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

Introduction: in 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. Methods: secondary 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. Results: administrative 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%. Conclusion: South 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.

Changing epidemiology of yellow fever virus in Oyo State, Nigeria.

BACKGROUND: Yellow Fever is an acute viral hemorrhagic disease endemic in tropical Africa and Latin America and is transmitted through infected mosquitoes. The earliest outbreak of yellow fever in Nigeria was reported in Lagos in 1864 with subsequent regular outbreaks reported until 1996. A large epidemic of yellow fever occurred in Oyo State in April and May 1987 following an epidemic of sylvatic yellow fever in Eastern Nigeria the previous year. For 21 years, no further confirmed cases were reported until September 2017 following which Nigeria has been responding to successive outbreaks. The renewed onset of yellow fever outbreaks in Nigeria followed a global trend of reports and from other African countries. Yellow Fever disease has no cure, but control is through vaccination and vector control. Eliminating Yellow fever Epidemic (EYE) strategy to improve high-risk countries' prevention, preparedness, detection, management, and response to yellow fever outbreaks was developed by the WHO in 2017 and launched in Nigeria in April 2018. Yet, poor vaccination coverage continues to be a cause for concern. MATERIALS AND METHODS: We conducted a retrospective cross-sectional study that examines the resurgence of Yellow fever cases and outbreaks from 2013 to 2020 in Oyo State, Nigeria. The Yellow Fever data for both surveillance and routine Expanded Programme on Immunization (EPI) were the focus of the review. Surveillance data were retrieved from the State's database reported by all 33 LGAs, maintained by the State and supported by the World Health Organization at the Zonal and State levels. The routine EPI data were retrieved from District Health Information Software (DHIS_2). The proportion of LGAs reporting at least one case of suspected yellow fever with a blood specimen and the number of suspected cases reported for each year within the period under review was measured. We also assessed the trend of confirmed cases and the incidence per 100,000 persons. Also, suspected cases of yellow fever were categorized into four age groups and their vaccination status was assessed. The State's annual administrative routine vaccination coverage for yellow fever vaccine was compared with the number of confirmed cases for each year. RESULTS: The proportion of LGAs reporting at least a case of suspected yellow fever, with blood samples collected, ranged from 6.1 to 84.9% between 2014 and 2020 while a total of 9 confirmed (8 cases) and probable (1 case) cases of yellow fever were recorded. However, there were no confirmed cases from the year 2013 to 2016, including 2018 but an upward trend of incidence of the disease per 100,000 persons from 0% to 2013 through 2018, to 3.5% in 2019, and then to 5.6% in 2020 was observed. 93 of 240 (39%) suspected yellow fever cases reported during the given period were observed to have received yellow fever vaccine. CONCLUSIONS: In conclusion, the increase in the circulation of the yellow fever virus in the state reiterates the state is at a high risk of yellow fever transmission and underlines the need for viable interventions such as environmental hygiene to rid the environment of the disease vector's ecological niche and improving routine EPI coverage to provide population immunity.

Distribution pattern of poliovirus potentially infectious materials in the phase 1b medical laboratories containment in conformity with the global action plan III.

BACKGROUND: The containment of poliovirus infectious/potentially infectious materials in all biomedical facilities in Nigeria remain crucial to maintaining gains recorded towards polio eradication. Activities involved in the Nigerian Poliovirus type 2-laboratory containment survey in line with the 3rd Global Action Plan III (GAP III) for poliovirus containment are documented in this study. Through these activities, the overall preparedness for poliovirus eradication in Nigeria is assessed. METHOD: A cross-sectional survey was conducted from 19th September-31st October 2016 using structured Laboratory survey and inventory (LSI) questionnaires uploaded onto the SPSS software package in 560 biomedical facilities classified either as high risk or medium risk facilities across the 6 zones in Nigeria. RESULTS: In total, 560 biomedical facilities were surveyed in Nigeria in conformity with the GAP III. In total, 86% of the facilities surveyed were with laboratories while 14% were without laboratories. Twelve laboratories with poliovirus potentially infectious materials were identified in this exercise. In total, 50% of the 12 laboratories were under the ministry of education for research purposes. While 33% were among those laboratories surveyed in the phase 1a exercise without any recorded inventory, but have acquired some since the phase 1a survey. A total of 13,484 poliovirus infectious materials were found in the 12 laboratories. Only 8% of the materials were immediately destroyed while the remaining materials (62%) were found in Oyo and Borno states scheduled for destruction within 3-4 months according to WHO protocol for destruction of poliovirus infectious materials. CONCLUSION: This study has revealed the successful containment of all poliovirus infectious materials in the laboratories surveyed. It has also revealed some surveillance gaps. We recommend that the surveillance system be improved to maintain the gains from the containment exercise and avoid reintroduction of infectious materials into biomedical facilities. This reduces the chances of viral reintroduction to the population in general.

