Monkeys infected with COVID-19 develop immunity in studies, a positive sign for vaccines

By Julie Steenhuysen

CHICAGO (Reuters) – Two studies in monkeys published on Wednesday offer some of the first scientific evidence that surviving COVID-19 may result in immunity from reinfection, a positive sign that vaccines under development may succeed, U.S. researchers said on Wednesday.

Although scientists have assumed that antibodies produced in response to the new coronavirus virus are protective, there has been scant scientifically rigorous evidence to back that up.

In one of the new studies, researchers infected nine monkeys with COVID-19, the illness caused by the novel coronavirus. After they recovered, the team exposed them to the virus again and the animals did not get sick.

The findings suggest that they “do develop natural immunity that protects against re-exposure,” said Dr. Dan Barouch, a researcher at the Center for Virology and Vaccine Research at Harvard’s Beth Israel Deaconness Medical Center in Boston, whose studies were published in the journal Science.

“It’s very good news,” Barouch said.

Several research teams have released papers – many of them not reviewed by other scientists – suggesting that a vaccine against the virus would be effective in animals.

In the second study, Barouch and colleagues tested 25 monkeys with six prototype vaccines to see if antibodies produced in response were protective.

They then exposed these monkeys and 10 control animals to SARS-CoV-2, the official name of the novel coronavirus.

All of the control animals showed high degrees of virus in their noses and lungs, but in the vaccinated animals, “we saw a substantial degree of protection,” Barouch said. Eight of the vaccinated animals were completely protected.

These studies, which have been peer reviewed, do not prove that humans develop immunity or how long it might last, but they are reassuring.

“These data will be seen as a welcome scientific advance,” Barouch said.

(Reporting by Julie Steenhuysen; Editing by Bill Berkrot)

New coronavirus adapts to populations; vaccine works in monkeys

By Nancy Lapid

NEW YORK (Reuters) – The following is a brief roundup of the latest scientific studies on the novel coronavirus and efforts to find treatments and vaccines for COVID-19, the illness caused by the virus.

New coronavirus is adapting to different populations

A genetic analysis of samples from more than 7,500 people infected with COVID-19 suggests that as the new coronavirus spreads quickly around the world, it is adapting to its human hosts, researchers reported on Tuesday in the medical journal Infection, Genetics and Evolution. They found almost 200 recurrent genetic mutations of the new coronavirus – SARS-CoV-2 – that show how it may be evolving as it spreads in people.

“All viruses naturally mutate,” Francois Balloux of University College London, who co-led the research, told Reuters. “Mutations in themselves are not a bad thing and there is nothing to suggest SARS-CoV-2 is mutating faster or slower than expected. So far, we cannot say whether SARS-CoV-2 is becoming more or less lethal and contagious.”

Experimental vaccine protects macaques from SARS-CoV-2 infection

In macaque monkeys, an experimental vaccine for the novel coronavirus safely induced antibodies that blocked several different SARS-CoV-2 strains, Chinese researchers reported on Wednesday in the journal Science. The researchers say tests of their vaccine candidate, “PiCoVacc,” in humans will likely begin later this year.

The true prevalence of problems with smell and taste among patients infected with the novel coronavirus may be higher than doctors realize, according to researchers who reviewed 10 studies published earlier this year. Among a total of more than 1,600 infected patients in North America, Asia and Europe, nearly 53% had diminished or loss of sense of smell, and nearly 44% had problems with taste. In the subset of studies that used particularly reliable tests to evaluate patients’ ability to smell and taste, rates of dysfunction were even higher, suggesting “that the true prevalence of dysfunction in COVID-19 patients may remain underestimated,” the research team wrote on Tuesday in the journal Otolaryngology-Head and Neck Surgery. Increased awareness “may encourage earlier diagnosis and treatment of COVID-19, as well as heighten vigilance for viral spread.”

Researchers list ways to ease the stress of frontline caregivers

There are many well-documented methods hospitals could use to help ease frontline caregivers’ emotional stress, according to researchers who reviewed dozens of studies of healthcare staff working during outbreaks of emerging viruses. Broadly, they say, interventions fall into the categories of clear communication, access to adequate personal protection, adequate rest, and practical and psychological support.

Among their specific recommendations are changes to practice, such as screening stations to funnel infected patients to specific areas, redesigning procedures that pose high risks for the spread of infection, and reducing the density of patients on wards. They wrote on Tuesday in The BMJ that interventions shown to be helpful in the earlier studies “were similar despite the wide range of settings and types of outbreaks … and thus could be applicable to the current COVID-19 outbreak.” (https://bit.ly/2SHJxmj)

(Reporting by Kate Kelland and Nancy Lapid; Editing by Bill Berkrot)