Vaccines 2025

In 2021, amidst the peak of the global COVID-19 vaccination campaign, a rare safety signal emerged that captured the attention of the medical community. Researchers from Israel and the United States were the first to identify and report a correlation between mRNA vaccines (Pfizer-BioNTech and Moderna) and the onset of myocarditis, particularly in young males. A new study conducted at Stanford Medicine offers the first detailed molecular explanation for this phenomenon. According to the study's findings, in the rare instances where myocarditis occurs, the vaccine triggers a specific inflammatory cascade.

The vaccine advisory committee of the U.S. CDC (Centers for Disease Control and Prevention) has voted to revoke the universal recommendation requiring the vaccination of all newborns against Hepatitis B at birth. This decision is sparking widespread uproar among pediatricians. What do we know about the Hepatitis B vaccine? Baruch Blumberg, a Jewish physician, identified an antibody in a hemophilia patient in New York in 1964. Due to multiple blood transfusions, this patient had been exposed to a wide variety of antigens. Blumberg found that this antibody reacted against a protein previously identified in an individual on the other side of the world - an Australian Aborigine. He named the antigen the Australia Antigen (AuAg). It was later discovered that this antigen is part of the Hepatitis B virus. Today, this antigen, which constitutes the viral envelope, is known as HBsAg (Hepatitis B Surface Antigen).

VacPertagen (BioNet) is a next generation pertussis vaccine designed to overcome the immunological shortcomings of current acellular formulations. The platform integrates two refined recombinant antigens: pertussis toxin (PTgen) and filamentous haemagglutinin (FHA). Both antigens are produced through precision molecular engineering. The genes encoding PT and FHA are cloned into high yield expression systems, typically using plasmid vectors introduced into cultured production cells. These cells express the proteins in a controlled environment that allows accurate folding, stabilization of key conformational epitopes, and removal of reactogenic elements. The recombinant proteins are then purified with chromatographic methods that isolate structurally intact antigenic domains while eliminating residual cellular material. This process ensures reproducible antigen quality, consistent molecular composition, and enhanced presentation of the immunologically relevant epitopes.

A new study found that cell-based influenza vaccines may offer superior seasonal flu prevention, providing approximately 20% greater protection than standard egg-based vaccines during the 2023/24 season. The research analyzed data from more than 100,000 vaccinated individuals across multiple age groups and risk categories. CSL Seqirus, the manufacturer behind the study, reported that its cell-based vaccine demonstrated a consistent advantage in both pediatric and adult populations, regardless of underlying health status. These findings indicate a clear clinical benefit of cell-based vaccines over conventional egg-based formulations.

A large cross-sectional study published in JAMA Pediatrics evaluated the long-term impact of HPV vaccination over 17 years in adolescent girls and young women, many at elevated risk for HPV infection. The findings demonstrate both high population-level effectiveness and clear herd protection.

The Centers for Disease Control and Prevention (CDC) vaccine advisory group has revised its recommendations regarding the combined measles, mumps, rubella, and varicella (MMRV) vaccine for the youngest children. The decision aligns with ongoing efforts by Health and Human Services (HHS) Secretary Robert F. Kennedy Jr. to reassess childhood vaccination policies and schedules. The change is driven by evidence of an elevated risk of febrile seizures, seizures triggered by fever, when the combined vaccine is administered as the first dose in children under four years of age.

Australia has approved, for the first time, a unique vaccine against chlamydia in koalas (Phascolarctos cinereus). The bacterium Chlamydia pecorum causes severe disease in koalas, manifesting as blindness, infertility, urinary tract damage, and even death. In some regions, infection rates reach 50–70%. The aim of the vaccine is to protect wild koala populations, requiring an extensive operation of capture, vaccination, and ongoing monitoring. It is a single-dose vaccine that had previously been tested in koalas at rehabilitation and rescue centers. The product is a recombinant subunit vaccine based on the outer membrane proteins of the bacterium, combined with an adjuvant to enhance the immune response.

