Acute Flaccid Paralysis Surveillance Performance Research Articles

Enhancing Global Poliomyelitis Surveillance Performance is Crucial for Eradication Efforts

Background: Poliomyelitis remains a significant public health challenge, with global efforts focused on its eradication. One critical strategy in this endeavor is the implementation of an acute flaccid paralysis (AFP) surveillance system, which is essential for early detection and response to poliovirus transmission. Specific Background: Despite the system's importance, there is limited evaluation of its performance, particularly in regions like Diyala province, Iraq. Knowledge Gap: Previous studies have not adequately assessed the AFP surveillance performance indicators specific to this region, necessitating a comprehensive analysis. Aims: This study aimed to evaluate the performance indicators of the AFP surveillance system in Diyala province during 2021, utilizing established World Health Organization (WHO) standards. Results: The cross-sectional study analyzed data from seven primary health care centers. Key findings revealed a Non-Polio Acute Flaccid Paralysis rate of 5.11 per 100,000 children under 15 years. Performance indicators included 100% reporting completeness, 95% timeliness of notification and investigation, and 97% stool quality for laboratory analysis. Furthermore, 97.3% of specimens reached the national laboratory within three days, demonstrating high operational efficiency. Novelty: This study is one of the first to provide a detailed evaluation of the AFP surveillance system in Diyala province, highlighting areas of strength and compliance with WHO targets. Implications: The findings underscore the effectiveness of the AFP surveillance system in this region, suggesting that its continued implementation can significantly contribute to the global eradication efforts of poliomyelitis while also serving as a model for similar evaluations in other regions. Highlights: High reporting completeness and timeliness in AFP surveillance. Non-Polio AFP rate exceeds WHO targets, indicating effective monitoring. Study supports global efforts toward poliomyelitis eradication. Keywords: Poliomyelitis, Acute Flaccid Paralysis, Surveillance System, Performance Indicators, Iraq

Surveillance To Track Progress Toward Poliomyelitis Eradication — Worldwide, 2021–2022

Since the Global Polio Eradication Initiative (GPEI) was established in 1988, the number of wild poliovirus (WPV) cases has declined by >99.9%, and WPV serotypes 2 and 3 have been declared eradicated (1). By the end of 2022, WPV type 1 (WPV1) transmission remained endemic only in Afghanistan and Pakistan (2,3). However, during 2021-2022, Malawi and Mozambique reported nine WPV1 cases that were genetically linked to Pakistan (4,5), and circulating vaccine-derived poliovirus (cVDPV) outbreaks were detected in 42 countries (6). cVDPVs are oral poliovirus vaccine-derived viruses that can emerge after prolonged circulation in populations with low immunity allowing reversion to neurovirulence and can cause paralysis. Polioviruses are detected primarily through surveillance for acute flaccid paralysis (AFP), and poliovirus is confirmed through stool specimen testing. Environmental surveillance, the systematic sampling of sewage and testing for the presence of poliovirus, supplements AFP surveillance. Both surveillance systems were affected by the COVID-19 pandemic's effects on public health activities during 2020 (7,8) but improved in 2021 (9). This report updates previous reports (7,9) to describe surveillance performance during 2021-2022 in 34 priority countries.* In 2022, a total of 26 (76.5%) priority countries met the two key AFP surveillance performance indicator targets nationally compared with 24 (70.6%) countries in 2021; however, substantial gaps remain in subnational areas. Environmental surveillance expanded to 725 sites in priority countries, a 31.1% increase from the 553 sites reported in 2021. High-quality surveillance is critical to rapidly detect poliovirus transmission and enable prompt poliovirus outbreak response to stop circulation. Frequent monitoring of surveillance guides improvements to achieve progress toward polio eradication.

Evaluation of acute flaccid paralysis surveillance performance before and during the 2014-2015 Ebola virus disease outbreak in Guinea and Liberia.

