scholarly journals A comparative analysis of the outcome of malaria case surveillance strategies in Sri Lanka in the prevention of re-establishment phase

2021 ◽  
Author(s):  
W. M. Kumudunayana T. de A. W Gunasekera ◽  
Risintha Premaratne ◽  
Deepika Fernando ◽  
Muzrif Munaz ◽  
M. G. Y. Piyasena ◽  
...  
Keyword(s):  
Sri Lanka ◽  
Case Reports ◽  
Individual Case ◽  
Case Detection ◽  
Malaria Surveillance ◽  
Blood Smears ◽  
Passive Case Detection ◽  
Routine Basis ◽  
Detection Strategies ◽  
Very High

Abstract Background Sri Lanka sustained its malaria-free status by implementing, among other interventions, three core case detection strategies namely Passive Case Detection (PCD), Reactive Case Detection (RACD) and Proactive Case Detection (PACD). The outcomes of these strategies were analysed in terms of their effectiveness in detecting malaria infections for the period from 2017-2019. Methods Comparisons were made between the surveillance methods and between years, based on data obtained from the national malaria database and individual case reports of malaria patients. The number of blood smears examined microscopically was used as the measure of the volume of tests conducted. The yield from each case detection method was calculated as the proportion of blood smears which were positive for malaria. Within RACD and PACD, the yield of sub categories of travel cohorts and spatial cohorts was ascertained for 2019. Results A total of 158 malaria cases were reported in 2017-2019. During this period between 666,325-725,149 blood smears were examined annually. PCD detected 95.6%, with a yield of 16.1 cases per 100,000 blood smears examined. RACD and PACD produced a yield of 11.2 and 0.3, respectively. The yield of screening the sub category of travel cohorts was very high for RACD and PACD being 806.5 and 44.9 malaria cases per 100,000 smears, respectively. Despite over half of the blood smears examined being obtained by screening spatial cohorts within RACD and PACD, the yield of both was zero over all three years. Conclusions The PCD arm of case surveillance is the most effective and, therefore, has to continue and be further strengthened as the mainstay of malaria surveillance. Focus on travel cohorts within RACD and PACD should be even greater. Screening of spatial cohorts, on a routine basis and solely because people are resident in previously malarious areas, may be wasteful, except in situations where the risk of local transmission is very high, or is imminent. These findings may apply more broadly to most countries in the post-elimination phase.

scholarly journals A comparative analysis of the outcome of malaria case surveillance strategies in Sri Lanka in the prevention of re‐establishment phase

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
W. M. Kumudunayana T. de A. W. Gunasekera ◽  
Risintha Premaratne ◽  
Deepika Fernando ◽  
Muzrif Munaz ◽  
M. G. Y. Piyasena ◽  
...  
Keyword(s):  
Sri Lanka ◽  
Case Reports ◽  
Individual Case ◽  
Case Detection ◽  
Malaria Surveillance ◽  
Blood Smears ◽  
Passive Case Detection ◽  
Routine Basis ◽  
Detection Strategies ◽  
Very High

Abstract Background Sri Lanka sustained its malaria-free status by implementing, among other interventions, three core case detection strategies namely Passive Case Detection (PCD), Reactive Case Detection (RACD) and Proactive Case Detection (PACD). The outcomes of these strategies were analysed in terms of their effectiveness in detecting malaria infections for the period from 2017 to 2019. Methods Comparisons were made between the surveillance methods and between years, based on data obtained from the national malaria database and individual case reports of malaria patients. The number of blood smears examined microscopically was used as the measure of the volume of tests conducted. The yield from each case detection method was calculated as the proportion of blood smears which were positive for malaria. Within RACD and PACD, the yield of sub categories of travel cohorts and spatial cohorts was ascertained for 2019. Results A total of 158 malaria cases were reported in 2017–2019. During this period between 666,325 and 725,149 blood smears were examined annually. PCD detected 95.6 %, with a yield of 16.1 cases per 100,000 blood smears examined. RACD and PACD produced a yield of 11.2 and 0.3, respectively. The yield of screening the sub category of travel cohorts was very high for RACD and PACD being 806.5 and 44.9 malaria cases per 100,000 smears, respectively. Despite over half of the blood smears examined being obtained by screening spatial cohorts within RACD and PACD, the yield of both was zero over all three years. Conclusions The PCD arm of case surveillance is the most effective and, therefore, has to continue and be further strengthened as the mainstay of malaria surveillance. Focus on travel cohorts within RACD and PACD should be even greater. Screening of spatial cohorts, on a routine basis and solely because people are resident in previously malarious areas, may be wasteful, except in situations where the risk of local transmission is very high, or is imminent. These findings may apply more broadly to most countries in the post-elimination phase.

