Gender and intersectional analysis of livestock vaccine value chains in Kaffrine, Senegal

Among livestock species, poultry and small ruminants are of particular importance to rural women in low- and middle-income countries, as means to generate income, provide nutritious food for the family, accumulate wealth, and confer social status. Newcastle disease (ND) and Peste des Petits Ruminants (PPR) are widespread livestock diseases of poultry and small ruminants, respectively. While both diseases are vaccine preventable, numerous constraints limit the availability of and access to livestock vaccines, especially among the most vulnerable populations in developing countries. The literature on equity and effectiveness of livestock vaccine distribution systems has emphasized many of these constraints, however a gendered analysis and deeper understanding of the vaccine system remain insufficient. This paper applies a gendered and intersectional transformational approach, or GITA, to highlight how gender and other social factors affect the provision and utilization of vaccines for ND and PPR diseases in the region of Kaffrine, Senegal. We first articulate and describe the vaccine value chains (VVCs) for these diseases in Kaffrine, and then analyze the gendered and intersectional dynamics at different nodes of the VVCs, including actors at the national level, through the regional and district levels, down to providers of animal health at community level and the livestock keepers themselves. Our findings indicate that actors’ various experiences are shaped and defined mainly by rigid gender norms, location and remoteness, and to a lesser degree by other social stratifications of age, ethnicity, and livelihood. Given the significant role that gender norms play in the livestock vaccine value chains, differences according to the livestock species, regulation of vaccine administration, and vaccine distribution systems emerge as highly relevant for understanding barriers that women specifically face within the livestock vaccination system.

Optimal allocation of limited vaccine to control an infectious disease: Simple analytical conditions

When allocating limited vaccines to control an infectious disease, policy makers frequently have goals relating to individual health benefits (e.g., reduced morbidity and mortality) as well as population-level health benefits (e.g., reduced transmission and possible disease eradication). We consider the optimal allocation of a limited supply of a preventive vaccine to control an infectious disease, and four different allocation objectives: minimize new infections, deaths, life years lost, or quality-adjusted life years (QALYs) lost due to death. We consider an SIR model with n interacting populations, and a single allocation of vaccine at time 0. We approximate the model dynamics to develop simple analytical conditions characterizing the optimal vaccine allocation for each objective. We instantiate the model for an epidemic similar to COVID-19 and consider n=2 population groups: one group (individuals under age 65) with high transmission but low mortality and the other group (individuals age 65 or older) with low transmission but high mortality. We find that it is optimal to vaccinate younger individuals to minimize new infections, whereas it is optimal to vaccinate older individuals to minimize deaths, life years lost, or QALYs lost due to death. Numerical simulations show that the allocations resulting from our conditions match those found using much more computationally expensive algorithms such as exhaustive search. Sensitivity analysis on key parameters indicates that the optimal allocation is robust to changes in parameter values. The simple conditions we develop provide a useful means of informing vaccine allocation decisions for communicable diseases.

Strategic spatiotemporal vaccine distribution increases the survival rate in an infectious disease like Covid-19

Present hopes to conquer the Covid-19 epidemic are largely based on the expectation of a rapid availability of vaccines. However, once vaccine production starts, it will probably take time before there is enough vaccine for everyone, evoking the question how to distribute it best. While present vaccination guidelines largely focus on individual-based factors, i.e. on the question to whom vaccines should be provided first, e.g. to risk groups or to individuals with a strong social-mixing tendency, here we ask if a strategic spatiotemporal distribution of vaccines, e.g. to prioritize certain cities, can help to increase the overall survival rate of a population subject to an epidemic disease. To this end, we propose a strategy for the distribution of vaccines in time and space, which sequentially prioritizes regions with the most new cases of infection during a certain time frame and compare it with the standard practice of distributing vaccines demographically. Using a simple statistical model we find that, for a locally well-mixed population, the proposed strategy strongly reduces the number of deaths (by about a factor of two for basic reproduction numbers of [Formula: see text] and by about 35% for [Formula: see text]). The proposed vaccine distribution strategy establishes the idea that prioritizing individuals not only regarding individual factors, such as their risk of spreading the disease, but also according to the region in which they live can help saving lives. The suggested vaccine distribution strategy can be tested in more detailed models in the future and might inspire discussions regarding the importance of spatiotemporal distribution rules for vaccination guidelines.

