Nicky McCreesh
Biographic Data
| ID | 6694081 |
|---|---|
| NAME | Nicky McCreesh |
| GIVEN NAMES | Nicky |
| FAMILY NAME | McCreesh |
| SIGNATURE | MCCREESH N |
| AFFILIATIONS | London School of Hygiene & Tropical Medicine |
| ORCID | 0000-0003-1409-8531 |
| VERIFIED | Yes |
| TOTAL WORKS | 12 |
| TOTAL CITATIONS | 3 |
| AUTHOR COUNT | 12 |
| EDITOR COUNT | 0 |
| FIRST PUBLICATION YEAR | 2012 |
| LATEST PUBLICATION YEAR | 2026 |
| H-INDEX | 1 |
Projected population level impact and cost-effectiveness of clinic and community-based tuberculosis screening approaches
The South African National Department of Health have set ambitious targets to scale up TB testing, focusing primarily on clinic attendees. In the context of declining funding for TB care and prevention, the most cost-effective approaches for targeting testing should be identified. We developed a mathematical model of TB in South Africa, explicitly incorporating clinic attendance by sex and HIV/ART status. We simulated six screening approaches ove…
Within-country heterogeneity in patterns of social contact relevant for tuberculosis infection transmission, prevention, and care
Mycobacterium tuberculosis ( Mtb ) transmission is driven by variable social, environmental, and biological factors, including the number and duration of indoor contacts. Social contact data can provide information on potential transmission patterns, but is underutilised outside the field of mathematical modelling. We explore three contexts where contact data can provide valuable insights: 1) household contact tracing; 2) infection prevention and…
Qualitative system dynamics modelling to support the design and implementation of tuberculosis infection prevention and control measures in South African primary healthcare facilities
Tuberculosis infection prevention and control (TB IPC) measures are a cornerstone of policy, but measures are diverse and variably implemented. Limited attention has been paid to the health system environment, which influences successful implementation of these measures. We used qualitative system dynamics and group-model-building methods to (1) develop a qualitative causal map of the interlinked drivers of Mycobacterium tuberculosis (Mtb) transm…
Cost-effectiveness of tuberculosis infection prevention and control interventions in South African clinics
Introduction Nosocomial Mycobacterium tuberculosis ( Mtb ) transmission substantially impacts health workers, patients and communities. Guidelines for tuberculosis infection prevention and control (TB IPC) exist but implementation in many settings remains suboptimal. Evidence is needed on cost-effective investments to prevent Mtb transmission that are feasible in routine clinic environments. Methods A set of TB IPC interventions was codesigned wi…
Is neglect of self-clearance biasing TB vaccine impact estimates
BACKGROUND: (Mtb) infection remain at lifelong risk of tuberculosis disease. Recent research provides evidence that self-clearance of Mtb infection may be common, which may affect the potential impact of new vaccines that only take in infected or uninfected individuals. We explored how the inclusion of self-clearance in models of tuberculosis affects the estimates of vaccine impact in China and India. METHODS: For both countries, we calibrated a …
Estimating the contribution of transmission in primary healthcare clinics to community-wide TB disease incidence, and the impact of infection prevention and control interventions, in KwaZulu-Natal, So…
BACKGROUND: ) transmission in healthcare facilities in high burden settings. WHO guidelines on tuberculosis (TB) infection prevention and control (IPC) recommend a range of measures to reduce transmission in healthcare settings. These were evaluated primarily based on evidence for their effects on transmission to healthcare workers in hospitals. To estimate the overall impact of IPC interventions, it is necessary to also consider their impact on …
Estimating waiting times, patient flow, and waiting room occupancy density as part of tuberculosis infection prevention and control research in South African primary health care clinics
Transmission of respiratory pathogens, such as Mycobacterium tuberculosis and severe acute respiratory syndrome coronavirus 2, is more likely during close, prolonged contact and when sharing a poorly ventilated space. Reducing overcrowding of health facilities is a recognised infection prevention and control (IPC) strategy; reliable estimates of waiting times and ‘patient flow’ would help guide implementation. As part of the Umoya omuhle study, w…
Direct estimates of absolute ventilation and estimated Mycobacterium tuberculosis transmission risk in clinics in South Africa
