New Approaches to the Prevention of Visceral Leishmaniasis: A Review of Recent Patents of Potential Candidates for a Chimeric Protein Vaccine.

The development of prophylactic vaccines is important in preventing and controlling diseases such as visceral leishmaniasis (VL), in addition to being an economic measure for public health. Despite the efforts to develop a vaccine against human VL caused by Leishmania infantum, none is available, and the focus has shifted to developing vaccines against canine visceral leishmaniasis (CVL). Currently, commercially available vaccines are targeted at CVL but are not effective. Different strategies have been applied in developing and improving vaccines, such as using chimeric proteins to expand vaccine coverage. The search for patents can be a way of tracking vaccines that have the potential to be marketed. In this context, the present work presents a summary of immunological aspects relevant to VL vaccine development with a focus on the composition of chimeric protein vaccines for CVL deposited in patent banks as an important approach for biotechnological development. The resulting data could facilitate the screening and selection of antigens to compose vaccine candidates with high performance against VL.

A Review of Major Patents on Potential Malaria Vaccine Targets.

Malaria is a parasitic infection that is a great public health concern and is responsible for high mortality rates worldwide. Different strategies have been employed to improve disease control, demonstrating the ineffectiveness of controlling vectors, and parasite resistance to antimalarial drugs requires the development of an effective preventive vaccine. There are countless challenges to the development of such a vaccine directly related to the parasite's complex life cycle. After more than four decades of basic research and clinical trials, the World Health Organization (WHO) has recommended the pre-erythrocytic Plasmodium falciparum (RTS, S) malaria vaccine for widespread use among children living in malaria-endemic areas. However, there is a consensus that major improvements are needed to develop a vaccine with a greater epidemiological impact in endemic areas. This review discusses novel strategies for malaria vaccine design taking the target stages within the parasite cycle into account. The design of the multi-component vaccine shows considerable potential, especially as it involves transmission-blocking vaccines (TBVs) that eliminate the parasite's replication towards sporozoite stage parasites during a blood meal of female anopheline mosquitoes. Significant improvements have been made but additional efforts to achieve an efficient vaccine are required to improve control measures. Different strategies have been employed, thus demonstrating the ineffectiveness in controlling vectors, and parasite resistance to antimalarial drugs requires the development of a preventive vaccine. Despite having a vaccine in an advanced stage of development, such as the RTS, S malaria vaccine, the search for an effective vaccine against malaria is far from over. This review discusses novel strategies for malaria vaccine design taking into account the target stages within the parasite's life cycle.

Vaccine approaches applied to controlling dog ticks.

Ticks are considered the most important vectors in veterinary medicine with a profound impact on animal health worldwide, as well as being key vectors of diseases affecting household pets. The leading strategy applied to dog tick control is the continued use of acaricides. However, this approach is not sustainable due to surging tick resistance, growing public concern over pesticide residues in food and in the environment, and the rising costs associated with their development. In contrast, tick vaccines are a cost-effective and environmentally friendly alternative against tick-borne diseases by controlling vector infestations and reducing pathogen transmission. These premises have encouraged researchers to develop an effective vaccine against ticks, with several proteins having been characterized and used in native, synthetic, and recombinant forms as antigens in immunizations. The growing interaction between domestic pets and people underscores the importance of developing new tick control measures that require effective screening platforms applied to vaccine development. However, as reviewed in this paper, very little progress has been made in controlling ectoparasite infestations in pets using the vaccine approach. The control of tick infestations and pathogen transmission could be obtained through immunization programs aimed at reducing the tick population and interfering in the pathogenic transmission that affects human and animal health on a global scale.