Acute Flaccid Paralysis Cases Research Articles

Clinical and Diagnostic Features of West Nile Virus Neuroinvasive Disease in New York City.

West Nile virus (WNV) neuroinvasive disease (WNND) occurs in approximately 1 percent of WNV-infected patients and typically presents as encephalitis, meningitis, or acute flaccid paralysis (AFP). WNND remains a difficult inpatient diagnosis, creating significant challenges for prognostication and therapy selection. We characterized the clinical and diagnostic features of WNND cases at two major academic medical centers in New York City in routine clinical practice. We retrospectively reviewed the charts of thirty-six patients with WNND, including twenty-six encephalitis, four meningitis, and six AFP cases. The most common presenting symptoms were fever (86.1%) and gastrointestinal symptoms (38.9%) in addition to altered mental status (72.2%), lethargy (63.9%), gait disturbances (46.2%), and headache (44.4%). Fourteen (48.3%) patients displayed acute magnetic resonance imaging (MRI) findings, particularly T2 hyperintensities in the bilateral thalami, brainstem, and deep white matter. New York State Department of Health WNV CSF IgM testing was utilized for diagnosis in 58.3% of patients; however, just 38.1% had the result by discharge, compared to 85.6% of those who underwent serum IgM testing. The median length of stay was 13.5 days, 38.9% were intubated, and three patients (8.9%) died during acute hospitalization. Our findings underscore the morbidity, mortality, and diagnostic challenges of WNND, suggesting the potential utility of serum IgM testing in combination with confirmatory CSF testing to expedite diagnosis in the acute setting.

Thirty Years of Experience of Acute Flaccid Paralysis Surveillance for Polio - China, 1993-2022.

Detecting poliovirus infections proves to be highly challenging due to their asymptomatic nature and infectious potential, highlighting the crucial importance of effective detection methods in the context of polio eradication efforts. In many countries, including China, the primary approach for identifying polio outbreaks has been through acute flaccid paralysis (AFP) surveillance. In this study, we conducted an evaluation spanning three decades (1993-2022) to assess the effectiveness of AFP surveillance in China. Data on all AFP cases identified since 1993 and national-level AFP surveillance system quality indicators aligned with the World Health Organization (WHO) standards were collected for analysis. The quality indicators assess surveillance sensitivity, completeness, timeliness of detection notification, case investigation, and laboratory workup. Surveillance sensitivity is determined by the non-polio AFP (NPAFP) detection rate among children under 15 years of age. Between 1993 and 2022, a total of 150,779 AFP cases were identified and reported. Within this pool, surveillance identified 95 cases of wild poliovirus (WPV) and 24 cases due to vaccine-derived poliovirus. From 1995 onwards, the detection rate of NPAFP cases consistently adhered to the WHO and national standards of ≥1 case per 100,000, falling between 1.38 and 2.76. Starting in 1997, all timeliness indicators consistently achieved the criteria of 80%, apart from the consistency in meeting standards set for the rate of positive specimens sent to the national laboratory. AFP surveillance has been instrumental in China's accomplishment of maintaining a polio-free status. The ongoing adherence to key performance indicators, ensuring sensitivity and prompt specimen collection, demonstrates that AFP surveillance is proficient in detecting poliovirus in China. As we move into the post-eradication phase, AFP surveillance remains crucial for the sustained absence of polioviruses in the long term.

Thirteen-year surveillance results of acute flaccid paralysis cases in Southeast Turkey and the effect of refugee movements on surveillance results.