Healthcare facilities are important sites for the transmission of pathogens spread via bioaerosols, such as Mycobacterium tuberculosis . Natural ventilation can play an important role in reducing this transmission. We aimed to measure rates of natural ventilation in clinics in KwaZulu-Natal and Western Cape provinces, South Africa, then use these measurements to estimate Mycobacterium tuberculosis transmission risk. We measured ventilation in cli…
Importance of ventilation and occupancy to Mycobacterium tuberculosis transmission rates in congregate settings
Public transport in particular may be promising targets for infection prevention and control interventions in this setting, both to reduce Mtb transmission, but also to reduce the transmission of other airborne pathogens such as measles and SARS-CoV-2
Modelling the effect of infection prevention and control measures on rate of Mycobacterium tuberculosis transmission to clinic attendees in primary health clinics in South Africa
Background Elevated rates of tuberculosis in healthcare workers demonstrate the high rate of Mycobacterium tuberculosis (Mtb ) transmission in health facilities in high-burden settings. In the context of a project taking a whole systems approach to tuberculosis infection prevention and control (IPC), we aimed to evaluate the potential impact of conventional and novel IPC measures on Mtb transmission to patients and other clinic attendees. Methods…
Evaluation of Respondent-driven Sampling
BACKGROUND: Respondent-driven sampling is a novel variant of link-tracing sampling for estimating the characteristics of hard-to-reach groups, such as HIV prevalence in sex workers. Despite its use by leading health organizations, the performance of this method in realistic situations is still largely unknown. We evaluated respondent-driven sampling by comparing estimates from a respondent-driven sampling survey with total population data. METHOD…
Community understanding of respondent-driven sampling in a medical research setting in Uganda
Respondent-driven sampling (RDS) is a widely-used variant of snowball sampling. Respondents are selected not from a sampling frame, but from a social network of existing members of the sample. Incentives are provided for participation and for the recruitment of others. Ethical and methodological criticisms have been raised about RDS. Our purpose was to evaluate whether these criticisms were justified. In this study RDS was used to recruit male ho…
Community understanding of respondent-driven sampling in a medical research setting in Uganda
Respondent-driven sampling (RDS) is a widely-used variant of snowball sampling. Respondents are selected not from a sampling frame, but from a social network of existing members of the sample. Incentives are provided for participation and for the recruitment of others. Ethical and methodological criticisms have been raised about RDS. Our purpose was to evaluate whether these criticisms were justified. In this study RDS was used to recruit male ho…
Evaluation of Respondent-driven Sampling
BACKGROUND: Respondent-driven sampling is a novel variant of link-tracing sampling for estimating the characteristics of hard-to-reach groups, such as HIV prevalence in sex workers. Despite its use by leading health organizations, the performance of this method in realistic situations is still largely unknown. We evaluated respondent-driven sampling by comparing estimates from a respondent-driven sampling survey with total population data. METHOD…
Community understanding of respondent-driven sampling in a medical research setting in Uganda
Respondent-driven sampling (RDS) is a widely-used variant of snowball sampling. Respondents are selected not from a sampling frame, but from a social network of existing members of the sample. Incentives are provided for participation and for the recruitment of others. Ethical and methodological criticisms have been raised about RDS. Our purpose was to evaluate whether these criticisms were justified. In this study RDS was used to recruit male ho…
Modelling the effect of infection prevention and control measures on rate of Mycobacterium tuberculosis transmission to clinic attendees in primary health clinics in South Africa
Background Elevated rates of tuberculosis in healthcare workers demonstrate the high rate of Mycobacterium tuberculosis (Mtb ) transmission in health facilities in high-burden settings. In the context of a project taking a whole systems approach to tuberculosis infection prevention and control (IPC), we aimed to evaluate the potential impact of conventional and novel IPC measures on Mtb transmission to patients and other clinic attendees. Methods…
Estimating the contribution of transmission in primary healthcare clinics to community-wide TB disease incidence, and the impact of infection prevention and control interventions, in KwaZulu-Natal, So…
BACKGROUND: ) transmission in healthcare facilities in high burden settings. WHO guidelines on tuberculosis (TB) infection prevention and control (IPC) recommend a range of measures to reduce transmission in healthcare settings. These were evaluated primarily based on evidence for their effects on transmission to healthcare workers in hospitals. To estimate the overall impact of IPC interventions, it is necessary to also consider their impact on …
