Acute Flaccid Paralysis Surveillance Research Articles

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.

The impact of surveillance and other factors on detection of emergent and circulating vaccine derived polioviruses.

Background: Circulating vaccine derived poliovirus (cVDPV) outbreaks remain a threat to polio eradication. To reduce cases of polio from cVDPV of serotype 2, the serotype 2 component of the vaccine has been removed from the global vaccine supply, but outbreaks of cVDPV2 have continued. The objective of this work is to understand the factors associated with later detection in order to improve detection of these unwanted events. Methods: The number of nucleotide differences between each cVDPV outbreak and the oral polio vaccine (OPV) strain was used to approximate the time from emergence to detection. Only independent emergences were included in the analysis. Variables such as serotype, surveillance quality, and World Health Organization (WHO) region were tested in a negative binomial regression model to ascertain whether these variables were associated with higher nucleotide differences upon detection. Results: In total, 74 outbreaks were analysed from 24 countries between 2004 and 2019. For serotype 1 (n=10), the median time from seeding until outbreak detection was 284 (95% uncertainty interval (UI) 284-2008) days, for serotype 2 (n=59), 276 (95% UI 172-765) days, and for serotype 3 (n=5), 472 (95% UI 392-603) days. Significant improvement in the time to detection was found with increasing surveillance of non-polio acute flaccid paralysis (AFP) and adequate stool collection. Conclusions: cVDPVs remain a risk globally; all WHO regions have reported at least one VDPV outbreak since the first outbreak in 2001. Maintaining surveillance for poliomyelitis after local elimination is essential to quickly respond to both emergence of VDPVs and potential importations. Considerable variation in the time between emergence and detection of VDPVs were apparent, and other than surveillance quality and inclusion of environmental surveillance,the reasons for this remain unclear.

Modeling Poliovirus Surveillance and Immunization Campaign Quality Monitoring Costs for Pakistan and Afghanistan for 2019-2023.

The Global Polio Eradication Initiative (GPEI) Strategic Plan for 2019-2023 includes commitments to monitor the quality of immunization campaigns using lot quality assurance sampling surveys (LQAS) and to support poliovirus surveillance in Pakistan and Afghanistan. We analyzed LQAS and poliovirus surveillance data between 2016 and 2020, which included both acute flaccid paralysis (AFP) case-based detection and the continued expansion of environmental surveillance (ES). Using updated estimates for unit costs, we explore the costs of different options for future poliovirus monitoring and surveillance for Pakistan and Afghanistan. The relative value of the information provided by campaign quality monitoring and surveillance remains uncertain and depends on the design, implementation, and performance of the systems. Prospective immunization campaign quality monitoring (through LQAS) and poliovirus surveillance will require tens of millions of dollars each year for the foreseeable future for Pakistan and Afghanistan. LQAS campaign monitoring as currently implemented in Pakistan and Afghanistan provides limited and potentially misleading information about immunization quality. AFP surveillance in Pakistan and Afghanistan provides the most reliable evidence of transmission, whereas ES provides valuable supplementary information about the extent of transmission in the catchment areas represented at the time of sample collection.

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.

A Year of Surveillance of Acute Flaccid Paralysis in the Children Welfare Teaching Hospital

A Year of Surveillance of Acute Flaccid Paralysis in the Children Welfare Teaching Hospital

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.

Surveillance Review System to Track Progress Towards Polio Eradication in the Horn of Africa.