the number of wild poliomyelitis cases, worldwide, dropped from 350,000 cases in 1988 to 33 in 2018. Acute flaccid paralysis (AFP) surveillance is a key strategy toward achieving global polio eradication. The 2014 Ebola virus disease (EVD) epidemic in West Africa infected over 28,000 people and had devastating effects on health systems in Guinea, Liberia, and Sierra Leone. We sought to assess the effects of the 2014 Ebola outbreak on AFP surveillance in Guinea and Liberia. a retrospective cross-sectional analysis was performed for Guinea and Liberia to evaluate EVD´s impact on World Health Organization (WHO) AFP surveillance performance indicators during 2012-2015. both Guinea and Liberia met the WHO target non-polio AFP incidence rate nationally, and generally sub-nationally, prior to the EVD outbreak; rates decreased substantially during the outbreak in seven of eight regions in Guinea and 11 of 15 counties in Liberia. Throughout the study period, both Guinea and Liberia attained appropriate overall targets nationally for "notification" and "stool adequacy" indicators, but each country experienced periods of poor regional/county-specific indicator performance. these findings mirrored the negative effect of the Ebola outbreak on polio elimination activities in both countries and highlights the need to reinforce this surveillance system during times of crisis.

Experience and findings from surveillance peer review in Nigeria, August 2017-May 2019.

acute flaccid paralysis (AFP) surveillance is the gold standard of the Global Polio Eradication Initiative (GPEI) for detecting cases of poliomyelitis and tracking poliovirus transmission. Nigeria's AFP surveillance performance indicators are among the highest in countries of the World Health Organization (WHO) African Region. The primary AFP surveillance performance indicators are the rate of non-polio AFP among children and the proportion of timely, adequate specimen collection. The surveillance working group of the National Emergency Operations Centre assessed the quality of AFP surveillance data in some reportedly high-performing states. we conducted a retrospective review of AFP surveillance performance indicators in Nigeria for 2010-2019. We also reviewed data in reports from four groups of surveillance peer reviews and validation visits (conducted by in-country GPEI partners) during August 2017-May 2019 in 16 states with high primary AFP surveillance indicators; the validation visits reviewed clinical information and the dates of specimen collection and onset of paralysis with caretakers. there were consistently increasing AFP surveillance primary performance indicators during 2010-2016, followed by declines during 2017-2019. From the data for 16 states with peer reviews conducted from August 2017-May 2019, overall concordance of reported and "true" (validated) AFP indicator data in peer review investigations was highly variable. True AFP concordance ranged from 58%-100%, and stool timeliness concordance ranged from 56%-95%. The most common clinical causes of reported AFP cases that were not true AFP were spastic paralysis, malaria, sickle cell disease, and malnutrition. All the states that participated in peer reviews developed surveillance improvement plans based on the gaps identified. Nigeria has highly sensitive AFP surveillance according to reported primary AFP performance indicators. The findings of peer reviews indicate that the AFP surveillance system needs to be strengthened and well-supervised to enhance data quality.

Trends of key surveillance performance indicators of acute flaccid paralysis: a descriptive analysis, Uganda, 2015–2020

BackgroundPolio is disease caused by poliovirus which can in turn cause irreversible paralytic disease, presenting as Acute Flaccid Paralysis (AFP). A sensitive AFP surveillance system, in which all reported AFP cases are evaluated, first to determine if they are true AFP cases or not, is key for tracking polio eradication. True AFP cases are then later categorized as polio AFP or non-polio AFP (NPAFP) cases. Sensitivity is defined by meeting an annual NPAFP rate/100,000 population < 15 years of ≥ 4/100,000, and an annual stool adequacy (SA) rate of ≥ 80%. We describe Uganda’s AFP surveillance performance between 2015–2020, based on the WHO-recommended indicators, including; NPAFP and stool adequacy rate.MethodsWe performed a descriptive analysis of national AFP surveillance data, 2015–2020 obtained from ministry of health. We evaluated proportion of reported AFP cases that were true AFP, and changes in NPAFP and stool adequacy (SA) rate over the study period. We evaluated the trends in achieving the targeted NPAFP and SA rates from 2015–2020. We used QGIS to illustrate patterns in NPAFP and SA rates across districts and subregions.ResultsAmong 3,605 AFP cases reported and investigated countrywide from 2015–2020, 3,475 (96%) were true AFP cases. All the true AFP cases were non-polio related. District reporting was near-complete (97–100% each year). Overall, the mean NPAFP rate declined from 3.1/100,000 in 2015 to 2.1/100,000 in 2020. Less than 40% of districts met the NPAFP target rate in all years. The proportion of districts achieving the NPAFP target rate of ≥ 4/100,000 significantly declined from 35% in 2015 to 20% in 2020. The mean annual SA rate nationally was 88% from 2015–2020. Only 66% of districts achieved the SA target rate of ≥ 80% in the study period. The proportion of districts with SA rate ≥ 80% significantly increased from 68 to 80% between 2015 and 2020.ConclusionMost districts reported AFP cases. However, there was a decline in the NPAFP rate from 2015–2020 and few districts achieved the target rate. The suboptimal AFP surveillance system performance leaves the country at risk of missing ongoing poliovirus transmission. We recommend health worker training on active AFP searches, intensified supportive supervision, increase the number of environmental surveillance sentinel sites to boost AFP surveillance in the country, and periodic review meetings with districts to assess AFP surveillance performance.

