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

BACKGROUND: 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. METHODS: 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. FINDINGS: 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). INTERPRETATION: 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. FUNDING: Bill & Melinda Gates Foundation and UK Medical Research Council.

Impact of Supplementary Immunization Activities using Novel Oral Polio Vaccine Type 2 during a Large outbreak of Circulating Vaccine-Derived Poliovirus in Nigeria.

BACKGROUND: Novel oral poliovirus vaccine (OPV) type 2 (nOPV2) has been made available for outbreak response under an emergency use listing authorization based on supportive clinical trial data. Since 2021 more than 350 million doses of nOPV2 were used for control of a large outbreak of circulating vaccine-derived poliovirus type 2 (cVDPV2) in Nigeria. METHODS: Using a bayesian time-series susceptible-infectious-recovered model, we evaluate the field effectiveness of nOPV2 immunization campaigns in Nigeria compared with campaigns using monovalent OPV type 2 (mOPV2). RESULTS: We found that both nOPV2 and mOPV2 campaigns were highly effective in reducing transmission of cVDPV2, on average reducing the susceptible population by 42% (95% confidence interval, 28-54%) and 38% (20-51%) per campaign, respectively, which were indistinguishable from each other in this analysis (relative effect, 1.1 [.7-1.9]). Impact was found to vary across areas and between immunization campaigns. CONCLUSIONS: These results are consistent with the comparable individual immunogenicity of nOPV2 and mOPV2 found in clinical trials but also suggest that outbreak response campaigns may have small impacts in some areas requiring more campaigns than are suggested in current outbreak response procedures.

Update on Wild Poliovirus Type 1 Outbreak - Southeastern Africa, 2021-2022.

Since the Global Polio Eradication Initiative (GPEI) began in 1988, the number of wild poliovirus (WPV) cases has declined by >99.99%. Five of the six World Health Organization (WHO) regions have been certified free of indigenous WPV, and WPV serotypes 2 and 3 have been declared eradicated globally (1). WPV type 1 (WPV1) remains endemic only in Afghanistan and Pakistan (2,3). Before the outbreak described in this report, WPV1 had not been detected in southeastern Africa since the 1990s, and on August 25, 2020, the WHO African Region was certified free of indigenous WPV (4). On February 16, 2022, WPV1 infection was confirmed in one child living in Malawi, with onset of paralysis on November 19, 2021. Genomic sequence analysis of the isolated poliovirus indicated that it originated in Pakistan (5). Cases were subsequently identified in Mozambique. This report summarizes progress in the outbreak response since the initial report (5). During November 2021-December 2022, nine children and adolescents with paralytic polio caused by WPV1 were identified in southeastern Africa: one in Malawi and eight in Mozambique. Malawi, Mozambique, and three neighboring countries at high risk for WPV1 importation (Tanzania, Zambia, and Zimbabwe) responded by increasing surveillance and organizing up to six rounds of national and subnational polio supplementary immunization activities (SIAs).* Although no cases of paralytic WPV1 infection have been reported in Malawi since November 2021 or in Mozambique since August 2022, undetected transmission might be ongoing because of poliovirus surveillance gaps and testing delays. Efforts to further enhance poliovirus surveillance sensitivity, improve SIA quality, and strengthen routine immunization are needed to ensure that WPV1 transmission has been interrupted within 12 months of the first case, thereby preserving the WHO African Region's WPV-free status.

Real-time prediction model of cVDPV2 outbreaks to aid outbreak response vaccination strategies.

BACKGROUND: Circulating vaccine-derived poliovirus outbreaks are spreading more widely than anticipated, which has generated a crisis for the global polio eradication initiative. Effectively responding with vaccination activities requires a rapid risk assessment. This assessment is made difficult by the low case-to-infection ratio of type 2 poliovirus, variable transmissibility, changing population immunity, surveillance delays, and limited vaccine supply from the global stockpile. The geographical extent of responses have been highly variable between countries. METHODS: We develop a statistical spatio-temporal model of short-term, district-level poliovirus spread that incorporates known risk factors, including historical wild poliovirus transmission risk, routine immunization coverage, population immunity, and exposure to the outbreak virus. RESULTS: We find that proximity to recent cVDPV2 cases is the strongest risk factor for spread of an outbreak, and find significant associations between population immunity, historical risk, routine immunization, and environmental surveillance (p < 0.05). We examine the fit of the model to type 2 vaccine derived poliovirus spread since 2016 and find that our model predicts the location of cVDPV2 cases well (AUC = 0.96). We demonstrate use of the model to estimate appropriate scope of outbreak response activities to current outbreaks. CONCLUSION: As type 2 immunity continues to decline following the cessation of tOPV in 2016, outbreak responses to new cVDPV2 detections will need to be faster and larger in scope. We provide a framework that can be used to support decisions on the appropriate size of a vaccination response when new detections are identified. While the model does not account for all relevant local factors that must be considered in the overall vaccination response, it enables a quantitative basis for outbreak response size.

