Attitudes and practices of travelers regarding COVID-19 vaccine and adverse reactions

Objective.In the context of the global COVID-19 pandemic, COVID-19 vaccines were made available to different countries. This study aimed to assess travelers' attitudes and practices toward the COVID vaccine and adverse events. Methods. A survey was conducted using a questionnaire from April 1 to June 30, 2021, among travelers who came for their COVID-19 test at the Institut Pasteur of Côte d'Ivoire.Results. A total of 527 travelers agreed to participate in this study, including 336 men and 161 women. Overall, 26% of respondents had already received their COVID-19 vaccine, while 76% of respondents responded they did not want to be vaccinated. The age of those most vaccinated (116) ranged from 25 to 64 years with a small proportion for those over 65 years (0.8%). Travelers (41) to France were the most vaccinated. All vaccinated persons (135) had a high level of education and were either Christian (89 persons), Muslim (45 persons) or animist (1 person). Adverse events related to the COVID vaccination were reported in seven individuals. These included muscle pain, fever and nausea. Conclusion.Negative attitudes towards vaccines are a major public health concern. In view of these results, for awareness raising, vaccination campaign may be focused on youthand people over 65 years of age. Public health messages containing information about vaccine safety should be tailored to address this vaccine hesitancy

Mathematical modelling approach of the study of Ebola virus disease transmission dynamics in a developing country

Background: Ebola Virus causes disease both in human and non-human primatesespecially in developing countries. In 2014 during its outbreak, it led to majority of deaths especially in some impoverished area of West Africa and its effect is still witnessed up till date. Materials and Methods:We studied the spread of Ebola virus and obtained a system of equations comprising of eighteen equations which completely described the transmission of Ebola Virus ina population where control measures were incorporated and a major source of contacting the disease which is the traditional washing of dead bodies was also incorporated. We investigated the local stability of the disease-free equilibrium using the Jacobian Matrix approach and the disease-endemic stability using the center manifold theorem. We also investigated the global stability of the equilibrium points using the LaSalle's Invariant principle.Results: The result showed that the disease-free and endemic equilibrium where both local and globally stable and that the system exhibits a forward bifurcation.Conclusions: Numerical simulations were carried out and our graphs show that vaccine and condom use is best for susceptible population, quarantine is best for exposed population, isolation is best for infectious population and proper burial of the diseased dead is the best to avoid further disease spread in the population and have quicker and better recovery.

A review of the epidemiology, diagnosis, treatment, vaccines and economic impact of human monkeypox (Mpox) outbreaks

The current monkeypox outbreak is a public health emergency of international concern and is coming in the wake of the SARS-CoV-2 pandemic. Human monkeypox is a viral zoonotic infection caused by monkeypox virus, an enveloped double-stranded DNA virus of the genus Orthopoxvirus and family Poxviridae that also contain smallpox, cowpox, Orf, and vaccinia viruses. Online databases including PubMed, Google Scholar and Web of Science were searched to obtain relevant publications on the epidemiology, treatment, vaccines and the economic impacts of the current monkeypox (Mpox) outbreak.

Determinants of COVID-19 vaccine acceptance amongst doctors practising in Cross River State, Nigeria

Background: COVID-19 vaccine is one of the most effective public health intervention approaches for prevention of COVID-19. Despite its well-known efficacy and safety, significant proportion of frontline COVID-19 healthcare workers remain hesitant about accepting the vaccine for whatever reasons. This study aimed to determine acceptance rate and determinants of vaccine refusal among doctors in Cross River State, Nigeria. Methodology: This was a cross-sectional survey of doctors using structured online questionnaire administered via the WhatsApp platform of the medical doctors' association, in order to assess their rate of acceptance of COVID-19 vaccines, and reasons for vaccine refusal. The predictors of vaccine acceptance were analysed by univariate and multivariate logistic regression analyses. Results: Of the 443 medical doctors targeted on the WhatsApp platform, 164 responded to the questionnaire survey, giving a response rate of 37.0% (164/443). The mean age of the respondents is 38 ±6.28 years, 91 (55.5%) are 38 years old and above, 97 (59.1%) are males and 67 (40.9%) are females, giving a male-to-female ratio of 1.4:1. The greater proportion of the respondents are physicians (70/148, 47.3%) and about three-quarter of the participants (127/164, 77.4%) had received COVID-19 vaccine. The proportion of physicians who had received COVID-19 vaccine (57/70, 81.4%) was more than the proportion of general practitioners (31/42, 73.8%) and surgeons (24/35, 68.6%). Low perceived benefit of vaccination was the main reason given for COVID-19 vaccine refusal (45.9%, 17/37). No significant association was found between vaccine refusal and suspected predictors (p>0.05). Conclusion: Our study revealed high rate of COVID-19 vaccine acceptance among medical doctors especially among the physicians, with the surgeons showing lowest acceptance rate. A significant proportion would not take vaccine because they perceived it lacks much benefits. To raise vaccine acceptance among doctors, more efforts on vaccine literacy that would target doctors from all sub-specialties especially surgeons and incorporate vaccine benefits should be made.

