The likelihood of covid-19, the disease caused by the new coronavirus, resulting in a pandemic is increasing. The virus associated with this disease has now been detected in 40 countries. In recent days, the World Health Organization has been talking about a closing window for containing the situation. As the outbreak expands, most countries, including the United States, will have to switch from containment to mitigation as a priority.

The point of mitigation, as opposed to containment, is to reduce the effect of the outbreak rather than eliminating the virus. Our leaders need to be honest about what that probably means in practical terms: the prospect of widespread infection in communities across the country.

Political and public health leaders have the instinct to keep the public calm, but incorrect reassurances can undermine public trust when it is needed the most. (Just look at Tuesday, when President Trump declared that the virus was “very well under control in our country,” mere hours before the Centers for Disease Control and Prevention said it was “inevitable” that it would spread in the United States.) Being candid about the potential of widespread transmission of a virus is likely to increase concern, but at this point, the benefits of a better-prepared public outweigh the downside of increased worries.

One way of tamping down the unwanted side effects of increased anxiety and fear is to increase the sense that the general public can do something to reduce the likelihood of infection. It is important to communicate that we are not passive, helpless witnesses to an unfolding mass event: We have the ability to reduce personal and community risk of this contagion. We can reduce risk by regularly washing our hands, not going to work or school if we are sick, and getting the flu shot to reduce overcrowding at health-care facilities during the outbreak. Talking about these and other evidence-based approaches could decrease the sense of helplessness.

Protective public health tactics could include reducing mass gatherings, dismissing students from schools or closing them altogether for a while, and implementing “social distancing” measures. These public health interventions have consequences for the livelihood and the well-being of the population. Making sure these interventions are implemented based on emerging evidence and with consideration of the rights of those affected is essential to a humane and effective public health response.

While the so-called nonpharmaceutical interventions — i.e., protective public health measures that do not involve drugs or vaccines — can be helpful in reducing the effect of a large outbreak, effective and long-term control of this virus will probably also require mass vaccination.

It took approximately two years to develop a vaccine for SARS, and by the time the vaccine was available for initial human trials, the outbreak was over. For the current outbreak, at least 39 vaccine development programs are already underway. This early progress is due to advances in technology since previous large outbreaks.

For example, the technology for identifying vaccine targets on the virus is more advanced than it was even when SARS broke out. Because of genetic similarities between covid-19 and SARS, as well as advances in technologies for decoding viral genetic information, scientists were able to quickly create a genetic sequence useful for developing vaccines. Similarly, technological innovations such as using “messenger” RNA as a vaccine has sped up initial development of vaccines. (Production is still at least a year away.)

But the biggest barrier to vaccine availability is not biological. It is what happens after a biological product is developed and tested in animals. Conducting human trials is an essential step in determining the efficacy and safety of vaccines before deploying them in the general population.

The market for a vaccine against something like covid-19 is hard to predict, because it’s inherently difficult to forecast how the virus will spread and where. That means there is very little incentive for large vaccine manufacturers to invest in such vaccines; they don’t have a good sense of how or when their investment will pay off. Therefore, a few years ago, scientists and public health professionals created a global public-private partnership called the Coalition for Epidemic Preparedness Innovations (CEPI). This organization aims to speed up the development of vaccines against emerging infectious diseases and make them quickly accessible to people during outbreaks.

CEPI has already given out four contracts for development and human testing of covid-19 vaccines. However, the resources available to CEPI are substantially lower than the challenge it faces — and far lower than what private pharmaceutical companies could spend. In 2009, the overall budget for CEPI was $187 million; in the same year, the vaccine R&D budget for just one company, Sanofi Pasteur, was approximately $600 million.

CEPI’s funders include the governments of Norway, the United Kingdom, Germany, Japan, Canada, Ethiopia, Australia and Belgium; the Bill & Melinda Gates Foundation; and the Wellcome Trust. One entity is conspicuous by its absence from this list: the United States government. While the U.S. has vaccine programs based at and facilitated by domestic entities such as the National Institutes of Health, the global nature of large outbreaks require multicountry vaccine development programs. As Congress considers new funding for responding to the coronavirus outbreak, it should consider allocating money for CEPI to accelerate its vaccine development and testing efforts.

The covid-19 outbreak is already a multicountry emergency. CDC’s characterization that it is inevitable the virus will spread widely in the United States may very well be true. But the impact can be reduced based on how we and our leaders react. It depends on how our leaders communicate the ever-changing risk, whether disease-control measures follow science, how much we comply with the public health measures, and whether we treat each other with dignity and compassion. After all, we are not passive, helpless observers.

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