (HITMeasles = 92–95%, HITMumps = 75–86%, HITRubella = 83–86), it can be stated that regarding anti-measles immunity, certain age clusters of the population may have inadequate levels of humoral immunity. Despite the potential gaps in herd immunity, the use of MMR vaccine remains an effective and low-cost approach for the prevention of measles, mumps and rubella infections.

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