Hot Topics in Infection Prevention: Vaccines, Vaccines, Vaccines; Containing COVID-19 at Summer Camp; Ebola Outbreak

There’s been a lot of activity on the COVID-19 vaccine front thanks to research regarding waning immunity. A mix-and-match strategy seems to be emerging.

FDA and COVID-19 Vaccine Updates

The Food and Drug Administration just announced authorization for Moderna and Johnson & Johnson booster shots and the mix-and-match strategy in the wake of debates and research regarding waning immunity and the longevity of protection. “The Johnson & Johnson booster was authorized for anyone 18 and over—a broad eligibility criteria reflecting the lower protection of the initial single-shot regimen when compared with other coronavirus vaccines. The Moderna booster, a half-dose of the original shot, was authorized for people 65 and older, or adults at risk of severe illness or complications because of underlying medical conditions or exposure on the job.” Speaking of vaccines—CIDRAP reports that two new studies were just published that show pretty impressive efficacy of the vaccines against the Delta variant—upwards and over 90%.

Moreover, a new observational study in Israel from the Clalit Research Institute and a partnership with Harvard University, estimated a 93% efficacy of the Pfizer vaccine against symptomatic infection in teenagers. The authors noted that “The results show that in fully vaccinated adolescents (7 to 21 days after the second dose), the risk of symptomatic COVID-19 decreased by 93% compared with the unvaccinated, while the risk of documented infection decreased by 90%. In the period immediately preceding the second dose (days 14–20 after the first dose), vaccine effectiveness was lower, but still substantial—the risk of symptomatic COVID-19 decreased by 57% in vaccinated individuals, and the risk of documented infection by 59%.”

COVID-19 Lessons at Summer Camp

One of the more interesting studies that’s been released in recent weeks (and there are many) has been a Morbidity and Mortality Weekly Report from the Centers for Disease Control and Prevention regarding multicomponent strategies for prevention across several youth summer camps. This report was fascinating in that compliance can be tricky in these environments—long periods of time in cabins around others, physical activities, and thousands of individuals. In this report, they found that through screening, vaccination coverage, and other interventions, they could reduce transmission. The authors noted that “frequent testing was coupled with multiple prevention strategies, including podding, masking, physical distancing, and hand washing. A pod began as a group of campers and staff members who were in the same cabin. Pod residents were allowed to interact with each other without masking or physically distancing. Camps merged pods in stages, growing from one cabin to multiple cabins, to age groups. Each session required new campers and staff members to follow the same podding protocol. Three camps reached campwide pod expansion. The decision to end indoor masking at each pod expansion stage was predicated on all persons having a negative test result, unless state or local regulations prevented this (one camp). Staff members were permitted to remove masks when they were among other vaccinated staff members and separated from unvaccinated persons.” Understanding effective strategies for not only these environments, but also those for school-age children is a beneficial lesson in community and even hospital infection prevention.

Ebola Outbreak in DRC

More cases have been identified in the latest Ebola virus disease outbreak in eastern Democratic Republic of Congo (DRC). The World Health Organization (WHO) African Region just reported an update – noting 5 confirmed cases and three deaths. Currently, there are 386 contacts identified and 322 being monitored. Reuters reports: “Health officials have said the latest flare-up of the virus appeared to be linked to the massive 2018–20 outbreak, which killed more than 2200 people and infected more than 1000 others. The cases were detected on Saturday in the health district of Butsili, close to the city of Beni where the last outbreak was centered, the WHO said in a statement. Three people out of the five confirmed cases have died. This latest outbreak has continued to emphasize the need for survivor research and ongoing surveillance.””