scholarly journals A Comparative Analysis of the Outcome of Malaria Case Surveillance Strategies in Sri Lanka in the Prevention of Re-establishment Phase

2020 ◽  
Author(s):  
W. M. Kumudunayana T. de A. W Gunasekera ◽  
Risintha Premaratne ◽  
Deepika Fernando ◽  
Muzrif Munaz ◽  
M. G. Y. Piyasena ◽  
...  
Keyword(s):  
Sri Lanka ◽  
Case Reports ◽  
Individual Case ◽  
Case Detection ◽  
Malaria Surveillance ◽  
Blood Smears ◽  
Passive Case Detection ◽  
Routine Basis ◽  
Detection Strategies ◽  
Very High

Abstract BackgroundSri Lanka sustained its malaria-free status by implementing, among other interventions, three core case detection strategies. The outcomes of these strategies - namely Passive Case Detection (PCD) and, under the overall strategy of Active Case Detection (ACD), Reactive Case Detection (RACD) and Proactive Case Detection (PACD) - were analysed in terms of their effectiveness in detecting malaria infections for the period from 2017-2019.MethodsComparisons were made between the surveillance methods and between years, based on data obtained from the national malaria database and individual case reports of malaria patients. The number of blood smears examined microscopically was used as the measure of the volume of tests conducted. The yield from each case detection method was calculated as the proportion of blood smears which were positive for malaria. Within RACD and PACD, the yield of sub categories of travel cohorts and spatial cohorts was ascertained for 2019.Results A total of 158 malaria cases were reported in 2017-2019, during which between 666,325-725,149 blood smears were examined each year: PCD detected 95.6%, with a yield of 16.1 cases per 100,000 blood smears examined, making it the most effective case detection strategy, while RACD and PACD produced a yield of 11.2 and 0.3 respectively. The yield of screening the sub category of travel cohorts was very high for RACD and PACD being 806.5 and 44.9 malaria cases per 100,000 smears respectively. Despite over half of the blood smears examined being obtained by screening spatial cohorts within RACD and PACD, the yield of both was zero over all three years.Conclusions The PCD arm of case surveillance is the most effective, and therefore, has to continue and be further strengthened as the mainstay in malaria surveillance. Focus on travel cohorts within RACD and PACD should be even greater. Screening of spatial cohorts, on a routine basis and solely because people are resident in previously malarious areas, may be wasteful, except in situations where the risk of local transmission is very high, or is imminent.

Effectiveness of passive case detection for imported malaria in a hospital setting in Sri Lanka during the prevention of re-introduction phase of malaria

2018 ◽  
Author(s):  
Priyani Dharmawardena ◽  
Risintha Premaratne ◽  
Kamini Mendis ◽  
Rajitha Wickemasinghe ◽  
Chaturaka Rodrigo ◽  
...  
Keyword(s):  
Sri Lanka ◽  
Hospital Setting ◽  
Imported Malaria ◽  
Case Detection ◽  
Passive Case Detection

scholarly journals Performance of passive case detection for malaria surveillance: results from nine countries in Mesoamerica and the Dominican Republic

