An infectious diseases expert who has been religiously following COVID-19 numbers shares that the country’s doubling time has increased, a positive trend. Although more accurate data and more testing are needed. BY BENJAMIN CO, MD

Infectious diseases and clinical pharmacology expert Dr. Benjamin Co is back again with a COVID-19 update, a particularly positive one that you might find interesting. The industrious physician, who has been breaking down coronavirus numbers in his personal blog since the outbreak started, says that the “doubling time”—a number tells us how many days it takes for confirmed cases to double based on the 7-day average daily growth rate—has increased. The bigger the doubling time, Co says, the earlier we flatten the curve.

Here is his blog post in full. We have chosen to highlight the Philippine data first in terms of order:

Philippine Statistics

Refer to the link DOH.gov.ph or up-to-date data or to COVID19.gov.ph. (The latter is not a secure site.) The new site for the Department of Health is user friendly, provides more information but is still direly lacking in what the relevant information should be. I advise the readers to look through their official site.

COVID19stats.ph is a new site which gives you a very good summary of the Philippines data. (summary of those that are unable to access this site is seen below)

On April 1, the official report of cases was 2,311. The total number of cases to date is 6,259. This approximates an average of around 220 cases per day. But the fluidity of events including how effective the ECQ (enhanced community quarantine), additional testing capabilities are factors that will affect the numbers in the subsequent weeks.

The figure below shows the daily new cases (blue), new deaths (red) and new recoveries (green) since the start of the first case reported in the country. Notice the increase in new cases after the initial Metro Manila quarantine followed a day later by the Luzon-wide ECQ (enhanced community quarantine). When mass testing had begun in some sectors, the number of new cases started to decline. The green line shows the slow and gradual increase in daily recoveries.

Note that the recoveries in green have been higher than the deaths in red for the past three days.

An important data is the doubling time. The doubling time tells us how many days it takes for confirmed cases to double, based on the 7-day average daily growth rate. In short, the shorter the doubling time, the steeper the slope, the larger the number of cases within that span of time. The doubling time in the US for example is around 4 days. Which means that if the doubling time does not lengthen in the US, they would see an increase of 100,000 cases every three days. The doubling time in the Philippines started around four, but now averages at least two weeks (14 days). The latest doubling time is now almost 16 days! Remember, the longer the doubling time, the earlier we can flatten the curve.

A case is considered closed when patients either recover or die.

The table above shows the number of closed cases in the South East Asian region. The Philippines has 981 closed cases. This means that of the 6,259 cases to date, 981 have had outcomes—with 58 percent recoveries (572 cases) and 42 percent (409) resulting in death.

On the Department of Health website, there are 2,159 patients that are still for “validation.” These 2,159 patients are confirmed positive cases, but their outcomes are undetermined. If they are positive, asymptomatic, and home quarantined, what is the current status of these cases that are for “validation” and how are the various local government city health offices assisting the Department of Health in having these patients retested?

Are we testing enough?

The figure below shows the overall summary of SARS-CoV-2 testing in the country as of April 17, 2020. On the average, more than 86 percent of patients tested (with symptoms or asymptomatic or those who came in contact with positive patients) would test negative.

SARS-CoV-2 Testing in the Philippines

The figure below shows the tests conducted, number of people tested, and those who turn out positive or negative. The trend is simple to follow. At least 14 percent of patients tested turned out positive while 86 percent turned out negative. This was consistently seen in the past week. The less we test, the less the positives reported. For example, on April 11, 1,212 tests were conducted on 1,014 individuals (please note that some patients will require repeat tests for some reason or another). There were 96 positives while the remaining 920 were negative.

On April 13, 2,611 tests conducted on 2,299 individuals were done resulting in 409 positive and 1,877 negative. By April 16, almost 4,000 patients were being tested daily On April 17, 3,966 tests were conducted among 3,733 individuals tested. Of these 396 tested positive (10.6 percent) and 3,337 tested negative (89.4 percent). Yesterday, April 18, 3,880 tests were conducted with 3,224 individuals tested. Of these, 272 tested positive while the remaining 2,949 tested negative.

The more we test, the higher the chances of not missing out on positive patients and seeing the bigger picture of the pandemic in the country. Having more positive cases is important as it triggers the agency to be more efficient in doing contact tracing, segregating and monitoring properly all positives and their contacts, and properly recording all outcomes whether they are home quarantined or hospitalized. Accurate epidemiological data is important for decision making.

What remains unsettling is a few discrepancies in data. For example on April 8, there were 2,740 tests conducted on 3019 subjects. 2,826 of them subjects were negative while only 204 were positive. While it is understandable that some patients may need retesting, it is confusing why there will be more subjects than tests conducted.

SARS-CoV-2 testing. Note that the more the tests conducted, the higher cases reported.

The trend of recoveries is expected to rise this week as we see the patients who were positive, admitted and discharged come home this week.

It is vital that reports come in on time. Based on the data from the DoH, note the reporting latency below for recoveries and for deaths:

Only a little more than 30 percent of recoveries are recorded within three days. The majority are reported after eight days or longer with an average of almost one week before a recovery is announced publicly. With respect to reporting of deaths, almost half are announced within the first three days of demise while about 25 percent are reported after eight days. It take almost five days after the demise of a patient before a death is announced publicly. This provides inaccurate picture of the ongoing outbreak in the country and may impact on exit strategies for the government. The delayed reporting (backlogs from testing centers) and missing follow-up recoveries may account for our lower than the regional and global average of recovery and fatality rates.