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.

Risk factors for the spread of vaccine-derived type 2 polioviruses after global withdrawal of trivalent oral poliovirus vaccine and the effects of outbreak responses with monovalent vaccine: a retrospective analysis of surveillance data for 51 countries in Africa.

BACKGROUND: Expanding outbreaks of circulating vaccine-derived type 2 poliovirus (cVDPV2) across Africa after the global withdrawal of trivalent oral poliovirus vaccine (OPV) in 2016 are delaying global polio eradication. We aimed to assess the effect of outbreak response campaigns with monovalent type 2 OPV (mOPV2) and the addition of inactivated poliovirus vaccine (IPV) to routine immunisation. METHODS: We used vaccination history data from children under 5 years old with non-polio acute flaccid paralysis from a routine surveillance database (the Polio Information System) and setting-specific OPV immunogenicity data from the literature to estimate OPV-induced and IPV-induced population immunity against type 2 poliomyelitis between Jan 1, 2015, and June 30, 2020, for 51 countries in Africa. We investigated risk factors for reported cVDPV2 poliomyelitis including population immunity, outbreak response activities, and correlates of poliovirus transmission using logistic regression. We used the model to estimate cVDPV2 risk for each 6-month period between Jan 1, 2016, and June 30, 2020, with different numbers of mOPV2 campaigns and compared the timing and location of actual mOPV2 campaigns and the number of mOPV2 campaigns required to reduce cVDPV2 risk to low levels. FINDINGS: Type 2 OPV immunity among children under 5 years declined from a median of 87% (IQR 81-93) in January-June, 2016 to 14% (9-37) in January-June, 2020. Type 2 immunity from IPV among children under 5 years increased from 3% (<1-6%) in January-June, 2016 to 35% (24-47) in January-June, 2020. The probability of cVDPV2 poliomyelitis among children under 5 years was negatively correlated with OPV-induced and IPV-induced immunity and mOPV2 campaigns (adjusted odds ratio: OPV 0·68 [95% CrI 0·60-0·76], IPV 0·82 [0·68-0·99] per 10% absolute increase in estimated population immunity, mOPV2 0·30 [0·20-0·44] per campaign). Vaccination campaigns in response to cVDPV2 outbreaks have been smaller and slower than our model shows would be necessary to reduce risk to low levels, covering only 11% of children under 5 years who are predicted to be at risk within 6 months and only 56% within 12 months. INTERPRETATION: Our findings suggest that as mucosal immunity declines, larger or faster responses with vaccination campaigns using type 2-containing OPV will be required to stop cVDPV2 transmission. IPV-induced immunity also has an important role in reducing the burden of cVDPV2 poliomyelitis in Africa. FUNDING: Bill & Melinda Gates Foundation, Medical Research Council Centre for Global Infectious Disease Analysis, and WHO. TRANSLATION: For the French translation of the abstract see Supplementary Materials section.

A Survey to Assess Serological Prevalence of Poliovirus Antibodies in Areas With High-Risk for Vaccine-Derived Poliovirus Transmission in Chad.

BACKGROUND: World Health Organization African region is wild poliovirus-free; however, outbreaks of vaccine-derived poliovirus type 2 (VDPV2) continue to expand across the continent including in Chad. We conducted a serological survey of polio antibodies in polio high-risk areas of Chad to assess population immunity against poliovirus and estimate the risk of future outbreaks. METHODS: This was a community-based, cross-sectional survey carried out in September 2019. Children between 12 and 59 months were randomly selected using GIS enumeration of structures. Informed consent, demographic and anthropometric data, vaccination history, and blood spots were collected. Seropositivity against all 3 poliovirus serotypes was assessed using a microneutralization assay at Centers for Disease Control and Prevention, Atlanta, GA, USA. RESULTS: Analyzable data were obtained from 236 out of 285 (82.8%) enrolled children. Seroprevalence of polio antibodies for serotypes 1, 2, and 3 was 214/236 (90.7%); 145/236 (61.4%); and 196/236 (86.2%), respectively. For serotype 2, the seroprevalence significantly increased with age (P = .004); chronic malnutrition was a significant risk factor for being type 2-seronegative. INTERPRETATION: Poliovirus type 2 seroprevalence in young children was considered insufficient to protect against the spread of paralytic diseases caused by VDPV2. Indeed, VDPV2 outbreaks were reported from Chad in 2019 and 2020. High-quality immunization response to these outbreaks is needed to prevent further spread.