A review of the recent advances on Lassa fever with special reference to molecular epidemiology and progress in vaccine development

Lassa fever, a viral hemorrhagic fever caused by the Lassa virus (LASV), is endemic in West Africa and is associated with high morbidity and mortality. At least three of the four proposed seven lineages of LASV are found in Nigeria, where the multimammate rat, Mastomys natalensis, serves as the primary reservoir. Endemic countries report approximately 200,000 infections and 5,000 deaths annually, with Nigeria experiencing thousands of infections and hundreds of deaths including healthcare workers. The aim of this review is to provide scientific information for better understanding of the evolutionary biology, molecular epidemiology, pathogenesis, diagnosis, and prevention of Lassa fever in Nigeria and other endemic regions worldwide, which can lead to improved control efforts and reduce morbidity and mortality from recurrent epidemics. To achieve this aim, observational studies such as case series, cross-sectional and cohort studies published between December 2017 and September 2022 were searched for on various online databases including Google Scholar, Africa Journals Online (AJOL), Research Gates, PubMed, PMIC, NCDC, and WHO websites. Although the origin and evolutionary history, and the transmission dynamics of Lassa virus have been revealed through recent molecular epidemiological studies, the factors that drive the evolution of the virus remain unclear. Genetic changes in the viral genome may have enabled the virus to adapt to humans. Diagnosis of Lassa fever has also advanced from basic serological tests to more sophisticated methods such as quantitative real time polymerase chain reaction (qRT-PCR) and sequencing, which are particularly useful for identifying outbreak strains. Several vaccines, including recombinant vesicular stomatitis virus (rVSV), virus-like particle (VLP), and DNA-based vaccines, have shown promise in animal models and some have progressed to phase 2 clinical trials. Preventing and controlling Lassa fever is critical to safeguard the health and well-being of affected communities. Effective measures such as rodent control, improved sanitation, and early detection and isolation of infected individuals are essential for reducing transmission. Ongoing research into the genetic and ecological factors that drive the evolution of Lassa virus is necessary to reduce the impacts of Lassa fever

La fièvre de Lassa, une fièvre hémorragique virale causée par le virus de Lassa (LASV), est endémique en Afrique de l'Ouest et est associée à une morbidité et une mortalité élevées. Au moins trois des quatre lignées proposées de LASV se trouvent au Nigeria, où le rat multimammaire, Mastomys natalensis, sert de réservoir principal. Les pays endémiques signalent environ 200,000 infections et 5,000 décès par an, le Nigéria connaissant des milliers d'infections et des centaines de décès, y compris des travailleurs de la santé. L'objectif de cette revue est de fournir des informations scientifiques pour une meilleure compréhension de la biologie évolutive, de l'épidémiologie moléculaire, de la pathogenèse, du diagnostic et de la prévention de la fièvre de Lassa au Nigeria et dans d'autres régions endémiques du monde, ce qui peut conduire à des efforts de contrôle améliorés et réduire la morbidité et la mortalité des épidémies récurrentes. Pour atteindre cet objectif, des études observationnelles telles que des séries de cas, des études transversales et de cohorte publiées entre décembre 2017 et septembre 2022 ont été recherchées sur diverses bases de données en ligne, notamment Google Scholar, Africa Journals Online (AJOL), Research Gate, PubMed, PMIC, Sites Web du NCDC et de l'OMS. Bien que l'origine et l'histoire évolutive, ainsi que la dynamique de transmission du virus de Lassa aient été révélées par des études épidémiologiques moléculaires récentes, les facteurs qui déterminent l'évolution du virus restent flous. Des modifications génétiques du génome viral pourraient avoir permis au virus de s'adapter à l'homme. Le diagnostic de la fièvre de Lassa est également passé des tests sérologiques de base à des méthodes plus sophistiquées telles que la réaction quantitative en chaîne par polymérase en temps réel (qRTPCR) et le séquençage, qui sont particulièrement utiles pour identifier les souches épidémiques. Plusieurs vaccins, y compris le virus recombinant de la stomatite vésiculeuse (rVSV), les particules pseudo-virales (VLP) et les vaccins à base d'ADN, se sont révélés prometteurs dans des modèles animaux et certains ont progressé vers des essais cliniques de phase 2. La prévention et le contrôle de la fièvre de Lassa sont essentiels pour préserver la santé et le bien-être des communautés touchées. Des mesures efficaces telles que le contrôle des rongeurs, l'amélioration de l'assainissement et la détection et l'isolement précoces des personnes infectées sont essentielles pour réduire la transmission. Des recherches continues sur les facteurs génétiques et écologiques qui déterminent l'évolution du virus de Lassa sont nécessaires pour réduire les impacts de la fièvre de Lassa.