Acute flaccid paralysis (AFP) is a major neurological problem. Turkey has accepted over 4 million refugees since 2011 due to the wars in neighbouring countries. In the long term, refugees can have adverse effects on the limited resources of health, sanitation, water supply, foodstuff, and shelter services of host countries, precipitating the transmission and spread of enteroviruses causing AFP. This study examines the 13-year surveillance and incidence of AFP cases in southeast Turkey, and questions possible impact of refugee movements on these parameters, comparing the periods before (2007-2010) and after (2011-2019) 2011, when the refugee movements emerged. The records of cases reported from southeast part of Turkey with suspected AFP between January 2007 and December 2019 were reviewed retrospectively. Of the patients, 121 (58.5%) were male. Mean age was 80.36 ± 46.67 months. Eighty-five (41.1%) were aged 60 months or younger. The number of patients under 60 months increased significantly after 2011. Mean incidence was calculated as 0.88 cases/100,000 person years versus 1.58 cases/100,000 person years in the period before and after 2011, respectively. Guillain-Barré syndrome (GBS) was the most common cause of AFP in both periods. As of 2011, however, the incidence of acute transverse myelitis increased approximately 4 times and GBS decreased proportionally. Non-polio enteroviruses were the most frequent isolates, detected from 9.1% of stool samples. Although refugee movements appear to may have adverse effects on AFP incidence and surveillance outcomes, larger studies involving the whole country, particularly at places where no refugees settled, are needed to achieve more conclusive evidence.

Validation of improved automated nucleic acid extraction methods for direct detection of polioviruses for global polio eradication

Polioviruses (PV), the main causative agent of acute flaccid paralysis (AFP), are positive-sense single-stranded RNA viruses of the family Picornaviridae. As we approach polio eradication, accurate and timely detection of poliovirus in stool from AFP cases becomes vital to success for the eradication efforts. Direct detection of PV from clinical diagnostic samples using nucleic acid (NA) extraction and real-time reverse transcriptase polymerase chain reaction (rRT-PCR) instead of the current standard method of virus isolation in culture, eliminates the long turn-around time to diagnosis and the need for high viral titer amplification in laboratories. An essential component of direct detection of PV from AFP surveillance samples is the efficient extraction of NA. Potential supply chain issues and lack of vendor presence in certain areas of the world necessitates the validation of multiple NA extraction methods. Using retrospective PV-positive surveillance samples (n=104), two extraction kits were compared to the previously validated Zymo Research Quick-RNA™ Viral Kit. The Roche High Pure Viral RNA Kit, a column-based manual extraction method, and the MagMaX™ Pathogen RNA/DNA kit used in the automated Kingfisher Flex system were both non-inferior to the Zymo kit, with similar rates of PV detection in pivotal rRT-PCR assays, such as pan-poliovirus (PanPV), poliovirus serotype 2 (PV2), and wild poliovirus serotype 1 (WPV1). These important assays allow the identification and differentiation of PV genotypes and serotypes and are fundamental to the GPLN program. Validation of two additional kits provides feasible alternatives to the current piloted method of NA extraction for poliovirus rRT-PCR assays.

Epidemiological Surveillance of Acute Flaccid Paralysis for Eradication of Poliomyelitis (A Brief Review)

Abstract In May 1988 the World Health Assembly set to World Health Organization (WHO) the goal to achieve a global eradication of poliomyelitis by the year 2000. Surveillance of the acute flaccid paralysis (AFP) remains the ‘gold standard’ for the detection of polio. The criterion of sensitivity of the surveillance system is the incidence from non-polio related AFP, in children under 15 years of age. The aim is to detect more than 1 case of AFP, per 100,000 children. In 2019, WHO announced the eradication of wild poliovirus 3, and poliovirus 2 was eradicated in 2015. Wild poliovirus 1 continues to circulate. The main goals of the WHO Polio Eradication Strategy for the period 2022-2026 are: permanently interrupt all poliovirus transmission in endemic countries (Afghanistan and Pakistan), stop cVDPV (circulating vaccine-derived poliovirus) transmission and prevent outbreaks in non-endemic countries.

Evaluation of the environmental polio surveillance system-Northern Region, Ghana, 2021.