Lessons learnt from implementing community engagement interventions in mobile hard-to-reach (HTR) projects in Nigeria, 2014-2015.

BACKGROUND: The year 2014 was a turning point for polio eradication in Nigeria. Confronted with the challenges of increased numbers of polio cases detected in rural, hard-to-reach (HTR), and security-compromised areas of northern Nigeria, the Nigeria polio program introduced the HTR project in four northern states to provide immunization and maternal and child health services in these communities. The project was set up to improve population immunity, increase oral polio vaccine (OPV) and other immunization uptake, and to support Nigeria's efforts to interrupt polio transmission by 2015. Furthermore, the project also aimed to create demand for these services which were often unavailable in the HTR areas. To this end, the program developed a community engagement (CE) strategy to create awareness about the services being provided by the project. The term HTR is operationally defined as geographically difficult terrain, with any of the following criteria: having inter-ward/inter-Local Government Area/interstate borders, scattered households, nomadic population, or waterlogged/riverine area, with no easy to access to healthcare facilities and insecurity. METHODS: We evaluated the outcome of CE activities in Kano, Bauchi, Borno, and Yobe states to examine the methods and processes that helped to increase OPV and third pentavalent (penta3) immunization coverage in areas of implementation. We also assessed the number of community engagers who mobilized caregivers to vaccination posts and the service satisfaction for the performance of the community engagers. RESULTS: Penta3 coverage was at 22% in the first quarter of project implementation and increased to 62% by the fourth quarter of project implementation. OPV coverage also increased from 54% in the first quarter to 76% in the last quarter of the 1-year project implementation. CONCLUSIONS: The systematic implementation of a CE strategy that focused on planning and working with community structures and community engagers in immunization activities assisted in increasing OPV and penta3 immunization coverage.

The global switch from trivalent oral polio vaccine (tOPV) to bivalent oral polio vaccine (bOPV): facts, experiences and lessons learned from the south-south zone; Nigeria, April 2016.

BACKGROUND: The globally synchronized switch from trivalent Oral Polio Vaccine (tOPV) to bivalent Oral Polio Vaccine (bOPV) took place in Nigeria on April 18th 2016. The country is divided into six geopolitical zones. This study reports the experiences and lessons learned from the switch process in the six states that make up Nigeria's south-south geopolitical zone. METHODS: This was a descriptive retrospective review of Nigeria's switch plan and structures used for implementing the tOPV-bOPV switch in the south-south zone. Nigeria's National Polio Emergency Operation Centre (NPEOC) protocols, global guidelines and reports from switch supervisors during the switch were used to provide background information for this study. Quantitative data were derived from reviewing switch monitoring and validation documents as submitted to the NPEOC RESULTS: The switch process took place in all 3078 Health Facilities (HFs) and 123 Local Government Areas (LGAs) that make up the six states in the zone. A total of $139,430 was used for this process. The 'healthcare personnel' component received the highest budgetary allocation (59%) followed by the 'logistics' component (18%). Akwa Ibom state was allocated the highest number of healthcare personnel and hence received the most budgetary allocation compared to the six states (total healthcare personnel = 458, total budgetary allocation = $17,428). Validation of the switch process revealed that eight HFs in Bayelsa, Cross-River, Edo and Rivers states still possessed tOPV in cold-chain while six HFs in Cross-River and Rivers states had tOPV out of cold-chain but without the 'do not use' sticker. Akwa-Ibom was the only state in the zone to have bOPV and Inactivated Polio Vaccine (IPV) available in all its HFs monitored. CONCLUSION: The Nigerian tOPV-bOPV switch was successful. For future Oral Polio Vaccine (OPV) withdrawals, implementation of the switch plan would be more feasible with an earlier dissemination of funds from global donor organizations, which would greatly aid timely planning and preparations. Increased budgetary allocation to the 'logistics' component to accommodate unexpected hikes in transportation prices and the general inefficiencies with power supply in the country is also advised.

