The Efficacy and Effectiveness of Vaccines in Reducing Infection, Severity, Hospitalization, and Mortality
We largely owe most of today’s convenience and comfort in life to the notable advancements human beings have made in various fields. The medical developments have been particularly fruitful, having saved millions of lives through different mediums, including vaccines. A massive decrease in the rates of deaths caused by infections compared to the past is the most pivotal outcome of the development of vaccines. The likes of measles, hepatitis B, pneumonia, and other diseases whose names are used to give people a chill to the bones are no more a threat as long as one does not skip the relevant vaccines and sticks to the immunization plans. Everyone must get vaccinated, from the youngest to the oldest, and that is not merely a personal choice but a social responsibility, as future generations will reap benefits as well.
Introduction
Vaccines have shown an admirable performance in preventing the spread of infectious diseases and decreasing their severity to a great degree. However, vaccines are most functional against VPDs or vaccine-preventable diseases. These diseases are caused by bacteria or viruses and can be highly contagious, but as the name suggests, the medical community has tamed them via vaccines. These diseases are no longer a death threat since many people have developed protective antibodies through the use of vaccines. They include COVID-19, influenza (flu), polio, hepatitis A, B, and E, diphtheria, typhoid, pneumococcal infections, meningococcal infections, tetanus, Ebola virus disease, measles, mumps, rubella, human papillomavirus (HPV), varicella (chickenpox), Haemophilus influenzae type b, and pertussis. That said, VPDs keep involving many people around the globe; for instance, the CDC (Centers for Disease Control and Prevention) suggests reports of VPD infections for more than thousands of people only in the United States. This is while immunization equity is always facing numerous challenges, and there needs to be more efforts to bring about healthier environments in some developing countries. In any case, the world has become much safer with regard to a considerable number of infectious diseases, thanks to highly efficient and effective vaccines available.
Efficacy Vs. Effectiveness
Unlike what the public might assume, vaccine efficacy is not the same as its effectiveness. Efficacy comes before effectiveness and is a critical criterion for a vaccine to gain approval according to federal regulations. The clinical trial consists of two stages. First, two groups of volunteers of different characteristics – including sex, medical conditions, age, and ethnicity – either get vaccinated or receive a placebo. The next stage is to observe the influence on the test subjects and, subsequently, compare the number of sick people in each group. In a nutshell, and as a way of explanation, an efficacy of 60% means that the vaccinated group has been under a lower risk of infection in the 60% range. On the other hand, effectiveness deals with the performance of a vaccine in the real world. Despite the fact that the vaccine is approved or not, the effectiveness might meet the expectations or miss the mark. Miscellaneous circumstances may precipitate unexpected out-turns when the vaccine is put to use on a broader scale. Therefore, time is the key to having a more in-depth understanding and more reliable account of the effectiveness of a particular vaccine, since long-term immunity does not take shape immediately.
Active vs. Passive Immunity
It is worth mentioning two types of immunity in order to understand the function of vaccines along the immunization progress. Active immunity is the result of the process in which the body lives through exposure to an antigen — a weakened virus or a dead one. Through this process, which may take days or weeks, the body shows an immune response and produces antibodies. Vaccination falls into this category. On the other hand, passive immunity derives from the direct delivery of ready-made antibodies and offers short-term protection in exchange for its immediacy. Natural passive immunity occurs when such antibodies are transferred to the baby through the placenta. What is more, some people feel the urge to try out products, such as Immune Globulin which contains antibodies, in order to achieve immediate protection. All in all, whether you actually get infected (natural immunity) or trick your body into producing antibodies via vaccination (vaccine-induced immunity), active immunity is put in prior to passive immunity since it lasts longer and is sometimes life-long.
Variants of Viruses
One plain fact about viruses is their course of mutation, which may or may not end up in subsequent variants. In short, variants are mutated versions of a particular virus. They carry a slightly different viral genetic sequence which imparts functional changes in disease severity and transmissibility. Moreover, viral diagnostic tests may no longer be able to detect the variants, and they might cut through the aforementioned natural or vaccine-induced immunity to make it worse. That is why some viruses, such as influenza, remain a threat since a new variant spreads out each year, and people, especially the sensitive groups, should consider them in their immunization schedules.
Various Types of Vaccine Technologies
Different methods can be utilized to develop effective vaccines depending on the nature of the bacteria or the virus. The first type of vaccine which promises a robust immune response is live-attenuated vaccines, or simply live vaccines. As one of the earliest methods of vaccine production, taking advantage of a weakened bacteria or virus (pathogen) can provoke the urge for the immune system to produce the essential antibodies. Chickenpox, mumps, and measles are some of the frequently-used live vaccines. In contrast, inactivated vaccines contain dead/inactivated pathogens, such as influenza and polio vaccines. Though additional doses might be required, inactivated vaccines do not usually cost a fortune. In another similar type called subunit vaccines, the same method is deployed with the difference of using just a part of a pathogen and not the whole of it, which makes them appropriate choices for sensitive groups. Conjugate or polysaccharide vaccines, along with protein-based vaccines, belong to this category. Examples include pneumococcal, hepatitis B, Haemophilus, and acellular pertussis vaccines. Two more types are also available called viral vector and toxoid vaccines; the former provides the body with the genetic materials of the pertinent antigen via a different harmless virus (such as the Ebola vaccine), whereas the latter employs a totally different approach and carries a chemical or a toxin produced by the pertinent virus or bacteria. In this way, and contrary to the other vaccine types, the body is not triggered to get immunized against the infection but its effects.
Biosimilars: A Flourishing Alternative with Lower Prices
The mRNA (messenger RNA) vaccine shares a similar grounding with the vector-based vaccine, eliminating the virus from the immunization process and using a proxy (usually a protein) to convey genetic information of a virus to the body instead. Consequently, the triggered immune response will result in the production of antibodies. This, however, is not all of the stories about mRNA vaccines. Through the technology of biosimilars, we come to encounter a win-win situation, where the production rate is high with lower expenses at the same time. They have grown rapidly in recent years and keep flourishing as the more favorable alternatives to traditional biologic vaccines. Not only are they non-infectious and, thus, a preferable choice for people with weak immune systems, but they are also popular in developing countries. In line with the expanding demand for biosimilar products, the leading companies putting a substantial focus into this field to take over the market are manifold. One of the pioneering companies that have dedicated the majority of its plans to biosimilars is Opal Biopharma (OBP). OBP maintains cutting-edge technologies and an R&D center so as to offer quality products while keeping costs reasonable.
Final Thoughts
There is no better way than vaccination to avoid any vaccine-preventable disease. Even though some viruses undergo fundamental mutations and may cripple vaccines’ workability, it is necessary to keep your immunization plan up-to-date by getting follow-up recommended vaccines. There are six different technologies to develop vaccines, and the most recent mRNA type has begun to take the place of the rest. That is largely due to a relatively shorter manufacturing process (12-18 months) and a more reasonable final price. All in all, vaccines are safe as they will not get the green light without a series of rigorous clinical trials. A vaccine’s efficacy measure is a crucial factor for its validity; expectedly, higher efficacy rates will bring about higher effectiveness.