Acute flaccid paralysis surveillance performance from 2011 to 2020 in Jonglei State, South Sudan: progress and challenges encountered.

IntroductionSouth Sudan reported the last indigenous wild poliovirus (WPV) in 2001 in Unity State, while the country was part of Sudan. In addition, the country reported an imported case of WPV in 2004-2005 and 2008-2009. The WPV circulation in the state was interrupted in 2009 and the last case was reported in Ayod county. The country continues to be at risk of importation of circulating vaccine-derived poliovirus type 2 (cVDPV2). In 2014 and 2020 the country experienced an outbreak of cVDPV2, in which Jonglei state was one of the affected states. Four out of 50 (8%) cVDPV2 cases in 2020 were reported from Jonglei State. The purpose of this study is to review surveillance performance indicators of Jonglei and compare them with the WHO surveillance performance standard and other country´s surveillance performances.Methodsretrospective secondary data analysis was conducted using the Jonglei state Acute Flaccid Paralysis (AFP) surveillance case-based database from 2011 to 2020. The reason for selecting Jonglei is because it is one of the poor performing states and is chronically hit by flood and internal conflicts. Data analyses were carried out using the Microsoft Excel (2016) program, where descriptive analysis frequencies, tables, and graphs were generated.Resultsthe study revealed that 346 AFP cases were reported in the counties of Jonglei state from 2011 through 2020. Out of 11 counties, 11 (100%) of them have reported suspected AFP cases. Children under five years accounted for 275 (79%) of all cases. The male gender accounted for 175 (51%) of all cases. A total of 249 (72%) had received three or more doses of Oral Polio Vaccine (OPV). Non-Polio Acute Flaccid Paralysis (NPAFP) rate varies from 1.2 in 2014 to 4.4 cases per 100,000 children under 15 years in 2018. The stool adequacy ranges from 58% in 2020 to 100% in 2011.Conclusionthe performance of Jonglei´s AFP surveillance system did not meet the WHO recommended target for both major AFP surveillance indicators (non-polio AFP rate and stool adequacy) during the study period.

Polio eradication in a chronic conflict setting lessons from the Republic of South Sudan, 2010-2020.

Introductionin 1988 the World Health Assembly set an ambitious target to eradicate Wild Polio Virus (WPV) by 2000, following the successful eradication of the smallpox virus in 1980. South Sudan and the entire African region were certified WPV free on August 25, 2020. South Sudan has maintained its WPV free status since 2010, and this paper reviewed the country’s progress, outlined lessons learned, and describes the remaining challenges in polio eradication.Methodssecondary data analysis was conducted using the Ministry of Health and WHO polio surveillance datasets, routine immunisation coverage, polio campaign data, and surveys from 2010 to 2020. Relevant technical documents and reports on polio immunisation and surveillance were also reviewed. Data analysis was conducted using EPI Info 7 software.Resultsadministrative routine immunisation coverage for bivalent Oral Polio Vaccine (OPV) 3rd dose declined from 77% in 2010 to 56% in 2020. In contrast, the administrative and post-campaign evaluation coverage recorded for the nationwide supplemental polio campaigns since 2011 was consistently above 85%; however, campaigns declined in number from four in 2011 to zero in 2020. Overall, 76% of notified cases of Acute Flaccid Paralysis (AFP) received three or more doses of the oral polio vaccine. The Annualized Non-AFP rate ranged between 4.0 to 5.4 per 100,000 under 15 years populations, and stool adequacy ranged from 83% to 94%.ConclusionSouth Sudan’s polio-free status documentation was accepted by the ARCC in 2020, thereby enabling the African Region to be certified WPV free on August 25, 2020. However, there are concerns as the country continues to report low routine immunisation coverage and a reduction in the number of polio campaigns conducted each year. It is recommended that the country conduct high-quality nationwide supplemental polio campaigns yearly to achieve and maintain the required herd immunity. It invests in its routine immunisation program while ensuring optimal AFP surveillance performance indicators.