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Diego Rios-Zertuche ◽  
Keith H. Carter ◽  
Katie Panhorst Harris ◽  
Max Thom ◽  
Maria Paola Zúñiga-Brenes ◽  
...  
Keyword(s):  
Dominican Republic ◽  
Malaria Elimination ◽  
Health Facilities ◽  
Suspected Case ◽  
Case Detection ◽  
Malaria Surveillance ◽  
Detection Rates ◽  
Travel History ◽  
Passive Case Detection ◽  
Malaria Test

Abstract Background In malaria elimination settings, available metrics for malaria surveillance have been insufficient to measure the performance of passive case detection adequately. An indicator for malaria suspected cases with malaria test (MSCT) is proposed to measure the rate of testing on persons presenting to health facilities who satisfy the definition of a suspected malaria case. This metric does not rely on prior knowledge of fever prevalence, seasonality, or external denominators, and can be used to compare detection rates in suspected cases within and between countries, including across settings with different levels of transmission. Methods To compute the MSCT, an operational definition for suspected malaria cases was established, including clinical and epidemiological criteria. In general, suspected cases included: (1) persons with fever detected in areas with active malaria transmission; (2) persons with fever identified in areas with no active transmission and travel history to, or residence in areas with active transmission (either national or international); and (3) persons presenting with fever, chills and sweating from any area. Data was collected from 9 countries: Belize, Colombia (in areas with active transmission), Costa Rica, Dominican Republic, El Salvador, Guatemala, Honduras, Nicaragua, and Panama (September–March 2020). A sample of eligible medical records for 2018 was selected from a sample of health facilities in each country. An algorithm was constructed to assess if a malaria test was ordered or performed for cases that met the suspected case definition. Results A sample of 5873 suspected malaria cases was obtained from 239 health facilities. Except for Nicaragua and Colombia, malaria tests were requested in less than 10% of all cases. More cases were tested in areas with active transmission than areas without cases. Travel history was not systematically recorded in any country. Conclusions A statistically comparable, replicable, and standardized metric was proposed to measure suspected malaria cases with a test (microscopy or rapid diagnostic test) that enables assessing the performance of passive case detection. Cross-country findings have important implications for malaria and infectious disease surveillance, which should be promptly addressed as countries progress towards malaria elimination. Local and easy-to-implement tools could be implemented to assess and improve passive case detection.

scholarly journals Modelling Cost-Effectiveness of Syphilis Detection Strategies In Prisoners: Exploratory Exercise In A Chilean Male Prison

2020 ◽  
Author(s):  
Carla Castillo-Laborde ◽  
Pedro Gajardo ◽  
Manuel Nájera-De Ferrari ◽  
Isabel Matute ◽  
Macarena Hirmas-Adauy ◽  
...  
Keyword(s):  
Cost Effectiveness ◽  
Mathematical Modelling ◽  
Rapid Test ◽  
Cost Effective ◽  
Current Situation ◽  
Case Detection ◽  
Active Case ◽  
Passive Case Detection ◽  
Rapid Tests ◽  
Detection Strategies

