Meningococcal ACWYX Conjugate Vaccine in 2-to-29-Year-Olds in Mali and Gambia.

BACKGROUND: An effective, affordable, multivalent meningococcal conjugate vaccine is needed to prevent epidemic meningitis in the African meningitis belt. Data on the safety and immunogenicity of NmCV-5, a pentavalent vaccine targeting the A, C, W, Y, and X serogroups, have been limited. METHODS: We conducted a phase 3, noninferiority trial involving healthy 2-to-29-year-olds in Mali and Gambia. Participants were randomly assigned in a 2:1 ratio to receive a single intramuscular dose of NmCV-5 or the quadrivalent vaccine MenACWY-D. Immunogenicity was assessed at day 28. The noninferiority of NmCV-5 to MenACWY-D was assessed on the basis of the difference in the percentage of participants with a seroresponse (defined as prespecified changes in titer; margin, lower limit of the 96% confidence interval [CI] above -10 percentage points) or geometric mean titer (GMT) ratios (margin, lower limit of the 98.98% CI >0.5). Serogroup X responses in the NmCV-5 group were compared with the lowest response among the MenACWY-D serogroups. Safety was also assessed. RESULTS: A total of 1800 participants received NmCV-5 or MenACWY-D. In the NmCV-5 group, the percentage of participants with a seroresponse ranged from 70.5% (95% CI, 67.8 to 73.2) for serogroup A to 98.5% (95% CI, 97.6 to 99.2) for serogroup W; the percentage with a serogroup X response was 97.2% (95% CI, 96.0 to 98.1). The overall difference between the two vaccines in seroresponse for the four shared serogroups ranged from 1.2 percentage points (96% CI, -0.3 to 3.1) for serogroup W to 20.5 percentage points (96% CI, 15.4 to 25.6) for serogroup A. The overall GMT ratios for the four shared serogroups ranged from 1.7 (98.98% CI, 1.5 to 1.9) for serogroup A to 2.8 (98.98% CI, 2.3 to 3.5) for serogroup C. The serogroup X component of the NmCV-5 vaccine generated seroresponses and GMTs that met the prespecified noninferiority criteria. The incidence of systemic adverse events was similar in the two groups (11.1% in the NmCV-5 group and 9.2% in the MenACWY-D group). CONCLUSIONS: For all four serotypes in common with the MenACWY-D vaccine, the NmCV-5 vaccine elicited immune responses that were noninferior to those elicited by the MenACWY-D vaccine. NmCV-5 also elicited immune responses to serogroup X. No safety concerns were evident. (Funded by the U.K. Foreign, Commonwealth, and Development Office and others; ClinicalTrials.gov number, NCT03964012.).

Meningococcal Serogroup ACWYX Conjugate Vaccine in Malian Toddlers.

BACKGROUND: Neisseria meningitidis serogroups A, B, C, W, X, and Y cause outbreaks of meningococcal disease. Quadrivalent conjugate vaccines targeting the A, C, W, and Y serogroups are available. A pentavalent vaccine that also includes serogroup X (NmCV-5) is under development. METHODS: We conducted a phase 2, observer-blinded, randomized, controlled trial involving Malian children 12 to 16 months of age. Participants were assigned in a 2:2:1 ratio to receive nonadjuvanted NmCV-5, alum-adjuvanted NmCV-5, or the quadrivalent vaccine MenACWY-D, administered intramuscularly in two doses 12 weeks apart. Participants were followed for safety for 169 days. Immunogenicity was assessed with an assay for serum bactericidal antibody (SBA) with rabbit complement on days 0, 28, 84, and 112. RESULTS: A total of 376 participants underwent randomization, with 150 assigned to each NmCV-5 group and 76 to the MenACWY-D group; 362 participants received both doses of vaccine. A total of 1% of the participants in the nonadjuvanted NmCV-5 group, 1% of those in the adjuvanted NmCV-5 group, and 4% of those in the MenACWY-D group reported local solicited adverse events; 6%, 5%, and 7% of the participants, respectively, reported systemic solicited adverse events. An SBA titer of at least 128 was seen in 91 to 100% (for all five serotypes) of the participants in the NmCV-5 groups and in 36 to 99% (excluding serogroup X) of those in the MenACWY-D group at day 84 (before the second dose); the same threshold was met in 99 to 100% (for all five serotypes) of the participants in the NmCV-5 groups and in 92 to 100% (excluding serogroup X) of those in the MenACWY-D group at day 112. Immune responses to the nonadjuvanted and adjuvanted NmCV-5 formulations were similar. CONCLUSIONS: No safety concerns were identified with two doses of NmCV-5. A single dose of NmCV-5 elicited immune responses that were similar to those observed with two doses of MenACWY-D. Adjuvanted NmCV-5 provided no discernible benefit over nonadjuvanted NmCV-5. (Funded by the U.K. Foreign, Commonwealth, and Development Office; ClinicalTrials.gov number, NCT03295318.).