On September 3, 2025, Florida’s Deputy Health Secretary announced that the state aims to abolish all mandatory vaccinations for children in public schools, including immunizations against measles, chickenpox, polio, diphtheria, tetanus, vaccines that by law are regarded as essential. The initiative is backed by Governor Ron DeSantis, who belongs to a political current emphasizing individual rights and medical freedom. This move continues a trend that began with the appointment of Kennedy as Health Secretary and undermines fundamental structures of the American, and even global, healthcare system. Health authorities across the state and the United States have voiced strong opposition, warning of the risks involved. This controversial initiative unfolds in the midst of a measles outbreak in the U.S., the most significant surge in cases in three decades.

According to the ECDC report, from the beginning of 2025 until July, approximately 240,000 cases of Chikungunya and about 90 deaths were recorded across 16 countries and territories. Chikungunya is a viral disease caused by the Chikungunya virus (CHIKV), a member of the Togaviridae family, genus Alphavirus. The virus is transmitted to humans through bites of Aedes mosquitoes. These mosquitoes are daytime feeders, which increases the risk of transmission.

On April 9, 2025, GC Biopharma announced that the Korean Ministry of Food and Drug Safety (MFDS) approved BARYTHRAX, the world’s first recombinant anthrax vaccine. Co-developed with the Korea Disease Control and Prevention Agency (KDCA), the vaccine targets Bacillus anthracis, the bacterium responsible for anthrax, classified as a Class 1 infectious disease* due to its high lethality and potential use as a biological weapon.

At its first meeting in its new composition, the U.S. Advisory Committee on Immunization Practices (ACIP) recommended that influenza vaccines be administered only in formulations that do not contain the mercury-based preservative, thimerosal. The appointment of Kennedy as U.S. Secretary of Health has shaken the American healthcare system, with its effects rippling across international health organizations. Prominent officials have been dismissed or resigned abruptly. These developments inevitably impact major public health topics. What is Thimerosal?

Poliomyelitis (polio), caused by the poliovirus, remains a key target for global eradication as part of international initiatives led by the World Health Organization (WHO), UNICEF, and the Global Polio Eradication Initiative (GPEI). As of 2025, only two endemic regions remain where local transmission of wild poliovirus type 1 (WPV1) is still reported: Pakistan and Afghanistan. Vaccination programs in these countries primarily rely on the oral live-attenuated poliovirus vaccine (OPV). However, the attenuated virus in the vaccine can undergo genetic changes and regain virulence, potentially causing disease - a phenomenon known as circulating Vaccine-Derived Poliovirus (cVDPV).

Health Secretary Robert F. Kennedy Jr. has dismissed the entire Advisory Committee on Immunization Practices (ACIP), comprising 17 members. This expert panel advises the Centers for Disease Control and Prevention (CDC) on immunization matters. The ACIP, which convenes three times annually, plays a critical role in evaluating vaccine data and formulating usage recommendations. The committee consists of 15 voting members - physicians, epidemiologists, and public health experts representing a wide range of disciplines including clinical practice, vaccine research, behavioral science, community health, and geriatric medicine - as well as ex-officio federal liaisons and non-voting representatives from various agencies and stakeholder organizations.

A study published in Emerging Infectious Diseases investigated the potential cross-protection conferred by seasonal quadrivalent influenza vaccines (QIVs) against highly pathogenic avian influenza A(H5N1) viruses, specifically those of clade 2.3.4.4b. Despite initial expectations, the study found limited evidence that QIVs elicit significant neutralizing antibody responses against these H5N1 strains in humans, particularly within the examined cohort of primarily healthy adults. The immunity induced by seasonal vaccination appears insufficient to confer robust or durable protection against severe H5N1 disease.

Respiratory Syncytial Virus (RSV) is the leading cause of hospitalization among U.S. infants, particularly those aged 0–2 months. Maternal RSV vaccination and nirsevimab (a long-acting monoclonal antibody) administration were introduced during the 2023–2024 U.S. RSV season. A study published in MMWR assessed the association between the availability of these interventions and RSV-associated hospitalizations by comparing pediatric hospitalization rates from RSV-NET and NVSN during the 2024–2025 season with those from the 2018–2020 pre–COVID-19 seasons.

What are Dr. Vinay Prasad’s views on vaccines? Dr. Vinay Prasad, a hematologist-oncologist and professor at UCSF, was appointed director of the FDA’s Center for Biologics Evaluation and Research (CBER), overseeing vaccine regulation. While he recognizes COVID-19 vaccines as life-saving, he has publicly criticized several related policies.