Acute Flaccid Paralysis (AFP) surveillance is the gold standard in the polio eradication initiative. The environmental component of polio surveillance can detect circulating Polioviruses from sewage without relying on clinical presentation. The effectiveness of the Environmental Surveillance (ES) is crucial to global polio eradication. We assessed the usefulness and attributes of the ES system in the Northern region and determined if the system is meeting its objectives. We conducted a descriptive cross-sectional evaluation in the Northern region from 2019 to 2020 using the updated US Centers for Disease Control and Prevention guideline. We interviewed stakeholders, reviewed records, and observed surveillance activities from 29th March to 7th May, 2021. Quantitative data were analyzed manually as frequencies and proportions whiles thematic analysis was used for the qualitative data. One of 48 (2.1%) samples collected tested positive for circulating vaccine-derived Poliovirus (cVDPV). The cVDPV detection triggered enhanced AFP surveillance that resulted in the identification of a case of AFP. Three rounds of polio vaccination campaigns were organized. All surveillance officers interviewed were willing to continue providing their services for the ES. Reporting form has few variables and is easy to complete. The completeness of forms was 97.9% (47/48). Samples collected were dispatched on the same day to the testing laboratory. The system's data was managed manually. The system was useful in detecting polio outbreaks. Data quality was good, the system was simple, flexible, acceptable, representative, and fairly stable. Sensitivity was high but predictive value positive was low. Timeliness in reporting was good but feedback from the national level could not be assessed. There is a need to improve on the feedback system and ensure that, the surveillance data is managed electronically.

Lower Limb Paralysis Associated with Chikungunya in Kinshasa, the Democratic Republic of the Congo: Survey Report.

Polio-associated paralysis is one of the diseases under national surveillance in the Democratic Republic of the Congo (DRC). Although it has become relatively rare due to control measures, non-polio paralysis cases are still reported and constitute a real problem, especially for etiological diagnosis, which is necessary for better management and response. From September 2022 to April 2023, we investigated acute flaccid paralysis (AFP) cases in Kinshasa following an alert from the Provincial Division of Health. All suspected cases and their close contacts were investigated and sampled. Among the 57 sampled patients, 21 (36.8%) were suspects, and 36 (63.2%) were contacts. We performed several etiological tests available in the laboratory, targeting viruses, including Poliovirus, Influenza virus, SARS-CoV-2, Enterovirus, and arboviruses. No virus material was detected, but the serological test (ELISA) detected antibodies against Chikungunya Virus, i.e., 47.4% (27/57) for IgM and 22.8% (13/57) for IgG. Among suspected cases, we detected 33.3% (7/21) with anti-Chikungunya IgM and 14.3% (3/21) of anti-Chikungunya IgG. These results highlight the importance of enhancing the epidemiological surveillance of Chikungunya.

The Polio Vaccination Status of Non-polio Acute Flaccid Paralysis Cases in the Far North Region of Cameroon: A Five-Year Retrospective Study From 2015 to 2019.

The Expanded Program on Immunization (EPI) of Cameroon contributes to the reduction of polio, but the rate of non-polio acute flaccid paralysis (NPAFP) is still high. The aim of this study was to describe the immunization profile ofNPAFP cases and the performance of polio surveillance in the Far North Region of Cameroon between 2015 and 2019. A retrospective secondary data analysis was conducted using the national EPI and regional AFP surveillance case-based database from 2015 to 2019. Analyses were carried out using Epi-Info statistical software (version 7) (Centers for Disease Control and Prevention, Atlanta, GA). The surveillance network of the region reported 848 cases of NPAFPbetween 2015 and 2019. The sex distribution of the AFP cases revealed that 43.3% were females and 56.7% were males. Cases with AFP aged less than five years accounted for the largest proportion of cases (67.2%). Overall, 733/848 (86.4%) of the AFP cases received at least three doses of the oral polio vaccine (OPV). The AFP detection rate substantially increased in the region after the introduction of community-based surveillance in 2016. The mean NPAFP level during the study period was 7.3/100,000 children aged less than 15 years. The mean proportion of AFP cases with two adequate stools was 668/848 (78.7%), and the mean proportion of stools to the national reference laboratory within three days was 466/848 (54.9%). Only 86.4% of AFP cases received three or more doses of OPV required for immunization. The stool specimen management indices were not good enough to confirm that no case of poliovirus was missed in the laboratory. To strengthen the country's polio-free status, surveillance should be strengthened in least-performing health districts to improve the quality of AFP case investigations after detection.

Effective partnership and in-country resource mobilization in Sudan for cVDPV2 outbreak response amid multiple emergencies in 2020-2021.