Strengthening local capacity for abortion-related research in contexts with highly restrictive abortion laws: The case of STARS in Mali.

Strong local abortion research capacity is missing in many African countries. We report on the Strengthening Abortion Research Capacity in sub-Saharan Africa (STARS) program, an ongoing initiative to strengthen local capacity for abortion research in Mali, West Africa. We highlight the background, context, and methodology of the initiative as well as its achievements, challenges, and emerging lessons. Within a short time, STARS has initiated some key studies on abortion in Mali and created a much-needed platform for nurturing the country's next generation of abortion researchers, institutionalizing abortion research, increasing the quantity and quality of locally generated evidence on abortion, and facilitating evidence-informed abortion policy and programmatic action. The program's learning-by-doing approach has boosted the skills of individual researchers while also enhancing institution-based abortion and sexual and reproductive health and rights (SRHR) research expertise in Mali. Although STARS' capacity to deliver its mandate over time is evident, ultimate results will depend on the sustained commitment of funders to the program in the full realization that capacity building requires long-term investment and support for it to fully bear fruits.

Provision and uptake of sexual and reproductive health services during the COVID-19 pandemic: The case of Mali.

A qualitative study assessed the effects of the COVID-19 epidemic on Malian sexual and reproductive health services. Sexual and reproductive health (SRHR) providers in 25 purposively selected public health facilities in urban Bamako, rural Kita (western Mali) and Koutiala (southeast Mali) were interviewed. Disruptions within SRH supply, staffing, the prioritization of SRHR services, and patients' ability to seek, obtain and pay for services were reported across urban and rural settings at all levels of public health care, and by all cadres of SRHR providers. Most facilities in the study areas sustained some SRHR services at the height of the COVID-19 epidemic through innovative outreach and phone-based consultations. This study offers critical lessons for SRHR service provision during future waves of the pandemic or during periods of comparable emergency.

Respiratory Syncytial Virus (RSV) Neutralizing Antibodies at Birth Predict Protection from RSV Illness in Infants in the First 3 Months of Life.

BACKGROUND: Respiratory syncytial virus (RSV) is a leading cause of viral pneumonia and bronchiolitis during the first 6 months of life. Placentally transferred antibodies can prevent severe RSV illness, and maternal immunization may reduce illness in young infants. Identification of protective antibody levels facilitates the advancement of vaccine candidates and maternal immunization. METHODS: We conducted a nested case-control study with 587 Malian mother-infant pairs, followed from birth to age 6 months. RSV cases were infants who developed influenza-like illness (ILI) or pneumonia and were RSV-positive by polymerase chain reaction. Cases were matched to healthy controls and RSV-negative ILI controls. RSV-A and RSV-B neutralizing antibodies were measured in maternal, cord blood, and infant sera at age 3 and 6 months. RESULTS: Maternal antibodies were efficiently transferred to infants. Maternal and infant RSV titers were strongly correlated. Infant antibody titers against RSV-A were 3 times higher than those against RSV-B. At birth, infants who remained healthy had significantly higher RSV-A and RSV-B titers compared with infants who subsequently contracted RSV. RSV-A inhibitory concentration (IC)80 titer >239 or RSV-B titer >60 at birth was significantly associated with being a healthy control compared with an RSV case within the first 3 months of life. RSV-A IC80 titers in cord blood were associated with decreased episodes of pneumonia. CONCLUSIONS: Maternally acquired RSV antibodies were associated with protection of infants against community-detected cases of RSV-ILI and pneumonia. RSV titers in cord blood can predict whether an infant will be infected with RSV or remain uninfected.