Innovations in the Implementation of Polio Surveillance Enhancement Plan in Oyo State, Nigeria: Key Benefits, Lessons Learned, Challenges and Opportunities

Background: Nigeria attained the milestone of being certified wild poliovirus free in the year 2020. However, a drop in the key performance indicators of polio surveillance system was across various Local Government Areas (LGAs) in Oyo State. This drop highlighted the need for an innovative way of enhancing polio surveillance in Oyo State. Methods: This study was conducted in four phases and each phase utilized a cross-sectional study design and purposive sampling technique to select eligible LGAs and participants. LGAs that met at least two of the set-out criteria (had not reported at least a case of Acute Flaccid Paralysis (AFP) 12 months preceding the survey, with decline in AFP case detection rate, had not met AFP key indicators, are densely populated, and has an international border) were selected. A concurrent mixed method of data collection was utilized, and quantitative data were collected with a semi-structured questionnaire administered using Computer Assisted Personal Interviews (CAPI) during community active case search, health facility retroactive case search (HFRACS). Qualitative data collection was done through Focus Group Discussion (FGD). Surveillance intensification activities were conducted over eight weeks period. Data were analyzed using Microsoft Excel Software; summarization was done using frequencies and percentages while presentation was done using charts and spot maps. Results: A total of 1277, 49, 259 and 632 settlements, households and health facilities respectively were visited across 24 (73%) LGAs in Oyo State. Of the 150 suspected AFP cases identified, 45 (30%) were rejected cases, 33 (22%) were missed cases and 72 (48%) were true AFP cases. Non-Polio AFP Rate (NP-AFP rate) increased from 2.7 to 6.9 (P < 0.0001) after the surveillance intensification, also, the Non-Polio Enterovirus (NPENT) isolation was increased by 40% (16% to 23%). At the end of the intensification activities, all LGAs in Oyo State had met the WHO recommended Non-Polio Acute Flaccid Paralysis (NP-AFP) rate of ≥3/100,000 population. Conclusions: Innovative strategies implemented in AFP surveillance across Oyo State have resulted in improvement in AFP surveillance performance indicators in the State. There is therefore the need for dynamic and innovative ways of conducting AFP surveillance to prevent poliomyelitis epidemics and to ensure maintenance of Nigeria polio free certification status.

Evaluation of acute flaccid paralysis surveillance indicators in Sokoto state, Nigeria, 2012\u20132019: a secondary data analysis

BackgroundNigeria, the last endemic country in the WHO African Region, was certified free of Wild Polio Virus (WPV) in 2020. However, due to low immunity in some communities in Sokoto, outbreaks of the circulating Vaccine Derived Polio Virus (cVDPV) occur. The aim of this study is to evaluate the Acute Flaccid Paralysis (AFP) surveillance indicators in Sokoto state, Nigeria.MethodsThis retrospective study was an analysis of routinely collected AFP surveillance data between 2012 and 2019 by the Sokoto state surveillance network. We assessed the Sokoto state AFP surveillance system using the AFP surveillance performance indicators. We performed all analyses using Microsoft Excel 2019.ResultsCumulatively, 3001 Acute Flaccid Paralysis (AFP) cases were reported over the evaluation period, out of which 1692 (56.4%) were males, and 2478 (82.4%) were below five years. More than half, 1773 (59.1%), had a fever at the beginning of the disease, and 1911 (63.7%) had asymmetric paralysis. The non-polio AFP rate (9.1 to 23.5% per 100,000 children < 15 years old) and stool adequacy rate (92.5 to 100%) indicate high sensitivity. The proportion of cases that had stool samples collected early, timely transported to the laboratory and arrived at the laboratory in optimal condition were all above the World Health Organization (WHO) minimum standard of 80%. There was inadequate profile documentation of some suspected cases.ConclusionsSokoto State has exceeded the WHO minimum standards in most of the AFP surveillance indicators. The performance of the system is sufficient enough to detect any reintroduction of WPV into the state. However, there is a need for improvement in data quality.

Impact of the Protracted War in Yemen on the Acute Flaccid Paralysis Surveillance System: Retrospective Descriptive Analysis.