An ethical framework for global vaccine allocation

The Fair Priority Model offers a practical way to fulfill pledges to distribute vaccines fairly and equitably

The Challenges of Vaccine Development against a New Virus during a Pandemic

The rapid emergence of a highly pathogenic, readily transmissible coronavirus has resulted in a global pandemic, affecting millions and destabilizing economies. This catastrophe triggered a clarion call for the immediate deployment of a protective vaccine. We describe the unique challenges of developing a vaccine against SARS-CoV-2 in a pandemic setting.

[Antiviral therapy for general practitioners]

Viral infections are extremely common and generally self-restricted, thus antiviral therapy is limited to precise indications. Apart from HIV (not reviewed in this article), the principal treatable viruses are HSV 1 and 2, VZV, CMV, Influenza A and B, and hepatitis B and C. Vaccination is another cornerstone of viral infections control. This article summarizes actual and available therapy. New treatments arrived recently on the market or are being developed : HCV can now be treated with a high success rate, baloxavir against the flu, a new zoster vaccine will probably soon be available in Switzerland and letermovir improves CMV prophylaxis in the case of hematopoietic stem cell transplant.

The livestock vaccine supply chain: Why it matters and how it can help eradicate peste des petits Ruminants, based on findings in Karamoja, Uganda

Understanding factors that hinder vaccination, including logistical and social constraints, is critical to finding the most effective approach for the global eradication of peste des petits ruminants (PPR). Vaccination projects should analyze the supply chain and take it into consideration when planning and creating a vaccination strategy. Adequate supply chain management of the PPR vaccine could lead to reduced cost, increased availability, and the construction of a data platform for other livestock vaccines. Integrating the supply chain of PPR vaccine with other veterinary or health commodities could reduce cost, as well as increase uptake. The use of a thermostable vaccine could potentially have a positive impact on the eradication of PPR in remote areas, such as the Karamoja subregion in Uganda, as it did with rinderpest across Sub Saharan Africa. In terms of vaccine delivery, the use of community animal health workers (CAHWs) could be beneficial in certain areas, such as the Karamoja subregion of Uganda, by alleviating supply chain constraints in the last-mile delivery, as well as increasing coverage and uptake. A gendered approach to livestock vaccines should also be considered, as decision-making power regarding livestock vaccination is gendered in many various contexts. The PPR eradication strategy-as well as other livestock vaccination programs-would be more effective and efficient if the supply chain management were considered as a key component in the process and efforts tailored, accordingly.

Zika virus knowledge, attitudes, and vaccine interest among university students

BACKGROUND

Zika virus vaccine development is underway. We examined interest in receiving a Zika virus vaccine (after one becomes commercially available) among students at a large public university in Northern Virginia.

METHODS

An online survey of Zika virus-related knowledge, attitudes, and interest in receiving a Zika vaccine was completed by 619 undergraduate students in April, 2016. Stepwise logistic regression with backward elimination was used to identify the variables most strongly associated with interest in being vaccinated against Zika virus.

RESULTS

More than half of participants (52.8%) reported that they would be likely or very likely to be vaccinated against Zika virus. Vaccination interest was significantly higher among participants who received an influenza vaccine in the past year (p=0.002), had higher levels of knowledge about Zika virus (p=0.046), reported knowing where to access information about Zika virus (p=0.041), had higher perceived susceptibility to Zika virus (p<0.001), and believed that the U.S. Government should prioritize actions to control Zika virus (p=0.001).

CONCLUSIONS

Communication and intervention strategies encouraging vaccine uptake may benefit from increasing knowledge of Zika virus, addressing perceived susceptibility, and reaching students, travelers, and others who may be seeking information about prevention of Zika virus and other emerging infectious diseases.

Beyond Oncolytics: E1B55K-Deleted Adenovirus as a Vaccine Delivery Vector

Type 5 human adenoviruses (Ad5) deleted of genes encoding the early region 1B 55-kDa (E1B55K) protein including Onyx-015 (dl1520) and H101 are best known for their oncolytic potential. As a vaccine vector the E1B55K deletion may allow for the insertion of a transgene nearly 1,000 base pairs larger than now possible. This has the potential of extending the application for which the vectors are clinically known. However, the immune priming ability of E1B55K-deleted vectors is unknown, undermining our ability to gauge their usefulness in vaccine applications. For this reason, we created an E1B55K-deleted Ad5 vector expressing full-length single chain HIV_BaLgp120 attached to a flexible linker and the first two domains of rhesus CD4 (rhFLSC) in exchange for the E3 region. In cell-based experiments the E1B55K-deleted vector promoted higher levels of innate immune signals including chemokines, cytokines, and the NKG2D ligands MIC A/B compared to an E1B55K wild-type vector expressing the same immunogen. Based on these results we evaluated the immune priming ability of the E1B55K-deleted vector in mice. The E1B55K-deleted vector promoted similar levels of Ad5-, HIVgp120, and rhFLSC-specific cellular and humoral immune responses as the E1B55K wild-type vector. In pre-clinical HIV-vaccine studies the wild-type vector has been employed as part of a very effective prime-boost strategy. This study demonstrates that E1B55K-deleted adenoviruses may serve as effective vaccine delivery vectors.