Epidemiology, Risk Factors, and Outcomes of Respiratory Syncytial Virus Infections in Newborns in Bamako, Mali.

BACKGROUND: Few studies describe the respiratory syncytial virus (RSV) burden in African populations, and most have utilized hospital-based surveillance. In Mali, no community-based studies exist of the incidence or epidemiology of RSV infection. This study provides the first estimates of RSV incidence in Mali. METHODS: In a cohort of infants enrolled in a clinical trial of maternal influenza vaccination, we estimate incidence of RSV-associated febrile illness in the first 6 months of life and identify risk factors for RSV infection and progression to severe disease. Infants (N = 1871) were followed from birth to 6 months of age and visited weekly to detect pneumonia and influenza-like illness. Baseline covariates were explored as risk factors for RSV febrile illness and RSV pneumonia or hospitalization. RESULTS: Incidence of RSV illness was estimated at 536.8 per 1000 person-years, and 86% (131/153) of RSV illness episodes were positive for RSV-B. RSV illness was most frequent in the fifth month of life and associated with having older mothers and with lower parity. The incidence of RSV-associated hospitalizations was 45.6 per 1000 person-years. Among infants with RSV illness, males were more likely to be hospitalized. The incidence of RSV pneumonia was 29 cases per 1000 person-years. CONCLUSIONS: In the first 6 months of life, Malian infants have a high incidence of RSV illness, primarily caused by RSV-B. Prevention of early RSV will require passive protection via maternal immunization in pregnancy. Mali is the first country where RSV-B has been identified as the dominant subtype, with potential implications for vaccine development.

Evaluation of a Booster Dose of Pentavalent Rotavirus Vaccine Coadministered With Measles, Yellow Fever, and Meningitis A Vaccines in 9-Month-Old Malian Infants.

Background: Rotavirus vaccines given to infants are safe and efficacious. A booster dose of rotavirus vaccine could extend protection into the second year of life in low-resource countries. Methods: We conducted an open-label, individual-randomized trial in Bamako, Mali. We assigned 600 infants aged 9-11 months to receive measles vaccine (MV), yellow fever vaccine (YFV), and meningococcal A conjugate vaccine (MenAV) with or without pentavalent rotavirus vaccine (PRV). We assessed the noninferiority (defined as a difference of ≤10%) of seroconversion and seroresponse rates to MV, YFV, and MenAV. We compared the seroresponse to PRV. Results: Seroconversion to MV occurred in 255 of 261 PRV recipients (97.7%) and 246 of 252 control infants (97.6%; difference, 0.1% [95% confidence interval {CI}, -4.0%-4.2%]). Seroresponse to YFV occurred in 48.1% of PRV recipients (141 of 293), compared with 52.2% of controls (153 of 293; difference, -4.1% [95% CI, -12.2%-4.0%]). A 4-fold rise in meningococcus A bactericidal titer was observed in 273 of 292 PRV recipients (93.5%) and 276 of 293 controls (94.2%; difference, -0.7% [95% CI, -5.2%-3.8%]). Rises in geometric mean concentrations of immunoglobulin A and immunoglobulin G antibodies to rotavirus were higher among PRV recipients (118 [95% CI, 91-154] and 364 [95% CI, 294-450], respectively), compared with controls (68 [95% CI, 50-92] and 153 [95% CI, 114-207], respectively). Conclusions: PRV did not interfere with MV and MenAV; this study could not rule out interference with YFV. PRV increased serum rotavirus antibody levels. Clinical Trials Registration: NCT02286895.

Community Perspectives Associated With the African PsA-TT (MenAfriVac) Vaccine Trials.

BACKGROUND: The Meningitis Vaccine Project (MVP) was established to address epidemic meningitis as a public health problem in sub-Saharan Africa and, to that end, worked to develop a group A meningococcal conjugate vaccine, PsA-TT. METHODS: Experiences in 4 clinical trial sites are described. Culturally sensitive collaborative strategies were adopted to manage acceptable communication methods, peculiarities with the consent process, participant medical issues, community care, and death. RESULTS: The clinical trials were completed successfully through community acceptance and active community collaboration. The trials also strengthened the capacities in the participating communities, and actively worked to resolve community problems. CONCLUSIONS: The understanding and integration of sociocultural realities of communities were major assets in the conduct and acceptance of these trials. MVP succeeded in these sites and provided a sound example for future clinical studies in Africa. CLINICAL TRIALS REGISTRATION: ISRTCN78147026 (PsA-TT 002); ISRCTN87739946 (PsA-TT 003); ISRCTN82484612 (PsA-TT 004); PACTR ATMR2010030001913177 (PsA-TT 006); and PACTR201110000328305 (PsA-TT 007).