Most of the cases are males (54 percent) while the remaining are females (46 percent).

Additional demographics include:

Top Ten Cities with COVID19 cases in the Philippines

While Quezon City has more than 1047 cases, they are also the most dense population. It is important to consider recovery and death rates based on the number of cases in the city. For example, if you had 10 reported cases and 10 deaths, that would mean 100 percent case fatality rate.

Among the cities in Metro Manila, Pasig (14.5 percent) has the highest case fatality rate, followed by Caloocan (8.5 percent) and Marikina (8.5 percent), Quezon City (7.5 percent), Manila (7.4 percent), and Muntinlupa (7.4 percent). (Note that all these data are from the Department of Health. Local Government Units data are provided by respective LGUs and are not in congruence with the DoH data.)

Regions with more than 50 COVID19 cases in the Philippines

The table above shows the regions with more than 50 COVID 19 cases in the country. While NCR has the most cases, the highest case fatality rate is in the Ilocos Region (19.23 percent), followed by Davao Region (15.7 percent), Western Visayas (13.32 percent), Central Luzon (7.73 percent), Central Visayas (7.6 percent) and Calabarzon (6.86 percent). The fatality rate of the National Capital Region is only 6.29 percent, the lowest among the top seven regions with cases more than 50 cases of COIVD19. This is because the NCR is also the most densely populated. This accounts for more cases being reported and while there are more deaths, these are proportional to the number of cases.

A large clump of patients are those more than 45 years old.

More recoveries in the younger age group (<54 years old)

Higher case fatality rates in patients >55 years old and is highest among the senior citizen group (~44 percent).

The Department of Health hotline is (02)8-6517800 loc 1149-1150. People who present with fever and/or respiratory symptoms are encouraged to get in touch with the DoH.

Global statistics

[The updates for the topic “Pandemonium” on this blog site provides a rundown on the daily statistics of this viral infection. As the number of cases globally have spread, it’s difficult to keep up with each and every case. The “brief” will be kept short and simple and center on the cases in the Philippines based on information from the Department of Health. Readers are asked to refer to other sites, especially Worldometers.info, or WHO.int for specific information in particular countries.]

Update as of 7pm 19 April 2020 (Sunday)

Total cases: 2,341,958 (yesterday: 2,262,799)

The total number of cases worldwide is approaching the 2,400,000 mark with 80,000 cases overnight compared to the previous day of a little over 70,000 cases. Note that the average case fatality rate for COVID-19 is now at 6.89 percent.

Total deaths: 160,956

Total recovered: 601,362

Cumulative case fatality rate: 6.89 percent (yesterday: 6.85 percent)

Recovery rate: 25.68 percent (yesterday: 25.68 percent). This recovery rate is stable around 25 percent due to the unusual number of cases overnight and higher number of deaths. Just the last 22 days alone, we saw almost 2.2M new cases, accounting for almost 94 percent of the total cases to date.

Active Cases vs. Closed Cases

Of the total 2,341,958 cases (as of this writing), almost 1.6M are active (currently infected cases). The remaining 762,318 already had an outcome—either recovered or died.

Total cases worldwide

The total cases is now approaching the 2,400,000 mark. On March 6, the 100,000 cases was reached (102,050). It took a little less than 1 month to reach the 1,000,000th case. This was breached on April 2, 2020 (1,016,948 cases). The average trend today approximates 75,000 cases per day. If this rate is not decreased, the world will close in on 3,000,000 cases on or before the end of April 30. Majority of the world cases are from the United States, Europe and the United Kingdom. This is roughly an average of 1,000,000 cases approximately every 4 weeks.

The next two graphs will show the cumulative number of cases (by number of days since 10,000 cases were reached) and the cumulative number of cases (by number of days since 100 deaths were reached) from the top 7 countries that contribute to the pool of cases in the world. The United States of America contributes to almost 1/3 of the total cases in the world.

The United States has the steepest climb averaging 30,000 cases daily the past week as they approach the 750,000 total cases. China and Iran have plateaued. The other countries in the top seven are still seeing increase in cases but at a much lower rate compared to the past month.

The number of deaths due to COVID-19 in the United States now far exceeds that of Italy, as they approach the 40,000 mark. Deaths continue to increase significantly for France, Italy, and Spain. Germany, Iran and China on the other hand are seeing a plateau in the death rates.

The United States of America has almost nine times (893 percent) the number of cases of China. It leads globally in the number of total cases at 735,287 and a case fatality rate (CFR) up at 5.32 percent (from 5.25 percent yesterday) with almost 40,000 total deaths recorded. The recovery rate for the US is up at 9.1 percent in spite of the large number of new cases overnight. New York has 241,041 cases with 17,671 deaths or a CFR of 7.33 percent.

China reported 16 new cases and no new deaths. The case fatality rate of China stands at 5.6 percent. The recovery rate of China is at 93.14 percent. They are 7th in ranking, with the United Kingdom displacing them for the sixth spot. The UK now has 115,314 cases and 15,498 deaths (CFR=13.44 percent). The marked increase in death rates in the UK to exceed the CFR of Italy that has 23,227 deaths from 175,925 cases (CFR = 13.2 percent).

The recovery rate of the UK is the lowest of 142 countries with more than 50 reported cases at 0.36 percent.

Top Twenty Countries in the World with COVID-19 Cases

Total cases, recoveries, and deaths of top 20 countries with COVID-19.

The median average of case fatality rates is now at 6.89 percent and is predicted to climb to >7 percent