Vaccine News

Over the years, Ontario's measles cases have been rare, owing to the high immunization coverage. However, that favorable situation has changed in Canada's most populous province.

This new report from the public health ministry describes the epidemiology of measles in Ontario, focusing on the current multi-jurisdictional measles outbreak.

As of March 26, 2025, 557 measles cases (464 confirmed, 93 probable) had been reported in Ontario since October 28, 2024.

This is a significant change from the past decade.

Between 2013 and 2023, 101 confirmed measles cases were reported in Ontario, while 64 cases were reported in 2024.

Just to the south in the United States, Minnesota, Michigan, Ohio, Pennsylvania, and New York have also reported measles cases, but on a far reduced scale.

In 2025, a total 483 confirmed measles cases were reported by 20 U.S. jurisdictions.

As of March 30, 2025, the U.S. Centers for Disease Control and Prevention maintains a global measles outbreak Watch-Level 1, Notice, which does not include Canada.

The CDC recommends that most people get two doses of the MMR vaccine to protect against this infectious disease. Measles vaccines are generally available at travel clinics and pharmacies in the U.S.

According to the Global Polio Eradication Initiative (GPEI), several countries reported new circulating vaccine-derived poliovirus type 2 (cVDPV2) cases.

Nigeria reported three cases as of March 26, 2025, with onset dates in January and February, bringing its total for 2025 to ten instances. Last year, 98 cVDPV2 cases were reported.

Angola recorded its first case of 2025.

Additionally, GPEI reported that wastewater surveillance in Israel detected a positive cVDPV2 sample collected in the Central province. Genetic analysis indicates that this virus is not related to recent environmental detections in Europe or Gaza, but is most closely linked to a strain that originated in Nigeria's Zamfara state.

Israel is conducting a thorough field investigation to strengthen disease surveillance (including for acute flaccid paralysis cases in health facilities) and identify any residual subnational immunity gaps in this densely populated area.

And in Pakistan, one of two countries in which polio is still endemic, 24 Wild Polio 1-positive environmental samples were recently collected.

The total number of WPV1 cases in 2025 is six. Last year, Pakistan reported 24 WPV1 cases.

As of March 29, 2025, the U.S. CDC recommends international travelers speak with a travel vaccine expert before visiting any polio-risk area.

According to recent data from Japan's public health institute, the number of infectious gastroenteritis cases caused by norovirus and other pathogens in Japan has reached the highest level in ten years.

As of mid-March 2025, there were 34,609 norovirus cases reported by the National Institute of Infectious Diseases.

According to Japan's Ministry of Health, Labor and Welfare, most reported cases of infectious gastroenteritis are viral, primarily affecting infants and school-age children.

Like "infectious diarrhea" in Western terminology, norovirus is classified as a causative pathogen and a foodborne infection.

Historically, norovirus cases in Japan are detected in early winter, peak in December due to viruses like RSV, have a smaller peak in spring associated with rotavirus, and continue into early summer.

Bacterial infections, such as Vibrio parahaemolyticus, are more common in summer.

In summary, the Ministry says these infections can be categorized as sporadic or epidemic diseases in the region or as part of foodborne infectious diseases.

The U.S. CDC says norovirus is the leading cause of vomiting and diarrhea from acute gastroenteritis and stomach inflammation among people of all ages in the U.S.

Norovirus causes 58% of foodborne illnesses acquired, resulting in about 900 deaths, mostly among adults aged 65 and older, each year.

Furthermore, the CDC has reported 12 norovirus outbreaks on cruise ships. In 2024, 18 norovirus outbreaks were confirmed on U.S.-based cruises. 

As of March 28, 2025, the U.S. government has not approved a norovirus vaccine for commercial use.

Tuberculosis (TB) is the leading cause of death from a single infectious agent worldwide, including in England.

The UK Health Security Agency (UKHSA) report announced on March 24, 2025, reveals that TB remains a significant public health concern in England.

Data indicates that reported TB notifications increased by 13% in 2024, from 4,850 to 5,480 people, compared with 2023.

The most significant geographic increases were in London and the West Midlands

The UKHSA writes, ' If this rate of increase persists, the UK risks losing its WHO low incidence status of 10 cases per 100,000 population.'

According to the UKHSA, there is a strong association between the increase in TB incidence and the rise in migration, with about 81% of all notifications in 2023 coming from people born outside the UK. Work is underway to identify the optimal and most cost-effective control and prevention strategies to tackle this increase.

One tactic to reduce TB cases in children listed by the UKHSA is to optimize the use of Bacillus Calmette–Guérin (BCG) vaccines provision through commissioning and specification to include vaccinating infants at four weeks of age. While about 50% effective, BCG vaccination is an inexpensive defence against treating TB cases.

The global average cost for BCG vaccination is about $5.00. According to USAID, treating a tuberculosis case in the U.S. costs about $20,000, and a drug-resistant tuberculosis case can cost over $150,000.

As sexually transmitted diseases continue to spread in 2025, a new vaccine candidate may reduce the number of chlamydia cases in the United States. Current programs to prevent infection rates from rising have proven insufficient, highlighting the urgent public health need for a vaccine.

Sanofi announced today that the U.S. Food and Drug Administration has granted a fast-track designation to Sanofi's mRNA vaccine candidate for preventing chlamydia infection. 

The chlamydia vaccine candidate has been designed to protect against primary genital tract infection and reinfection by the bacterium Chlamydia trachomatis.