Abstract BACKGROUND: Syphilis, together with other sexually transmitted infections, remains a global public health problem that is far from being controlled. People deprived of liberty are one of the vulnerable population. Control activities in prisons rely mostly on passive case detection, despite the existence of affordable alternatives that would allow switching to active case-finding strategies. Our objective was to develop a mathematical modelling framework for cost-effectiveness evaluation, from a health system perspective, of different approaches using rapid tests for the detection of syphilis in inmates' populations and to explore the results based on a Chilean male prison population. Methods: A compartmental model was developed to characterize the transmission dynamics of syphilis inside a prison with the ongoing strategy (passive case detection, with VRDL + FTA-ABS), considering the entrance and exit of inmates over a 40 year period. The model allows to simulate the implementation of a reverse algorithm for the current situation (rapid test + VDRL), different screening strategies (entry point, massive periodically; both with rapid test + VDRL) and treatment of detected cases. The parameters for the exploratory exercise were obtained from systematic searches of indexed and grey literature and field work (EQ-5D questionnaire application and key actors interviews). Probabilistic sensitivity analysis was conducted to account for uncertainty in relevant parameters. RESULTS: The proposed framework allows the evaluation of different detection strategies. In this study, all the strategies were cost-effective in the baseline scenario when considering an ICER threshold of 1 Chilean GDP per capita (US$15,000). The strategies most likely to be cost-effective (over 80% probability) were: current situation with reverse algorithm, entry point screening and mass screening every two years; the latter was the most effective, achieving the lowest prevalence (0.7% and 1.7% over the period versus the 3% prevalence in the current situation).CONCLUSIONS: Mathematical modelling that considers the performance of different test and detection strategies might be a powerful tool for decision making. The exploratory results show the efficiency of adopting both the use of the rapid tests and to perform active case detection to significantly reduce the burden of syphilis in Chilean prisons in the near future.

scholarly journals Modelling Cost-Effectiveness Of Syphilis Detection Strategies In Prisoners: Exploratory Exercise In A Chilean Male Prison

2020 ◽  
Author(s):  
Carla Castillo-Laborde ◽  
Pedro Gajardo ◽  
Manuel Nájera-De Ferrari ◽  
Isabel Matute ◽  
Macarena Hirmas-Adauy ◽  
...  
Keyword(s):  
Cost Effectiveness ◽  
Mathematical Modelling ◽  
Rapid Test ◽  
Cost Effective ◽  
Current Situation ◽  
Case Detection ◽  
Active Case ◽  
Passive Case Detection ◽  
Rapid Tests ◽  
Detection Strategies

Abstract BACKGROUND: Syphilis, together with other sexually transmitted infections, remains a global public health problem that is far from being controlled. People deprived of liberty are one of the vulnerable population. Control activities in prisons rely mostly on passive case detection, despite the existence of affordable alternatives that would allow switching to active case-finding strategies. Our objective was to develop a mathematical modelling framework for cost-effectiveness evaluation, from a health system perspective, of different approaches using rapid tests for the detection of syphilis in inmates' populations and to explore the results based on a Chilean male prison population. Methods: A compartmental model was developed to characterize the transmission dynamics of syphilis inside a prison with the ongoing strategy (passive case detection, with VRDL + FTA-ABS), considering the entrance and exit of inmates over a 40 year period. The model allows simulation of the implementation of a reverse algorithm for the current situation (rapid test + VDRL), different screening strategies (entry point, massive periodically; both with rapid test + VDRL) and treatment of detected cases. The parameters for the exploratory exercise were obtained from systematic searches of indexed and grey literature and field work (EQ-5D questionnaire application and key actors interviews). Probabilistic sensitivity analysis was conducted to account for uncertainty in relevant parameters. RESULTS: The proposed framework allows the evaluation of different detection strategies. In this study, all the strategies were cost-effective in the baseline scenario when considering an ICER threshold of 1 Chilean GDP per capita (US$15,000). The strategies most likely to be cost-effective (over 80% probability) were: current situation with reverse algorithm, entry point screening and mass screening every two years; the latter was the most effective, achieving the lowest prevalence (0.7% and 1.7% over the period versus the 3% prevalence in the current situation).CONCLUSIONS: Mathematical modelling that considers the performance of different test and detection strategies could be a useful tool for decision making. The exploratory results show the efficiency of adopting both the use of the rapid tests and performing active case detection to significantly reduce the burden of syphilis in Chilean prisons in the near future.

scholarly journals Modelling Cost-Effectiveness of Syphilis Detection Strategies in Prisoners: Exploratory Exercise in a Chilean Male Prison