A Phase 3, Double-Blind, Randomized, Active Controlled Study to Evaluate the Safety of MenAfriVac in Healthy Malians.

BACKGROUND: A safe, affordable, and highly immunogenic meningococcal A conjugate vaccine (PsA-TT, MenAfriVac) was developed to control epidemic group A meningitis in Africa. Documentation of the safety specifications of the PsA-TT vaccine was warranted, with sufficient exposure to detect potential rare vaccine-related adverse reactions. METHODS: This phase 3, double-blind, randomized, active controlled clinical study was designed to evaluate the safety--primarily vaccine-related serious adverse events (SAEs)--up to 3 months after administration of a single dose of the PsA-TT vaccine to subjects aged 1-29 years in Mali. Safety outcomes were also compared to those following a single dose of a licensed meningococcal ACWY polysaccharide vaccine (PsACWY). RESULTS: No vaccine-related SAEs occurred during the 3 months of follow-up of 4004 subjects vaccinated with a single dose of PsA-TT. When compared to PsACWY (1996 subjects), tenderness at the injection site appeared to be more frequent in the PsA-TT group. However, rates of local induration, systemic reactions, adverse events (AEs), and SAEs were similar in both groups, and unsolicited AEs and SAEs were all unrelated to the study vaccines. CONCLUSIONS: The study confirmed on a large scale the excellent safety profile of a single dose of PsA-TT when administered to its entire target population of 1-29 years of age. CLINICAL TRIALS REGISTRATION: PACTR ATMR201003000191317.

Ethical Challenges and Lessons Learned During the Clinical Development of a Group A Meningococcal Conjugate Vaccine.

BACKGROUND: The group A meningococcal vaccine (PsA-TT) clinical development plan included clinical trials in India and in the West African region between 2005 and 2013. During this period, the Meningitis Vaccine Project (MVP) accumulated substantial experience in the ethical conduct of research to the highest standards. METHODS: Because of the public-private nature of the sponsorship of these trials and the extensive international collaboration with partners from a diverse setting of countries, the ethical review process was complex and required strategic, timely, and attentive communication to ensure the smooth review and approval for the clinical studies. Investigators and their site teams fostered strong community relationships prior to, during, and after the studies to ensure the involvement and the ownership of the research by the participating populations. As the clinical work proceeded, investigators and sponsors responded to specific questions of informed consent, pregnancy testing, healthcare, disease prevention, and posttrial access. RESULTS: Key factors that led to success included (1) constant dialogue between partners to explore and answer all ethical questions; (2) alertness and preparedness for emerging ethical questions during the research and in the context of evolving international ethics standards; and (3) care to assure that approaches were acceptable in the diverse community contexts. CONCLUSIONS: Many of the ethical issues encountered during the PsA-TT clinical development are familiar to groups conducting field trials in different cultural settings. The successful approaches used by the MVP clinical team offer useful examples of how these problems were resolved. CLINICAL TRIALS REGISTRATION: ISRCTN17662153 (PsA-TT-001); ISRTCN78147026 (PsA-TT-002); ISRCTN87739946 (PsA-TT-003); ISRCTN46335400 (PsA-TT-003a); ISRCTN82484612 (PsA-TT-004); CTRI/2009/091/000368 (PsA-TT-005); PACTR ATMR2010030001913177 (PsA-TT-006); PACTR201110000328305 (PsA-TT-007).

Antibody Persistence 1-5 Years Following Vaccination With MenAfriVac in African Children Vaccinated at 12-23 Months of Age.

