Pandemic now driven by 20s, 30s, 40s group, many asymptomatic: WHO
The World Health Organization said on Aug. 18 it was concerned that the novel coronavirus spread was being driven by people in their 20s, 30s and 40s, many of which were unaware they were infected, posing a danger to vulnerable groups.
WHO officials said this month the proportion of younger people among those infected had risen globally, putting at risk vulnerable sectors of the population worldwide, including the elderly and sick people in densely populated areas with weak health services.
"The epidemic is changing," WHO Western Pacific regional director, Takeshi Kasai, told a virtual briefing. "People in their 20s, 30s and 40s are increasingly driving the spread. Many are unaware they are infected."
"This increases the risk of spillovers to the more vulnerable," he added.
A surge in new cases has prompted some countries to re-impose curbs as companies race to find a vaccine for a virus that has battered economies, killed more than 770,000 people and infected nearly 22 million, according to a Reuters tally.
Surges were reported in countries that had appeared to have the virus under control, including Vietnam, which until recently went three months without domestic transmission due to its aggressive mitigation efforts.
"What we are observing is not simply a resurgence. We believe it's a signal that we have entered a new phase of pandemic in the Asia-Pacific," Kasai said.
He said countries were better able to reduce disruption to lives and economies by combining early detection and response to manage infections.
While mutations had been observed, the WHO still saw the virus as "relatively stable", Kasai said.
WHO also reminded drugmakers to follow all necessary research and development steps when creating a vaccine.
Socorro Escalante, its technical officer and medicines policy advisor, said the WHO was coordinating with Russia, which this month became the first country to grant regulatory approval for a COVID-19 vaccine.
"We hope to get the response in terms of the evidence of this new vaccine," Escalante said.
Britain urged elderly people and volunteers from Black and Asian minority groups to sign up to a COVID-19 vaccine trial registry to boost efforts to find a working vaccine against the disease that offers protection for higher risk groups.
Australia was on track to record its lowest one-day rise in new COVID-19 infections in a month, lifting hopes that a stringent lockdown in the country's second-most populous state has prevented a fresh wave of cases nationally.
New Zealand reported 13 new cases for the last 24 hours, as the country battles to contain an outbreak in the biggest city of Auckland.
Brazil reported more than 19,000 new infections and 684 deaths in the past 24 hours, and its third-largest pork and poultry processor Central Cooperativa Aurora Alimentos has agreed to test 11,000 workers.
Mexico reported 3,571 new cases of the coronavirus and 266 additional deaths, pushing the total death toll to beyond 57,000.
Venezuela's rate of COVID-19 infection is set to overwhelm its testing capacity, likely leading to an artificial flattening of the contagion curve, a lawmaker and medical adviser to Venezuelan opposition leader Juan Guaido said.
Removing quarantines to boost travel
Airlines and airports will ask a UN-led task force meeting on Aug. 18 to recommend countries accept a negative COVID-19 test within 48 hours of travel as an alternative to quarantines that have decimated demand for travel, according to a document seen by Reuters.
The proposal calls for the use of PCR (Polymerase chain reaction) tests conducted outside of airports. While task force recommendations are voluntary, International Civil Aviation Organization (ICAO) guidelines are typically adopted by its 193-member countries.
The increasingly common D614G mutation of the novel coronavirus found in Europe, North America and parts of Asia may be more infectious but appears less deadly, according to Paul Tambyah, senior consultant at the National University of Singapore and president-elect of the International Society of Infectious Diseases.
Evidence suggests the proliferation of this mutation in some parts of the world has coincided with a drop in death rates, suggesting it is less lethal, said Tambyah, adding that most viruses tend to become less virulent as they mutate.
"It is in the virus' interest to infect more people but not to kill them because a virus depends on the host for food and for shelter," he said. Scientists discovered the mutation as early as February, the World Health Organization said.
Mild COVID-19 induces prolonged immune response
A study from China last month on 349 COVID-19 patients, which has not yet undergone peer review, found similar immune response patterns at six months, regardless of symptom severity.
In another study published on Aug. 16 ahead of peer review, U.S. researchers performed blood tests in 15 patients after mild COVID-19, and found all three signs of lasting immune responses they were looking for: antibodies, so-called memory B cells, and memory T cells.
Test results at three months were unchanged from results at one month, so study co-author Lauren Rodda of the University of Washington School of Medicine and her team believe this is a lasting response. Both studies were posted on the website medRxiv.