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

BACKGROUND: The 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. METHODS: Consequently, 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. RESULTS: The 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. CONCLUSION: The 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.

Auto Visual AFP Detection and Response (AVADAR) Improved Polio Surveillance in Lake Chad Polio Outbreak Priority Districts.

The Auto Visual AFP Detection and Response (AVADAR) is a community-based digital platform that deals with the collection and distribution of real-time information. AVADAR makes it possible to report suspected cases of paralysis in the field at the central level. Once a suspected Acute Flaccid Paralysis (AFP) case is detected, a series of reports are sent to the following stakeholders: the nearest training officer, the district focal point, the district AVADAR team, the regional focal point, the central level of the Ministry of Health (MoH) and World Health Organization Country Office (WCO) by SMS and email. The health worker will go to the field to join the community informant who notified the case for a clinical investigation. At the end of this investigation, the health worker via a smartphone will submit an investigation report validating or invalidating the suspected case notified as a true case of AFP or False case. A small server called a gateway is positioned at the central level to ensure the information link between community informants and health workers in each district. A large server is placed in Geneva at Novel-T which allows all countries to connect and view the data in real time. The geolocation of all alerts and investigations of AFP cases is the cornerstone of AVADAR data.

Polio Outbreak Investigation and Response in The Horn of Africa: 2013-2016.

BACKGROUND: There has been civil strife, spanning more than two decades in some countries and recurrent natural disasters in the Horn of Africa (HoA). This has consistently maintained these countries in chronic humanitarian conditions. More important however is the fact that these crises have also denied populations of these countries access to access to lifesaving health services. Children in the difficult terrains and security compromised areas are not given the required immunization services to build their immunity against infectious diseases like the poliovirus. This was the situation in 2013 when the large outbreaks of poliovirus occurred in the HoA. This article reviews the epidemiology, risk, and programme response to what is now famed as the 2013-204 poliovirus outbreaks in the HoA and highlights the challenges that the programme faced in interrupting poliovirus transmission here. METHODS: A case of acute flaccid paralysis (AFP) was defined as a child <15 years of age with sudden onset of fever and paralysis. Polio cases were defined as AFP cases with stool specimens positive for WPV. RESULTS: Between 2013 and 2016, when transmission was interrupted 20,266 polio viruses were in the Horn of Africa region. In response to the outbreak, several supplementary immunization activities were conducted with oral polio vaccine (OPV) The trivalent OPV was used initially, followed subsequently by bivalent OPV, and targeting various age groups, including children aged <5 years, children aged <10 years, and individuals of any age. Other response activities were undertaken to supplement the immunization in controlling the outbreak. Some of these activities included the use of various communication strategies to create awareness, sensitize and mobilize the populations against poliovirus transmission. CONCLUSIONS: The outbreaks were attributed to the existence of clusters of unvaccinated children due to inaccessibility to them by the health system, caused by poor geographical terrain and conflicts. The key lesson therefore is that the existence of populations with low immunity to infections will necessary constitutes breeding grounds for disease outbreak and of course reservoirs to the vectors. Though brought under reasonable control, the outbreaks indicate that the threat of large polio outbreaks resulting from poliovirus importation will remain constant unless polio transmission is interrupted in the remaining polio-endemic countries of the world.

Simulation Exercises To Strengthen Polio Outbreak Preparedness in The Horn of Africa: Experiences and Lessons Learnt.

