Retrospective Analysis of Six Years of Acute Flaccid Paralysis Surveillance and Polio Vaccine Coverage Reported by Italy, Serbia, Bosnia and Herzegovina, Montenegro, Bulgaria, Kosovo, Albania, North Macedonia, Malta, and Greece

Here we analyzed six years of acute flaccid paralysis (AFP) surveillance, from 2015 to 2020, of 10 countries linked to the WHO Regional Reference Laboratory, at the Istituto Superiore di Sanità, Italy. The analysis also comprises the polio vaccine coverage available (2015–2019) and enterovirus (EV) identification and typing data. Centralized Information System for Infectious Diseases and Laboratory Data Management System databases were used to obtain data on AFP indicators and laboratory performance and countries’ vaccine coverage from 2015 to 2019. EV isolation, identification, and typing were performed by each country according to WHO protocols. Overall, a general AFP underreporting was observed. Non-Polio Enterovirus (NPEV) typing showed a high heterogeneity: over the years, several genotypes of coxsackievirus and echovirus have been identified. The polio vaccine coverage, for the data available, differs among countries. This evaluation allows for the collection, for the first time, of data from the countries of the Balkan area regarding AFP surveillance and polio vaccine coverage. The need, for some countries, to enhance the surveillance systems and to promote the polio vaccine uptake, in order to maintain the polio-free status, is evident.

Sensitivity of the acute flaccid paralysis surveillance system for poliovirus in South Africa, 2016–2019

Introduction. Global poliovirus eradication is a public health emergency of international concern. The acute flaccid paralysis (AFP) surveillance programme in South Africa has been instrumental in eliminating polioviruses and keeping the country poliovirus free. Gap statement. The sensitivity of surveillance for polioviruses by every African country is of global interest in the effort to ensure global health security from poliovirus re-emergence. Aim. To describe the epidemiology of polioviruses from AFP cases and environmental samples in South Africa and to report the performance of the AFP surveillance system for the years 2016–2019 against targets established by the World Health Organization (WHO). Methods. Stool specimens from AFP or suspected AFP cases were received and tested as per WHO guidelines. Environmental samples were gathered from sites across the Gauteng province using the grab collection method. Concentration was effected by the two-phase polyethylene glycol method approved by the WHO. Suspected polioviruses were isolated in RD and/or L20B cell cultures through identification of typical cytopathic effects. The presence of polioviruses was confirmed by intratypic differentiation PCR. All polioviruses were sequenced using the Sanger method, and their VP1 gene analysed for mutations. Results. Data from 4597 samples (2385 cases) were analysed from the years 2016–2019. Two cases of immunodeficiency-associated vaccine-derived poliovirus (iVDPV) type 3 were detected in 2017 and 2018. A further 24 Sabin type 1 or type 3 polioviruses were detected for the 4 years. The national surveillance programme detected an average of 3.1 cases of AFP/100 000 individuals under 15 years old (2.8/100 000–3.5/100 000). The stool adequacy of the samples received was 53.0 % (47.0–55.0%), well below the WHO target of 80 % adequacy. More than 90 % of results were released from the laboratory within the turnaround time (96.6 %) and non-polio enteroviruses were detected in 11.6 % of all samples. Environmental surveillance detected non-polio enterovirus in 87.5 % of sewage samples and Sabin polioviruses in 12.5 % of samples. Conclusion. The AFP surveillance programme in South Africa is sensitive to detect polioviruses in South Africa and provided no evidence of wild poliovirus or VDPV circulation in the country.

Acute Flaccid Paralysis surveillance in Polio Eradication and Beyond: Learning from Bangladesh

IntroductionGlobal Polio Eradication Initiative, GPEI led by the World Health Organization (WHO), helped to develop standard acute flaccid paralysis surveillance (AFP) system worldwide, including Bangladesh, which comprises infrastructure, knowledge, expertise, funding, technical assistance, and trained personnel. AFP surveillance can complement any disease surveillance systems, and many countries are now utilizing these polio surveillance assets for monitoring other vaccine-preventable diseases. This paper outlines how AFP surveillance has evolved in Bangladesh over time, its success and challenging factors, and its potential to accomplish other health goals.MethodologyThis mixed-method study includes a grey literature review, a survey for quantitative and qualitative information on barriers and facilitators, and Key Informant Interviews (KIIs) to gather relevant in-depth information on AFP surveillance in Bangladesh. Grey literature was collected online and paper documentation from different stakeholders. Online and in-person surveys were conducted in six divisions of Bangladesh, including Dhaka, Rajshahi, Rangpur, Chittagong, Sylhet, and Khulna, to map tacit knowledge ideas, approaches, and experiences. KIIs were conducted at global, national, and sub-national levels. Data were then combined on focused emerging themes, including history, challenges, and successes of the AFP surveillance system in Bangladesh.ResultsAFP surveillance in Bangladesh was first introduced in 1990 at the district and Upazila level major hospitals. High population growth, low performance, hard-to-reach areas, and groups of people residing in risky zones were major challenges to implementing this surveillance system. Surveillance was gradually enriched by establishing certification standards and community-based AFP surveillance and improved Surveillance Immunization Medical Officer (SIMO) network activities, laboratory activities, and proper monitoring and evaluation. In Bangladesh, a national disease surveillance system and a laboratory are now being used for multiple diseases, including polio, measles, Japanese Encephalitis, Neonatal Tetanus etc.ConclusionIn Bangladesh, it is evident that the AFP surveillance system is supporting the health system more broadly by building knowledge, experience, and assets and forming a strong platform for other health programs. In addition, its strengths can be leveraged for combating new and emerging diseases like COVID-19. However, the sustainability of the AFP surveillance in Bangladesh still needs collaborative support from partners, mainly technical assistance.

Evaluation of acute flaccid paralysis surveillance indicators in Sokoto state, Nigeria, 2012–2019: a secondary data analysis

Background Nigeria, 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. Methods This 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. Results Cumulatively, 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. Conclusions Sokoto 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.

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.

Impact of the protracted war on performance of Acute Flaccid Paralysis Surveillance System Indicators, Yemen: 2014-2017 (Preprint)

BACKGROUND Highly sensitive acute flaccid paralysis surveillance (AFP), which include immediate case investigation, and specimen collection are critical for reaching polio global 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 polio free country in 2009, the protracted war since 2015 put the country at risk for polio re-emergence OBJECTIVE to evaluate the performance of the Yemen AFPSS at both national and governorate levels and to assess the impact of the ongoing war on the performance METHODS Retrospective descriptive analysis was conducted on Yemen secondary AFP surveillance data for the years 2014 (before the war) and 2015-2017 (during the war). Data consisting of all children <15years reported as AFP. AFP surveillance performance was evaluated using WHO-specified AFP surveillance indicators RESULTS At the national level, all indicators were met before and after the war except for the “Lab results received ≤ 28 days” that was unmet since the war erupted. Furthermore, the “Stool specimens arriving at central level ≤3 days” was unmet after the war but only in 2017. At the governorate level, although the “Adequacy” and "Stool specimens arriving at laboratory in good condition” indicators were met before the war in all governorates, the first indicator was unmet in 9 (41%) governorates since the war erupted and the second was unmet in 9 governorates (41%) but only in 2017 CONCLUSIONS Findings showed that some of the AFP indicators was negatively impacted by eruption of the war due to closure of the Sana'a capital airport and postponement of samples during shipment to the reference laboratory under poor storage condition. To ensure rapid detection of any polio cases, improving specimens’ collection, storage, and transportation together with proper and timely specimens' shipment to the reference laboratory should be considered