During 2020 and immediately prior to the COVID-19 pandemic, Sudan was experiencing multiple emergencies including violence, seasonal flooding, and vector-borne disease outbreaks. After more than ten years since its last case of wild poliovirus, Sudan declared a circulating vaccine-derived poliovirus type 2 (cVDPV2) outbreak on 9 August 2020. cVDPV2 outbreak response data and programme documents of the Federal Ministry of Health and WHO were reviewed. Surveillance data was verified through WHO-recommended procedures for detecting and characterizing polioviruses from stool and sewage samples collected from acute flaccid paralysis (AFP) cases and the environment. This outbreak in Sudan led to a total of 58 confirmed cases of cVDPV2 from 15 of the 18 states. Two nationwide vaccination campaigns were held to increase immunity of children under-five against poliovirus type 2. Funding challenges were overcome by intense additional resource mobilization from in-country sources. The funding gap was bridged from domestic resources (49%) sourced through GPEI partners, and in-country humanitarian funding mechanisms. During an outbreak response and challenge of funding shortfall, mobilizing in-country resources is possible through coordinated approaches, regular communication with partners, disaggregation of needs, and matching in-kind and financial support to fill gaps. A cVDPV2 outbreak requires a fast, resourced, and quality response to stop virus circulation.

Non-Polio Enteroviruses Isolated by Acute Flaccid Paralysis Surveillance Laboratories in the Russian Federation in 1998-2021: Distinct Epidemiological Features of Types.

More than 100 types of non-polio enteroviruses (NPEVs) are ubiquitous in the human population and cause a variety of symptoms ranging from very mild to meningitis and acute flaccid paralysis (AFP). Much of the information regarding diverse pathogenic properties of NPEVs comes from the surveillance of poliovirus, which also yields NPEV. The analysis of 265 NPEV isolations from 10,433 AFP cases over 24 years of surveillance and more than 2500 NPEV findings in patients without severe neurological lesions suggests that types EV-A71, E13, and E25 were significantly associated with AFP. EV-A71 was also significantly more common among AFP patients who had fever at the onset and residual paralysis compared to all AFP cases. In addition, a significant disparity was noticed between types that were common in humans (CV-A2, CVA9, EV-A71, E9, and E30) or in sewage (CVA7, E3, E7, E11, E12, and E19). Therefore, there is significant evidence of non-polio viruses being implicated in severe neurological lesions, but further multicenter studies using uniform methodology are needed for a definitive conclusion.

Effectiveness of poliovirus vaccines against circulating vaccine-derived type 2 poliomyelitis in Nigeria between 2017 and 2022: a case-control study

Between 2018 and 2022, Nigeria experienced continuous transmission of circulating vaccine-derived type 2 poliovirus (cVDPV2), with 526 cases of cVDPV2 poliomyelitis detected in total and approximately 180 million doses of monovalent type 2 oral poliovirus vaccine (mOPV2) and 450 million doses of novel type 2 oral poliovirus vaccine (nOPV2) delivered in outbreak response campaigns. Inactivated poliovirus vaccine (IPV) was introduced into routine immunisation in 2015, with a second dose added in 2021. We aimed to estimate the effectiveness of nOPV2 against cVDPV2 paralysis and compare nOPV2 effectiveness with that of mOPV2 and IPV. In this retrospective case-control study, we used acute flaccid paralysis (AFP) surveillance data in Nigeria from Jan 1, 2017, to Dec 31, 2022, using age-matched, onset-matched, and location-matched cVDPV2-negative AFP cases as test-negative controls. We also did a parallel prospective study from March, 2021, using age-matched community controls from the same settlement as the cases. We included children born after May, 2016, younger than 60 months, for whom polio immunisation history (doses of OPV from campaigns and IPV) was reported. We estimated the per-dose effectiveness of nOPV2 against cVDPV2 paralysis using conditional logistic regression and compared nOPV2 effectiveness with that of mOPV2 and IPV. In the retrospective case-control study, we identified 509 cVDPV2 poliomyelitis cases in Nigeria with case verification and paralysis onset between Jan 1, 2017, and Dec 31, 2022. Of these, 82 children were excluded for not meeting inclusion criteria, and 363 (85%) of 427 eligible cases were matched to 1303 test-negative controls. Cases reported fewer OPV and IPV doses than test-negative controls (mean number of OPV doses 5·9 [SD 4·2] in cases vs 6·7 [4·3] in controls; one or more IPV doses reported in 95 [26%] of 363 cases vs 513 [39%] of 1303 controls). We found low per-dose effectiveness of nOPV2 (12%, 95% CI -2 to 25) and mOPV2 (17%, 3 to 29), but no significant difference between the two vaccines (p=0·67). The estimated effectiveness of one IPV dose was 43% (23 to 58). In the prospective study, 181 (46%) of 392 eligible cases were matched to 1557 community controls. Using community controls, we found a high effectiveness of IPV (89%, 95% CI 83 to 93, for one dose), a low per-dose effectiveness of nOPV2 (-23%, -45 to -5) and mOPV2 (1%, -23 to 20), and no significant difference between the per-dose effectiveness of nOPV2 and mOPV2 (p=0·12). We found no significant difference in estimated effectiveness of the two oral vaccines, supporting the recommendation that the more genetically stable nOPV2 should be preferred in cVDPV2 outbreak response. Our findings highlight the role of IPV and the necessity of strengthening routine immunisation, the primary route through which IPV is delivered. Bill & Melinda Gates Foundation and UK Medical Research Council.