2021 ◽  
Author(s):  
Carla Castillo-Laborde ◽  
Pedro Gajardo ◽  
Manuel Nájera-De Ferrari ◽  
Isabel Matute ◽  
Macarena Hirmas-Adauy ◽  
...  
Keyword(s):  
Cost Effectiveness ◽  
Mathematical Modelling ◽  
Rapid Test ◽  
Cost Effective ◽  
Current Situation ◽  
Case Detection ◽  
Active Case ◽  
Passive Case Detection ◽  
Rapid Tests ◽  
Detection Strategies

Abstract BACKGROUND: Syphilis, together with other sexually transmitted infections, remains a global public health problem that is far from controlled. People deprived of liberty are a vulnerable population. Control activities in prisons rely mostly on passive case detection, despite the existence of affordable alternatives that would allow switching to active case-finding strategies. Our objective was to develop a mathematical modelling framework for cost-effectiveness evaluation, from a health system perspective, of different approaches using rapid tests for the detection of syphilis in inmates' populations and to explore the results based on a Chilean male prison population. Methods: A compartmental model was developed to characterize the transmission dynamics of syphilis inside a prison with the ongoing strategy (passive case detection, with VRDL + FTA-ABS), considering the entrance and exit of inmates over a 40 year period. The model allows simulation of the implementation of a reverse algorithm for the current situation (rapid test + VDRL), different screening strategies (entry point, massive periodically; both with rapid test + VDRL) and treatment of detected cases. The parameters for the exploratory exercise were obtained from systematic searches of indexed and grey literature and field work (EQ-5D questionnaire application and key actors interviews). Probabilistic sensitivity analysis was conducted to account for uncertainty in relevant parameters. RESULTS: The proposed framework allows the evaluation of different detection strategies. In this study, all the strategies were cost-effective in the baseline scenario when considering an ICER threshold of 1 Chilean GDP per capita (US$15,000). The strategies most likely to be cost-effective (over 80% probability) were: current situation with reverse algorithm, entry point screening and mass screening every two years; the latter was the most effective, achieving the lowest prevalence (0.7% and 1.7% over the period versus the 3% prevalence in the current situation).CONCLUSIONS: Mathematical modelling that considers the performance of different tests and detection strategies could be a useful tool for decision making. The exploratory results show the efficiency of adopting both the use of the rapid tests and performing active case detection to significantly reduce the burden of syphilis in Chilean prisons in the near future.

scholarly journals Active and passive case detection strategies for the control of leishmaniasis in Bangladesh

2014 ◽  
Vol 4 (1) ◽  
pp. 15-21 ◽  
Author(s):  
A. K. Das ◽  
A. D. Harries ◽  
S. G. Hinderaker ◽  
R. Zachariah ◽  
B. Ahmed ◽  
...  
Keyword(s):  
Case Detection ◽  
Passive Case Detection ◽  
Detection Strategies

scholarly journals Modelling Cost-Effectiveness of Syphilis Detection Strategies in Prisoners: Exploratory Exercise in a Chilean Male Prison

2020 ◽  
Author(s):  
Carla Castillo-Laborde ◽  
Pedro Gajardo ◽  
Manuel Nájera-De Ferrari ◽  
Isabel Matute ◽  
Macarena Hirmas-Adauy ◽  
...  
Keyword(s):  
Cost Effectiveness ◽  
Mathematical Modelling ◽  
Rapid Test ◽  
Cost Effective ◽  
Current Situation ◽  
Case Detection ◽  
Active Case ◽  
Passive Case Detection ◽  
Rapid Tests ◽  
Detection Strategies

