proposal

Security against Infectious Disease Threats
--- Policy Responses Abroad

Takashi Sekiyama
Associate Professor, Kyoto University

1. Introduction

If it is the government's security responsibility to protect the people's life and property and economic and social stability, governments are required to undertake preparedness and countermeasures associated with the prevention and early detection of, as well as prompt response to, infectious diseases. Security is an equivocal notion, but it can be generalized as an act to protect "something" (object) from "something" (threat). Infectious diseases, whether of natural or artificial (biological weapons, bioterrorism) origin, are threatening not only the safety of life of individuals but also the nations and the international community directly or indirectly. The spread of infectious diseases worldwide has various impacts on society --- population decline, labor shortage, the disruption of economic activities (production and consumption), the decrease of supply, the increase of demand, the shortage of specific resources due to buying up, and large-scale movements of the population to escape the threat of infectious diseases.

The novel coronavirus is gravely affecting human life, economy, and society around the world, but the degrees of damage vary widely from country to country. In the United States, Brazil, India, and Russia, COVID-19 continues to spread, while South Korea, Taiwan, Thailand, and Vietnam control it relatively well. European countries, such as the United Kingdom, France, Germany, and Italy, initially could not check the spread of the disease but are now calming down the infection. Israel, Iran, Croatia, etc., on the other hand, first seemingly contained the infection, but now are hit by the second wave of outbreak. Japan was initially criticized for its policy responses at home or from abroad, the number of infections in the country stays low if viewed internationally. Thus, the spread of the novel coronavirus infection varies from country to country.

Why does the status of the novel coronavirus infection so widely differ among countries? Why has Japan been able to control the spread of infection rather well? Can Japan prevent the second wave of COVID-19?

Several hypotheses have appeared on factors that vitally affect the status of infection in each country --- differences in lifestyle such as mask-wearing and hand-washing, collective immunity against coronavirus, the possible effect of BCG vaccination, and differences in race. Whether these hypotheses are true or false must be verified by experts concerned.

This paper will delve into the correlation between policy responses and the status of the novel coronavirus infection in a number of countries. Focusing on (1) restrictions on activities (school closure, telework, the self-restraint of going out, the cancellation of events and meetings, and restrictions in movement and traffic) as well as (2) testing/contact tracing policies, we will analyze how these policy measures are related to changes in the number of new infections per day (7-day rolling average per million people). The purpose of this paper is to gain insights into policy responses necessary to prevent the spread of the novel coronavirus infection.

2. Methodology

(1) Target Countries and the Period of Survey

For the survey on which this paper is based, we selected the following 18 countries. The period of survey was from January 1, 2020 to June 30, 2020.

(2) Data

In this paper, we focused on changes in the number of newly confirmed carriers per day as an indicator to understand the current status of infection. We calculated a 7-day rolling average per million people in each target country based on the number of newly confirmed carriers per day released by WHO. The only exception is Taiwan, on which data we retrieved from the website "Our World In Data" run by the University of Oxford.

To compare policy responses taken by target countries, we used the data of "The Oxford COVID-19 Government Response Tracker" (OxCGRT) run by the University of Oxford. OxCGRT has come up with 17 indicators on government responses against COVID-19 of more than 160 countries around the world. Out of the 17 indicators, this paper employs: (1) "School closing," "Workplace closing," "Cancel public events," Restrictions on gatherings," "Close public transport," "Stay at home requirements," "Restrictions on internal movement," and "International travel controls" (8 activity limitation indicators), and (2) "Testing policy" and "Contact tracing" (2 testing/contact tracing indicators). OxCGRT evaluates the effectiveness of each indicator with a value ranging from 0 to 4. For ease of comparison, this paper evaluates the effectiveness of the above ten indicators with a value ranging from 0 to 100.

(3) Method of Analysis

Using these data, we first considered the correlation between the content of policy responses and the spread of infection. Regarding each of the ten countries in groups 1 and 3 in Table 1, we conducted a multiple regression analysis on the correlation between the above ten indicators (eight activity limitation indicators and two testing/contact tracing indicators) and the number of new infections per day (7-day rolling average per million people) at the time of 14 days after those policy responses were taken.

Next, we examined whether Japan took policy responses at a relatively early or late stage of the spread of infection compared to other countries. On February 25, 2020, the Japanese government launched full-scale policy responses with the announcement of "Basic Policies for Novel Coronavirus Disease Control." Then, Japan's activity limitation indicators rose from 17.2 to 31.0, and the number of new infections per day (7-day rolling average per million people) was 0.12. Likewise, we compared the numbers of new infections per day (7-day rolling average per million people) in the other 17 target countries when the value of activity limitation indicators exceeded 20.

Thirdly, we compared the correlation between changes in the status of infection and restrictions on activities and testing/contact tracing policies of each target country. In other words, regarding all the 18 target countries, we graphed for sequential comparison the change of restrictions on activities and testing/contact tracing policies, as well as changes in the number of new infections per day (7-day rolling average per million people).

3. Results and Discussion

(1) Contents of Policy Responses and Infection Control

We conducted a multiple regression analysis on the correlation between the number of new infections per day (7-day rolling average per million people) and restrictions on activities and testing/contact tracing policies of 10 target countries of groups 1 and 3 in Table 1. The results are shown in Table 2.

The results of this analysis indicate that it is impossible to find common characteristics among the target countries' policy responses that are in a negative correlation with the increase in new infections. Or, it is highly likely that factors peculiar to each target country, such as lifestyle and customs, are intimately related to infection control. Consequently, which of the specific policy responses --- school closures, telework, the self-restraint of going out, cancellation of events and meetings, or restrictions on movement and traffic --- is effective will vary depending on the situation of each target country.