BackgroundThe risk for importation and reintroduction wild poliovirus in areas that have been cleared of the wild poliovirus in the Horn of Africa will remain if the surveillance systems are weak and porous.MethodsConsequently, the Horn of Africa Polio Coordinating Office in Nairobi, together with partners conducted surveillance reviews for some of the countries in the Horn of Africa, especially Ethiopia, Kenya and Somalia to identify gaps in the polio surveillance and provided recommendations for improved surveillance. Structured questionnaires collected information about acute flaccid paralysis (AFP) surveillance resources, training, data monitoring, and supervision at provincial, district, and health facility levels. Other information collected included resource availability, management and monitoring of AFP surveillance.ResultsThe result revealed that although AFP surveillance systems were well established in these countries, a number of gaps and constraints existed. Widespread deficiencies and inefficient resource flow systems were observed and reported at all levels. There were also deficiencies related to provider knowledge, funding, training, and supervision, and were particularly evident at the health facility level. These weaknesses were corroborated with the sustained transmission of polioviruses in the region, where the surveillance systems were not sensitive enough to pick the viruses.ConclusionThe review teams made useful recommendations that led to strengthening of the surveillance systems in these countries, including the formation and use of village polio volunteers in the south and central zones of Somalia, where security was heavily compromised and surveillance officers lacked regular access to the communities.

Non-Polio Enteroviruses from Acute Flaccid Paralysis Surveillance in Korea, 2012–2019

The risk of polio importation and re-emergence persists since epidemic polio still occurs in some countries, and the resurgence of polio occurring almost 20 years after polio eradication was declared in Asia has been reported. We analyzed the results of acute flaccid paralysis (AFP) surveillance in Korea to assess the quality of AFP surveillance and understand the etiology of non-polio enterovirus (NPEV)-associated central nervous system diseases in a polio-free area. We investigated 637 AFP patients under 15 years of age whose cases were confirmed during 2012–2019 by virus isolation, real-time reverse transcription polymerase chain reaction, and VP1 gene sequencing. Among the 637 AFP cases, NPEV was detected in 213 (33.4%) patients, with the majority observed in EV-A71, with 54.9% of NPEV positives. EV-A71 has been shown to play a role as a major causative agent in most neurological diseases except for Guillain-Barré syndrome (GBS), acute disseminated encephalomyelitis (ADEM), and meningitis. This study provides information on the AFP surveillance situation in Korea and highlights the polio eradication stage in the monitoring and characterization of NPEV against the outbreak of neurological infectious diseases such as polio.

Detection of non-polio and polio enteroviruses in Acute Flaccid Paralysis surveillance in Turkey.

Poliomyelitis was a disease feared worldwide, striking suddenly and paralysing mainly children for life. Monitoring of suspected cases of poliomyelitis is carried out with Acute Flaccid Paralysis (AFP) surveillance in Turkey. This study examines national data of AFP surveillance and the epidemiology of enteroviruses (EV) in Turkey from 2000 to 2019 and gives an overview of the detected serotypes of EVs. A total of 13,640 samples collected from patients with 5216 AFP pre-diagnosed cases (2 samples from each patient) and 3,208 contacts, during a 20-year period (2000-2019) were investigated. All isolated polioviruses were tested for their wild or vaccine origin according to the WHO recommended protocol by PCR and sequencing analysis were performed. Enterovirus positivity was detected in a total of 915 cases, which were identified as 204 Sabin-like polio virus (SLPV) and 711 non-polio enterovirus (NPEV). Of the 204 SLPV, 141 (69.1%) AFP were detected in patients and 63 (30.9%) were detected in samples taken from their contacts. Of the 711 NPEVs, 516 (72.5%) were from AFP cases and 195 (27.5%) were detected in samples taken from their contacts. It is concluded that the reason for the higher detection rate of NPEV in samples from AFP pre-diagnosed cases is attributed to the polio vaccination rates reaching 97% between 2008 and 2019 in Turkey. The most frequently detected NPEV serotypes were Coxackie A24, B3, and Echo 30. This retrospective study is the first comprehensive study in Turkey to evaluate the results of the AFP surveillance in the last 20 years.

