The rise in new cases of COVID-19 seemed to be slowing in mainland China, but concerns remain about local transmission in cities abroad such as Hong Kong, Singapore, and Japan, and on cruise ships.

China has confirmed 70644 cases and 1772 deaths as of 5 p.m. Central European Time, representing an increase of 2060 cases in the last 24 hours, according to the latest Chinese data. This comes even after the Chinese health authorities expanded diagnostic criteria to count “clinically confirmed” cases on top of lab-confirmed cases, the rate of new infections appears to have slowed.

However, “this trend must be interpreted very cautiously,” WHO Director General Dr Tedros Adhanom Ghebreyesus told reporters at a press briefing Monday. “It is too early to tell if this reported decline will continue.”

The slow, but steady growth in cases outside of China, however, particularly in Singapore and Japan, has also been a cause for concern among public health experts closely watching the epidemic unfold.  A total of 694 cases in 25 countries have been reported, along with three deaths.

Of particular note is yet another huge spike in the number of infections on the quarantined cruise ship, the Diamond Princess, to 454 confirmed cases as of Monday evening, which now represents the largest cluster of cases outside China. Some 189 passengers were classified as “asymptomatic carriers,” according to a statement from Japan’s Ministry of Health. The ship has been docked in Japan’s Yokohama port since 3 February.  Many of the original 3,600 passengers remain under a two-week quarantine while the Japanese government tests every one on the ship.  Some 1,723 have been tested so far. Those found to be infected with the virus, elderly people and those with other medical conditions have been allowed to disembark and complete their quarantine period in special facilities on shore.  Most of the 400 Americans on board the ship were evacuated earlier this morning, although they will they will have to undergo another two weeks of quarantine in the United States.

The strict measures being enacted for passengers on the Diamond Princess were not repeated for the Westerdam, a cruise ship that was finally allowed to dock in Cambodia last week after being stranded at sea for two weeks. Once clearing temperature and health checks, passengers were allowed to continue on their travel itineraries. However, one COVID-19 case was confirmed in a passenger after she had already disembarked and traveled to Malaysia.

Two more former Westerdam passengers, were, however, suspected of being ill are awaiting lab results for the virus after traveling to Singapore. Some 255 guests and 747 crew members are still waiting aboard the ship to complete further health checks.

Holland America, the owner of the Westerdam, said in a statement that no passengers had elevated temperatures upon disembarking. The 20 individuals who reported to the ship’s medical center also later tested negative for COVID-19.

The drastically different treatment of the passengers on the Westerdam and Diamond Princess highlight the very different national policies governing public health responses to contain the spread of the virus, as well as the different circumstances involving each ship. WHO’s Director General Dr Tedros Adhanom Ghebreyesus last week strenuously urged the government of Cambodia to allow the cruise ship to dock.  In the aftermath, he has not commented on the discovery of cases aboard the second ship, or on the very different procedures undertaken by Cambodia to screen and disembark passengers, as compared to Japan.  The Westerdam, which departed Hong Kong on 1 February had not identified any cases aboard while at sea, although the incubation period of the virus is believed to average 14 days.

“Measures should be taken proportional to the situation… Blanket measures may not help,” said Dr Tedros, in a press briefing today. “”There is no zero risk…[every action] has to be proportional to the situation.”

Will COVID-19 Become a Pandemic?

Experts are worried that, despite the decline in new cases on mainland China, there may be potential for further spread, leading to some questioning whether it was time to label the outbreak a “pandemic” – or a global outbreak where every citizen could be infected.

The media frenzy around the outbreak has also been whipped up by published and pre-print studies estimating that the current number of infections is much higher than reported due to a high number of asymptomatic and mild cases, with some estimates in the range of 75,000 thousand infections in Wuhan alone. A WHO advisor, Ira Longini from the University of Florida, was quoted by Bloomberg News as projecting that up to two-thirds of the world’s population could be afflicted by COVID-19 if current measures to contain the virus’ spread are unsuccessful.

However, WHO scientists are cautious about using the “p” word, for fear of inducing widespread panic.

“For the general public, I think [pandemic] means the worst-case scenario. We need to be cautious… because it can create panic unnecessarily,” said WHO’s Sylvie Briand in Monday’s press briefing.

Added Mike Ryan, WHO’s head of Emergencies, “We have said that the risk for regional and global spread is high – that is not high of a pandemic, it’s high for further spread.

“We need to be careful not to drive fear in the world right now.”

On the WHO advisor’s prediction that the majority of the world could get infected by COVID-19, Ryan added that, “all predictions are important. But most predictions are wrong.”

Image Credits: Flickr/ Yoshikazu TAKADA, ncov.dxy.cn.