Monitoring the evolution of vaccine-derived poliovirus in East and Southern African countries, 2010 - 2021.

the Africa region was certified indigenous wild poliovirus-free in August 2020. Countries in East and Southern Africa have, during acute flaccid paralysis (AFP) and environmental surveillance (ES), detected equally concerning vaccine-derived polioviruses (VDPVs) that have not been systematically documented to guide programming in the sub-region. The study documents trends and salient observations of the VDPVs by country of detection, for 11 years from 2010 to 2021. we conducted secondary data analysis, a descriptive study design, by deploying field and laboratory of AFP and environmental surveillance databases of the 20 East and Southern African countries from 2010 to 2021. a total of 318 VDPVs were reported over the study period. The majority were from AFP cases (58.8%) and the rest equally distributed between healthy community children and environmental surveillance sources. More polioviruses were detected after 2016 than during the period before. We observed that more boys were affected by VDPVs compared to girls. Children under 5 years were more affected than other age groups, with a mean age of 3.6 years. Delay of samples in the field seemed to increase the likelihood of not reporting VDPVs and not mounting timely public health detailed investigations and vaccination responses. the study provides useful evolutional trends of VDPVs for surveillance and vaccination programming. We also noted that the VDPV2s have been increasing after the 2016 tOPV to oral polio vaccine (bOPV) switch. The COVID-19 pandemic emergence in 2020, led to a decline in AFP, ES surveillance, and immunization activities. Our findings point to the need to implement enhanced tailored childhood immunization recovery strategies and to speed up the use of inactivated polio vaccine (IPV) to boost population immunity.

Non-polio enteroviruses circulation in acute flaccid paralysis cases and sewage in Senegal from 2013 to 2021

ObjectivesSeveral factors can cause acute flaccid paralysis cases including non-polio enteroviruses. In Senegal, few studies on non-polio enteroviruses (NPEV) have been performed. MethodsOur study assess the molecular epidemiology of non-polio enteroviruses in Senegal from 2013 to 2021 through the previously existing programs for surveillance of polioviruses. ResultsA total of 3815 stool samples and 281 sewage samples were collected. After virus isolation by cell culture, non-polio enteroviruses-positive isolates were confirmed by reverse transcriptase-quantitative polymerase chain reaction. Following this detection, the positive samples were subjected to molecular characterization. Our data showed that 15.22% and 52.66% were positive in cell culture for non-polio enteroviruses in acute flaccid paralysis surveillance and environmental surveillance, respectively. These non-polio enteroviruses-positive isolates were detected all year round but tend to unequal peaks of circulation, and the age group 0-5 years was more vulnerable to infection (84.4%). Genetic characterization revealed the circulation of enteroviruses species infecting humans (Enterovirus A – Enterovirus D): Enterovirus A (29.2%) and Enterovirus B (63.1%) isolates from both the acute flaccid paralysis surveillance and environmental surveillance while Enterovirus C (5.3%) and Enterovirus D (2.4%) were only isolated from the acute flaccid paralysis surveillance. However, the highly prevalent Enterovirus B species from the acute flaccid paralysis surveillance included echovirus 7 and echovirus 13, whereas coxsackievirus A6 was the predominant species from the environmental surveillance. ConclusionThis first 8-year period study of NPEV in Senegal showed that NPEV represent important viral etiologies associated with acute flaccid paralysis cases and circulating in environmental surveillance in Senegal and highlighted the need to promote effective long-term strategies for monitoring of non-polio enteroviruses infections.

