Interview, Podcast
The Delta Variant: Implications for Vaccines, Booster Shots and Economic Growth
- The Delta variant is projected to drive a rapid case wave due to higher transmissibility and shorter exposure times, with single-dose efficacy dropping to approximately 30% and double-dose protection against symptomatic infection declining to around 40%, though protection against severe disease and hospitalization remains robust at 90%.
- Messenger RNA vaccines are expected to outperform adenoviral vaccines against symptomatic Delta infection, while breakthrough infections remain rare; when they occur, illness duration is anticipated to be two days shorter and flu-like symptoms 60% lower, with U.S. data through July showing roughly 6,600 hospitalized or deceased breakthrough cases among 160 million fully vaccinated individuals.
- Booster shots are planned for high-risk groups in countries like Israel, Germany, and France, with the CDC expected to update U.S. guidance by late summer or early fall, while Pfizer aims to file for an EUA in August and models assume annual boosting for the elderly and biennial boosting for younger adults.
- Companies are preparing regulatory pathways for next-generation variant-specific vaccines, with Pfizer initiating trials for a Delta-specific booster, while global manufacturing capacity is forecast to expand through 2022 and longer-term efforts are underway for multivalent combination shots pairing COVID-19 and seasonal flu vaccines.
- European case trends are expected to peak or decline in Spain, Portugal, and the Netherlands following the UK's trajectory, whereas cases are projected to continue rising in France and Italy while Germany maintains low levels.
- The Delta variant is anticipated to moderately weigh on U.S. growth through consumer risk aversion, leading to a slowdown in second-half consumption growth with annualized forecasts reduced by two percentage points due to a sluggish recovery in the consumer services sector and a delayed return to offices.
- U.S. growth is forecast to decelerate from approximately 7% this summer to a pace of 1.5% to 2% in the second half of next year, driven by a fiscal impulse turning negative in the back half of next year and office-adjacent economies remaining below full utilization for the foreseeable future.
- Global growth forecasts for the current year are expected to converge toward consensus levels, narrowing the gap from one percentage point to three-tenths, supported by global inventory replenishment, though this timeline may extend if Asian supply constraints persist.
- The U.S. unemployment rate is projected to fall from 5.9% to the low 4% this year, assisted by the expiration of federal benefits and rising vaccination rates, though a slower labor market recovery could constrain growth if complex barriers prevent returning to work.
- The primary downside risk to global growth is the emergence of a new, more transmissible variant that sharply reduces vaccine efficacy against hospitalizations, while eventual fading of U.S. labor market recovery and supply-side constraints is expected over time.