Shot in the arm. H1N1 vaccine is headed to state health departments to ward off pandemic's spread, but experts worry about delay

While the federal government has been praised for its response to the H1N1 virus, HHS Secretary Kathleen Sebelius was in the hot seat last week when senators quized herabout delays in vaccination production. For providers in Chicago, "The limitation right now is the vaccine supply. When they get it, they will use it as best they can", says Julie Morita, left, who is with the city health department's immunization program.

Molecular epidemiology of adenovirus type 4 infections in US military recruits in the postvaccination era (1997-2003)

BACKGROUND

Military recruits are at a higher risk of respiratory infection than their civilian counterparts. Continuous outbreaks of adenovirus (Ad)-associated acute respiratory disease were documented among US trainees before the implementation of serotype 4 (Ad4) and serotype 7 vaccines in 1971. The discontinuation of Ad vaccination programs in 1999 precipitated the reemergence of Ad in training sites, with Ad4 accounting for 98% of all diagnosed cases.

METHODS

A total of 724 Ad4 strains isolated from recruits presenting with febrile respiratory illness at 8 training sites nationwide between 1997 and 2003 were genome typed by restriction enzyme analysis.

RESULTS

Seven genome types were identified, all of which were distinct from the prototype Ad4p and the vaccine type 4p1. Results showed very different, and often stable, genome type distributions at different geographic sites, despite the homogeneity of the recruit source population.

CONCLUSIONS

The data support the hypothesis that reservoirs for Ad outbreaks are within recruit training sites or in their immediate environments, not in the incoming recruit population. Molecular characterization beyond serotype is critical to understanding the transmission dynamics of Ad infection in these unique susceptible populations and to the implementation of effective prevention approaches.

Antigen and vaccine banks: technical requirements and the role of the european antigen bank in emergency foot and mouth disease vaccination

Antigen and vaccine banks are stocks of immunogenic materials ready to be formulated into vaccines (bulk antigens) or ready to use (vaccines) in case of need by one or more of the parties of the bank. These stocks were primarily developed by foot and mouth disease [FMD] free European countries to control unexpected severe FMD episodes after the cessation of routine vaccination in the 1990s. For various reasons, including the lack of suitable antigens or of discriminatory tests to be used following emergency vaccination, such banks have so far not been developed to control other transboundary diseases, although over the last few years stocks of vaccines have been collected by the European Community to support control measures for bluetongue or classical swine fever. The FMD virus antigens in the banks are stored at ultra-low temperatures (usually -130 degrees C) to guarantee a shelf life of at least five years compared to a shelf-life of one to two years for vaccines stored at +4 degrees C. When concentrated, a 50 I volume of antigens can contain up to 15 million cattle doses as per the standard potency specifications in the OIE Manual of Diagnostic Tests and Vaccines for Terrestrial Animals. Selecting antigen/vaccine strains for storage in a bank and selecting the appropriate strain(s) to be used in the case of emergency vaccination is the responsibility of FMD disease experts. The paper discusses the role of serological testing for the detection of infected animals in a vaccinated population, which is necessary for the recognition of FMD status. Technical advantages and disadvantages of antigen and vaccine banks in general are also outlined in this article. Finally, the experience of the European Community in organising, renewing, and controlling a sizeable FMD antigen bank since 1993 is discussed, and the use of the European Union (EU) antigen bank for international actions outside the EU is presented.

[International health at home: bringing the experiences back home with you]

International Health research conducted under extreme conditions in low-income countries may lead to a better understanding of epidemics in high-income countries, by questioning assumptions which are important in these countries. Examples are given of how observations in Guinea-Bissau have led to reinterpretation of the decline in measles mortality, of the polio model, and of the impact of stopping vaccinations after eradication in the industrialised countries.