Estimating waiting times, patient flow, and waiting room occupancy density as part of tuberculosis infection prevention and control research in South African primary health care clinics
Transmission of respiratory pathogens, such as Mycobacterium tuberculosis and severe acute respiratory syndrome coronavirus 2, is more likely during close, prolonged contact and when sharing a poorly ventilated space. Reducing overcrowding of health facilities is a recognised infection prevention and control (IPC) strategy; reliable estimates of waiting times and ‘patient flow’ would help guide implementation. As part of the Umoya omuhle study, w…
Direct estimates of absolute ventilation and estimated Mycobacterium tuberculosis transmission risk in clinics in South Africa
Healthcare facilities are important sites for the transmission of pathogens spread via bioaerosols, such as Mycobacterium tuberculosis . Natural ventilation can play an important role in reducing this transmission. We aimed to measure rates of natural ventilation in clinics in KwaZulu-Natal and Western Cape provinces, South Africa, then use these measurements to estimate Mycobacterium tuberculosis transmission risk. We measured ventilation in cli…
Importance of ventilation and occupancy to Mycobacterium tuberculosis transmission rates in congregate settings
Public transport in particular may be promising targets for infection prevention and control interventions in this setting, both to reduce Mtb transmission, but also to reduce the transmission of other airborne pathogens such as measles and SARS-CoV-2
Cost-effectiveness of tuberculosis infection prevention and control interventions in South African clinics
Introduction Nosocomial Mycobacterium tuberculosis ( Mtb ) transmission substantially impacts health workers, patients and communities. Guidelines for tuberculosis infection prevention and control (TB IPC) exist but implementation in many settings remains suboptimal. Evidence is needed on cost-effective investments to prevent Mtb transmission that are feasible in routine clinic environments. Methods A set of TB IPC interventions was codesigned wi…
Is neglect of self-clearance biasing TB vaccine impact estimates
BACKGROUND: (Mtb) infection remain at lifelong risk of tuberculosis disease. Recent research provides evidence that self-clearance of Mtb infection may be common, which may affect the potential impact of new vaccines that only take in infected or uninfected individuals. We explored how the inclusion of self-clearance in models of tuberculosis affects the estimates of vaccine impact in China and India. METHODS: For both countries, we calibrated a …
Qualitative system dynamics modelling to support the design and implementation of tuberculosis infection prevention and control measures in South African primary healthcare facilities
Tuberculosis infection prevention and control (TB IPC) measures are a cornerstone of policy, but measures are diverse and variably implemented. Limited attention has been paid to the health system environment, which influences successful implementation of these measures. We used qualitative system dynamics and group-model-building methods to (1) develop a qualitative causal map of the interlinked drivers of Mycobacterium tuberculosis (Mtb) transm…
Within-country heterogeneity in patterns of social contact relevant for tuberculosis infection transmission, prevention, and care
Mycobacterium tuberculosis ( Mtb ) transmission is driven by variable social, environmental, and biological factors, including the number and duration of indoor contacts. Social contact data can provide information on potential transmission patterns, but is underutilised outside the field of mathematical modelling. We explore three contexts where contact data can provide valuable insights: 1) household contact tracing; 2) infection prevention and…
Projected population level impact and cost-effectiveness of clinic and community-based tuberculosis screening approaches
The South African National Department of Health have set ambitious targets to scale up TB testing, focusing primarily on clinic attendees. In the context of declining funding for TB care and prevention, the most cost-effective approaches for targeting testing should be identified. We developed a mathematical model of TB in South Africa, explicitly incorporating clinic attendance by sex and HIV/ART status. We simulated six screening approaches ove…
Medicine (10 works) · Environmental health (7 works) · Tuberculosis Research and Epidemiology (7 works) · Tuberculosis (6 works) · Disease (5 works) · Infection control (5 works) · Nursing (5 works) · Population (5 works) · Psychological intervention (5 works) · Public health (5 works)