Evaluation of the Acute Flaccid Paralysis Surveillance System of Polio Free in East Java, Indonesia, 2019

Background: Proving that the wild polio virus no longer exists in Indonesia, the symptoms must be found thatresemble polio. These symptoms are found in patients with AFP (Acute Flaccid Paralysis). AFP surveillanceis an observation made of all cases of acute paralysis or AFP in children aged &lt;15 years who are vulnerableto polio. The priority problem that is still found in the East Java Provincial Health Office regarding AFPsurveillance is the reduction in the discovery of non-polio AFP cases and adequate specimens.Aims: The purpose of this study was to analyze the implementation of AFP surveillance activities in the EastJava Province Health Office in 2019.Methods: Data collection was carried out by primary and secondary to study the AFP surveillance overview.Primary data were obtained from in depth interviews with AFP surveillance program holders in East JavaProvincial Health Office. Secondary data is processed using Microsoft Office Excel, Epi Info and QuantumGIS.Results: The result is in 2019 the rate of non-polio AFP and the percentage of adequate specimens in EastJava Province has under the target. In 2019 there was a decrease compared to the previous year, the nonpolio AFP rate was 1.64 and the percentage of adequate specimens was 56.2%. Only as many as six districts/ cities in East Java Province had pass these two indicators.Conclusion: The lack of visits and reports from both the hospital and the community is one of causativefactor. Intensive and routine AFP surveillance is needed to monitor the emergence of polio cases

AFP Case Detection Along International Border Communities in Oyo State: Challenges, Opportunities and Threats

A weak AFP surveillance system constitutes a major threat to Nigeria’s polio free certification status. This study investigates the factors that have affected AFP surveillance, case detection along the international border settlements of Oyo state, Nigeria. A cross-sectional survey was conducted between 26^th-31^th December 2018 using structured questionnaires uploaded onto Open Data Kit-collect (ODK) mobile software in 4 LGAs in Oyo state. Overall, 427 respondents (community members=420, community informants=7) participated in this study. On the average, 10% and 46% of the community members and informants could identify the various aspects of the AFP case definition. Majority of the community members weren’t aware of AFP surveillance neither were they aware of their AFP focal person/DSNO or where to report AFP cases. Barriers to case reporting include, irregular movements of commercial vehicles, swampy roads during rainy seasons, rocky roads during dry seasons; poor communication networks; and poor modes of transportation. The accessibility and difficulty of terrain along these international boarders has greatly hindered surveillance activities in their corresponding communities. If steps are taken to improve accessibility in such areas, we believe that AFP case detection and reporting would also improve.

ACUTE FLACCID PARALYSIS REGISTERED FOR THE PERIOD 2012-2020, IN STARA ZAGORA REGION

Acute Flaccid Paralysis (AFP) is a clinical syndrome. There are many infectious and non-infectious causes of AFP. Poliomyelitis caused by the wild polio virus (the natural circulating strain of polio) is one of the causes of AFP. As a part of the worldwide campaign to eradicate polio, all countries do surveillance for polio by looking for clinical cases of AFP. The purpose of the study is to describe the cases of Acute Flaccid Paralysis, without Paresis Nervi facialis, in the Stara Zagora region for the period 2012-2020. Methods: A retrospective, descriptive analysis was performed on the parameters: diagnosis, seasonality, sex, residence, age, clinical data, and comorbidities, results of follow-up examinations, polio vaccine administration, and timeliness of studies. Results: There were 9 cases of AFP, without Paresis nervi facialis, registered and reported for the Stara Zagora region, for the period 2012 – 2020. The children in 3 years old were more affected- 4 patients. About the coverage with polio vaccine: 7 of the patients had 4 doses, 1- had 6 doses, 1 child had 5 doses, and + 1 zero dose. 100% of children are covered, according to their age, with IPV. Follow-up in 6 of the patients is without residual paresis and complications. Residual paresis was found in 1 of the cases. In 2 patients no control examination was performed due to migration. Conclusion: The correct epidemiological diagnosis is the way to timely and corrects clinical diagnosis. AFP Surveillance is of particular importance as well as fecal sampling up to 48 hours, from the onset of paralysis, and follow-up after the 60th day in children &lt;15 years.

