Experts say aggressive lockdown measures have slowed the 'first wave' of the coronavirus but a 'balance' must be kept until a vaccine arrives

AP Photo/Ted S. Warren

Pharmacist Michael Witte, left, gives Rebecca Sirull, right, a shot in the first-stage safety study clinical trial of a potential vaccine for COVID-19, the disease caused by the new coronavirus, Monday, March 16, 2020, at the Kaiser Permanente Washington Health Research Institute in Seattle. Sirull is the third patient to receive the shot in the study

• While lockdown measures have been effective in curbing the spread of the new coronavirus, experts warn that loosening restrictions too much before a vaccine is available may lead to a resurgence of cases.
• According to a new study led by researchers at Hong Kong University, there is still a "substantial risk" of new infections, particularly from travelers, and the virus needs to be closely monitored in order to prevent another outbreak.
• "Although control policies such as physical distancing and behavioral change are likely to be maintained for some time, proactively striking a balance between resuming economic activities and keeping the reproductive number below one is likely to be the best strategy until effective vaccines become widely available," said the study's lead researcher Joseph Wu.
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Lockdown measures have been effective in curbing the "first wave" of the new coronavirus spread, a new study led by researchers at Hong Kong University has found. But experts warn that loosening restrictions too much before a vaccine is available may lead to a resurgence of cases.

The study, published in the Lancet medical journal on Wednesday, was first reported on by The Guardian. The research is based on modeling of the virus spread in China, which appears to have been contained as the country has not reported any new domestic cases since March 19.

"The first wave of COVID-19 outside of Hubei has abated because of aggressive non-pharmaceutical interventions," the study found.

According to the research, China has been able to greatly reduce the virus' reproduction number - meaning, the number of people on average that one person can infect - from two or three to just under one.

But the study warned there is still a "substantial risk" of new infections, particularly from travelers. It stressed that the virus spread needs to be closely monitored in order to prevent another outbreak, or "second wave" of the disease and achieve "an optimal balance between health and economic protection."

"Although control policies such as physical distancing and behavioral change are likely to be maintained for some time, proactively striking a balance between resuming economic activities and keeping the reproductive number below one is likely to be the best strategy until effective vaccines become widely available," said Joseph Wu, who leads the infectious disease modeling research at the Hong Kong University's School of Public Health and co-led the study.

The virus has infected over 1.5 million people worldwide and killed over 88,000. China, once the epicenter of the disease, has reported just over 82,000 cases and 3,337 deaths.

According to Business Insider's Rebecca Cairns, there are over 40 research teams developing a vaccine for COVID-19. But according to The Oxford Vaccine Group, producing an effective and safe vaccine can take between five to ten years, though research can often be expedited during times of outbreak due to increased funding.

"Given the current severity of the crisis, there are efforts to fast-track a vaccine for COVID-19 in as little as 12 to 18 months," said Abe Malkin, MD, founder and medical director of Concierge MD in Los Angeles.

Still, other experts have warned that producing a viable vaccine is a long and intensive process, and clinical trials can take months.

"It seems promising, but there is no guarantee that any of the vaccines will evoke a strong enough immune response," said Brendan Wren, a professor of microbial pathogenesis at the London School of Hygiene & Tropical Medicine.

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