As a scientific organization rooted in evidence-based research, 91Â鶹ÌìÃÀ strongly supports the universal application of vaccines to prevent illness and death caused by infectious diseases. Despite overwhelming successes, including the eradication of smallpox, many people have questions or misconceptions about how vaccines work. Explore the science behind vaccines and learn more about what 91Â鶹ÌìÃÀ is doing to support vaccine equity and research policy.
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Whole-Pathogen Vaccines | Viral Vectors | Subunit Vaccine | Nucleic Acids | |||||||
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ATTENUATED | INACTIVATED | REPLICATING | NON-REPLICATING | PROTEIN SUBUNIT | POLYSACCHARIDE / CONJUGATE | TOXOID | VIRUS-LIKE PARTICLES | RNA | DNA | |
Living pathogen that has been weakened (but not killed) in the laboratory | Whole pathogen killed by heat, chemicals or radiation | A carrier virus that is able to infect human cells (such as an adenovirus) is introduced carrying genetic material that codes for the specific viral antigen in order to elicit the immune response. | A carrier virus (such as an adenovirus) that is able to infect human cells but cannot replicate is introduced carrying genetic material that codes for the specific viral antigen in order to elicit the immune response. | Purified viral antigens | Surface polysaccharide antigens, primarily from bacterial pathogens | Chemically inactivated toxins from pathogen | Particles that contain virus surface proteins that can elicit an immune response, but lack viral genetic material (so cannot replicate) | mRNA injected directly into muscle tissue and translated into specific pathogen protein antigens by host cellular machinery. | Plasmid containing pathogen DNA that encodes for specific antigens, injected directly into cellular tissue. | |
MMR vaccine | Polio vaccine, Rabies vaccine, Typhoid vaccine | Animal vaccines such as for Rift Valley fever virus, avian influenza | Animal vaccines such as for Rift Valley fever virus, avian influenza | Candidate Zika vaccine | Candidate vaccines for SARS, Bird flu (H5N1, H1N1), Zika | Diphtheria vaccine, Tetanus vaccine | Human papillomavirus vaccine | Candidate Zika vaccine | Candidate vaccines for SARS, Bird flu (H5N1, H1N1), Zika | |
Elicits strong immune response | Contains actual pathogen so will direct proper immune response | Efficient delivery of genetic material into host cells and tissues | Efficient delivery of genetic material into host cells and tissues | No chance of infection by pathogen | No chance of infection by pathogen | Raise direct immune response to pathogenic component | Easy access into cells | Directs the expression of viral antigens without threat of viral infection or need for integration into host DNA | Directs the expression of viral antigens without threat of viral infection | |
Slight potential for microbe reactivation | May require an adjuvant to stimulate complete immune response | May be suppressed by existing host immune response | May be suppressed by existing host immune response | Requires efficient delivery mechanism that protects against degradation | May require an adjuvant to stimulate complete immune response | May require an adjuvant to stimulate complete immune response | May be suppressed by existing host immune response | Difficult delivery into cells | Difficult delivery into cells |
Disease Specific Expertise
Thanks to federal investments in basic and clinical research, the development and effective use of vaccines for a broad range of life-threatening illnesses has saved countless lives in our nation and around the world.
COVID-19: Kizzmekia Corbett, Ph.D., of the NIH's COVID-19 Response Team discusses her role in the development and testing of a spike-encoding mRNA vaccine for coronavirus.
Dengue: Stephen Thomas, M.D., explores the latest research on the mosquito-borne illness dengue and dengue vaccine development.
Fungal disease: The rise of antifungal resistance has made treatment of fungal diseases increasingly difficult. Scientists are exploring tactics for generating vaccines against common fungal pathogens.
Human immunodeficiency virus: Dan Barouch, M.D., Ph.D., lays out the unique challenges of developing an HIV vaccine and discusses the ongoing clinical trial with an adenovirus-based vaccine developed in his lab.
Human papillomavirus: Doug Lowy, M.D., explains how research of bovine papillomavirus led to the development of an HPV vaccine.
Influenza: There are now several "universal" flu vaccine candidates in clinical trials that aim to provide broader and longer-lasting influenza protection.​
Malaria: Malaria is one of humanity’s oldest foes. What will it take to defeat it? New vaccines, coupled with other preventive tactics, will be key.
Measles: Measles and similar epidemics can arise in populations even where most people have been vaccinated, in part, due to a false sense the disease has been eliminated. Addressing misconceptions is the first step to ammending this.
Mpox: Reeti Khare, Ph.D., answers questions about the mpox (formerly called monkeypox) outbreak and how the smallpox vaccine can offer partial protection against the virus.Pertussis: Unlike other childhood vaccine preventable diseases, the number of cases of pertussis have increased since the 1980s. The reasons for this increase are complex.
Plague: A new mRNA vaccine protects mice from the infection by Yersinia pestis, the bacterium that causes plague. What do the findings mean for the development of antibacterial mRNA vaccines?
Polio: Both the inactivated polio vaccine and oral polio vaccines have been instrumental in polio control efforts but have limitations that scientists are working to overcome.
Tick-borne disease: TWiM discusses an mRNA vaccine that induces antibodies against tick proteins and prevents transmission of the Lyme disease agent, Borrelia burgdorferi.
Yellow Fever: Derick Kimathi, Ph.D., is investigating the safety and efficacy of using smaller doses of yellow fever vaccine to induce similar immunologic protection as standard dose.
Communicating About Vaccines
Vaccine hesitancy—the reluctance or refusal to vaccinate despite the availability of vaccines—threatens to reverse progress made in tackling vaccine-preventable diseases. In 2019, the World Health Organization declared vaccine hesitancy 1 of the 10 biggest threats to global health.
Vaccine Hesitancy
​Vaccines Are Critical. Here’s How You Can Help Spread the Word:
Many are not skeptical of vaccines because of science, but due to a wide variety of reasons—and therefore science alone does not always change minds. Learn how to spread the word about the value of vaccines and combat misinformation.
Vaccine Equity
COVID-19 Vaccinations in Underrepresented Communities: While there are many barriers—from the historical burdens of underrepresented populations to accessibility and affordability of care—there are also tangible approaches to help make healthcare more equitable for all.
91Â鶹ÌìÃÀ Calls for Equity in Vaccine Distribution: 91Â鶹ÌìÃÀ advocates for supplemental funding to CDC for vaccines, testing, contact tracing and mitigation to underserved communities and communities of color to ensure equity in pandemic response.
Paul Offit joins TWiV to discuss all things vaccine, including how COVID-19 vaccine development was accelerated, whether the vaccines are safe and efficacious, the difference between an EUA and a licensed vaccine, sterilizing immunity, herd immunity and much more.