America’s most-respected public health guru, Dr Anthony Fauci, said Wednesday that he is “cautiously optimistic’ that at least one COVID-19 vaccine will prove to be safe and effective later this month or next.

While warning that “one can never guarantee a safe and effective vaccine… we are cautiously optimistic that we will have one based on preliminary encouraging data,” said Fauci, director of the National Institute of Allergy and Infectious Diseases, speaking at a session of the weeklong  51st Union World Conference on Lung Health.

“We project that by November and December, we’ll have the answer, and then by the end of the year in the beginning of 2021 will be able to distribute doses of vaccines that have been pre ordered and made – prior to even knowing they would work.”

Priority for distribution of the first vaccine doses that are approved should go to healthcare workers and those with underlying conditions, he emphasized.

Fauci spoke at a World Conference panel on “the Hope for a Vaccine”; the panel also featured speakers from the World Health Organization, the Geneva Graduate Institute and the Barcelona Institue of Global Health.

In his review of both infection and research developments in the United States, Fauci, noted that the US government has been supporting the development and rollout of six vaccine candidates, with the US government investing billions of dollars in clinical trials and production plans.

Three separate platforms are being tested including: included vaccine technologies that use messengerRNA (mRNA); viral vectors, such as adenovirus; and protein subunits to provoke immune response.

Five of the six vaccine candidates that have been supported by the US government are currently in Phase 3 trials, two since late July, with the number of Phase 3 trial participants ranging from 30,000 to 60,000, depending on the design of the trial.

Fauci hailed the “major financial risk” taken by government investments that not only funded vaccine resaerch, but also manufacturing and pre-purchase agreements,  in order to “save time without compromising safety or compromising scientific integrity.”

United States Infection Rates Far Outpaced Europe’s – Although Right Now They Are Converging

In terms of infection trends, Fauci’s review highlighted the stark differences that have been seen between the United States and Europe in terms of their response to the virus and the overall pattern of infections.

The United States did not shut down both outdoor and indoor spaces such as workplaces, parks, and grocery stores.  And so, the baseline of US infections never really dipped to the low levels seen by the European Union over the summer, he said.  Although as rates now resurge in Europe, they are in fact converging with those seen right now in the US.

In the US, rapid reopening the country and the economy in the late spring, especially in the south states of Florida, Georgia, Texas, Arizona, and southern California  led to a summer-time peak in new cases of up to about 70,000 a day; this has now plateaued to around 40000 to 50000 cases a day – but may still rise yet again this winter.

“As we’re getting into the cooler weather, we’re getting more and more cases so this looks like we’re going to have a difficult fall and winter,” Fauci said, adding that a potentially  new surge in the US would now begin from a much higher overall rate.

US Sees Huge Asymptomatic Transmission and Big Racial and Ethnic Disparaties

A continuing feature of the virus – and challenge to its containment – are the very high-rates of asymptomatic transmission of the virus, he added.

“You don’t need to be coughing or sneezing, to transmit the infection. An important component that distinguishes this infection from so many other viral infections is that about 40-55% of people are asymptomatic.” 80% of people infected have mild to moderate manifestations that don’t require immediate hospitalization, while the other 15-20% have severe or critical manifestations of the virus that have a wide variability, where up to 25% of severe cases require mechanical ventilation.

Along with that, he said: “One of the characteristics of this disease that is most disturbing is the extraordinary racial and ethnic disparities.”

Minorities groups such as African Americans, Latinos, Native Americans, Alaskan Natives and Pacific Islanders have a higher incidence of getting infected, in the US, he noted.

This is primarily because of the nature of their jobs as frontline workers in the community, which means they are exposed to many more people in the course of their day.  It is also because of the higher incidence and prevalence of many underlying health conditions conditions among the same groups, which often live in more socio-economically deprived communities.  And these conditions,  in turn, lead to more severe outcomes from COVID-19.

“Including old age, which increases the risk of severe COVID-19 illness, obesity is emerging as an important co-morbidity, as well as diabetes, chronic obstructive pulmonary disease, and a variety of heart conditions,” said Fauci.

After Approval, Vaccines Still Need to Demonstrate “Worthwhite Efficacy” – Vaccine Hesitancy Needs to be Addressed

Even if a vaccine is demonstrated to be safe and effective, many more questions will still need to be answered about how effective the vaccine may really be.

There are several ways that vaccines can demonstrate “worthwhile efficacy,” said Vasee Moorthy, an R&D specialist at WHO.

“Aalways bear in mind that we only know the real vaccine efficacy much later, when the vaccine has been given to many more people. We don’t want to inappropriately declare a winner based on one of the early results,” she said.

Phase 3 trials, and their follow-up, need to be looking at enough “endpoints” or indicators of disease and severe disease, between the groups randomized to receive the vaccine and those that received placebo.  With limited information on safety, she applauded the deicison of pharma companies to “pause and reassess the situation whenever there are adverse outcomes during clinical trials.”  Adverse effects have so far caused pauses in two trials, run by AstraZeneca and Johnson&Johnson.

The importance of combating vaccine hesitancy was also underlined, by Jeff Lazarus, Associate Professor at the University of Barcelona.

To combat hesistancy, trust in government needed to be strong, government health communication needed to be consistent and  flexible, and leaders need to avoid the politicization of COVID-19 related issues – a pitfall into which many countries have fallen.

“Communication should be two way with informing the public and promoting mutual understanding and acceptance. Trust in government and health officials can improve public cooperation with pandemic measures,” Lazarus said.

Image Credits: R Santos/HP Watch.