Developing capacity for implementation and evaluation of vaccine trials in Uganda: Perspective of the Makerere University Walter Reed Project

Introduction: Infectious diseases and neglected tropical diseases continue to be a major challenge in resource limited settings, causing significant morbidity and mortality. Although vaccines are a key biomedical prevention tool, resource limited settings often lack the infrastructure, regulatory frameworks, and skilled human resource to conduct vaccine clinical trials. To address this gap, the Makerere University Walter Reed Project (MUWRP) was established and has contributed to vaccine research in Uganda and globally. Methods: This was achieved through training a strong vaccine clinical trial workforce; development of requisite clinical trial infrastructure for research activities and management of investigational products; conducting phase I-III vaccine trials and contribution to national ethical and regulatory frameworks that protect participants. Results: As of 2022, MUWRP had successfully conducted and completed five phase I/II HIV vaccine clinical trials, five for Ebola and Marburg, while one phase I/II Schistosomiasis and one phase III COVID-19 vaccine clinical trial are ongoing. Discussion: The completed vaccine trials provided critical scientific knowledge on the safety and immunogenicity of investigational products which informed the design of better vaccines for diseases of global health importance. Conclusion: Academia, through establishment of appropriate partnerships can contribute to the identification of solutions to complex public health challenges

Determinants of COVID-19 vaccine acceptance and hesitancy among healthcare professionals in the Kintampo North Municipality, Bono East Region, Ghana

tives: To assess the determinants of COVID-19 vaccine acceptance and hesitation among Health Care Professionals (HCPs) in the Kintampo North Municipality of Ghana. Design: An analytical cross-sectional study. Setting: The study was carried out in the Kintampo North Municipality. Participants: All health care professionals within the Kintampo North Municipality of Ghana. Main outcome measure: Acceptance of COVID-19 vaccine. Results: In all, 215 HCPs were included in this study. The overall vaccine acceptance was 78.6% among HCPs, while 21.4% were hesitant to receive the COVID-19 vaccine. Majority (57.7%) of HCPs believed that COVID-19 vaccines were safe. The following factors were found to influence vaccine acceptance significantly; those who knew someone who has taken the vaccine (adjusted Odds Ratio [aOR]; 14.9, 95% Confidence Interval [95% CI];5.0-45.0, p<0.001), those who think COVID -19 vaccine in Ghana was safe (AOR;9.2, 95%CI;3.3-25.8, P<0.001), those who said vaccines are effective in controlling COVID-19 transmission (aOR=5.0, 95%CI;2.1-12.4, p<0.001), and those who have never refused vaccines in the past (aOR=7.8, 95CI;1.6-37.8, p=0.01). Conclusion: The study indicated high COVID-19 vaccination acceptability among HCPs. However, some HCPs are hesitant to take COVID-19 vaccinations immediately. Increased adoption of COVID-19 vaccinations among HCPs and the broader Ghanaian population requires concerted efforts, including strengthening public health education on the perceived risks and safety of COVID-19 vaccines

