Vaccine News

The Pan American Health Organization (PAHO) says countries in the Region of the Americas need to ensure that yellow fever vaccination coverage is uniformly greater than or equal to 95% to curtail future outbreaks.

Unfortunately, 33 confirmed cases of yellow fever, including 17 deaths, have been reported in the Americas throughout 2024. These cases have been reported in five countries in the Region of the Americas: the Plurinational State of Bolivia, Brazil, Colombia, Guyana, and Peru. 

The PAHO confirmed on July 29, 2024, that these countries need to ensure that health authorities maintain routine vaccination and, at the same time, respond to possible outbreaks, such as in Columbia's mountain region.

Eight confirmed cases of yellow fever, including five deaths, have been reported in Columbia this year. One case had a history of vaccination against yellow fever.

From a local perspective, the Secretary of Health of Huila, Colombia, issued a Red Alert for rising numbers of confirmed yellow fever cases on August 2, 2024.

The U.S. Embassy says travelers planning to travel to this area of Colombia are encouraged to talk to their medical provider about proper precautions against this mosquito transmission and to prevent infection, such as vaccination.

As of August 2024, approved yellow fever vaccines are offered in various countries. In the United States, the YF-Vax vaccine is available at certified travel clinics and pharmacies.

The U.S. CDC recommends yellow fever vaccination for persons over nine months traveling to or living in areas of South America and Africa at risk of yellow fever. Because serious adverse events occur, clinicians should vaccinate only persons at risk for exposure to the yellow fever virus or require proof of vaccination for country entry.

To eradicate polio, the Global Polio Eradication Initiative brings together the latest scientific knowledge on this vaccine-preventable disease. In late July 2024, the GPEI launched Team End Polio, a new campaign to unite fans everywhere around a common goal: to end polio for good.

Team End Polio is bringing together a world-class roster of athletes, global leaders, and advocates to raise awareness for polio eradication online and on the field.

This effect is essential since the risk of the emergence of a circulating vaccine-derived poliovirus type 1 (cVDPV1), Wild poliovirus type 1 (WPV1), or circulating vaccine-derived poliovirus type 3 (cVDPV3) has increased due to low vaccination coverage.

The GPEI also tracks the status of the poliovirus spreading every week. During the week of July 31, 2024, the following poliovirus reports were confirmed:

Pakistan: 11 WPV1-positive environmental samples

Chad: one cVDPV2 case and one positive environmental sample

Guinea: one cVDPV2 case

Liberia: two cVDPV2 positive environmental samples

Niger: three cVDPV2 positive environmental samples

Nigeria: six cVDPV2 cases and three positive environmental samples

Palestinian Territory: six cVDPV2 positive environmental samples

Sierra Leone: one cVDPV2 positive environmental sample

Yemen: one cVDPV2 case

The U.S. CDC's latest Travel Health Advisory says that before visiting any of 34 destinations, adults who have previously completed the full, routine polio vaccine series may receive a single, lifetime booster dose of the polio vaccine. Polio vaccines are offered at health clinics and pharmacies in the U.S.

The results of the PrEPVacc HIV vaccine trial conducted in Africa between 2020 and 2024 show conclusively that neither of the two experimental vaccine regimens tested reduced HIV infections among the study population.

The PrEPVacc vaccine trial results, announced at AIDS 2024 in Germany in July 2024, report more infections in the two vaccine arms than in the placebo arms. Still, the researchers say they cannot draw a definitive conclusion about this because the statistical ‘confidence intervals’ for the comparison are so wide, indicating high uncertainty.

PrEPVacc tested two different combinations of HIV vaccines.

One regimen combined a DNA vaccine (DNA-HIV-PT123) with a protein vaccine (AIDSVAX B/E), and the other combined the same DNA vaccine, a modified non-dividing virus vector (MVA-CMDR), and a protein-based vaccine (CN54gp140).

The vaccination schedule included four vaccine injection visits: three over approximately six months and a fourth a year after enrolment. 

The PrEPVacc trial was stopped in November 2023 when it became clear to independent experts monitoring the study data that there was little or no chance of the vaccines demonstrating efficacy in preventing HIV acquisition.

Dr Peter Gilbert, Principal Investigator, who is independent of the PrEPVacc study and has no ties with it, commented in a press release on July 23, 2024, “Given the PrEPVacc results that the estimated rates of HIV-1 acquisition were higher in the vaccine arms than the placebo arm, it is important to thoroughly quantify and communicate the precision available for drawing inferences about whether the vaccines truly elevated risk or, alternatively, a statistical fluke occurred and the vaccines were indeed safe."

"P-values are incomplete tools for this task because they cannot be interpreted in terms of the question, ‘What is the chance the vaccine elevated the acquisition rate?’

“To fill this gap, I conducted a Bayesian analysis that provides answers to this desired interpretation, using the same method that I previously applied to other HIV vaccine efficacy trials."

"The result was that, for each vaccine, there is close to a 50-50 chance that the vaccine elevated acquisition risk vs. the vaccine was safe, as a synthesis of results over multiple ways to do the analysis, most importantly considering different prior distributions for vaccine efficacy," added Dr. Gilbert.

As of August 2, 2024, the U.S. FDA has approved an HIV vaccine.

Although immunization can dramatically reduce the mortality and morbidity associated with vaccine-preventable diseases, uptake remains suboptimal worldwide.

A systematic review and meta-analysis of strategies to promote vaccination uptake was recently published in Nature Human Behaviour. The review analyzed the results of 88 eligible randomized-controlled trials testing interventions from 17 countries.