BACKGROUND: Following mass vaccination campaigns in the African meningitis belt with group A meningococcal conjugate vaccine, MenAfriVac (PsA-TT), disease due to group A meningococci has nearly disappeared. Antibody persistence in healthy African toddlers was investigated. METHODS: African children vaccinated at 12-23 months of age with PsA-TT were followed for evaluation of antibody persistence up to 5 years after primary vaccination. Antibody persistence was evaluated by measuring group A serum bactericidal antibody (SBA) with rabbit complement and by a group A-specific IgG enzyme-linked immunosorbent assay (ELISA). RESULTS: Group A antibodies measured by SBA and ELISA were shown to decline in the year following vaccination and plateaued at levels significantly above baseline for up to 5 years following primary vaccination. CONCLUSIONS: A single dose of PsA-TT induces long-term sustained levels of group A meningococcal antibodies for up to 5 years after vaccination. CLINICAL TRIALS REGISTRATION: ISRTCN78147026.

Antibody Persistence at 1 and 4 Years Following a Single Dose of MenAfriVac or Quadrivalent Polysaccharide Vaccine in Healthy Subjects Aged 2-29 Years.

BACKGROUND: Mass vaccination campaigns of the population aged 1-29 years with 1 dose of group A meningococcal (MenA) conjugate vaccine (PsA-TT, MenAfriVac) in African meningitis belt countries has resulted in the near-disappearance of MenA. The vaccine was tested in clinical trials in Africa and in India and found to be safe and highly immunogenic compared with the group A component of the licensed quadrivalent polysaccharide vaccine (PsACWY). Antibody persistence in Africa and in India was investigated. METHODS: A total of 900 subjects aged 2-29 years were followed up for 4 years in Senegal, Mali, and The Gambia (study A). A total of 340 subjects aged 2-10 years were followed up for 1 year in India (study B). In study A, subjects were randomized in a 2:1 ratio, and in study B a 1:1 ratio to receive either PsA-TT or PsACWY. Immunogenicity was evaluated by measuring MenA serum bactericidal antibody (SBA) with rabbit complement and by a group A-specific immunoglobulin G (IgG) enzyme-linked immunosorbent assay. RESULTS: In both studies, substantial SBA decay was observed at 6 months postvaccination in both vaccine groups, although more marked in the PsACWY group. At 1 year and 4 years (only for study A) postvaccination, SBA titers were relatively sustained in the PsA-TT group, whereas a slight increasing trend, more pronounced among the youngest, was observed in the participants aged <18 years in the PsACWY groups. The SBA titers were significantly higher in the PsA-TT group than in the PsACWY group at any time point, and the majority of subjects in the PsA-TT group had SBA titers ≥128 and group A-specific IgG concentrations ≥2 µg/mL at any point in time in both the African and Indian study populations. CONCLUSIONS: Four years after vaccination with a single dose of PsA-TT vaccine in Africa, most subjects are considered protected from MenA disease. CLINICAL TRIALS REGISTRATION: PsA-TT-003 (ISRCTN87739946); PsA-TT-003a (ISRCTN46335400).

Immunogenicity and safety of a meningococcal A conjugate vaccine in Africans.

BACKGROUND: Group A meningococci are the source of major epidemics of meningitis in Africa. An affordable, highly immunogenic meningococcal A conjugate vaccine is needed. METHODS: We conducted two studies in Africa to evaluate a new MenA conjugate vaccine (PsA-TT). In study A, 601 children, 12 to 23 months of age, were randomly assigned to receive PsA-TT, a quadrivalent polysaccharide reference vaccine (PsACWY), or a control vaccine (Haemophilus influenzae type b conjugate vaccine [Hib-TT]). Ten months later, these children underwent another round of randomization within each group to receive a full dose of PsA-TT, a one-fifth dose of PsACWY, or a full dose of Hib-TT, with 589 of the original participants receiving a booster dose. In study B, 900 subjects between 2 and 29 years of age were randomly assigned to receive PsA-TT or PsACWY. Safety and reactogenicity were evaluated, and immunogenicity was assessed by measuring the activity of group A serum bactericidal antibody (SBA) with rabbit complement and performing an IgG group A-specific enzyme-linked immunosorbent assay. RESULTS: In study A, 96.0% of the subjects in the PsA-TT group and 63.7% of those in the PsACWY group had SBA titers that were at least four times as high as those at baseline; in study B, 78.2% of the subjects in the PsA-TT group and 46.2% of those in the PsACWY group had SBA titers that were at least four times as high as those at baseline. The geometric mean SBA titers in the PsA-TT groups in studies A and B were greater by factors of 16 and 3, respectively, than they were in the PsACWY groups (P<0.001). In study A, the PsA-TT group had higher antibody titers at week 40 than the PsACWY group and had obvious immunologic memory after receiving a polysaccharide booster vaccine. Safety profiles were similar across vaccine groups, although PsA-TT recipients were more likely than PsACWY recipients to have tenderness and induration at the vaccination site. Adverse events were consistent with age-specific morbidity in the study areas; no serious vaccine-related adverse events were reported. CONCLUSIONS: The PsA-TT vaccine elicited a stronger response to group A antibody than the PsACWY vaccine. (Funded by the Meningitis Vaccine Project through a grant from the Bill and Melinda Gates Foundation; Controlled-Trials.com numbers, ISRCTN78147026 and ISRCTN87739946.).