Evaluation of the Acute flaccid paralysis surveillance indicators in Zambia from 2015–2021: a retrospective analysis

BackgroundThe resurgence of poliovirus infection in previously polio free regions and countries calls for renewed commitment to the global polio eradication efforts including strengthening of Acute Flaccid Paralysis (AFP) surveillance systems. Zambia is one of the countries substantially at risk for the importation of poliovirus infection from neighbouring countries including Malawi, Mozambique, and Democratic Republic of the Congo (DRC). This study describes a seven-year AFP surveillance, assesses the surveillance indicators, and highlights areas for improvement.MethodsWe conducted retrospective analysis of the routinely collected AFP surveillance data from January 2015 to December 2022. The AFP surveillance indicators performance was assessed using the World Health Organisation’s recommended minimum AFP surveillance indicators performance.ResultsCumulatively, a total of 1715 AFP cases were reported over the study period. More than half, 891 (52%) of reported cases were aged < 5 years with 917 (53.5%) of males. More than half, 1186 (69.2%) had fever at onset, 718 (41.9%) had asymmetric paralysis and 1164 (67.9%) had their paralysis progressed within 3 days of onset. The non-polio AFP rate ranges from 3.4 to 6.4 per 100,000 children < 15 years old and stool adequacy ranging from 70.9% to 90.2% indicating sensitive surveillance with late detection of cases. The percentage of cases with early stool collection, timely transportation was above the World Health Organisation (WHO) minimum of 80% but with declining proportion of stools arriving in the laboratory in optimal condition. Completeness of 60-days follow-up evaluation was suboptimal ranging from 0.9% to 28.2%.ConclusionThe AFP surveillance system in Zambia is doing well. However, additional efforts are needed to improve early detection of cases; stool sample collection, transportation and monitoring to ensure arrival in good condition in the laboratory; and improve 60-days follow-up evaluation for evidenced-based classification of inadequate AFP cases and proper care.

Acute flaccid paralysis surveillance system data analysis, Pujehun, Sierra Leone, 2011-2020

The Acute Flaccid Paralysis (AFP) surveillance system was established to detect poliovirus and to measure progress toward Poliovirus eradication. Vaccine-derived poliovirus outbreaks have been reported worldwide in 2020, including in Sierra Leone. We analyzed AFP surveillance data to describe the distribution, epidemiological trend, and clinical characteristics of AFP cases. We analyzed secondary data of AFP cases in the Pujehun District for the period from 2011 to 2020. We collected data on key variables such as age, sex, clinical characteristics, outcome, non-AFP rate, stool adequacy, and non-Polio enteroviruses. We analyzed data using Microsoft Excel 2013 and Epi-Info 7 software. Results were reported in tables, graphs, and maps. A total of 60 AFP cases were reported with a median age of 3 years (range 0.7- 14), with no confirmed poliomyelitis. Under-five Children accounted for 46 (76.7%), with 27 females and 33 males. Of the sixty cases,17(28.3%) were hospitalized and 16(27%) were detected in the hospital. Ten (16.7%) cases were classified as non-Polio enteroviruses and 50 (83.3%) as negative. Sudden onset of paralysis was reported in 57 (96.6%) cases, paralysis progressed within 3 days in 44 (74.6%) cases, and 56 (94.6%) reported fever. Out of 33, the left legs 28 (84.9%) were the most affected sites. Majority of the cases, 35(58.1%) had received five and more doses of the Oral Polio vaccine. The stool adequacy was 54(90%) and the non-AFP rate was above 2.0 except in 2017 when it was 1.8. Of the 14 chiefdoms,12 (86%) met the minimum AFP reporting target (1/100,000 &lt; 15 years’ population). None of the AFP cases were confirmed as Poliovirus in Pujehun District. Case detection and reporting rate were high except for two chiefdoms. We recommended maintaining the AFP surveillance system in the district and replicate the strategies used to other districts.