BACKGROUND: Poliovirus importations and related outbreaks occurred in the Horn of Africa (HoA) following an initial outbreak, which started in Somalia, spread into Kenya within ten days and later into Ethiopia and gradually to other countries in the region. National preparedness plans for responding to poliovirus introduction were insufficient in many countries of the Region. We describe a series of polio outbreak simulation exercises that were implemented to formally test polio outbreak preparedness plans in the HoA countries, as a step to interrupting further transmission. METHODS: The Polio Outbreak Simulation Exercises (POSEs) were designed and implemented. The results were evaluated and recommendations made. The roles of outbreak simulation exercises in maintaining regional polio-free status were assessed. In addition, we performed a comprehensive review of the national plans of all for seven countries in the HoA Region. RESULTS: Seven simulation exercises, delivered between 2016 and 2017 revealed that participating countries were generally prepared for poliovirus introduction, but the level of preparedness needed improvement. The areas in particular need of strengthening were national preparedness plans, initial response, plans for securing vaccine supply, and communications. CONCLUSIONS: Polio outbreak simulation exercises can be valuable tools to help maintain polio-free status and should be extended to other high-risk countries and subnational areas in the HoA Region and elsewhere. There is also need to standardize the process and methods for conducting POSE for comparability.

Strategies to Reach Nomadic Children During Polio SIAs: Experience in Dadaab and Fafi Sub-Counties of Kenya after the 2013-2014 Polio Outbreak.

BACKGROUND: Poliomyelitis, often called polio is a viral paralytic disease caused by Polioviruses. Although all susceptible individuals are at risk of getting infected, only about 1% become paralyzed. During the 2013 Polio Outbreak in Garissa County in Kenya, 50% of the confirmed cases were from the nomadic population although it comprises of only less than 20% of the total population in the county. Following concerns from the Horn of Africa Polio Technical Advisory Group (TAG) regarding inadequate vaccine coverage of nomadic population, several strategies were put in place to improve coverage and Acute Flaccid Paralysis case reporting among nomads in the rest of the planned 2014 polio vaccination campaigns. We describe strategies initiated from April 2014 by the Ministry of Health and partners to reach children in nomadic settlement in the two sub-counties of Dadaab and Fafi of Garissa County. METHODS: The strategies involved improving the mapping and tracking of the nomadic population by establishing lists of nomadic settlements obtained from local clan leaders and government administrators, their <5-year-old populations and focal persons. Focal persons were used to mobilise residents in their respective settlements and guide vaccination teams during campaigns. Settlement leaders were sensitised to report cases of Acute Flaccid Paralysis. In remote hamlets, trained community health volunteers were used as vaccinators. In such places drugs for common illness were also provided during the campaigns. A tracking tool to monitor nomadic population movement and special tally sheets to capture data were created. Training of vaccination personnel and intense social mobilisation activities was done. RESULTS AND CONCLUSION: About 2,000 additional children, from both nomadic and non-nomadic areas were reached when the new initiatives were started. For the first time, an actual number of nomadic children accessed was documented. Suspected AFP cases continued to be reported from nomadic settlements, and the number of zero dose children among the nonpolio AFP cases dropped. With modification and improvement, these strategies may be used to take health services such as routine immunisation to nomadic communities and reduce their vulnerability to vaccine preventable disease outbreaks.

Lessons Learnt from Interregional and Interagency Collaboration in Polio Outbreak Response in the Horn of Africa.

Following the outbreak of poliovirus in the countries in the Horn of Africa, Somalia, Kenya and Ethiopia, in two WHO regions, an outbreak response involving the WHO Africa and WHO East and Mediterranean Regions and partner agencies like the UNICEF in East and Southern African was developed. This paper documents response to polio virus outbreak in the Horn of Africa and the lessons learnt for the interregional and inter-agency collaboration on the response. This collaboration led to speedy interruption of the outbreak and within a period of one year the total virus load of 217 in 2013 was brought down to mere six. This resulted from collaborative planning and implementation of activities to boost the hitherto low immunity in the countries andimprove surveillance among others. A number of lesson were generated from the process. Some of the lessons is critical role such collaboration plays in ensuring simultaneous immunity boosting, information and resources sharing, among other. Some challenges were equally encountered, chiefly in the appropriation of authorities. In conclusion, however, one is safe to note that the collaboration was very fruitful given the timely interruption of transmission.

Real-time monitoring of a circulating vaccine-derived poliovirus outbreak immunization campaign using digital health technologies in South Sudan.