Safety and immunogenicity of a single dose of Tdap compared to Td in pregnant women in Mali and 3 its effect on infant immune responses: a single-centre, randomised, double-blind, active-controlled phase 2 study.

Background: While maternal pertussis vaccination is a strategy to reduce infant morbidity, safety and immunogenicity data are limited in sub-Saharan Africa. We aimed to evaluate the safety of a single dose of tetanus, diphtheria and acellular pertussis vaccine (Tdap) vaccine compared to tetanus and diphtheria vaccine (Td) vaccine in pregnant women in Bamako, Mali and to assess the pertussis toxin (PT) antibody response at birth. Methods: In this phase 2, single-centre, randomised, double-blind, active-controlled study, from 23 January 2019 to 10 July 2019, healthy 18-39 year old women in the second trimester of a singleton pregnancy were randomised 2:1 to receive Tdap or Td. Blood was tested for serum immunoglobulin G (IgG) against PT and other vaccine antigens using a qualified Meso Scale Discovery multiplex immunoassay. The co-primary objectives evaluated safety and birth anti-PT levels. Infant immune responses to whole-cell pertussis vaccine (DTwP) were assessed. Statistical analysis was descriptive. This trial is registered with clinicaltrials.gov, NCT03589768. Findings: 133 women received Tdap and 67 received Td, with 126 and 66 livebirths, respectively. In the Tdap group, 22 serious adverse events (SAEs) including one maternal death occurred in 20 participants (15·0%), with 10 SAEs in 10 participants (14·9%) in the Td group. Among infants, 18 events occurred among 13 participants (10.3%) and 8 SAEs in 6 participants (9.1%), including three and two infant deaths, occurred in Tdap and Td groups, respectively. None were related to study vaccines. Anti-PT geometric mean concentration (GMC) at birth in the Tdap group was higher than in the Td group (55.4 [46.2-66.6] IU/ml vs 7.9 [5.4-11.5] IU/ml). One month after the third dose of DTwP, the GMC in infants born to mothers in the Tdap group were lower compared to the Td group (20.2 [13.7-29.9] IU/ml vs 77.2 [32.2-184.8] IU/ml). By 6 months of age, the anti- PT GMCs were 17.3 [12.8-23.4] IU/ml and 67.1 [35.5-126.7] IU/ml in Tdap and Td groups, respectively. At birth, anti-tetanus toxin (TT) GMCs were higher in infants in the Td vs Tdap group (5.9 [5.0-7.0] IU/ml vs 4.1 [3.5-4.8] IU/ml). Anti-diphtheria toxin GMCs were similar in both groups. Interpretation: Tdap administered to pregnant women in Mali is safe and well-tolerated. Infants of mothers who received Tdap were born with high PT and protective anti-TT antibody levels. By six months of age, after primary vaccination, the PT levels were lower in the Tdap group compared to the Td group. The blunted immune responses to primary DTwP vaccination in the Tdap infant group warrant further study. Funding: This project was funded by National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), under contract numbers 75N93021C00012 (The Emmes Company), and HHSN27220130000221 (University of Maryland, Baltimore). Dr. Susana Portillo was supported by NIH award no. T32AI007524. NIAID, NIH provided Tdap vaccine (BOOSTRIX).

An Upsurge of Measles Cases in Mali-a Consequence of Pandemic-associated Disruption in Routine Immunization.

Measles deaths highlight immunization program gaps. In the Child Health and Mortality Prevention Surveillance study in Mali, we observed a rise in under-5 measles-related deaths in 2022 that corresponded with increased measles cases at the same time and a decline in measles vaccine coverage in Mali in 2020.