Clinical and epidemiological characteristics of acute flaccid myelitis cases in children registered in the Russian Federation in 2015–2019

Acute flaccid myelitis is a syndrome characterized as the development of acute flaccid paralysis of one or more limbs due to lesions of the anterior horns of the spinal cord, which occurs against the background of a viral infection. More than 300 acute flaccid paralysis cases are registered in the Russian Federation annually, most of them are of a non-infectious etiology. In some cases, patients develop a complex of symptoms similar to poliomyelitis, but without isolation of polioviruses from stool samples. Clinical characteristics of such cases include acute onset, fever, persistent peripheral asymmetric paresis/paralysis of predominantly proximal parts of the limbs, and absence of pathological reflexes, pelvic disturbances, or pyramidal symptoms. In literature, such complex of symptoms is referred as acute flaccid myelitis. We provide an analysis of 18 cases of acute flaccid myelitis detected in the Russian Federation in the period from 2015 to 2019. A clear seasonality of the disease from July to November was noted. Studies of faecal samples, cerebrospinal fluid and blood samples did not reveal the pathogen. In all patients, regardless of therapy, there was a positive trend, but complete recovery was not achieved: paresis of varying severity persisted, mainly in the proximal extremities Therefore, acute flaccid myelitis cases as acute flaccid paralysis cases of unknown etiology require an additional observation and an expanded algorithm of laboratory investigation aimed to finding a possible pathogen.

Poliomyelitis alert on Tunisian borders: response and challenges

Abstract Introduction Poliomyelitis, which disappeared in Tunisia 30 years ago, should be the second disease to be eradicated after smallpox. However, a few endemic foci persist and its recent detection in some regions is causing great concern. On January 11, 2023, Tunisia received an alert with the notification of 2 polio cases in Algeria, the second of which was detected in November 2022 at about 400 KM from Tunisia. The objective of this study is to describe the results of the investigations following this alert as well as the prevention and response measures triggered. Methods We conducted an active search for acute flaccid paralysis (AFP) cases in all governorates and a retrospective search for possible unreported AFP cases hospitalized from November 1, 2022. Vaccination coverage was verified for catch-up if incomplete vaccination. Surveillance of poliovirus shedding in patients with primary immunodeficiencies (PIDs) was also conducted as well as other public health measures. Results As of April 20, 2023, 38 AFP cases have been reported through active search. Retrospective hospital-based surveillance has revealed 31 cases. In addition, 3142 children with deficient vaccination were identified, distributed differently by region. All of them were caught up with Inactivated polio vaccine (IPV). A total of 90 PIDs were followed up. The replacement of the Oral polio vaccine (OPV) dose at 6 months by IPV in the national immunization schedule as well as a request for verification of the possibility of using the new OPV2 in Tunisia and of the required requirements were made. Conclusions The risk of poliomyelitis resurgence in our country is not negligible. Sustained vigilance is necessary, particularly through ensuring high vaccination coverage and effective surveillance to rapidly detect any imported case. This is essential in view of the global context and the existence of outbreaks especially in certain African countries with which several exchanges and migratory flows remain. Key messages • The Poliomyelitis alert on Tunisian borders in January 2023 is a real threat, that should also be taken into consideration by neighboring countries. • Sustained vigilance is necessary, particularly through effective surveillance and appropriate vaccination strategy.

