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During this time of community quarantine, it is vitally important that we keep the senior citizens at home as most of them may be immunocompromised. But have you ever wondered why the age group 0-19 need to be quarantined as well? Well, a recent study using an agent-based SIR MOCOS model, indicates that social distancing and quarantine of these age groups drastically affect the progression of the spread of COVID-19.

In the semi-realistic simulations based on the MOCOS model, it is assumed that Iligan City is at first virus-free with ten (10) imported cases. It is assumed that no other infectious persons appear in the city throughout the time of the simulation. This is such a conservative estimate due to the number of people commuting to Iligan City everyday.

Modelling has aided the local government of Iligan City in implementing pandemic response strategies as suggested from the following simulated but practical scenarios.

Scenario 1: Opening Iligan City with Social Distancing

The restriction on the reduction of outer household contacts is compared at 0%, 50% and 75%. A 50% and 75% decrease in social contacts would mean that if one has on the average 20 contacts per day, these contacts should be decreased to 10 and 5, correspondingly.

Clearly, with mitigation the ICU threshold is reached in around 20 days after lifting of ECQ, but social distancing delays the saturation of the healthcare system by at least 10 days. The greater the reduction in social distancing, the longer it takes to reach the full effect of the disease on the population.

Scenario 2. Gradual opening of Iligan City with social distancing only

The use of the MOCOS model also has shown that the opening of MSU-Iligan Institute of Technology, the largest academic institution in Iligan City, can result in a massive spreading from the students to the city and the households. So, in the scenarios for the gradual lifting of ECQ in the city, schools are closed, work has resumed but only essential businesses and transport are operational. This excludes opening of malls, restaurants, entertainment, gaming and fitness centers and other public places like churches, pools, etc. No outside cases of infectious persons are also imported into the city for the duration of the simulations which would otherwise increase the rate at which the epidemic spreads.

Observe from Figure 2, that by decreasing social contacts in the workplaces and essential business by 75%, the saturation of the ICU capacity is delayed from 32 days to 77 days, with projected deaths of about 2500, a decrease from 3000, when no mitigation is implemented. It can be seen that social distancing with continued closure of schools and non-essential businesses, significantly delays the progression of the spread. The ICU threshold and the number of deceased individuals are lower compared when no mitigation is implemented. Thus, social distancing with gradual lifting of ECQ is suggested. Furthermore, Figure 2 shows that at the peak of the progression of the infection, the age groups with the highest fatality are those 60 and above.

Scenario 3: Gradual opening of Iligan City with social distancing and age-specific quarantine measures

To look into the age groups, similar simulations are done where the schools are still closed, work has resumed with only essential businesses are open, but the age group having median age 65 and above are quarantined in their homes to safeguard from unnecessary outside exposure.

From Figure 3 (b), social distancing with 75% reduction in social contacts, decreases the projected number of infections by a third, from about 30,000 to 10,000. From Figure 3 (c), when senior citizens are home quarantined, the cases further decreased to about 4500, which is more than half. From the work of Prem et al. (2017), the age group 0-19 are the ones with the highest expected contacts on the same age group and on other age groups. So when this age group is also home quarantined, the peak of infections is decreased significantly to ~1500 cases, as shown in Figure 3 (d). The effect on the number of hospitalized individuals is likewise noticeable.

Social distancing and quarantine of these age specific groups, greatly help in slowing down the spread of the infection and saturation of the healthcare system.

For the youth and the senior citizens, quarantine is not imposed to suppress you but to protect you instead. Next time you are tempted to disregard distancing from friends and contacts outside your homes, think twice! Each of us is vitally important in this fight against COVID-19!

Read more on this report here: MOCOS Case Study for the Gradual Lifting of ECQ in Iligan City, Philippines by Wolfgang Bock, Jinky B. Bornales, Johniel Babiera, Randy Caga-anan, Dubhe Joy Carmen, Rey Cuenca, Dante Dinawanao, Gabriel Engcong, John Alfred Liwanag, Jennifer Joyce Montemayor, Daisy Lou Polestico, Ruth Serquiña