Nigeria vaccine policy

Vaccines are recognised globally for their importance in the reduction of vaccines preventable diseases to improve the quality of life of the entire population. The importance of vaccines has been further demonstrated with the COVID-19 outbreak with countries scrambling to produce vaccines to combat the effect of the pandemic amongst their citizens. The purpose of this Vaccine Policy is to address the goal and objectives of achieving availability, self-sufficiency and vaccine security in the country. It is hoped that the development of this Policy will complement the already existing Immunisation Policy and provide the platform for the amelioration of vaccine-preventable diseases in Nigeria. Highlights of the Policy include: its vision, mission, goal, objectives, targets and implementation strategies for achieving local vaccines production and ownership of the vaccines supply chain management processes towards vaccine availability and security in the country. To achieve these, the Policy needs to be implemented and monitored hence the Policy provides for the establishment of appropriate governing structures to oversee the implementation process. The governing council and its various structures will pursue the achievement of the goal and objectives of the Policy. They will mobilise resources from the governments across all levels, individuals, the international communities, donor agencies. Other critical areas include the resuscitation of local production of vaccines, intensification of research and development and strengthening of the legislature and regulatory agencies to support the quality and safety of vaccines in Nigeria. It is recommended that all stakeholders responsible for implementing this policy should work collaboratively to ensure the goal and objectives are met

Vaccine hesitancy among medical practitioners

Background: Vaccine hesitancy defined as "delay in acceptance or refusal of vaccination despite availability of vaccination services is a global phenomenon. There have been anecdotal evidence or rather poor documentation of hesitancy or noncompliance among medical practitioners in Northern Nigeria. Objective: We explored the perceptions and perspectives of doctors in Kebbi State, Nigeria, on immunization programs. Materials and Methods: We conducted this cross­sectional study involving 63 medical doctors, whose self­administered questionnaires were analyzed using descriptive statistics. Results: Only 43.55% of the doctors reported having under­five children with complete vaccination, whereas 84% of the doctors surveyed had a child or a relative with a child who had missed routine immunization (RI) previously. Approximately 66.67% and 67.74% of the doctors believed in the quality of the vaccine and capacity of the health workers to effectively deliver polio supplementary immunization activities (PSIAs), respectively. Adequate training of workers (26.23%) and public enlightenment campaigns (23.68%) were suggested as PSIAs enhancers. Collaboration with community and religious leaders (29.2%), education and public sensitization (28.09%), and improved government funding (13.48%) to improve RI were suggested. Others include incentives and fines (8.99%), adequate training of staff (10.11%), house­to­house vaccination (4.49%), and media publicity (5.62%). Conclusion: Vaccine hesitancy among medical doctors could be a threat to sustained polio interruption and efforts toward improving RI in Kebbi State. The state government and development partners should modify the current approaches to attaining polio­free certification standards and strengthen RI in the state. In addition, there is a need to improve sensitization of doctors in the state on vaccines and their safety profiles with a view to reducing vaccine hesitancy among them

Contribution of plastic bags to the retention of child immunization cards in Gambella Region and Assosa Zone, Benishangul-Gumuz Region, Ethiopia

Background: Many vaccines are given more than once, at different ages, and in combinations. Parents are expected to retain immunization cardsfor their children, however in Ethiopia,the retention of child immunization cardsis minimal. For example,the 2005 and 2011 Ethiopian Demographic and Health Surveysshowed that 37% and 29% of immunization cards, respectively, were retained. The CORE Group Polio Project developed an innovative approach to keeping home vaccination records for a long time and safely,in the form of a plastic bag designed to hold the immunization card. The pilot project for this innovation was held in Gambella Region and Assosa Zone, Benishangul-Gumuz Region since 2015. Objective: Evaluate the contribution of plastic bags for holding and retaining child immunization cards in Gambella Region and Assosa Zone, Benishangul-Gumuz Region. Methods: The study was a household-based cross-sectional survey and the target population was households with at least one child aged under 2years who had received at least one vaccination dose. A sample of 239 households (120 from Gambella Region and 119 from Assosa Z one in Benishangul-Gumuz Region) were selected randomly from immunization registration records. Up to 12 kebeles were included from each region, with at least 10 children per kebele. Data were collected using an Amharic language questionnaire and analyzed with STATA version 13.0. Results: Of all 239 respondents, 139 (58.2%) received the plastic bag for retaining immunization cards, while 100 (41.8%) did not receive the bag. Of the 139 respondents who received immunization cards, 125 (89.9%) utilized the plastic bag. Of those that utilized the bags to hold immunization cards, 50.4% were from Gambella Region and 49.6% were from Benishangul-Gumuz Region. A total of 125 (58.7%) respondents were presented with the immunization card inside the plastic bag, and 88 (41.3%) respondents received the immunization card with no accompanying plastic bag. However, of all respondents who received the plastic bag, 14 (10%) did not put the card inside it. The reasons given by respondents were that it was difficult to put the card inside the plastic bag(seven cases, (58.3%))and that it was lost/damaged or used for some other purpose (five cases, (41.7%)).A total of 145(70%)respondents reported that they placed the plastic bag that contains the immunization card in a secure place, such as in a box, and 53 (25.6%) hung it on a wall.Conclusion:In general, there was89.5% card retention;90% of respondents utilized the plastic bag,and 88% of mothers said they would advise others to use the plastic bag