Genetic characterizations and molecular epidemiology of human echovirus 30 isolated from Ningxia, China

In October 2017, a small outbreak of echovirus 30 (E30) associated with aseptic meningitis in nine cases occurred at a primary school in the Ningxia Hui Autonomous Region. That year, we observed a significant increase in E30 levels in an acute flaccid paralysis (AFP) case surveillance system. To investigate their phylogenetic relationships, we determined the whole genomic sequences of 12 strains isolated from aseptic meningitis cases, AFP cases, and healthy children. We found that the E30 strains circulating in Ningxia belong to two lineages (H and J). The strains isolated in 2010, 2012, and 2016 belonged to the H lineage. In 2017, a new lineage, J, emerged as the dominant lineage. Phylogenetic trees were constructed based on the whole genome and P1, P2, and P3 regions; clustering with other types of enterovirus species B was found, suggesting that recombination events had occurred. The recombination sites were mainly in regions 2B, 2C, and 3D. This study confirmed that the E30 strains in Ningxia in 2010, 2012, and 2016 had different recombination patterns and were recombined with different enteroviruses. The 2017 epidemic E30 originated from another new lineage with a complex recombination pattern and formed an independent transmission chain in Ningxia.

Evaluation of Direct Detection Protocols for Poliovirus from Stool Samples of Acute Flaccid Paralysis Patients.

Polio surveillance in the Global Polio Eradication Initiative has been conducted with virus isolation from stool samples of acute flaccid paralysis (AFP) cases. Under the current biorisk management/regulations, challenges arise in the timelines of the report, sensitivity of the test and containment of poliovirus (PV) isolates. In the present study, we evaluated protocols of previously reported direct detection (DD) methods targeting the VP1 or VP4-VP2 regions of the PV genome in terms of sensitivity and sequencability. An optimized protocol targeting the entire-capsid region for the VP1 sequencing showed a high sensitivity (limit of detection = 82 copies of PV genome) with a simpler and faster reaction than reported ones (i.e., with the addition of all the primers at the start of the reaction, the RT-PCR reaction finishes within 2.5 h). The DD methods targeting the VP1 region detected PV in 60 to 80% of PV-positive stool samples from AFP cases; however, minor populations of PV strains in the samples with virus mixtures were missed by the methods. Sequencability of the DD methods was primarily determined by the efficiency of the PCRs for both Sanger and nanopore sequencing. The DD method targeting the VP4-VP2 region showed higher sensitivity than that targeting the VP1 region (limit of detection = 25 copies of PV genome) and successfully detected PV from all the stool samples examined. These results suggest that DD methods are effective for the detection of PV and that further improvement of the sensitivity is essential to serve as an alternative to the current polio surveillance algorithm.

Analysis of Registered Cases of Acute Flaccid Paralysis in Stara Zagora District as a Part of Polio Eradication Strategy

Abstract Poliomyelitis is the infection that, after smallpox, is a “serious candidate” for eradication worldwide. In accordance with the WHO strategy for 2022-2026, epidemiological surveillance of acute flaccid paralysis (AFP) is carried out with the aim of poliomyelitis eradication. The aim of the study is to determine the risk factors for the occurrence of AFP in children up to 15 years of age and to analyze the effectiveness of the established system for epidemiological surveillance of AFP, in Bulgaria. Materials and methods. All cases of AFP for the monitoring period 2012-2021, in Stara Zagora district, were studied. A questionnaire (34 questions) for sociodemographic and lifestyle possible risk factors for developing of AFP was also completed. Retrospective, descriptive and analytic cross-sectional epidemiological methods were applied. The data were analyzed using SPSS Statistics, Version 25.0 (IBM Corp. Armonk, NY, USA) (with Fisher’s exact test). Results. There were 81 cases of Facial paralysis only, registered in the Web based system for surveillance of AFP, for Stara Zagora region, and 11 – AFP (without facial paralysis), for the period 2012-2021, in Stara Zagora district (92 in total). The protective factors for developing of AFP from our study were significantly associated to: having no history of paresis or paralysis in the past; absence of trauma; presence of central sewage near the home; absence of contact with animals; absence of consumption of unwashed fruits and vegetables. Conclusion. It is very important to carry out systematic surveillance of AFP, in children up to 15 years, with the aim of investigating all cases as part of the Global strategy for the eradication of poliomyelitis; monitoring of the immunization coverage with polio vaccine to maintain a high level; surveillance of the waste and sewage waters, twice during the year in 6 months.