BackgroundHighly sensitive acute flaccid paralysis (AFP) surveillance, which includes immediate case investigation and specimen collection, is critical for achieving global polio eradication. In Yemen, the Acute Flaccid Paralysis Surveillance System (AFPSS) was launched in 1998 to achieve the polio eradication target. Although Yemen was certified as a polio-free country in 2009, the protracted war since 2015 has placed the country at risk for polio reemergence.ObjectiveThe objectives of this analysis were to evaluate the performance of the Yemen AFPSS at both the national and governorate levels, and to assess the impact of the ongoing war on the performance.MethodsRetrospective descriptive analysis was performed on Yemen secondary AFP surveillance data for the years 2014 (before the war) and 2015-2017 (during the war). Data comprising all children <15 years old reported as having AFP were included in the analysis. AFP surveillance performance was evaluated using World Health Organization–specified AFP surveillance indicators.ResultsAt the national level, all indicators were met before and after the war except for “lab results received within ≤28 days,” which was unmet since the war erupted. Furthermore, the indicator “stool specimens arriving at a central level within ≤3 days” was unmet after the war but only in 2017. At the governorate level, although the indicators “adequacy” and “stool specimens arriving at the laboratory in good condition” were met before the war in all governorates, the former indicator was unmet in 9 (41%) governorates since the war erupted and the latter indicator was also unmet in 9 governorates (41%) but only in 2017.ConclusionsThe findings show that some AFP surveillance indicators were negatively impacted by eruption of the war in Yemen due to closure of the Sana’a capital airport and postponement of sample shipment to the reference laboratory, which remained under long-term poor storage conditions. To ensure rapid detection of polio cases, improving specimen collection, storage, and transportation, together with proper and timely shipment of specimens to the reference laboratory should be considered.

Surveillance to Track Progress Toward Polio Eradication - Worldwide, 2019-2020.

When the Global Polio Eradication Initiative (GPEI) was established in 1988, an estimated 350,000 poliomyelitis cases were reported worldwide. In 2020, 140 wild poliovirus (WPV) cases were confirmed, representing a 99.99% reduction since 1988. WPV type 1 transmission remains endemic in only two countries (Pakistan and Afghanistan), but outbreaks of circulating vaccine-derived poliovirus (cVDPV) occurred in 33 countries during 2019-2020 (1,2). Poliovirus transmission is detected primarily through syndromic surveillance for acute flaccid paralysis (AFP) among children aged <15 years, with confirmation by laboratory testing of stool specimens. Environmental surveillance supplements AFP surveillance and plays an increasingly important role in detecting poliovirus transmission. Within 2 weeks of COVID-19 being declared a global pandemic (3), GPEI recommended continuing surveillance activities with caution and paused all polio supplementary immunization activities (4). This report summarizes surveillance performance indicators for 2019 and 2020 in 42 priority countries at high risk for poliovirus transmission and updates previous reports (5). In 2020, 48% of priority countries* in the African Region, 90% in the Eastern Mediterranean Region, and 40% in other regions met AFP surveillance performance indicators nationally. The number of priority countries rose from 40 in 2019 to 42 in 2020.† Analysis of 2019-2020 AFP surveillance data from 42 countries at high risk for poliovirus transmission indicates that national and subnational nonpolio AFP rates and stool specimen adequacy declined in many priority countries, particularly in the African Region, suggesting a decline in surveillance sensitivity and quality. The findings in this report can be used to guide improvements to restore a sensitive surveillance system that can track poliovirus transmission and provide evidence of interruption of transmission.

New analytic approaches for analyzing and presenting polio surveillance data to supplement standard performance indicators

BackgroundSensitive surveillance for acute flaccid paralysis (AFP) allows for rapid detection of polio outbreaks and provides essential evidence to support certification of the eradication of polio. However, accurately assessing the sensitivity of surveillance systems can be difficult due to limitations in the reliability of available performance indicators, including the rate of detection of non-polio AFP and the proportion of adequate stool sample collection. Recent field reviews have found evidence of surveillance gaps despite indicators meeting expected targets. MethodsWe propose two simple new approaches for AFP surveillance performance indicator analysis to supplement standard indicator analysis approaches commonly used by the Global Polio Eradication Initiative (GPEI): (1) using alternative groupings of low population districts in the country (spatial binning) and (2) flagging unusual patterns in surveillance data (surveillance flags analysis). Using GPEI data, we systematically compare AFP surveillance performance using standard indicator analysis and these new approaches. ResultsApplying spatial binning highlights areas meeting surveillance indicator targets that do not when analyzing performance of low population districts. Applying the surveillance flags we find several countries with unusual data patterns, in particular age groups which are not well-covered by the surveillance system, and countries with implausible rates of adequate stool specimen collection. ConclusionsAnalyzing alternate groupings of administrative units is a simple method to find areas where traditional AFP surveillance indicator targets are not reliably met. For areas where AFP surveillance indicator targets are met, systematic assessment of unusual patterns (‘flags’) can be a useful prompt for further investigation and field review.

