Drug regulators in the Democratic Republic of Congo (DRC) have approved the emergency use of two mpox vaccines to help curb a surge in cases involving a novel clade 1 strain, Reuters reported today, based on documents and sources involved in the process.

The vaccines include Jynneos, made by Bavarian Nordic, and LC16, made by KM Biologics in Japan, where it is stockpiled for bioterrorism countermeasure purposes. Bavarian Nordic officials confirmed to Reuters that the DRC had approved emergency use, and a KM Biologics source told the news agency that there was potential supply of the vaccine.

Unlike countries battling the global clade 2 mpox, African counties have never had access to vaccines or treatments.  Gavi, the Vaccine Alliance, told Reuters that it is ready to facilitate vaccine donations from the United States and Japan. The group is unable to buy vaccine supplies for lower income countries until specific vaccines are prequalified by the World Health Organization (WHO).

In a recent update, the WHO said the clade 1 outbreak continues to expand in the DRC, with the first case recently detected in North Kivu province, pushing the number of affected provinces to 23 of 26. The virus is spreading through various forms of contact, including sexual and household.  

Nature has published a large study showing that text message reminders to receive a COVID-19 booster worked to increase vaccine uptake, but that offering free rides to pharmacies did not. 

The study was based on outcomes seen among 3.66 million CVS Pharmacy patients in the United States who were offered free round-trip Lyft rides via text to CVS Pharmacies for vaccination appointments and received seven different sets of behaviorally informed vaccine reminder messages. 

Though millions of Americans took the initial series of COVID-19 vaccines, subsequent booster doses have been less popular. In the fall of 2022 and 2023, less than 20% of Americans received bivalent boosters, the authors said.

"This raises the question of how COVID-19 booster vaccination can be increased," the authors said. "Although vaccine mandates are effective, they are not always popular or feasible, Moreover, in the United States, cash incentives for vaccination have proven surprisingly ineffective."

Text messages resulted in additional 30,000 vaccinations 

Text messages and removing transportation hurdles to vaccination appointments were two methods suggested as possible ways to increase booster uptake. The megastudy, conducted in the autumn of 2022, looked at multiple interventions to increase vaccine update, and relied on CVS vaccine records to account for vaccine update in the 30 days post-intervention. Free Lyft rides and a series of seven text messages, all meant to convey to patients that a vaccine was ‘recommended’ and ‘waiting for you,’ were tested. 

They found text messages increased the 30-day COVID-19 booster uptake by 21% (1.05 percentage points) and spilled over to increase 30-day influenza vaccinations by 8% (0.34 percentage points), resulting in additional 33,864 COVID-19 booster vaccinations and 10,756 flu vaccinations. But when the messages included the free Lyft ride offer, no increase in uptake from the baseline message was observed.

These extra vaccinations probably prevented an estimated 1,857 infections.

"Because COVID-19 booster vaccinations reduce infections by at least 43% compared with individuals who received their last monovalent COVID-19 dose at least 8 months before, these extra vaccinations probably prevented an estimated 1,857 infections," the authors concluded.  

Yesterday Moderna reported that its respiratory syncytial virus (RSV) vaccine, mResvia, showed only 50% efficacy in preventing the illness after 18 months. The results are disappointing compared to the 81% efficacy seen at 3.7 months. 

Moderna’s vaccine also underperformed compared to GlaxoSmithKlein’s vaccine, Arexvy, which was 68% effective over 23.3 months in a clinical trial. Trials have shown Pfizer's Abrysvo to be 78% effective after 16.4 months.

The drugmaker announced the findings late yesterday afternoon at a meeting of the Centers for Disease Control and Prevention's (CDC's) Advisory Committee on Immunization Practices (ACIP). 

Last month the Food and Drug Administration (FDA) approved the Moderna vaccine for use in older adults,  making it the second approved RSV vaccine for adults 60 years and older. ACIP currently recommends all US adults 75 and older receive a single RSV vaccine, and that people ages 60 to 74 also receive a dose of the vaccine.

According to the CDC, 60,000 to 160,000 older adults each year are hospitalized in the United States due to RSV. 

Currently the CDC and ACIP are weighing age recommendations for approved RSV vaccines given concerns about the risk of Guillain-Barre syndrome (GBS) following RSV vaccination.