Immune protection of Hepatitis B vaccine among children living in gondar, Northwest Ethiopia

Background: Hepatitis B virus infection is a worldwide health problem and highly endemic in developing countries including Ethiopia. Hepatitis B vaccine is included in the routine Expanded Program on Immunization since 2007 in Ethiopia. Objective: The aim of this study is to assess the seroprotection level of hepatitis B vaccination among children who have received the vaccine. Methods: A cross-sectional study was conducted on children attending kindergarten and elementary school in Gondar. A pretested structured questionnaire was used to collect the sociodemographic data. Blood samples were collected and serum separated to measure anti-HBs, anti-HBc, and HBsAg levels. Data were analyzed using SPSS statistical software version 21. Binary logistic regression analysis was done. P-value less than 0.05 was considered as statistically significant. Results: Out of 431 children screened, 27 were excluded from analysis because they were positive for anti-HBc (27/431, 6.3%) and/or for HBsAg (18/431 or 4.2%). Out of the rest 404 children, 130 (32.2%) had anti-HBs titers >10 mIU/ml (seroprotected), while 274 (68.8%) had anti-HBs titers <10 mIU/ml (non-protected). Among 130 sero-protected children, 99 (76.2%) were hypo-responders (antibody titer 10-100 mIU/ml) and 31 (23.8%) were good responders (antibody titer >100 mIU/ml). In multivariate analysis, children of age 6 and 8 years old were 2.4 times (AOR: 2.436, 95% CI 1.049-5.654) (P=0.038) and 3.3 times (AOR: 3.397, 95% CI1.306-8.837) (p=0.012) better responders compared to 9 years old children, respectively. Moreover, children whose mothers had no previous history of hepatitis were 2.0 times (AOR: 2.009, 95% CI 1.101-3.665) (P= 0.023) better responders compared to their counterparts. Conclusion: The seroprotection level among vaccinated children in Gondar was surprisingly low. Age and children from mothers with a history of hepatitis B infection were associated with seroprotection. The preliminary findings obtained in this study call for a thorough assessment of the effectiveness of the current hepatitis B vaccination program in this study region

Seroprevalence of Hepatitis B virus infection and seroprotection of Hepatitis B vaccine among children in Jimma Town, South-West Ethiopia

