Spatiotemporal Analysis of Serogroup C Meningococcal Meningitis Spread in Niger and Nigeria and Implications for Epidemic Response.

BACKGROUND: After the re-emergence of serogroup C meningococcal meningitis (MM) in Nigeria and Niger, we aimed to re-evaluate the vaccination policy used to respond to outbreaks of MM in the African meningitis belt by investigating alternative strategies using a lower incidence threshold and information about neighboring districts. METHODS: We used data on suspected and laboratory-confirmed cases in Niger and Nigeria from 2013 to 2017. We calculated global and local Moran's I-statistics to identify spatial clustering of districts with high MM incidence. We used a Pinner model to estimate the impact of vaccination campaigns occurring between 2015 and 2017 and to evaluate the impact of 3 alternative district-level vaccination strategies, compared with that currently used. RESULTS: We found significant clustering of high incidence districts in every year, with local clusters around Tambuwal, Nigeria in 2013 and 2014, Niamey, Niger in 2016, and in Sokoto and Zamfara States in Nigeria in 2017.We estimate that the vaccination campaigns implemented in 2015, 2016, and 2017 prevented 6% of MM cases. Using the current strategy but with high coverage (85%) and timely distribution (4 weeks), these campaigns could have prevented 10% of cases. This strategy required the fewest doses of vaccine to prevent a case. None of the alternative strategies we evaluated were more efficient, but they would have prevented the occurrence of more cases overall. CONCLUSIONS: Although we observed significant spatial clustering in MM in Nigeria and Niger between 2013 and 2017, there is no strong evidence to support a change in methods for epidemic response in terms of lowering the intervention threshold or targeting neighboring districts for reactive vaccination.

Status of the Rollout of the Meningococcal Serogroup A Conjugate Vaccine in African Meningitis Belt Countries in 2018.

BACKGROUND: A novel meningococcal serogroup A conjugate vaccine (MACV [MenAfriVac]) was developed as part of efforts to prevent frequent meningitis outbreaks in the African meningitis belt. The MACV was first used widely and with great success, beginning in December 2010, during initial deployment in Burkina Faso, Mali, and Niger. Since then, MACV rollout has continued in other countries in the meningitis belt through mass preventive campaigns and, more recently, introduction into routine childhood immunization programs associated with extended catch-up vaccinations. METHODS: We reviewed country reports on MACV campaigns and routine immunization data reported to the World Health Organization (WHO) Regional Office for Africa from 2010 to 2018, as well as country plans for MACV introduction into routine immunization programs. RESULTS: By the end of 2018, 304 894 726 persons in 22 of 26 meningitis belt countries had received MACV through mass preventive campaigns targeting individuals aged 1-29 years. Eight of these countries have introduced MACV into their national routine immunization programs, including 7 with catch-up vaccinations for birth cohorts born after the initial rollout. The Central African Republic introduced MACV into its routine immunization program immediately after the mass 1- to 29-year-old vaccinations in 2017 so no catch-up was needed. CONCLUSIONS: From 2010 to 2018, successful rollout of MACV has been recorded in 22 countries through mass preventive campaigns followed by introduction into routine immunization programs in 8 of these countries. Efforts continue to complete MACV introduction in the remaining meningitis belt countries to ensure long-term herd protection.

Evidence-informed vaccination decision-making in countries: Progress, challenges and opportunities.

Countries face an increasingly complex vaccination landscape. As well as ever-changing infectious disease epidemiology, the number and diversity of vaccine-preventable diseases, vaccine products, and vaccine technologies continue to increase. To ensure that vaccination decision-making is transparent, country-owned and informed by sound scientific evidence, many countries have established national immunization technical advisory groups (NITAGs) to provide independent expert advice. The past decade has seen substantial growth in NITAG numbers and functionality, and there is now a need to consolidate this progress, by further capacity building, to ensure that NITAGs are responsive to the changing face of immunization over the next decade.

Overlapping topics in advisory reports issued by five well-established European National Immunization Technical Advisory Groups from 2011 to 2014.

National Immunization Technical Advisory Groups (NITAGs) are facing increasingly complex vaccination issues together with a lack of human resources for evidence assessment and data analysis. One way to reduce these burdens could be to share some of the preparatory work across NITAGs. We conducted an inventory of all the advisory reports issued by five well-established European NITAGs from 2011 to 2014 to assess overlaps in issues and activities. A total of 104 advisory reports were retrieved. Advisory reports on the same issues were compared to identify overlapping activities and processes. Advisory reports issued by the five NITAGs showed little overlap in issues and processes. A first step towards efficient collaboration would be to establish an independent platform to provide insight into each NITAG's work and to facilitate the exchange of agendas, assessment frameworks and evidence.

Supporting countries in establishing and strengthening NITAGs: lessons learned from 5 years of the SIVAC initiative.

To empower governments to formulate rational policies without pressure from any group, and to increase the use of evidence-based decision-making to adapt global recommendations on immunization to their local context, the WHO has recommended on multiple occasions that countries should establish National Immunization Technical Advisory Groups (NITAGs). The World Health Assembly (WHA) reinforced those recommendations in 2012 when Member States endorsed the Decade of Vaccines Global Vaccine Action Plan (GVAP). NITAGs are multidisciplinary groups of national experts responsible for providing independent, evidence-informed advice to health authorities on all policy-related issues for all vaccines across all populations. In 2012, according to the WHO-UNICEF Joint Reporting Form, among 57 countries eligible for immunization program financial support from the GAVI Alliance, only 9 reported having a functional NITAG. Since 2008, the Supporting Independent Immunization and Vaccine Advisory Committees (SIVAC) Initiative (at the Agence de Médecine Préventive or AMP) in close collaboration with the WHO and other partners has been working to accelerate and systematize the establishment of NITAGs in low- and middle-income countries. In addition to providing direct support to countries to establish advisory groups, the initiative also supports existing NITAGs to strengthen their capacity in the use of evidence-based processes for decision-making aligned with international standards. After 5 years of implementation and based on lessons learned, we recommend that future efforts should target both expanding new NITAGs and strengthening existing NITAGs in individual countries, along three strategic lines: (i) reinforce NITAG institutional integration to promote sustainability and credibility, (ii) build technical capacity within NITAG secretariats and evaluate NITAG performance, and (iii) increase networking and regional collaborations. These should be done through the development and dissemination of tools and guidelines, and information through a variety of adapted mechanisms.