President Trump initially kept reasonable travel restrictions to prevent the spread of the coronavirus, but with the virus spreading inside the United States, he is already shifting from minimizing its threat — his first instinct — to use it to justify restrictive immigration policies that he wanted anyway. A broader move to general nativism at this time would be disastrous, as so many immigrants are leading the U.S. response to the virus.

A new analysis of government data from the Cato Institute shows that eight of the major companies developing treatments and vaccines for the virus are heavily reliant on foreign workers. From 2010 to 2019, we found that the Department of Labor approved the companies developing treatments or vaccines for coronavirus to hire more than 11,000 immigrants and H‑1B high skilled foreign workers.

Pharmaceutical companies rely on foreign workers

Among these hires were 3,310 foreign biochemists, biophysicists, chemists, and other scientists on H‑1B visas. They had brought in thousands of statisticians to analyze data and software, database, and computer engineers to support them. Without these workers, America’s hope of treating and saving thousands of lives at risk from the coronavirus would greatly diminish.

Gilead Sciences, for example, has developed a leading candidate to treat the disease, which is in ongoing clinical trials. It received approvals for more than 300 biochemists, biophysicists, and other biological scientists last year alone. Sanofi, which is working with the U.S. government’s Biomedical Advanced Research and Development Authority on a vaccine, relies on dozens of H‑1B workers on its research team. Sanofi even hired its chief medical officer on an H‑1B visa in 2010.

Moderna Therapeutics, which has the first vaccine to reach Phase 1 trials in the United States, obtained H‑1B approvals for 18 biological technicians, biochemists, biophysicists or biomedical engineers in 2019 alone.

This shouldn’t be a surprise. We’ve known for years that many of the top drug researchers in America are foreign-born. A 2013 report from the Partnership for a New American Economy found that at the top 10-patent producing U.S. universities, 79 percent of drug or drug compound patents had a foreign-born inventor. In molecular biology and microbiology the share was 75 percent.

It’s not just the researchers America needs either. We also need doctors, nurses, and home health aides—all occupations where immigrants are disproportionately represented. In New York City where the coronavirus outbreak is shutting down schools, 45 percent of doctors and 58 percent of registered nurses were foreign-born in 2016. Among home health care aids who are particularly important for the elderly population most at risk from the virus, the share was 76%.

These immigrants are the first responders to this crisis. America must treat them as heroes, not as threats.

Not all “prevention techniques” are equally effective

The United States needs to be careful in its response to the virus. The Centers for Disease Control states that Americans, especially older Americans, shouldn’t unnecessarily travel. The government has already adopted reasonable restrictions on foreign entries, but a broader assault on immigration that targets skilled immigrants would reduce America’s effective response to coronavirus.

America’s skilled medical and research professionals are already hampered by this administration. Researchers of Chinese ethnicity in the United States are being punished for collaborations in China at a time when America needs more collaboration on important research targeting the coronavirus.

Simultaneously, the U.S. government is dramatically escalating the number of denials for H‑1B visas for skilled workers—increasing from 6 percent to 32 percent from 2015 to 2019, according to a new report by the National Foundation for American Policy.

As Congress prepares a legislative response to the crisis, it should consider completely exempting all pharmaceutical researchers and scientists as well as doctors and physicians from the H‑1B and green card limits and expediting their processing. It should specifically enact legislation to permit in more foreign doctors to underserved areas—particularly in rural areas.

A medical crisis is not the time to talk about stopping all legal immigrants. It’s the time for more legal skilled immigrants to help fight this virus.