Background: Hepatitis B virus is the leading cause of viral hepatitis and about 240 million people worldwide are chronic carriers. The virus is reported to be widely prevalent in Ethiopia and routine vaccination of children has been initiated in the country recently. We assessed the seroprevalence of HBV infection and seroprotection of HBV vaccine among children in Jimma. Methods: A community-based cross-sectional study was conducted among 900 children who were 5-9 years of age between June and December 2016. A simple random sampling technique was employed to recruit study participants by proportional allocation into different Kebeles of Jimma. Data were collected using pretested questionnaire.3-5ml of blood sample was collected from each child and it was tested for HBsAg, anti-HBc, and anti-HBs using ELISA (Bio-rad, Monolisa, Lacquote, France). Data were analyzed using chi-square and logistic regression analysis. Result: HBsAg and anti-HBc prevalence among all participants was 3.5% and 3.8%, respectively. The prevalence of HBsAg among vaccinated and non-vaccinated children was 2.1% and 7.0% whereas anti-HBc positivity was 1.1% and 6.2%, respectively. It was also found that 58.4% of vaccinated children maintained a protective level of HB surface antibodies which is defined as ≥ 10 mIU/ml anti-HBs. While 1.8%(4/222) vaccinated children with protective anti-HBs levels were positive for hepatitis B core antibody, none of the vaccinated children with non-protective anti-HBs levels were positive for hepatitis B core antibody. Multi-variable logistic regression revealed that lack of vaccination (AOR =2.788, P < 0.029), children who were born at home (AOR= 3.211, P < 0.009), and children who had a history of hospital admission (AOR= 7.122, P <0.001) were more likely to be HBV surface antigen positive. Conclusion: The seroprevalence of hepatitis B infection is high among children who have not received HBV vaccination. Hepatitis B vaccine has contributed to the reduction of the infection in this endemic area, though further efforts are required to improve timely vaccination and its coverage. The prevalence of protective anti-HBs is low among fully vaccinated children, hence, it is better to include the monovalent birth dose of the vaccine and conduct further studies to evaluate underlining causes for the waning of serum anti-HBs level

Challenges in the logistics management of vaccine cold chain system in Ile-Ife, Osun State, Nigeria

Background: The success of national immunization programmes depends largely on effective logistics management of the vaccine cold chain system. This study assessed cold chain equipment functionality, healthcare workers' knowledge and practice of the logistics management of vaccine cold chain system in Ile-Ife, Nigeria. Methods: A descriptive study was conducted in immunization clinics of 35 health facilities in Ife East and Central Local Government Areas (LGA) in Ile-Ife. There were 100 immunization service providers in the (LGAs) and they were all recruited into the study. Information was obtained with the aid of an interviewer-administered, structured questionnaire. Cold chain equipment functionality was assessed using a checklist. Data were analyzed using SPSS version 20.0. Results: Eleven (31.4%) of the facilities had functional refrigerators for storing vaccines, 16 (45.7%) had cold boxes while 13 (37.1%) had thermometers for vaccine temperature monitoring. Fifty-four (54.0%) of the healthcare workers were aware of the "shake test" and 19 (19.0%) could correctly interpret colour changes on a vaccine vial monitor. Consumption record was considered by 69 (69.0%) of healthcare workers when making vaccine requisitions while the required lead time was considered by 24 (24.0%) of them. Only 29 (29.0%) of healthcare workers kept records of vaccines stock-on-hand.Conclusion: Adequate training and supportive supervision is essential to improve healthcare workers' knowledge and cold chain practices. Relevant cold chain equipment should be provided to boost storage capacity across health facilities

Vaccine Safety and Pharmacovigilance in the African Region

In recent years the WHO African Region has seen a growth in clinical development of new vaccines as well as their introduction into the national immunization programmes of many countries. Recognizing the critical need for vaccine safety and pharmacovigilance; WHO has been supporting individual and institutional capacity building in the Region to strengthen the monitoring and response to adverse events following immunization through implementation of the Global Vaccine Safety Blueprint. This framework is discussed along with general points about the importance of ensuring vaccine safety and the system needed to enable this. The article ends with a brief overview of the status of vaccine safety and pharmacovigilance and the key priorities for countries in the Region for the immediate future

Surveillance for Diseases Targeted by new Vaccines: Progress; Challenges and Way Forward

Thirteen years ago; WHO-AFRO proposed the establishment of a sentinel disease surveillance network as part of efforts to improve surveillance for invasive bacterial diseases (IBD) including paediatric pneumonia and meningitis and rotavirus diarrhoea in all Member States as part of surveillance for vaccine-preventable diseases and in line with the regional strategy integrated disease surveillance and response (IDSR). This was prompted by the eminent availability of new and prospective vaccines against Haemophilus influenzae type b (Hib); Streptococcus pneumoniae (S. pneum); Neisseria meningitides (Nm) and rotavirus vaccines. The Regional Office for Africa developed guidelines and tools and standardized methodology; including cases definitions to be used to recruit eligible cases. This article outlines the challenges and results of this initiative to date and aims for the future