Molecular and phenotypic typing of enteropathogenic Escherichia coli isolated in childhood acute diarrhea in Abuja, Nigeria.

INTRODUCTION: Enteropathogenic Escherichia coli (EPEC) causes infectious diarrhea among children in developing countries. However, in Nigeria, due to limited laboratory resources, the genetic diversity of its virulence factors, which includes its intimin subtypes remain undefined. This study aims to evaluate the serotypes, antibiotic resistance and the intimin subtypes genes associated with EPEC strains isolated from children with acute diarrhea in Abuja, Nigeria. METHODOLOGY: EPEC isolates from diarrheic children aged 0-60 months in Abuja, Nigeria were analyzed. PCR for EPEC virulence gene, Hep-2 cell Adherence and serotyping were performed. EPEC strains were further subtyped by PCR reactions for the identification of intimin subtype genes: α (alpha), ß (beta), γ1 (gamma-1), and έ (epsilon). Antibiotic resistance and ESBL production was determined by CLSI guidelines. RESULTS: Overall, 18 (4.5%) out of 400 children with acute diarrhea had EPEC infection. Typical EPEC strains were detected in 14 (3.5%) whereas 4 (1.1%) were atypical EPEC. Fifteen (83.3%) of the EPEC isolated belonged to ß intimin subtype gene, while the remaining 3 EPEC isolates possessed the intimin έ subtype. No α and γ intimin subtypes were detected. Traditional EPEC serotypes O114:H14 were detected only in tEPEC strains. Marked resistant to ß-lactam agents were observed but no ESBL-producing tEPEC or aEPEC was detected. CONCLUSIONS: This is the first report of intimin subtype genes in Abuja, Nigeria. These data will be useful in facilitating the characterization of intimin variants of EPEC and some Shiga toxin-producing E. coli (STEC) in humans and other animal species.

Pattern of the meningococcal meningitis outbreak in Northern Nigeria, 2009.

OBJECTIVES: Despite the availability of vaccines, children are the people most often affected by epidemic meningococcal meningitis. The pattern of the epidemic meningococcal meningitis outbreak in Northern Nigeria in 2009 and the Neisseria meningitidis strains responsible for this epidemic are described here. METHODS: A retrospective cross-sectional study was conducted in 16 states, involving 48 local government areas (LGAs), 91 health facilities, and 96 communities. Data collection involved in-depth interviews with key informants from the federal to the community level, a review of records, and a solution-oriented national workshop with participants from all states of the Federation. Cerebrospinal fluid (CSF) samples were collected from some of the suspected cases at the start of the outbreak and were tested using the rapid Pastorex latex agglutination kit. RESULTS: Kastina (11153, 20.4%), Jigawa (8643, 15.8%), Bauchi (8463, 15.5%), Kano (6811, 12.4%), and Gombe (6110, 11.2%) were the states with the highest prevalence of meningitis. The states of Nasarawa (11.0%), Adamawa (8.0%), and Borno (7.6%) recorded the highest percentage of deaths, while the Shongom (Gombe State 12.5%), Illela (Sokoto State 9.8%), and Ikara (Kaduna State 9.1%) LGAs recorded the most deaths amongst cases seen. CONCLUSIONS: The testing of CSF samples during meningitis outbreaks is recommended in order to monitor the occurrence of the multiple meningitis serotypes during these outbreaks and to direct serotype-specific vaccination response activities.

Diarrheagenic Escherichia coli pathotypes isolated from children with diarrhea in the Federal Capital Territory Abuja, Nigeria.

INTRODUCTION: Escherichia coli are frequently isolated from diarrheic children in the Federal Capital Territory Abuja, Nigeria, but their virulent properties are not routinely evaluated. Therefore, the etiology of childhood diarrheal disease attributable to diarrheagenic Escherichia coli (DEC) in Abuja, Nigeria remains unknown. METHODOLOGY: Stool specimens from 400 acute diarrheic children between 0 and 60 months of age were studied. E. coli strains isolated were evaluated by polymerase chain reaction (PCR) for nine virulence genes and HEp-2 cell adherence to detect and identify five distinct diarrheagenic E. coli categories. RESULTS: Diarrheagenic E.coli was detected in 51 (12.8%) of the diarrheic children. The observed DEC pathotypes were enteropathogenic E. coli (EPEC) in 18 (4.5%) children, enterotoxigenic E. coli (ETEC) in 16 (4.0%), enteroaggrative E. coli (EAEC) in 8 (2.0%), enterohaemorrhagic E. coli (EHEC) in 6 (1.5%), and enteroinvasive E. coli (EIEC) in 3 (0.8%). Four (1.0 %) EPEC strains with only the eae+ gene that adhered diffusely to HEp-2 cell were identified as atypical EPEC. All the DEC categories except atypical EPEC were identified in children between 6 and 12 months of age. CONCLUSIONS: This study underscores the need for routine evaluation of diarrheic children for virulence properties of infectious DEC. Atypical EPEC are emerging among the DEC pathotypes isolated from childhood acute gastroenteritis in Abuja, Nigeria.