Acute flaccid paralysis and enterovirus in Spain. Results from 2019 surveillance

ObjectiveThe Acute Flaccid Paralysis (AFP) and Enterovirus (EV) Surveillance systems are key to achieving the eradication of poliomyelitis worldwide. Among others, they allow detecting the reintroduction of poliovirus (PV) from endemic areas. Material and methodsAnalysis of the results of the protocol for the surveillance of AFPs and EVs in 2019 and the standard quality index established by the World Health Organization. Results38 cases of AFP were reported, -notification rate of 0.55 / 100,000 < 15 years- and adequate collection of clinical samples was achieved in 50% of the cases. The quality of AFP surveillance is summarized in the Surveillance Index, which in 2019 was 0.28 away from the 0.80 established as the standard by WHO. EV were detected in 11.7% of AFPs and in 5.5% of other syndromes (meningitis, mucocutaneous and respiratory), the predominant types were E-7, E-30, E-11, CV-A6 and E -13. A case of VDPV without polio clinical presentation in an immunosupressed adult was detected. ConlusionsAs long as there is circulation of poliovirus in the world, it is necessary to keep the surveillance systems of EV -polio and nonpolio- active, reinforcing the collection and processing of samples to detect the unexpected circulation of these viruses in time.

Epidemiology of Guillain-Barré Syndrome in Iranian Children Aged 0-15 Years (2008-2013).

Objective Guillain-Barré Syndrome (GBS) is an acute inflammatory polyneuropathy characterized by a rapid progressive symmetric weakness. The GBS is the most common cause of acute flaccid paralysis (AFP) in most parts of the world. This study was carried out to investigate the epidemiological features of GBS in Iranian children. Materials & Methods The data were extracted using the AFP surveillance system that is a national screening program to detect all cases of AFP aged 0-15 years around the country. National Population Statistics data and AFP demographic data during 2008-2013 intervals were obtained from the relevant authorities in the Ministry of Health in Iran. The GBS cases were then extracted from the aforementioned database. The Chi-square test and Fisher’s exact test were used for statistical analysis.ResultsA total of 1884 cases of GBS were identified in the study period, and the average annual incidence rate was 1.72 per 100,000 individuals. The highest incidence rate was within the range of 0-5 years. There was no statistically significant relationship between the incidence of GBS and the season in the whole country.Conclusion High costs of GBS treatment, morbidity and occasional mortality, and number of new cases, which is estimated to be approximately 300 individuals per year, need the particular attention of the health system.

Parálisis flácida aguda y enterovirus en España. Resultados de la vigilancia en 2019

ObjectiveThe Acute Flaccid Paralysis (AFP) and Enterovirus (EV) Surveillance systems are key to achieving the eradication of poliomyelitis worldwide. Among others, they allow detecting the reintroduction of poliovirus (PV) from endemic areas. Material and methodsAnalysis of the results of the protocol for the surveillance of AFPs and EVs in 2019 and the standard quality index established by the World Health Organization (WHO). Results38 cases of AFP were reported —notification rate of 0.55/100,000<15 years— and adequate collection of clinical samples was achieved in 50% of the cases. The quality of AFP surveillance is summarized in the Surveillance index, which in 2019 was 0.28 away from the 0.80 established as the standard by WHO. EV were detected in 11.7% of AFPs and in 5.5% of other syndromes (meningitis, mucocutaneous and respiratory), the predominant types were E-7, E-30, E-11, CV-A6 and E -13. A case of VDPV without polio clinical presentation in an immunosupressed adult was detected. ConlusionsAs long as there is circulation of poliovirus in the world, it is necessary to keep the surveillance systems of EV —polio and nonpolio— active, reinforcing the collection and processing of samples to detect the unexpected circulation of these viruses in time.

Description of non-polio enteroviruses identified in two national surveillance programmes in South Africa.

