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.