Published on August 1, 2024, the researchers considered seven vaccine intervention strategies: increasing access to vaccination, sending vaccination reminders, providing incentives (e.g., money), supplying information, correcting misinformation, promoting active and passive motivation, and teaching behavioral skills.

“Public health officials often say that ensuring vaccine access is the first step to promoting immunization,” said co-author Dolores Albarracín, the Amy Gutmann Penn Integrates Knowledge University Professor at the University of Pennsylvania, in a press release.

“Our meta-analysis provides hard evidence supporting this recommendation and indicates that this should be a priority in under-resourced areas with limited access to health care.

Interventions to increase access to vaccines included offering transportation assistance or bringing vaccines to recipients at sites like nursing homes, family homes, and workplaces.

There was also a small effect of promoting financial incentives for healthcare providers.

For example, a U.S. study achieved an 85% influenza vaccination rate when physicians were reimbursed $1.60 per dose, compared with a 70% vaccination rate when they were reimbursed $0.80 per dose.

However, the effects of incentives were quite small in both this U.S. study and the estimates from the meta-analysis.

GSK plc today announced that its market-leading herpes zoster vaccine, Shingrix®, produced £0.8 billion in sales during the second quarter of 2024, which is 4% less than the previous period.

On July 31, 2024, GSK revealed that Shingrix sales did increase YTD.

In the United States, sales in the quarter decreased by 36% at AER and CER, reflecting channel inventory reductions and changes in retail vaccine prioritization in part due to a transition to a new CMS rule that changed how pharmacies process reimbursements from payers.

In addition, lower demand in the U.S. was driven by challenges activating harder-to-reach consumers, which remains a priority.

At the end of Q1 2024, the cumulative immunization penetration rate reached 37% of the more than 120 million adults currently recommended by the U.S. CDC to receive Shingrix.

Internationally, Shingrix sales grew significantly in the quarter and YTD.

Markets outside the U.S. now represent 64% of Q2 2024 global sales (Q2 2023: 46%), with Shingrix launched in 45 countries. The majority of these markets have average cumulative immunization rates below 5%

This increase was driven by a national immunization program in Australia, regional funding in Japan, and supply to co-promotion partners in China, despite phasing some expected sales into Q3.

In Europe, Shingrix grew in the quarter and YTD from expanded public funding, partly offset by declining demand in Germany.

Shingles is a painful skin rash caused by reactivation of the varicella-zoster virus, which causes chickenpox, says the U.S. CDC. If you've had chickenpox, you are at risk for shingles. This long-lasting pain is called postherpetic neuralgia (PHN), the most common complication of shingles.

The CDC says the risk of getting shingles and PHN increases as people age.

Merck today announced financial results for the second quarter of 2024 were $16.1 Billion, an increase of 7% from the same period in 2023.

In the cancer prevention market segment, Merck's Human papillomavirus (HPV) vaccines reported sales increases. 

The 4% growth in the GARDSAIL/GARDASIl 9 HPV vaccines was primarily due to higher sales in the U.S., driven by higher pricing, demand, public-sector buying patterns, and higher demand in certain ex-U.S. markets.

The growth was largely offset by lower sales in China due to the timing of shipments compared with the prior year.

“Our business is demonstrating strong momentum as we exit the first half of the year,” said Robert M. Davis, chairman and chief executive officer of Merck, in a press release on July 30, 2024.

“Through excellent scientific, commercial, and operational execution, we’re achieving significant milestones for our company and patients, including the launch of WINREVAIR. I am proud of our dedicated teams around the world that are working tirelessly to advance our deep pipeline as we continue delivering innovation that solves unmet medical needs.”

According to the U.S. CDC, there is an increasing rate of STDs. For example, people 55 and older reported a significant increase in HPV diagnoses.

'Almost every unvaccinated person who is sexually active will get HPV at some time in their life. About 13 million Americans, including teens, become infected with HPV each year. Most HPV infections will go away on their own. But infections that don’t go away can cause certain types of cancer.'

Merck's HPV vaccines are generally available at medical clinics and pharmacies in the United States.

A clinical trial due to launch in the Democratic Republic of Congo (DRC) and other African countries will assess whether a mpox vaccine can protect people against the disease after they have come into contact with the virus. 

As of July 29, 2024, the phase 4 clinical trial (#NCT05745987) has received US $4.9 million to see if Bavarian Nordic’s MVA-BN® (JYNNEOS®, IMVAMUNE®, IMVANEX®)) mpox vaccine could reduce the risk of secondary mpox cases, or if a person contracts mpox, it could reduce the severity of illness.

CEPI stated in a press release that the evidence generated could be crucial in shaping mpox vaccination strategies to help tackle a significant and deadly mpox outbreak escalating in the DRC and neighboring countries. Over 11,000 cases and 443 deaths have been reported in the DRC in 2024, with children accounting for the majority of infections and deaths.

Mpox was first identified in the DRC in 1970. The mpox virus strain behind the current outbreak is known as Clade I. Spread through direct contact, and it is estimated to be fatal in around 8-12% of cases.

Health experts have also noted concern for a strain known as Clade Ib that is fast-spreading in eastern DRC regions, including Kamituga, South Kivu. This mpox strain appears to be spread through both sexual transmission and skin-to-skin contact.

In the United States, the JYNNEOS vaccine was approved for smallpox prevention in 2019 and has been readily available for mpox since May 2022. As the number of mpox cases dwindled in 2024, vaccinations decreased.