BackgroundHuman enteroviruses (EV) consist of 106 serotypes and four species: EV-A, EV-B, EV-C and EV-D. Enteroviruses cause clinical symptoms varying from severe to mild. Knowledge of EV burden in South Africa is limited, and as non-polio EV are important causes of acute flaccid paralysis (AFP) and meningitis, information on the circulating serotypes is vital.MethodsBetween 2010 and 2012, a total of 832 stool and viral isolate specimens were obtained from two national surveillance programmes at the National Institute for Communicable Diseases: the Rotavirus Sentinel Surveillance Programme (RSSP) and the AFP surveillance programme. Real-time polymerase chain reaction and Sanger sequencing were performed to detect and serotype EV.ResultsNon-polio EV were detected in 446 specimens, of which 308 were sequenced. Stool specimens yielded a greater variety of serotypes than viral cultures. EV-B viruses were predominant (58.44%), whilst EV-C viruses were detected in 31% of the specimens tested. South African prevalence for these viruses was higher than other countries, such as France with less than 2%, and Spain and the United States with less than 10%. The most common serotype detected was Enterovirus 99 (EV-C, 8.63%), which has not been reported in other regions.ConclusionDirect sequencing from stool specimens yields a broader, more comprehensive description of EV infections compared to sequencing from viral cultures. Disease-associated serotypes were detected, but only in small numbers. This study provides a baseline for EV strain circulation; however, surveillance needs to be expanded to improve EV knowledge in South Africa.

Acute flaccid paralysis surveillance system evaluation-Enugu state, Nigeria 2015–2018

Background: Nigeria is one of the three polio-endemic countries worldwide. Wild polio virus was reported last in Nigeria by August 2016 although pockets of circulating vaccine derived viruses’ infection and vaccine associated paralytic polio still occur. As part of the polio endgame strategy Nigeria targets to achieve and sustain optimum surveillance performance indicators in all States by December 2018. We evaluated the acute flaccid paralysis (AFP) surveillance system in Enugu State to assess if the target for these indicators are being met. Methods and materials: We used an adapted US CDC Updated Guidelines for Evaluating Public Health Surveillance Systems. We reviewed of AFP surveillance data collected 2015–2018. We conducted key informant interviews and focus group discussion with purposively selected stakeholders. We collected data from 30 randomly selected AFP Surveillance officers in the state using an adapted questionnaire and recorded frequencies and proportions of key indicators. Results: One compatible poliovirus case was identified in 2015 among the 1211 AFP cases recorded. The case definition of AFP and tools for reporting are simple. The system is mainly funded by foreign partners although the main challenge is sustainability. The system is unstable as there are few trained staff who are regularly assigned other duties or transferred to other departments other than AFP surveillance. The system is flexible, and accepted by all stakeholders. The sensitivity of the system measured by the annualized Non-Polio AFP (NPAFP) rate is 15.1 ± 2.7 (target of ≥2/100,000 population). The mean data quality was 94%, SD: 2.8 (target ≥90). Mean stool adequacy and timeliness of reporting were 83.9 ± 14.3% and 91.0 ± 8.6% respectively both having target of ≥80%. Case investigations done in ≤48 h: Mean 89 ± 7.4, non-polio enterovirus isolation rate: Mean 39.5 ± 19.4, target >10% and 60 days follow up Mean 85.2 SD (17.0). Conclusion: Enugu State AFP surveillance is meeting most of its target although stability of the system is suboptimal. We recommended that Enugu state government train a pool of health officers on AFP surveillance and reduce staff mobility. Enugu state government should also plan to have a budget line for surveillance of AFP, and take ownership of the surveillance structure.