Assessment of acute flaccid paralysis surveillance performance in East and Southern African countries 2012 - 2019.

Introduction:polio eradication initiatives started in 1988, this is almost the past 32 years following the WHA resolution 41.8 of eradicating polio by the year 2000. As of 2019, only 3 countries remained to be polio endemic globally, Afghanistan, Pakistan and Nigeria. The east and southern sub-region countries had shown progressive achievement towards polio eradication and to start with the African regional certification. The availability of sensitive AFP surveillance performance is among important strategies in the achievement of polio eradication. We, therefore, decided to conduct this assessment of AFP performance from 2012 to 2019 in the ESA sub-region have evidence documentation and support the certification process of the WHO AFRO region.Methods:we reviewed all reported acute flaccid paralysis (AFP) cases from 19 countries in the ESA sub region with the date of onset of paralysis from 1 January 2012 to 31 December 2019. The data were run to descriptive analysis based on the personal characteristics and AFP surveillance performance indicators parameters.Results:a total of 46,014 AFP cases were reported from 19 countries in the ESA countries who were paralyzed from 1 January 2012 to 31 December 2019. The most affected age group was children aged 0 to 3 years old where 19,740 children with acute paralysis were reported representing 42.9% of the total reported AFP for the period. The overall assessment of the non-polio AFP rate, there is an increase from a rate of 2.7 in 2012 to 3.5 in 2019 per 100,000 population aged less than 15 years, reflects a significant change with a p-value of 0.040 (95% C.I. ranges from 0.035 to 1.564). Furthermore, the percentage of stool adequacy raised from 86.4% in 2012 to 88.5% in 2019, with an observed 2.1% difference and no significant change over the 8 years.Conclusion:we observed an overall increase in the sensitivity of the AFP surveillance performance for the ESA sub-region countries from 2012 to 2019 using the national performance indicators. The COVID-19 pandemic paused an operational challenge for AFP surveillance performances from 2020. A further subnational surveillance performance analysis is suggested.

Profile of polio-compatible cases in Nigeria, 2006\u20132016

BackgroundThe tremendous progress made by Nigeria towards polio eradication has recently suffered a setback with the isolation of circulating vaccine-derived poliovirus (cVDPV) type 2 from environmental samples and confirmation of four wild poliovirus (WPV) cases from acute flaccid paralysis (AFP) cases, with dates of onset of paralysis in July and August 2016. All these viruses were confirmed from the security-challenged northeastern state of Borno. Polio-compatible cases exist in Nigeria, and they indicate surveillance failure. Surveillance, therefore, has to be strengthened for the country to achieve certification. The objective of this paper is to highlight the epidemiological profile and magnitude of polio-compatible cases in Nigeria during the reporting period, as well as immunization and surveillance response activities conducted to close immunity and surveillance gaps.MethodsWe conducted a retrospective review of AFP surveillance performance and polio-compatible cases in Nigeria between 2006 and 2016 from the AFP database at the World Health Organization Country Office. We also reviewed and compared key epidemiological features of polio-compatible cases with those of wild poliovirus cases during the reporting period.ResultsThe non-polio AFP rate improved from 6.5 in 2006 to 19.5 in 2016. The corresponding figures for stool adequacy rates were 88 and 98%. The total number of polio-compatible cases reported during the reporting period was 888, with the highest number (194) of cases reported in 2006 and the least (24) in 2016. Clusters of polio-compatible cases were reported every year during the reporting period except in 2015. The highest number (65) of polio-compatible cases in clusters was reported in 2006. The key epidemiological features of polio-compatible and wild poliovirus cases were similar.ConclusionAFP surveillance performance has improved significantly during the reporting period. Surveillance gaps still existed as shown by the presence of orphan viruses and polio-compatible cases, and these gaps need to be identified and closed to achieve certification.

