WHO: Look beyond virus case numbers, study clusters

MANILA, Philippines _ The World Health Organization (WHO) on Tuesday urged governments to conduct “exhaustive investigations” into disease clusters and not just rely on numbers and projections to better understand how the new coronavirus is spreading in communities and so that they could properly respond.

Mike Ryan, executive director of the WHO’s Health Emergencies Program, told reporters in an online briefing that although it was important to hypothesize and make models on the disease’s spread, a “careful, systematic and exhaustive investigation” of disease clusters was what would give governments the answers to what was really happening and what was causing the amplification of the disease in a specific locality.

Ryan pointed out that while nobody wanted to see a clustering of coronavirus cases in the communities, such a situation provided health authorities the opportunity to better understand the “circumstances, context, behaviors in which the disease transmits more readily.”

What’s driving infection

“We need to have our scientists around the world investigating clusters, seeing what’s driving infection … If we get that, we will build up a much better picture of the public health advice we need to give our communities. On what behaviors to avoid, what places to avoid, what circumstances to avoid,” he said.

“I do think this is an important issue, inasmuch as it demonstrates that rapid response to contain clusters and systematic thorough investigations of those clusters is both a public health act to stop the disease and an act of public health discovery to understand how this disease transmits in these circumstances,” he added.

According to Maria Van Kerkhove, technical lead of the Health Emergencies Program, it is essential for every country to understand the nature of the case clusters it is seeing and what brought it about “because that will help us understand and bring it under control.”

The last time the Department of Health (DOH) publicly discussed clusters of infection in the country was in late April when 18 clusters were identified.

One of the biggest clusters was traced to Greenhills Shopping Center in San Juan City, which accounted for 45 positive cases, six of whom were their close contacts.

Another cluster of infection was traced to the cockfight derbies held at Matina Gallera in Davao City on March 7, 10 and 12. Fourteen people were confirmed positive for the coronavirus.

Late on Monday, President Duterte placed Cebu City back on strict lockdown after 61 of its 80 barangays reported active coronavirus cases.

Both Malacañang and the DOH, however, have yet to provide information on what is driving the infection in the city, which is the gateway to the Visayas.

Population density

In his press briefing, presidential spokesperson Harry Roque surmised that population density was “part of the problem” as he pointed out that there are communities where it is difficult to practice physical distancing.

Last week, Health Undersecretary Maria Rosario Vergeire said the increase in cases in Cebu might be due to its aggressive contact tracing efforts and testing. She noted then that the epidemiology bureau was already plotting the onset of illness of cases there to see the trend.

In just two weeks, new cases in Metro Manila grew by 1,152 to 3,145 from 1,993 a month ago. Cebu City, on the other hand, saw its new cases grow by 576 to 794 from 218 during the same period.

While Metro Manila saw a much larger growth in new cases than Cebu City, it wasn’t placed back on strict lockdown on Monday because its health system was still capable of coping unlike that of Cebu.

On Tuesday, the DOH reported 364 more cases, pushing the nationwide tally to 26,871.

Of the new cases, 249 tested positive in the last three days. Metro Manila accounted for the most of those cases, 128, followed by Central Visayas, 56.

There were 115 late cases, or those who tested positive from at least four days ago. Metro Manila still had the biggest number of these cases, 24.

The DOH recorded its highest single-day increase in the number of recovered patients on Tuesday as 301 were cleared of the virus, bringing the total number of survivors to 6,552.

But the death toll rose to 1,103, with the deaths of five more patients.