Abstract BACKGROUND: Syphilis, together with other sexually transmitted infections, remains a global public health problem that is far from being controlled. People deprived of liberty are one of the vulnerable population. Control activities in prisons rely mostly on passive case detection, despite the existence of affordable alternatives that would allow switching to active case-finding strategies. Our objective was to develop a mathematical modelling framework for cost-effectiveness evaluation, from a health system perspective, of different approaches using rapid tests for the detection of syphilis in inmates' populations and to explore the results based on a Chilean male prison population. Methods: A compartmental model was developed to characterize the transmission dynamics of syphilis inside a prison with the ongoing strategy (passive case detection, with VRDL + FTA-ABS), considering the entrance and exit of inmates over a 40 year period. The model allows simulation of the implementation of a reverse algorithm for the current situation (rapid test + VDRL), different screening strategies (entry point, massive periodically; both with rapid test + VDRL) and treatment of detected cases. The parameters for the exploratory exercise were obtained from systematic searches of indexed and grey literature and field work (EQ-5D questionnaire application and key actors interviews). Probabilistic sensitivity analysis was conducted to account for uncertainty in relevant parameters. RESULTS: The proposed framework allows the evaluation of different detection strategies. In this study, all the strategies were cost-effective in the baseline scenario when considering an ICER threshold of 1 Chilean GDP per capita (US$15,000). The strategies most likely to be cost-effective (over 80% probability) were: current situation with reverse algorithm, entry point screening and mass screening every two years; the latter was the most effective, achieving the lowest prevalence (0.7% and 1.7% over the period versus the 3% prevalence in the current situation).CONCLUSIONS: Mathematical modelling that considers the performance of different tests and detection strategies could be a useful tool for decision making. The exploratory results show the efficiency of adopting both the use of the rapid tests and performing active case detection to significantly reduce the burden of syphilis in Chilean prisons in the near future.

scholarly journals Modelling cost-effectiveness of syphilis detection strategies in prisoners: exploratory exercise in a Chilean male prison

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Carla Castillo-Laborde ◽  
Pedro Gajardo ◽  
Manuel Nájera-De Ferrari ◽  
Isabel Matute ◽  
Macarena Hirmas-Adauy ◽  
...  
Keyword(s):  
Cost Effectiveness ◽  
Mathematical Modelling ◽  
Rapid Test ◽  
Cost Effective ◽  
Current Situation ◽  
Case Detection ◽  
Active Case ◽  
Passive Case Detection ◽  
Rapid Tests ◽  
Detection Strategies

Abstract Background Syphilis, together with other sexually transmitted infections, remains a global public health problem that is far from controlled. People deprived of liberty are a vulnerable population. Control activities in prisons rely mostly on passive case detection, despite the existence of affordable alternatives that would allow switching to active case-finding strategies. Our objective was to develop a mathematical modelling framework for cost-effectiveness evaluation, from a health system perspective, of different approaches using rapid tests for the detection of syphilis in inmates' populations and to explore the results based on a Chilean male prison population. Methods A compartmental model was developed to characterize the transmission dynamics of syphilis inside a prison with the ongoing strategy (passive case detection, with VRDL + FTA-ABS), considering the entrance and exit of inmates over a 40 year period. The model allows simulation of the implementation of a reverse algorithm for the current situation (rapid test + VDRL), different screening strategies (entry point, massive periodically; both with rapid test + VDRL) and treatment of detected cases. The parameters for the exploratory exercise were obtained from systematic searches of indexed and grey literature and field work (EQ-5D questionnaire application and key actors interviews). Probabilistic sensitivity analysis was conducted to account for uncertainty in relevant parameters. Results The proposed framework allows the evaluation of different detection strategies. In this study, all the strategies were cost-effective in the baseline scenario when considering an ICER threshold of 1 Chilean GDP per capita (US$15,000). The strategies most likely to be cost-effective (over 80% probability) were: current situation with reverse algorithm, entry point screening and mass screening every two years; the latter was the most effective, achieving the lowest prevalence (0.7% and 1.7% over the period versus the 3% prevalence in the current situation). Conclusions Mathematical modelling that considers the performance of different tests and detection strategies could be a useful tool for decision making. The exploratory results show the efficiency of adopting both the use of the rapid tests and performing active case detection to significantly reduce the burden of syphilis in Chilean prisons in the near future.

Sign in / Sign up

Export Citation Format

Share Document