Acute flaccid paralysis (AFP) surveillance intensification for polio certification in Kaduna state, Nigeria: lessons learnt, 2015\u20132016

BackgroundNigeria has made remarkable progress in its current efforts to interrupt wild poliovirus transmission despite the re-emergence of wild poliovirus in 2016. The gains made in Nigeria have been achieved through concerted efforts by governments at all levels, traditional leaders, health workers, caregivers, and development partners. The efforts have involved an elaborate plan, coordination, and effective implementation of routine immunization services, supplemental immunization activities, and acute flaccid paralysis (AFP) surveillance.MethodsWe conducted the following activities to strengthen AFP surveillance in Kaduna state: a monetary reward for all AFP cases reported by health workers or community informants and verified as “true” AFP by a World Health Organization (WHO) cluster coordinator; training and sensitization of surveillance officers, clinicians, and community informants; recruitment of more personnel and expansion of the surveillance network; and the involvement of special populations (nomadic, hard-to-reach, and border communities) and caregivers in stool sample collection. The paired t test was used to evaluate the impact of the different initiatives implemented in Kaduna state to intensify AFP surveillance in 2016.ResultsThere was increased annualized non-polio AFP rate (ANPAFPR) in 21 out of 23 Local Government Areas (LGAs) of Kaduna state 6 months after implementation of different initiatives to intensify AFP surveillance. The AFP reported by the special population increased in 15 out of 23 LGAs. Statistical analyses of mean scores of ANPAFPR before and after the interventions using the paired t test revealed a significant difference in mean scores: mean = 19.7 (standard deviation (SD) = 16.1) per 100,000 < 15 years old in July–December 2015, compared with 38.0 (SD = 21.6) per 100,000 < 15 years old in January–June 2016 (p < 0.05). Likewise, analysis of silent wards using the paired t test showed a significant difference in mean scores: mean = 4.0 (SD = 2.1) in July–December 2015 compared with 2.4 (SD = 1.8) in January–June 2016 (p < 0.05).ConclusionThe different initiatives implemented in 23 LGAs of Kaduna state to intensify AFP surveillance may be responsible for the significant improvement in the AFP surveillance performance indicators in 2016.

Acute flaccid paralysis surveillance, Kano State, Nigeria: 2009 - 2015

Introduction: the gold standard for detecting Poliomyelitis cases is by acute flaccid paralysis (AFP) surveillance. In August and October, 2016 Wild polio virus (WPV) type 1 and cVDPV2 were detected in Northern Nigeria. Hence there is need to close any gaps in the surveillance process. This study describes the epidemiology and trend of AFP/WPV, it also evaluates the AFP surveillance performance indicators in Kano State. Methods: secondary data analysis of Kano State AFP surveillance data from January 2009 to December 2015 was carried out. Data were obtained from Kano State Ministry of Health-WHO database. Ethical clearance was obtained from Kano State Ministry of Health. Data was analyzed using Epi-info version 7.2.0.1. Results: overall, 4644 AFP cases were reported over the study period. After stool analysis, 1058 cases were confirmed to be true AFP cases. Fifty six percent of the AFP cases were males and 83% were less than five years of age. Most (69%) of the cases received <3 doses of Oral polio vaccine (OPV), while 30% were zero dose. There was reduction in the number of AFP cases across the years from 321 cases in 2009 to 0 in 2015. WPV cases were 145 or 14%. There was increase in the prevalence of WPV in March, May and July throughout the study period. More cases (%) were reported from Ungogo local government area. Evaluation of the performance indicators showed that the AFP surveillance system was not timely, complete and Core IDSR indicators were unmet over the study period. Conclusion: AFP/WPV was prevalent among male children less than 5 years, who had received < 3 doses of OPV. Kano State AFP surveillance system did not meet the target for some of its performance indicators. We recommended improvement on OPV immunization and the AFP surveillance system in the state.

Adequacy of Acute Flaccid Paralysis (AFP) Surveillance Indicators for Iran in 2016

Eradication of polio as a largest public health innovation is led by the World Health Organization (WHO) in the world (1). The main strategies to reach this goal included improved routine immunization, adequate response to outbreaks and effective surveillance (2). Acute Flaccid Paralysis (AFP) surveillance has considered as a comprehensive program for polio eradication, by identification of areas of poliovirus transmission as well as cases of importation. Polio-free certification should be confirmed through surveillance (3). AFP surveillance has some indicators, where used to determine sufficient sensitivity of surveillance to detect poliovirus transmission in communities (4). Table.1 shows two cores of AFP surveillance performance indicators including non-polio AFP and stool adequacy rates for Iran in 2016 (5). In the year of 2016 recorded the 776 AFP cases (Non polio AFP rate: 4.2 per 100,000

'Silent' and 'noisy' areas: acute flaccid paralysis surveillance at subnational level, Australia, 2001-2015.