In 2020, there were 129 million worldwide cases of chlamydia among adults and adolescents, with the highest rates of infection among younger people.

Jean-François Toussaint, Global Head of Vaccines R&D, stated in a press release on March 26, 2025, "Millions of people currently live with undiagnosed chlamydia, including asymptomatic infection that can also cause severe long-term health effects if left untreated."

"Antibiotics to treat chlamydia have not been successful in controlling rising infection rates. With our program, we aim to make chlamydia a preventable disease through vaccination."

Following a promising preclinical program, Sanofi is planning a phase 1/2 randomized clinical study to evaluate the immunogenicity and safety of the chlamydia vaccine candidate in adults aged 18 to 29.

This clinical study is due to start in the coming days.

Chlamydia, caused by the bacterium Chlamydia trachomatis, is a common bacterial infection of the reproductive tract with consequences for developing infertility and pregnancy complications.

Although chlamydia can be treated with antibiotics when diagnosed, over 80% of chlamydia cases are asymptomatic, meaning there is a significant risk that infections go unrecognized, leading to untreated cases and unintentional transmission.

A study published by the Annals of Family Medicine on March 24, 2025, indicates that many women are not receiving guideline-adherent treatment in primary care settings. For example, the time to treat chlamydia was longer for patients aged 50-59 years (time ratio relative to those aged 20-29 years = 1.61; 95% CI, 1.12-2.30).

The development of this vaccine candidate is part of the Translational Science Hub, a partnership with the Queensland Government, Griffith University, and the University of Queensland that connects world-class researchers in Queensland, Australia, with Sanofi scientists in France and the U.S.

As of late March 2025, the FDA, the United Kingdom, and the European Medicines Agency have not approved a vaccine to prevent chlamydia infections.

Without a preventive vaccine available in the United States, an innovative treatment for uncomplicated urinary tract infections (uUTIs) has been approved.

New treatments are needed as the number of uUTIs caused by drug-resistant bacteria has increased, which can result in higher treatment failure rates.

GSK plc today announced that the U.S. Food and Drug Administration (FDA) has approved Blujepa, a first-in-class oral antibiotic with a novel mechanism of action that is GSK's infectious diseases portfolio.

Blujepa is approved for the treatment of female adults (≥40 kg) and paediatric patients (≥12 years, ≥40 kilograms) with uUTIs caused by Escherichia coli, Klebsiella pneumoniae, Citrobacter freundii complex, Staphylococcus saprophyticus, and Enterococcus faecalis.

GSK's Chief Scientific Officer, Tony Wood, commented in a press release on March 25, 2025, "The approval of Blujepa is a crucial milestone with uUTIs among the most common infections in women. 

"We are proud to have developed Blujepa, the first in a new class of oral antibiotics for uUTIs in nearly three decades."

uUTIs are the most common infection in women, impacting up to 16 million women in the U.S. annually.

Over half of all women are affected by uUTI in their lifetime, with approximately 30% suffering from at least one recurrent episode, which can cause significant patient burden, including discomfort and restriction of daily activities.

Two other products have been approved for use.

Pivya™ (Pivmecillinam) is an extended-spectrum penicillin antibiotic. Pivya targets penicillin-binding protein-2 in the cell wall of gram-negative bacteria, and has been available in Europe.

ORLYNVAH™ is a U.S. FDA-approved novel oral penem antibiotic for treating uUTIs caused by the designated microorganisms Escherichia coli, Klebsiella pneumoniae, or Proteus mirabilis in adult women.

While an oral UTI vaccine is available in several countries in 2025, Uromune™ (MV140) is unavailable in the U.S.

However, international travelers can request a vaccine appointment using this Vax-Before-Travel link.

While this respiratory disease is generally related to camel interactions in the Kingdom of Saudi Arabia, clinical efforts to produce a Middle East Respiratory Syndrome (MERS) vaccine have been elusive.

Since April 2012 and as of mid-March 2025, six World Health Organization regions have reported 2,618 cases of MERS, including 945 deaths, a significant case-fatality rate.

To address this need, CEPI announced, on March 25, 2025, a $2.6 million investment in moving a promising vaccine candidate into preclinical trials.

This new investment, developed by Newark, DE-based Uvax Bio, an early-stage vaccine technology company spun out of The Scripps Research Institute, is based on proprietary protein nanoparticle technology, 1c-SApNP®, licensed from Scripps Research.

The technology is already being tested against other infectious diseases, including HIV, where an in-human trial is ongoing.

Dr. Kent Kester, Executive Director of Vaccine R&D, CEPI, commented in a press release, “Uvax Bio’s unique vaccine could help strengthen our response to future MERS outbreaks while informing us of the vaccines being developed against other coronaviruses.”

Uvax’s novel vaccine design uses tiny protein “nanoparticles” to closely resemble or mimic the size and shape of the MERS coronavirus.

Uvax Bio has analyzed viral structures and designed the technology to present enhanced antigens —parts of the virus that trigger an immune response—in a multilayered scaffold layout. This design offers stability and allows for as many as twenty antigens to be presented at once, which could help provide strong protection by generating both antibody and T-cell immunity.

The 1c-SApNP® technology is also unique as it has been combined with a process called ‘glycan trimming.’

Here, sugar molecules—called glycans—that would generally cover the MERS virus are shortened in the nanoparticle virus-mimicking vaccine design. This could expose additional sites on the antigen surface, enhancing the immune response.

In addition to the vaccine candidate, several MERS vaccines are in clinical development addressing this zoonotic disease with an unknown source in 2025.