Evaluation of acute flaccid paralysis surveillance system, 2013 to 2017 – Bayelsa State, Nigeria

Background: Nigeria is one of the three countries where transmission of Wild Polio Virus (WPV) still occurs. Documented transmission occurs mainly in the northern part of the country. Acute flaccid paralysis (AFP) surveillance is one of polio eradication and endgame strategic plan. On this basis, we evaluated the AFP surveillance system in Bayelsa state, Nigeria with the aim of assessing the attributes of the system. Methods & Materials: We interviewed Stakeholders and reviewed AFP surveillance data from 2013 to 2017 using the updated CDC guidelines for evaluating the public health surveillance systems and the WHO performance standards to assess the performance of the system. Relevant data were extracted and analyzed using Microsoft Excel spreadsheet. Results: All 27 respondents knew that poliomyelitis was caused by a virus and they all felt that AFP case definition was easy to understand. 73% percent of them reported that completion of the Case Investigation Form (CIF) was simple. All the respondents were willing to continue to participate in the AFP surveillance. The non-polio AFP rate (12.3–16.6%) and stool specimen adequacy rate (98–100%) indicate high sensitivity. Proportion of AFP cases investigated within 48 h of notification, timely transportation, specimen arriving laboratory in good condition were all above WHO minimum standard of 80%. The surveillance system has dedicated staff from state ministry of health and support from National Stop Transmission of Polio (NSTOP). Conclusion: The AFP surveillance system in Bayelsa State is performing well. The system is useful, simple, flexible, acceptable, sensitive, representative, timely and stable. We recommended that regular training of data collectors should be implemented.

Current status of poliomyelitis in Latin America.

Oral poliovirus vaccine (OPV) has been instrumental in controlling the polio epidemic, and stands out for its safety, efficacy, ease of oral administration, and low cost. However, despite these advantages, as it is a live attenuated virus vaccine, there is the possibility of mutations that confer neurovirulence. Therefore, surveillance for acute flaccid paralysis (AFP) is important, whether associated with live vaccines (VAPP) or vaccine-derived viruses (VDPV). In this review we present important data from Latin America in recent years, where data on VDPV of community transmission, of ambiguous origin and associated with immunodeficiencies are reviewed. Due to the presence of VDPV, it is important to strengthen the epidemiological surveillance system for AFP, with data much lower than those recommended in recent years in the Americas. Additionally, it is essential to improve vaccination coverage to reduce the number of infants at risk of acquiring poliomyelitis. Consequently, we present the vaccination coverage rates with the inactivated vaccine against poliovirus (IPV) in the region and analyze the vaccination programs against poliomyelitis in accordance with the recommendations of the Latin American Society of Pediatric Infectious Diseases (SLIPE; minimum 3 doses of IPV) and the WHO Strategic Advisory Expert Group (SAGE) on Immunization (minimum 2 doses of IPV). The study concludes with recommendations from the authors for the change from OPV to exclusive use of IPV, to increase vaccination coverage and to strengthen surveillance for AFP in the region.

Two-Source Capture-Recapture Method to Estimate the Incidence of Acute Flaccid Paralysis in the Marches Region (Italy).

A combination of high infant immunization coverage and surveillance of acute flaccid paralysis (AFP) cases, plays a critical role in polio eradication. This study aimed to estimate the incidence of AFP, to evaluate the completeness of AFP ascertainment during the years, age groups and gender, and to define the main associated diagnosis among children aged under 15 in the Marches region of Italy. Analysis was performed on data from the active AFP surveillance system and the hospital discharge records in the 2006–2014 period. The two-source capture-recapture method was applied. After cross-validation, 30 AFP compatible conditions as defined by the WHO were identified, with an incidence estimate of 1.91 cases of AFP per 100,000 children under 15 years (95% CI = 1.4–2.6/100,000). Guillain–Barrè syndrome was the most common diagnosis. A significant difference (p < 0.05) has been registered in the estimated probability of case ascertainment in females. The reasons for the lower reporting of cases in females are unknown. Specific research and the implementation of a more sensitive surveillance system are essential in verifying potential inequalities and to succeed in the polio eradication initiative.