INTRODUCTION: the use of digital health technologies and geographical information systems (GIS) in the conduct of immunization campaigns had proven to be a success story, and is gaining acceptance towards improving supervision, accountability, and real-time access to quality information. The demand for real-time information by policymakers and stakeholders in the polio eradication programme is increasing towards ensuring a world free from all polioviruses. This study aims to develop a tool that monitor and evaluate the circulating vaccine-derived poliovirus (cVDPV) campaign processes in real-time using open data kits (ODK) to collect data, analyze and visualize using an interactive dashboard in Power BI, towards improving timeliness and completeness of data reporting and providing real-time quality information to stakeholders. METHODS: electronic checklists were developed using open data kits (ODK) and uploaded onto android-based smartphones for data collection during a round of cVDPV outbreak response immunization. Supervisors were deployed to the field and the checklists were utilized at both stages of the campaign activities. A Power BI data visualization tool was used for reporting, analysis, and monitoring the activities of the campaign. RESULTS: an interactive dashboard was developed, providing real-time information that supports stakeholders during the campaign processes with improved timeliness and completeness of data reporting. The usage of the tool during the campaign enhanced close supervision, and increased transparency in data availability and accessibility by all partners. CONCLUSION: the study had shown that real-time information has significantly improved the smooth conduct of the immunization campaign processes through identifying gaps, and challenges in the field and can be utilized in similar resource settings including complex and humanitarian. It has demonstrated the capability of mobile phones using ODK for data collection and linked to a Power BI dashboard for enhanced supervision and transparency, and we encourage further studies to assess the effects of the tools on the campaign results.

Effectiveness of the Horn of Africa Polio Outbreak Coordination Office in Nairobi, Kenya.

Background: The WPV1, first detected in Somalia in April 2013, quickly spread to Kenya and Ethiopia and triggered a multi-country coordinated effort. In February 2014, a formal HoA Polio Outbreak Coordination Office was established by WHO AFRO and WHO EMRO in Nairobi to provide technical and managerial leadership. An independent assessment was conducted to ascertain the usefulness of the HoA Coordination in response to the outbreaks. Methods: The independent assessment team conducted desk review of the rules and guidelines forming the HoA Coordination office and committee. It also reviewed minutes of meetings and interviewed various stakeholders at the Regional levels. Results: This independent review of the work of the office, in September 2016, showed that the office was fully functional and had benefited from financial and technical support from regional and global GPEI partners. The office is based in the WHO Kenya Country Office which also provides administrative, logistics and until August 2016, data management support. The close working relationship with technical partners ensured alignment and close coordination of outbreak response activities. The mechanism also allowed partners to identify areas of work based on their expertise and avoided duplication of efforts at the local level. Overall, the office was effective in close monitoring of implementation of the outbreak response, strengthening of cross-border activities, monitoring implementation of the TAG recommendations, improving SIA planning and quality, and expanding independent monitoring in Somalia and South Sudan. Key constraints included limited office space for day-to-day operations, and disruption of some activities due to interruption of contracts of technical staff. However, the closure of the HoA outbreak in August 2015 led to some complacency, resulting in a lost sense of urgency, negatively impacting the coordination. Conclusions: The HoA Coordination Office should continue to function into the foreseeable future. To ensure sustainability of activities, the technical staff should be given contracts for a minimum of 12 months. The Office should reintroduce and schedule the Joint Polio Outbreak Response team meetings at least once every three months.

The epidemiology of chronic kidney disease (CKD) in rural East Africa: A population-based study.

BACKGROUND: Chronic kidney disease (CKD) may be common among individuals living in sub-Saharan Africa due to the confluence of CKD risk factors and genetic predisposition. METHODS: We ascertained the prevalence of CKD and its risk factors among a sample of 3,686 participants of a population-based HIV trial in rural Uganda and Kenya. Prevalent CKD was defined as a serum creatinine-based estimated glomerular filtration rate <60 mL/min/1.73m2 or proteinuria (urine dipstick ≥1+). We used inverse-weighting to estimate the population prevalence of CKD, and multivariable log-link Poisson models to assess the associations of potential risk factors with CKD. RESULTS: The estimated CKD prevalence was 6.8% (95% CI 5.7-8.1%) overall and varied by region, being 12.5% (10.1-15.4%) in eastern Uganda, 3.9% (2.2-6.8%) in southwestern Uganda and 3.7% (2.7-5.1%) in western Kenya. Risk factors associated with greater CKD prevalence included age ≥60 years (adjusted prevalence ratio [aPR] 3.5 [95% CI 1.9-6.5] compared with age 18-29 years), HIV infection (aPR 1.6 [1.1-2.2]), and residence in eastern Uganda (aPR 3.9 [2.6-5.9]). However, two-thirds of individuals with CKD did not have HIV, diabetes, or hypertension as risk factors. Furthermore, we noted many individuals who did not have proteinuria had dipstick positive leukocyturia or hematuria. CONCLUSION: The prevalence of CKD is appreciable in rural East Africa and there are considerable regional differences. Conventional risk factors appear to only explain a minority of cases, and leukocyturia and hematuria were common, highlighting the need for further research into understanding the nature of CKD in sub-Saharan Africa.

