An Outsized Contribution in Qatar

In the global scientific effort to understand vaccine and natural immunity to SARS-CoV-2, Weill Cornell Medicine’s location in Qatar, a country of only a few million people, has been making an outsized contribution. A team led by Dr. Laith Abu-Raddad, professor of population health sciences, has been publishing one high-impact study after another, revealing real-world vaccine effectiveness against all the main variants of the virus — from alpha to omicron — as well as the significance of natural immunity due to prior infection. Their work has appeared in the New England Journal of Medicine, JAMA, Lancet and Nature Medicine, among others.

In a headline-making study last June, for example, the team evaluated the effectiveness of the Pfizer and Moderna mRNA vaccines during the first Omicron-variant wave in Qatar in the winter of 2021–22. The researchers found, as expected, that full vaccination and booster, plus a history of infection during an earlier wave, was associated with the greatest level of protection during the Omicron wave — about 75 percent. However, the results also underscored a growing concern in the public health community by showing that the original mRNA vaccines’ effectiveness in preventing symptomatic Omicron infection disappeared within six months. By contrast, earlier-wave infection was associated with significant protection from Omicron lasting over a year.

The WCM-Qatar team had run numerous influential epidemiology studies in the Middle East, on infectious and age-related diseases, in the years before the pandemic. When it became clear in early 2020 that SARS-CoV-2 was going global, the researchers sprang into action, working with Qatar’s Ministry of Public Health to forecast health care needs and craft policies.

One advantage of the Emirates’ compact size — Qatar is smaller than Connecticut — is that its health care and health records are highly centralized. The researchers, at the outset of the pandemic, crucially helped structure Qatar’s COVID-19 record-keeping system to make it easier for them to track the new virus’s spread and the effectiveness of vaccines.

“We ended up with comprehensive, centralized databases that include everything related to SARS-CoV-2 and COVID-19 — all testing, hospitalizations, and, later on, vaccinations,” said team member Dr. Hiam Chemaitelly, assistant professor of research in population health sciences.

It helped, too, that Qatar’s population had a rapid uptake of the vaccines when they became available. (The country by now has administered more than 7 million doses — more than two per resident).

By now, going on three years since the pandemic started, the team has produced dozens of COVID-19 studies using their countrywide, comprehensive health records database. And team members are not slowing down — they are currently studying the latest, highly contagious and vaccine-evading Omicron subvariants.

“The rapid waning of vaccine immunity and the rapid evolution of SARS-CoV-2 suggest that we will continue to have infection waves,” Dr. Abu-Raddad said. “So our work is far from over.”