Travel Vaccine Breaking News

A new study conducted in Las Vegas suggests that when testing for the SARS-CoV-2 coronavirus, the results may actually overestimate the virus's local health risks.

The findings from an Original Investigation suggest the continual influx of tourists in vacation destinations may distort clinical testing relevance.

While wastewater surveillance is a valuable complement to clinical tools and can provide time-sensitive data for decision-makers and policymakers, this study represents a novel approach to quantifying the confounding effects of mobile populations on wastewater surveillance data.

Furthermore, the detection of SARS-CoV-2 RNA in wastewater does not indicate infectivity, so while a significant viral load may be contributed by visitors (>60% in this study), this does not necessarily prove that visitors are a significant contributor to local COVID-19 transmission. 

Researchers from the University of Nevada collaborated with the Southern Nevada Water Authority on the study published by the JAMA Network Open on February 23, 2023.

Note: This study's conclusions may apply to other tourist destinations such as Paris, Miami, New York, London. and Tokyo.

In the United States, influenza activity began earlier than usual this season, increasing in October 2022. However, influenza infections have steadily diminished since a peak in late December 2022.

According to a Morbidity and Mortality Weekly Report (MMWR) published today by the U.S. CDC, Influenza A(H3N2) represented most of the viruses detected and subtyped during this period.

The best news is that this virus is the same genetic subclade as and antigenically similar to the viruses included in the 2022–23 Northern Hemisphere influenza vaccine.

This is important since the effectiveness of seasonal flu shots varies by season, as influenza virus subtype and antigenic match with circulating viruses.

This MMWR interim report used data from two concurrent studies conducted in Wisconsin from October 23, 2022–February 10, 2023, to estimate influenza vaccine effectiveness (VE).

Overall, VE was 54% against medically attended outpatient acute respiratory illness associated with laboratory-confirmed influenza A among patients aged six months–64 years.

In a community cohort of children and adolescents aged <18, VE was 71% against symptomatic laboratory-confirmed influenza A virus infection.

Furthermore, these interim analyses indicate that influenza vaccination substantially reduced the risk for medically attended influenza among persons aged <65 years and for symptomatic influenza in children and adolescents.

The CDC says 'annual influenza vaccination is the best strategy for preventing influenza and its complications, and recommends that health care providers continue administering it to persons aged ≥6 months as long as influenza viruses are circulating.

As of February 24, 2023, various flu shots remain available at pharmacies throughout the U.S.

Moreover, most flu shots are offered at no cost to the person.

The U.S. Centers for Disease Control and Prevention (CDC) vaccine advisory committee today presented an overview of a successful childhood vaccination program.

Mona Marin, M.D., with the CDC Advisory Committee on Immunization Practices, presented '25 Years of Varicella Vaccination Program in the United States: Health and Economic Impact during 1995–2019' on February 23, 2023.

Historically, varicella was considered a disease of little consequence, too mild to warrant prevention.

However, Varicella is an illness with a characteristic maculopapular, vesicular rash.

During the pre-vaccine era, varicella infected almost everyone during childhood, who accounted for more than 90% of the cases, two-thirds of the hospitalizations, and about half of the deaths, wrote researchers in a related article.

Varicella, known as chickenpox, is also highly infectious, with 61% and 100% secondary attack rates among susceptible household contacts, says the CDC.

As other causes of infectious disease burden in children in the U.S. were controlled through vaccination (e.g., measles, diphtheria, poliomyelitis), varicella assumed more importance as a preventable cause of mortality and morbidity.

Based on a documented continuing disease, the U.S. was the first country to implement a routine varicella vaccination program following the licensure of the live, attenuated varicella vaccine (VARIVAX®, Merck & Co, Inc) in 1995.

Expansion of the U.S. vaccination program to include a second VARIVAX dose led to further declines in disease incidence, outbreaks, hospitalizations, and deaths.

Twenty-five years after the introduction of the varicella vaccine, the disease has declined overall by about 97%.

An additional benefit of the varicella vaccination program is the impact on HZ.

Recent data show a lower HZ risk among healthy and immunocompromised children. This is reflected in stepwise declines in HZ incidence at the population level as the age groups became dominated by persons born during the varicella vaccination program.

Moreover, the decline in HZ incidence in children provides tentative reassurance that, over time, HZ rates will decline as vaccinated children age.

The Journal of Infectious Diseases published the unedited article in November 2022.

Note: Varivax and the HZ-prevention vaccines (Shingrix) are generally available at clinics and pharmacies in the U.S.

Gilead Sciences, Inc. today announced data evaluating lenacapavir in combination with broadly neutralizing antibodies (bNAbs) teropavimab and zinlirvimab as a potential long-acting HIV treatment regimen with twice-yearly dosing.

Results from the Phase 1b clinical trial demonstrated the investigational combination was generally well tolerated with high efficacy in select virologically suppressed participants living with HIV.