The Enterics for Global Health (EFGH) Shigella Surveillance Study in Mali.

Background: In 2002, the Centre pour le Développement des Vaccins du Mali (CVD-Mali) was established as a partnership between the Mali Ministry of Health and the University of Maryland, Baltimore. Since its creation, CVD-Mali has been dedicated to describing the epidemiology of infectious diseases, supporting the development of vaccines, and training a team of local researchers. CVD-Mali participated in the Global Enteric Multicenter Study from 2007 to 2010 and the Vaccine Impact on Diarrhea in Africa study from 2015 to 2018, where the importance of Shigella as an enteric pathogen was established. Methods: In the Enterics for Global Health (EFGH) Shigella surveillance study, CVD-Mali will conduct Shigella surveillance at 4 health centers serving the population currently participating in a demographic surveillance system and will measure the local incidence of Shigella diarrhea and related outcomes in 6- to 35-month-old children. Antibiotic sensitivity patterns and the costs related to these cases will also be measured. Results: We anticipate reporting the number of diarrhea episodes that are positive by stool culture, the antibiotic susceptibility of these isolates, and the management and outcomes of these cases. Conclusions: In Mali, the EFGH study will contribute valuable information to understanding the burden of Shigella in this population. These data will inform the evaluation of vaccine candidates.

Diarrhea Case Surveillance in the Enterics for Global Health Shigella Surveillance Study: Epidemiologic Methods.

Background: Shigella is a leading cause of acute watery diarrhea, dysentery, and diarrhea-attributed linear growth faltering, a precursor to stunting and lifelong morbidity. Several promising Shigella vaccines are in development and field efficacy trials will require a consortium of potential vaccine trial sites with up-to-date Shigella diarrhea incidence data. Methods: The Enterics for Global Health (EFGH) Shigella surveillance study will employ facility-based enrollment of diarrhea cases aged 6-35 months with 3 months of follow-up to establish incidence rates and document clinical, anthropometric, and financial consequences of Shigella diarrhea at 7 country sites (Mali, Kenya, The Gambia, Malawi, Bangladesh, Pakistan, and Peru). Over a 24-month period between 2022 and 2024, the EFGH study aims to enroll 9800 children (1400 per country site) between 6 and 35 months of age who present to local health facilities with diarrhea. Shigella species (spp.) will be identified and serotyped from rectal swabs by conventional microbiologic methods and quantitative polymerase chain reaction. Shigella spp. isolates will undergo serotyping and antimicrobial susceptibility testing. Incorporating population and healthcare utilization estimates from contemporaneous household sampling in the catchment areas of enrollment facilities, we will estimate Shigella diarrhea incidence rates. Conclusions: This multicountry surveillance network will provide key incidence data needed to design Shigella vaccine trials and strengthen readiness for potential trial implementation. Data collected in EFGH will inform policy makers about the relative importance of this vaccine-preventable disease, accelerating the time to vaccine availability and uptake among children in high-burden settings.

Quantifying the Cost of Shigella Diarrhea in the Enterics for Global Health (EFGH) Shigella Surveillance Study.

Background: Comparative costs of public health interventions provide valuable data for decision making. However, the availability of comprehensive and context-specific costs is often limited. The Enterics for Global Health (EFGH) Shigella surveillance study-a facility-based diarrhea surveillance study across 7 countries-aims to generate evidence on health system and household costs associated with medically attended Shigella diarrhea in children. Methods: EFGH working groups comprising representatives from each country (Bangladesh, Kenya, Malawi, Mali, Pakistan, Peru, and The Gambia) developed the study methods. Over a 24-month surveillance period, facility-based surveys will collect data on resource use for the medical treatment of an estimated 9800 children aged 6-35 months with diarrhea. Through these surveys, we will describe and quantify medical resources used in the treatment of diarrhea (eg, medication, supplies, and provider salaries), nonmedical resources (eg, travel costs to the facility), and the amount of caregiver time lost from work to care for their sick child. To assign costs to each identified resource, we will use a combination of caregiver interviews, national medical price lists, and databases from the World Health Organization and the International Labor Organization. Our primary outcome will be the estimated cost per inpatient and outpatient episode of medically attended Shigella diarrhea treatment across countries, levels of care, and illness severity. We will conduct sensitivity and scenario analysis to determine how unit costs vary across scenarios. Conclusions: Results from this study will contribute to the existing body of literature on diarrhea costing and inform future policy decisions related to investments in preventive strategies for Shigella.