Therefore, the above analysis results indicate that even if specific policy responses such as school closures or restraints on events help infection control in one country, the same measures will not necessarily work in other countries.

(2) The Time of Initiating Restrictions on Activities and the Spread of Infection

Next, we examined how much the speed of policy responses of each target country should affect infection control. In Japan, on February 25, 2020, when the number of new infections per day (7-day rolling average per million people) was 0.12, the government announced the "Basic Policies for Novel Coronavirus Disease Control," launching such policy responses as a request for the cancellation or postponement of large-scale events and the recommendation of telework. At this point, the value of activity limitation indicators rose from 17.2 to 31.0. We compared the numbers of new infections per day (7-day rolling average per million people) in target countries when the value of activity limitation indicators exceeded 20 and then 30. The results appear in Table 3.

Japan fully started restrictions on activities when its number of new infections per day was much smaller than the average of the 18 target countries. In Japan, more voices are criticizing the government's initial delay, but viewed internationally, the government's initial action was not fatally slow. Compared to the United Kingdom and Germany that could not resist the spread of infection, Japan's initial response was rather quick.

Meanwhile, Table 3 shows that the United States, Brazil, India, and Russia, all of which are currently facing the gravest COVID-19 outbreaks in the world, began policy responses comparable to those of Japan when they had as many daily new infections as Japan or less. That is, the speed of initial response to limit activities does not necessarily influence subsequent infection control.

(3) Restrictions on Activities and Testing/Contact Tracing Policies and the Status of Infection

Thirdly, we compared the target countries in terms of the correlation between changes in the status of infection and restrictions on activities and testing/contact tracing policies. We graphed the results as follows.

A common feature found among East Asian countries that are adequately controlling the spread of infection is that the value of testing/contact tracing indicators is high. The value of activity limitation indicators, on the other hand, does not necessarily indicate commonality. (See Figure 1)

Conversely, in both the United States and Brazil, where the spread of infection is underway, the value of activity limitation indicators is by no means low, but that of testing/contact tracing indicators is low, compared to countries that have succeeded in controlling the infection. Both India and Russia, with a high cumulative number of infections and fatalities following the United States and Brazil, are comparable to the East Asian countries successfully controlling infection, in terms of the values of both activity limitation indicators and testing/contact tracing indicators. The absolute number of infections in India is large, but that of new infections per million people in India is one digit smaller than in the United States and Brazil. In Russia, the number of new infections has peaked out. (See Figure 2)

Regarding European countries experiencing the outbreak of grave infection, the value of activity limitation indicators was high on average; the value of testing/contact tracing indicators was not high at the outset of the spread of infection. Changes in the values of activity limitation indicators and testing/contact tracing indicators show that European countries upgraded testing/contact tracing policies while enforcing restrictions on activities. (See Figure 3)

As far as countries suffering from the second wave of infection are concerned, the value of activity limitation indicators was high, but that of testing/contact tracing indicators was not so high, compared to European countries where the spread of COVID-19 has calmed down. Especially in Australia, Israel, and Iran, the easing of restrictions on activities without strengthening testing/contact tracing measures seems to have led to the outbreak of the second wave of infection. (See Figure 4)

Japan has so far managed to keep the number of infections low, even though the values of activity limitation indicators and testing/contact tracing indicators are low --- a feature that distinguishes the nation from other East Asian countries that are controlling the infection relatively well. This may be credited to factors such as differences in lifestyle --- mask-wearing and hand-washing, existing collective immunity against coronavirus, the effect of BCG vaccination, and differences in race. Another reason may be that Japanese people have complied with the government's non-compulsory request for restrictions on activities. However, like countries that have been hit by the second wave of outbreak, Japan has eased restrictions on activities without sufficiently strengthening testing/contact tracing measures. As a result, the number of recent new infections per day (7-day rolling average per million people) is on the rise.

5. Conclusion

This paper examined the correlation between policy responses and the status of the novel coronavirus infection in each target country. The results of analysis and discussion are summarized as follows.

(1) Which of the specific policy responses --- school closures, telework, the self-restraint of going out, the cancellation of events and meetings, or restrictions on movement and traffic --- is effective will vary depending on the situation of each target country.

(2) The speed of initial response to limit activities does not necessarily influence subsequent infection control.

(3) Regarding countries that are controlling the spread of infection relatively well, the intensity of restrictions on activities varies between countries, but thorough testing and contact tracing is a shared feature.

(4) Severe restrictions on activities prevent the spread of infection in many countries, but the second wave of outbreak occurs in such countries that have eased restrictions on activities without the capability of implementing thorough inspection and contact tracing.

In short, this paper concludes that testing and contact tracing is more vital than restrictions on activities to control the spread of infection. This point is especially important when we consider balancing infection control and economic activities. Severe limitations on activities will lead to a stagnant economy in terms of production and consumption and have a profound impact on people's life. However, the experiences of China, Taiwan, and South Korea show that thorough testing and contact tracing is capable of achieving infection control, if we do not necessarily enforce severe restrictions on activities. Conversely, without thorough testing and contact tracing, even if the spread of infection could be temporarily suppressed by restrictions on activities, the infection would immediately break out again, as soon as the restrictions have been eased --- as is evident from the experiences of Australia, Iran, and Israel. Different from these countries, Japan seems to have overcome the first wave of infection since Japanese people complied with the government's non-compulsory request for restrictions on activities. However, Japan is highly likely to face the second wave of COVID-19 because she eased the self-restraint request without fully strengthening the system of testing and contact tracing.

References

proposal
current topics
letter