At Week 26, 90% of participants receiving the complete study regimen (n=18/20) maintained virologic suppression (HIV-1 RNA ≤50 copies/mL). 

“Novel long-acting HIV treatment options will drive the next chapter in care and may help meet the therapy needs and preferences of people living with HIV. In this study, we found that lenacapavir and bNAbs in a combination approach may have a significant role to play in the future treatment of HIV,” said Dr. Joseph Eron, MD, lead study investigator and the Chief of the Division of Infectious Diseases at the University of North Carolina School of Medicine, in a press release on February 21, 2023.

“As a clinician who strives to support the people living with the virus under my care, it will be exciting to continue evaluating the combination regimen as a potential twice-yearly long-acting HIV treatment option.”

The combination of lenacapavir with teropavimab and zinlirvimab will advance to a Phase 2 study later in 2023 in virologically suppressed people living with HIV.

Lenacapavir is being developed as a foundation for future HIV therapies to offer long-acting oral and injectable options with several dosing frequencies, combined with other antiretroviral agents for treatment or as monotherapy for prevention, that help address individual patient needs and preferences.

Sunlenca® (lenacapavir), alone or in combination, is not approved by any regulatory authority outside the United States, United Kingdom, Canada, or the European Union for any use.

Note: bNAbs are not preventive vaccines. Furthermore, the U.S. FDA has not approved any HIV vaccine candidate.

LinKinVax today announced the interim results of a double-blind, Phase I clinical trial evaluating CD40.HIVRI.Env, a preventive HIV vaccine candidate.

The ANRS VRI06 study's initial results, published on February 22, 2023, show that the vaccine candidate was safe and induced an early, significant, and sustained immune response.

The vaccine yielded high levels of antibodies directed against the HIV envelope: 

• 80-100% at Week 6,
• 100% at Week 26 in all groups (0.3, 1, and 3 mg).
• These levels remained stable or dropped slightly until Week 48.
• Antibodies targeting a specific area of the HIV envelope (V1/V2 region) were also produced.

Furthermore, at Week 26, neutralizing antibodies were detected in 50% of subjects in the 0.3 mg group and 100% of subjects in the other two groups.

The observed counts of CD4+ T cells targeting specifically the HIV envelope protein produced after the vaccination remained stable until Week 48.

Prof. Yves Lévy, Executive Director of the Vaccine Research Institute and CMSO of LinKinVax, commented in a press release, "The immune response profile generated by this vaccine (antibody response and activation of polyfunctional CD4+ T cells) was the one associated with a reduced risk of HIV infection in the RV144 trial."

"However.... the efficacy of this vaccine will only be evaluated in the Phase II/III studies."

LinKinVax's vaccine platform is built around a humanized monoclonal antibody, which is merged with regions of pathogens of interest, targeting the CD40 molecule expressed by dendritic cells, DC, which play a key role in stimulating the immune system. 

André-Jacques Auberton-Hervé, Co-founder and CEO of LinKinVax, added, "We are pleased with these very promising immunogenicity results, which demonstrate the robustness of our DC Targeting vaccine platform and confirm its safety."

"This important milestone paves the way for the upcoming Phase II/III clinical studies that we will conduct once the final Phase I results has been obtained."

"These studies will aim to demonstrate the efficacy of the vaccine, the "Everest of vaccine strategies," which has been the elusive goal of HIV research for the past 40 years."

Other HIV vaccine development news is posted at Precision Vaccinations.

Vaxcyte, Inc. announced today that the U.S. Food and Drug Administration (FDA) had cleared the Company's infant Investigational New Drug (IND) application for VAX-24, its lead, 24-valent pneumococcal conjugate vaccine (PCV) candidate designed to prevent invasive pneumococcal disease (IPD).

Vaxcyte stated it plans to initiate the infant Phase 2 study in the second quarter of 2023, with data expected by 2025.

The infant study design will include a primary immunization series consisting of three doses followed by a subsequent booster dose.

"The clearance of the VAX-24 infant IND application marks an important step in expanding the development of our lead, broad-spectrum PCV candidate in this important and vulnerable population," said Grant Pickering, Chief Executive Officer and Co-founder of Vaxcyte, in a press release on February 21, 2023.

"Based on the positive data from our Phase 1/2 proof-of-concept study in adults, we believe VAX-24 has the potential to deliver a best-in-class profile with broader coverage and better immune responses relative to the standard-of-care for both the adult and pediatric populations."

"We remain focused on advancing our VAX-24 clinical programs and look forward to the anticipated initiation of the infant study and announcement of the topline results from our Phase 2 study in adults aged 65 and older in the second quarter of this year."

Despite the effectiveness of current vaccines, IPD, which includes meningitis and bacteremia, remains persistent in the first years of life and is a leading cause of invasive disease in children two years of age and under.

The burden of disease in the pediatric population underscores the need for a broader-spectrum vaccine.

Precision Vaccinations post additional pneumococcal disease vaccine and candidates news.