Control of Meningococcal Meningitis Outbreaks in Sub-Saharan Africa

Outbreaks of Neisseria meningitidis recur frequently in the African Sahel where they are responsible for high mortality and morbidity; especially in children. An effective vaccine has been in existence for more than 30 years; but despite this; the control of epidemics has failed. Moreover; the geographical distribution of N. meningitidis seems to be increasing; perhaps because of climate change but also because of the economic crisis which prevails throughout much of Africa leading to population movements and the breakdown of essential services. Although alarming; the emergence of new serogroups in recent epidemics (such as serogroups X and W135) should not mask the fact that serogroup A remains the most common meningococcal isolate from meningitis cases and is therefore the most significant target for control. The development of a low-cost conjugate meningococcal vaccine should support a strategy of preventive immunization; as this strategy is one that appears most effective to control this plague

Pneumococcal disease in sub-Saharan African children: what is the effectiveness of the pneumococcal conjugate vaccine?

Streptococcus pneumoniae is still a leading cause of morbidity and mortality among children in developing countries. Young children represent a high-risk group for severe pneumococcal disease; not only because of their physio-logical susceptibility but also because polysaccharide vaccines are not effective for them. Pneumococcal conjugate vaccines have shown a high protection against pneumococcal diseases all over the world. Therefore; the expanded use of this vaccine must be considered as a major world health priority

An economic evaluation of the controlled temperature chain approach for vaccine logistics: evidence from a study conducted during a meningitis A vaccine campaign in Togo

Introduction: a recent innovation in support of the final segment of the immunization supply chain is licensing certain vaccines for use in a controlled temperature chain (CTC), which allows excursions into ambient temperatures up to 40°C for a specific number of days immediately prior to administration. However, limited evidence exists on CTC economics to inform investments for labeling other eligible vaccines for CTC use. Using data collected during a MenAfriVac™ campaign in Togo, we estimated economic costs for vaccine logistics when using the CTC approach compared to full cold chain logistics (CCL) approach.Methods: we conducted the study in Togo's Central Region, where two districts were using the CTC approach and two relied on a fullCCL approach during the MenAfriVac™ campaign. Data to estimate vaccine logistics costs were obtained from primary data collected using costing questionnaires and from financial cost data from campaign microplans. Costs are presented in 2014 US dollars.Results: average logistics costs per dose were estimated at $0.026±0.032 for facilities using a CTC and $0.029±0.054 for facilities using the fullCCL approach, but the two estimates were not statistically different. However, if the facilities without refrigerators had not used a CTC but had received daily deliveries of vaccines, the average cost per dose would have increased to $0.063 (range $0.007 to $0.33), with larger logistics cost increases occurring for facilities that were far from the district.Conclusion: using the CTC approach can reduce logistics costs for remote facilities without cold chain infrastructure, which is where CTC is designed to reduce logistical challenges of vaccine distribution

A study of Physico-Chemical Interactions between Haemophilus Influenzae Type b and Meningococcus group C Conjugate Vaccines

Background: Haemophilus influenzae type b (Hib) and Meningococcal group C (MenC) conjugate vaccines; which protect against otitis media; bacteremia and invasive diseases; including pneumonia and meningitis; are attractive candidates for combination; since they are both administered to infants and children.A Hib-MenC combination booster at 12 mo has recently been introduced in the U.K. Objectives: To rule out the possibility for the individual vaccine components in a Hib-MenC combination to interact; rendering one or both of them less effective; this work assessed whether these two saccharide-protein conjugates; namely; Hib oligosaccharideCRM197 (Cross-Reacting Material 197) and MenC-CRM197; interact in solution. Furthermore an evaluation of the size and integrity of the vaccines was also performed. Methods: HPLC Size-exclusion chromatography (SEC) with UV-adsorption and refractive index detection was performed with a phosphate and non-phosphate saline buffer to characterize the size of Hib and MenC conjugates as individual components or when combined. Results: Hib-CRM197 eluted significantly earlier than MenC-CRM197 in both phosphate-saline and MOPS-saline buffers on a TSK5000 PWXL column.When combined; there was no significant change in their elution. Refractive index monitoring showed no evidence of significant free saccharide or free protein. Conclusions: By size-exclusion chromatography and refractive index detection methods; there was no indication of degradation; and no evidence of significant associative interactions between Hib-CRM197 and MenC-CRM197 in saline-based buffers; pH 7.2