Acute flaccid paralysis (AFP) surveillance rates are used as an indicator of surveillance sensitivity to detect poliomyelitis with an expected rate of ≥1 case per 100 000 population in children under 15 years of age. The Australian AFP detection rates at sub-national (statistical local area) level were analysed using χ2 goodness of fit tests and exact Poisson probabilities for the combined years 2001-2015 to detect 'silent areas', which may require improved AFP detection efforts, and areas with greater than expected rates, which may indicate unexplained clusters such as those due to enterovirus infection. Eight (n=8/87, 9%) local areas had AFP surveillance detection rates that were less than expected, and eighteen local areas (n=18/87, 21%) had rates that were greater than expected. However, based on available evidence, it is unlikely that these indicated previously unidentified, enterovirus clusters. While Australia has regularly met the national AFP surveillance performance indicators, at the subnational level nine per cent of local areas demonstrated statistically significant lower AFP detection rates. All countries, even those with relatively small populations, should actively identify silent AFP areas to prompt surveillance improvements.

Sensitivity of Acute Flaccid Paralysis Surveillance in Nigeria (2006-2015)

Background: Nigeria has made tremendous progress towards polio eradication. The country was removed from the list of polio endemic countries by the World Health Organization (WHO) in September 2015. The last cases of wild poliovirus (WPV) and circulating vaccine derived poliovirus (cVDPV) from acute flaccid paralysis (AFP) cases had onset of paralysis in July 2014 and May 2015 respectively. The country has completed the phase I of laboratory containment of poliovirus activities, has achieved and maintained certification standard surveillance and is now in the process of ensuring adequate documentation preparatory to certification in 2017. Methods: We conducted a retrospective review of AFP surveillance performance in Nigeria between 2006 and 2015 from the AFP database at the WHO Country Office. We also reviewed rapid surveillance assessment reports conducted in various states of the country within the reporting period to identify surveillance strengths and gaps as well as recommendations put forward to improve polio surveillance performance. Results: The sensitivity of AFP surveillance in Nigeria increased consistently over the past 10 years. The number of confirmed and polio compatible cases has reduced significantly during the reporting period. AFP reporting sites have been prioritized for active surveillance and community informants have been engaged and cut across several key stakeholders in community health care delivery system. Conclusion: The AFP surveillance performance in Nigeria during the reporting period demonstrated high level of sensitivity that can be relied upon to timely detect polio outbreak. Residual surveillance gaps at sub national levels however exist and must be closed to be able to identify remaining areas of poliovirus transmission should such exist as well as promptly detect possible cases of importation. Quality surveillance is also required for certification.

Improved acute flaccid paralysis surveillance performance in the Democratic Republic of the Congo, 2010-2012.

The Democratic Republic of the Congo (DRC) began polio eradication activities in 1996. By 2001, DRC was no longer polio endemic. However, wild poliovirus (WPV) transmission was reestablished in 2006 continuing through 2011 (last WPV case onset 20 December 2011), and vaccine-derived poliovirus type 2 (VDPV2) outbreaks occurred during 2004-2012 (last VDPV2 case onset 4 April 2012). Gaps in acute flaccid paralysis (AFP) surveillance have been consistently documented. AFP surveillance indicators were assessed at the national, provincial, and zone de santé (ZS) levels for 2010-2012. A spatiotemporal analysis of compatible, WPV type 1 (WPV1), and VDPV2 cases was performed. During 2010-2012, AFP cases were reported from all provinces but not every ZS, particularly in Equateur province and Province Orientale. A spatiotemporal relationship between compatible, WPV1, and VDPV2 cases was noted. Nonpolio AFP rates met objectives at national and provincial levels but were sub-optimal in certain ZS. National and provincial trends in timely stool collection, stool condition, adequate stool, and 60-day follow-up exams improved. DRC's AFP surveillance system is functional and improved during 2010-2012. Maintaining improvements and strengthening AFP case detection at the ZS level will provide further support for the apparent interruption of WPV and VDPV2 transmission.