Molecular characterization and antibiotic resistance of Salmonella in children with acute gastroenteritis in Abuja, Nigeria.

INTRODUCTION: In Nigeria, acute gastroenteritis in children under five years of age is a major cause of mortality and morbidity; identification and characterization of microbial agents of acute gastroenteritis, including Salmonella, remains a powerful tool for effective management, surveillance, and control. METHODOLOGY: Diarrheal stool samples were directly plated onto differential and selective media to isolate Salmonella. Extended-spectrum beta-lactamases were screened using the double disk diffusion technique and by PCR targeting the blaTEM and blaCTX-M genes. Pulsed-field gel electrophoresis (PFGE) was performed usingthe PulseNet Canada Laboratory protocol for molecular subtyping using the restriction enzymes XbaI and BlnI. RESULTS: The serotypes identified were Salmonella enterica serovar Zanzibar (n = 5), Salmonella Brancaster (n = 3), and one isolate of Salmonella Enteritidis (phage type 1). The following levels of resistance were found among the Salmonella strains: amoxicillin, five strains (55.6%); amoxicillin-clavulanic acid, two strains (22.2%); cephalexin, five strains (55.6%); and cefuroxime, five strains (55.6%). Intermediate resistance was found in five strains (55.6%) only to amoxicillin-clavulanic acid. All isolates were susceptible to nalidixic acid, ciprofloxacin, and ceftriaxone, and no ESBL-producing Salmonella were detected. CONCLUSIONS: Our findings demonstrated the involvement of three Salmonella serovars in acute gastroenteritis; resistance to penicillins and cephalosporins was common.

Surveillance of acute flaccid paralysis in Akwa Ibom State, Nigeria 2004-2009.

INTRODUCTION: The last case of wild polio virus transmission occurred in Akwa Ibom state in October 2001; however, combination high routine immunization coverage with OPV, high quality AFP surveillance, mass immunization campaign in which two doses of potent oral polio vaccine is administered to eligible children and mop-up campaigns in areas with identified immunization or surveillance gaps has help the state in maintaining a free polio status for over ten years. This study was carried out to describe the characteristics of reported acute flaccid paralysis cases between 2004 and 2009, and to evaluate the performance of the acute flaccid paralysis surveillance system using indicators recommended by the World Health Organization. METHODS: A retrospective study was conducted among children, 0-15 years, by the World Health Organization (WHO) and Epidemiology unit of State Ministry of Health (SMOH), Uyo. The demographic characteristics and the results of isolation and identification of polio and other enteroviruses in stool samples sent to the WHO Polio Laboratory Ibadan for cases was analyzed. RESULTS: A total of 521 cases of AFP (270 males and 251 females) aged 0 month to=15 years were reported by the surveillance system between 2004 and 2009. Those below 5 years of age accounted for 82.5% of cases reported and investigated. Of the 521 cases investigated 512 (98.3%) received at least three doses of oral polio vaccine, while 9(1.7) never received any oral polio vaccine (zero-dose). In all 5.1% of the isolates were Sabin, 7.9% non polio enterovirus (NPEV) and 2.3% were classified by national expert committee as compatible with poliomyelitis. There was consistent and steady increase in three critical indicators; Non polio AFP rate in children <15 years from 4.5 to 6.4 per 100,000 population, proportion of AFP cases with 2 stool specimens collected within 14 days of onset of paralysis from 57% in 2005 to 91% in 2009 and proportion of Local Government Areas (Districts) meeting both core indicators from 23% in 2005 to 87% in 2009. The highest numbers of cases were seen in the months of March, May and September. CONCLUSION: This study showed high levels of surveillance performance with some challenges in reverse the cold chain system, the continuation and sustained AFP case detection, prompt investigation and response, improvement in the reserve cold chain system would achieve optimal standards recommended by WHO and might provide a good model for the eradication of poliomyelitis.