The U.S. Department of Health and Human Services has announced that all new vaccines will be required to undergo placebo-controlled trials prior to receiving licensure. Traditionally, modern vaccine trials have compared investigational vaccines to existing licensed vaccines rather than to placebos, primarily due to ethical considerations. When an effective vaccine already exists for a given disease, the use of a placebo in clinical trials would entail withholding proven protection, thereby exposing participants to unnecessary risk. This practice contravenes the ethical principle of non-maleficence, which obligates researchers to minimize harm.

Scientists from Sydney have discovered that administering a booster dose in the same arm as the initial vaccination can elicit a faster and more effective immune response. Published in Cell, their findings provide new insights that could inform future vaccination strategies. The researchers found that after vaccination, macrophages in nearby lymph nodes undergo "priming," preparing them to guide memory B cells for a more rapid and robust response if the booster is delivered to the same site. Previous work showed that memory B cells - critical for mounting antibody responses upon reinfection -tend to reside in the lymph node closest to the original injection.

The Advisory Committee on Immunization Practices (ACIP) in the United States recently recommended administering a vaccine against Respiratory Syncytial Virus (RSV) to individuals aged 50–59 who are in high-risk groups. This is in addition to the existing recommendations for vaccinating individuals aged 75 and older, as well as adults aged 60–74 who are at increased risk. RSV belongs to the family Paramyxoviridae and is one of the most common causes of respiratory tract and lung infections worldwide, particularly during the winter months. The virus causes a range of respiratory infections across all age groups but is particularly dangerous in infants and older adults.

Uganda has launched a malaria vaccination campaign in Apac District, northern Uganda. This makes Uganda the 19th country in Africa to introduce the malaria vaccine into routine immunisation, and it marks the largest malaria vaccine roll-out to date in terms of target districts and population. The R21/Matrix-M malaria vaccine, administered in four doses at 6, 7, 8, and 18 months, will initially target 1.1 million children under two years of age in 105 high- and moderate-transmission districts across Uganda, with plans for nationwide expansion.

The ASFV-G-ΔI177L vaccine is a modified-live African swine fever virus (ASFV) strain developed as a vaccination measure against African swine fever (ASF) in pigs. This vaccine strain was created by partially deleting the I177L gene and replacing it with the mCherry reporter gene. The ASFV-G-ΔI177L strain has been incorporated into a commercially available vaccine, used to immunize pigs, particularly via intramuscular or oronasal routes. It has shown promise in protecting commercial pigs against ASFV infection. However, concerns regarding its genetic stability emerged following studies indicating that ASFV-G-ΔI177L could revert to virulence during in vivo passaging. Reversion was associated with ASF-specific clinical signs and increased viremia in infected pigs, raising concerns about its safety and effectiveness as a vaccine.

A new report published in MMWR found that between 2008 and 2022, cervical precancer incidence decreased by 79%, and higher-grade precancer incidence decreased by 80% among screened women aged 20–24 years - the age group most likely to have been vaccinated. Human papillomavirus (HPV) causes approximately 10,800 cervical cancers annually in the United States, making cervical cancer the most common HPV-attributable cancer among women. Between 2008 and 2022, a total of 39,977 cases of cervical precancer were reported in the U.S.

COVID-19 vaccines provided significant protection and prevented millions of deaths. However, in a small number of individuals, the vaccines may have led to a range of side effects, including fatigue, myalgia, brain fog, tinnitus, and dizziness, collectively referred to as 'post-vaccination syndrome,' according to a new small-scale study conducted by scientists at Yale University.

Texas health authorities recently reported an unusual measles outbreak with 90 confirmed cases (as of February 21), the majority occurring in children and adolescents. Most cases have been reported in Gaines County. Sixteen patients have been hospitalized, and most affected individuals are under the age of 18. This is the most severe measles outbreak in Texas in approximately 30 years. Four of the infected individuals were vaccinated, while the remainder were not. A study published in 2021 in Scientific Reports analyzed the rise in measles cases in the United States in the post-elimination era (the U.S. declared measles eliminated in 2000), covering the period from 2001 to 2019.

The controversial appointment of Robert F. Kennedy as Secretary of Health in the new Trump administration undoubtedly raises concerns about the "future" of vaccines and immunization rates within the population. Moreover, this appointment provides momentum to various anti-vaccination movements.