HIV Testing and Treatment with the Use of a Community Health Approach in Rural Africa.

BACKGROUND: Universal antiretroviral therapy (ART) with annual population testing and a multidisease, patient-centered strategy could reduce new human immunodeficiency virus (HIV) infections and improve community health. METHODS: We randomly assigned 32 rural communities in Uganda and Kenya to baseline HIV and multidisease testing and national guideline-restricted ART (control group) or to baseline testing plus annual testing, eligibility for universal ART, and patient-centered care (intervention group). The primary end point was the cumulative incidence of HIV infection at 3 years. Secondary end points included viral suppression, death, tuberculosis, hypertension control, and the change in the annual incidence of HIV infection (which was evaluated in the intervention group only). RESULTS: A total of 150,395 persons were included in the analyses. Population-level viral suppression among 15,399 HIV-infected persons was 42% at baseline and was higher in the intervention group than in the control group at 3 years (79% vs. 68%; relative prevalence, 1.15; 95% confidence interval [CI], 1.11 to 1.20). The annual incidence of HIV infection in the intervention group decreased by 32% over 3 years (from 0.43 to 0.31 cases per 100 person-years; relative rate, 0.68; 95% CI, 0.56 to 0.84). However, the 3-year cumulative incidence (704 incident HIV infections) did not differ significantly between the intervention group and the control group (0.77% and 0.81%, respectively; relative risk, 0.95; 95% CI, 0.77 to 1.17). Among HIV-infected persons, the risk of death by year 3 was 3% in the intervention group and 4% in the control group (0.99 vs. 1.29 deaths per 100 person-years; relative risk, 0.77; 95% CI, 0.64 to 0.93). The risk of HIV-associated tuberculosis or death by year 3 among HIV-infected persons was 4% in the intervention group and 5% in the control group (1.19 vs. 1.50 events per 100 person-years; relative risk, 0.79; 95% CI, 0.67 to 0.94). At 3 years, 47% of adults with hypertension in the intervention group and 37% in the control group had hypertension control (relative prevalence, 1.26; 95% CI, 1.15 to 1.39). CONCLUSIONS: Universal HIV treatment did not result in a significantly lower incidence of HIV infection than standard care, probably owing to the availability of comprehensive baseline HIV testing and the rapid expansion of ART eligibility in the control group. (Funded by the National Institutes of Health and others; SEARCH ClinicalTrials.gov number, NCT01864603.).

Inactivated Poliovirus Vaccine Campaign in Kenya: Lessons Learned

Despite being free of polio since 2006 Kenya has suffered a number of wild poliovirus outbreaks in the subsequent years. In December 2013; in response to one such outbreak in Dadaab; inactivated poliovirus vaccine (IPV) was co-administered with oral poliovirus vaccine as a more effective measure in closing immunity gaps. A five-day vaccination campaign was staged followed by a vaccination coverage survey in the refugee camps of Dadaab and the surrounding host communities. A variety of operational challenges were faced - the number of health facilities; outreach sessions; human resources and cold chain logistics were suboptimal in the campaign area with its scattered population and nomadic living pattern. However; despite the challenges; the survey showed that excellent coverage was achieved. Lessons learned evidence that IPV can be administered in similar geographical settings; and that systematically tailored training; timely and capacity-based operational/micro-planning; and evidence-based communication and social mobilization can make for successful outcomes

Community-Based Surveillance on Polio Eradication in the Horn of Africa

Community-based surveillance complements the existing surveillance systems in the mission to control and eradicate polioviruses. It is a cost effective method and has a number of benefits. It was introduced in Ethiopia in 2003 and in the South Sudan CORE Group Polio Project areas in 2010. As well as the results obtained from this initiative; the report looks at the challenges; lessons learned and suggests some ways to strengthen the programme

Cross-Border Initiative on Polio Eradication in the Horn of Africa

Community-based surveillance complements the existing surveillance systems in the mission to control and eradicate polioviruses. It is a cost effective method and has a number of benefits. It was introduced in Ethiopia in 2003 and in the South Sudan CORE Group Polio Project areas in 2010. As well as the results obtained from this initiative; the report looks at the challenges; lessons learned and suggests some ways to strengthen the programme