Antenatal, intrapartum and infant azithromycin to prevent stillbirths and infant deaths: study protocol for SANTE, a 2×2 factorial randomised controlled trial in Mali.

INTRODUCTION: In high mortality settings, prophylactic azithromycin has been shown to improve birth weight and gestational age at birth when administered antenatally, to reduce the incidence of neonatal infections when administered intrapartum, and to improve survival when administered in infancy. Questions remain regarding whether azithromycin can prevent stillbirths, and regarding the optimal strategy for the delivery of azithromycin to pregnant women and their infants. METHODS AND ANALYSIS: Sauver avec l'Azithromycine en Traitant les Femmes Enceintes et les Enfants (SANTE) is a 2×2 factorial, individually randomised, placebo-controlled, double-masked trial in rural Mali. The primary aims are: (1A) to assess the efficacy of antenatal and intrapartum azithromycin on a composite outcome of stillbirths and infant mortality through 6-12 months and (1B) to assess the efficacy of azithromycin administered concurrently with the first and third doses of pentavalent vaccines (Penta-1/3) on infant mortality through 6-12 months. Pregnant participants (n=49 600) and their infants are randomised 1:1:1:1 to one of four treatment arms: (1) mother and infant receive azithromycin, (2) mother and infant receive placebo, (3) mother receives azithromycin and infant receives placebo or (4) mother receives placebo and infant receives azithromycin. Pregnant participants receive three single 2 g doses: two antepartum and one intrapartum. Infants receive a single 20 mg/kg dose at the Penta-1 and 3 visits. An additional cohort of 12 000 infants is recruited at the Penta-1 visit and randomised 1:1 to receive azithromycin or placebo at the same time points. The SANTE trial will inform guidelines and policies regarding the administration of antenatal and infant azithromycin using routine healthcare delivery platforms. ETHICS AND DISSEMINATION: This trial was approved by the Institutional Review Board at the University of Maryland School of Medicine (Protocol #HP-00084242) and the Faculté de Médecine et d'Odonto-Stomatologie in Mali. The findings of this trial will be published in open access peer-reviewed journals. TRIAL REGISTRATION NUMBER: NCT03909737.

Safety and immunogenicity of quadrivalent meningococcal polysaccharide vaccine (MPV ACYW135) compared with quadrivalent meningococcal conjugate vaccine (Menactra®) in Malian children.

Affordable, polyvalent meningococcal vaccines are needed for use in emergency reactive immunization campaigns. A phase IV randomized, observer-blind, controlled study compared the safety and immunogenicity of a quadrivalent meningococcal polysaccharide vaccine (MPV-4, MPV ACYW135) and quadrivalent meningococcal ACWY conjugate vaccine (MCV-4, Menactra®). Healthy, 2- to 10-year-old children in Bamako, Mali, were randomized 1:1 to receive one dose of MPV-4 or MCV-4. Safety outcomes were evaluated for 6 months post-immunization. Immunogenicity for all serogroups was assessed for non-inferiority between MPV-4 and MCV-4 30 days post immunization by serum bactericidal antibody assay using baby rabbit complement (rSBA). From December 2020 to July 2021, 260 healthy subjects were consented and randomized. At Day 30 post-immunization, the proportions of subjects with rSBA titers ≥ 128 for all serogroups in the MPV-4 group were non-inferior to those in MCV-4 group. The proportions of subjects with rSBA ≥ 4-fold increase and rSBA titers ≥ 8 for all serogroups were similar among vaccine groups (P > .05). Geometric Mean Titers and Geometric Mean Fold Increases for all serogroups in both vaccine groups were similar (P > .05). Few local and systemic post-immunization reactions of similar severity and duration were observed within 7 days and were similar in both groups (P > .05). All resolved without sequelae. Unsolicited adverse events were similar in both groups regarding relationship to study vaccine, severity and duration. No serious adverse events were reported during the study period. MPV ACYW135 showed a non-inferior immunogenicity profile and a comparable reactogenicity profile to MCV-4 in Malian children aged 2-10 years.Clinical Trial Registration: NCT04450498.