Varicella zoster virus vaccination policies and surveillance strategies in Europe

The incorporation of varicella zoster virus (ZVV) vaccination in childhood immunisation schedules is becoming an increasingly common option in Europe. The current study forms part of the European Sero-Epidemiology Network 2 (ESEN2) organisational analysis for VZV and describes current passive immunisation policies, as well as current and proposed active immunisation strategies, and existing surveillance systems for diseases caused by the varicella zoster virus in ESEN countries. A questionnaire was compiled and distributed to 23 participating countries. A VZV vaccine is currently licensed in 14 of the 20 participating ESEN countries. Germany is the only country to have incorporated VZV vaccination into its routine childhood immunisation programme. Three further countries currently recommend vaccination of children against VZV and five countries are also considering introducing routine immunisation against VZV for children. However, of the eight countries with or considering introducing childhood VZV immunisation, only six have case-based mandatory notification of varicella, and only two countries have primary care surveillance data available for herpes zoster.

The use of antigen and vaccine banks in case of emergency vaccination in the European community

The Community control measures for foot-and-mouth disease (FMD) have been reviewed and are currently laid down in Directive 2003/85/EC of 29 September 2003. The Community is free of FMD and infection without practising vaccination. Legal provisions are in place to resort to emergency vaccination where required by the epidemiological situation and reserves of suitable antigens of the FMD virus for express formulation into vaccines have been established.

Extending the foot-and-mouth disease module to the control of other diseases

During the recent devastating epidemics of foot-and-mouth disease (FMD), bluetongue (BT), the highly pathogenic avian influenza (HPAI) and New Castle disease, more than 115 million animals were culled. The mass slaughter of animals raised serious ethical questions. These epidemics showed that the use of emergency vaccination is an essential element in disease control. During the last decade the FMD antigen banks have proved to be effective and this module should be extended. An international vaccine stock should be considered for classical swine fever and HPAI. Agreements with vaccine producers should be made easily available, with instant access to a vaccine reserve for rinderpest, peste des petits ruminants, BT, African horse sickness and Rift valley fever. These vaccines should meet international standards and should allow distinction between vaccinated and infected animals. Information should be gathered proactively on the use of vaccines for lumpy skin disease, sheep and goat pox and contagious bovine pleuropneumonia.

Australian contingency plans for emergency animal disease control: the role of antigen/vaccine banks

Vaccination is an important element of contingency plans for many animal diseases. The decision whether or not to use vaccine is complex, and must consider epidemiological, economic and social issues. Vaccines are rarely available in a country for emergency animal diseases unless a low pathogenicity strain of the agent is present or it is localised in carrier hosts. High quality commercial vaccine from overseas is often the preferred source of vaccine in an emergency, although less reliable sources may be used with additional safeguards. Alternatively, master seeds may be imported or developed for production within the country For contingency planning, diseases may be ranked according to the expected role of vaccine in the disease eradication strategy, with diseases for which vaccine is part of the initial response strategy receiving highest priority for action. A range of preparedness options is available, ranging from identifying producers of vaccine, obtaining permits for import and use from regulatory authorities, to establishing vaccine or antigen banks. Countries need to consider their individual situations and develop strategies to address the diseases of significance to them.

A global virtual network for foot-and-mouth disease in case of emergency

The use of emergency vaccination is considered in different contingency national plans as part of a foot-and-mouth disease (FMD) control strategy in countries whether vaccination is practised or not. The development of the inter-governmental and national FMD vaccine and antigen banks and some technical and operational problems that could affect their efficiency are analysed. The possibility of improving and implementing a more rational use of the antigen and vaccine banks through the creation of a Global Virtual Network of Vaccine and Antigen Banks is discussed.

[Preventive vaccines against papillomavirus and cervix cancer will soon enter clinical practice]

A vaccine may protect against cancers caused by high-risk human papillomaviruses (HPVs). Sexually transmitted high-risk HPV types are almost always found in cervical cancer. Incidents of HPV type 16 and cervical cancer has more than doubled after the 1980's in Finland. HPV L1 capsid protein can be produced in the yeast, after which it assembles into virus-like-particles (VLP) and can be readily used for vaccine production. HPV VLP vaccine is well tolerated and induces ten-fold higher serum antibody levels as compared to natural infection. HPV16 VLP vaccine has shown to be 91% protective effect against HPV16 infections in the first phase III study. Neutralizing HPV antibodies, induced by HPV VLP vaccination, effectively reduce the viral load even though total elimination of the virus may not be needed. It is not known for how long the vaccine induced protection will last. Recruitment of adolescents into population-based phase III vaccination studies should be large to allow reliable cancer registry based evaluation of protective effect against grave dysplasia and cervical cancer.