JMIR Publications

ABSTRACT

Background:

The SAR-CoV-2 virus, that causes COVID-19, has led to an unprecedented global pandemic resulting in significant morbidity and mortality. Countries have had varying success at implementing COVID-19 control policies to mitigate infections and to prevent future transmissions of the novel coronavirus. COVID-19 transmissions in South Asia are concerning because it is home to approximately 25% of the world’s population. Public health surveillance is needed to inform South Asian leaders understand when and where transmission rates are increasing.

Objective:

To improve surveillance by using standard surveillance metrics with novel complementary decomposable surveillance metrics that overcome data limitations and contamination inherent in public health surveillance systems. In addition to prevalence of observed daily and cumulative testing, testing positivity rates, morbidity and mortality, we surveil COVID transmission in terms of: 1) speed, 2) acceleration or deceleration, 3) change in acceleration or deceleration (jerk), and 4) 7-day persistence (the number of new today that are statistically attributable to new cases seven days ago). These additional surveillance indicators improve our understanding of where and how rapidly SARS-CoV-2 is transmitting, and quantifies shifts in the rate of acceleration or deceleration to inform policy targeting mitigation and prevention strategies in South Asia.

Methods:

We extracted 60 days of COVID data from public health registries and employed longitudinal trend analysis. In addition, we use an empirical difference equation to measure daily case numbers in eight South Asian countries as a function of the prior number of cases, the level of testing, and weekly shift variables based on a dynamic panel model that was estimated using the generalized method of moments (GMM) approach by implementing the Arellano-Bond estimator in R.

Results:

COVID transmission rates were tracked for South Asia during the weeks of 9/15-9/22 and 9/22-9/29. Observed regional new cases totaled 568,427 with an average of 10,150 observed new cases per day per country for the week of September 22 while observed new cases totaled 604,704 with an average of 10,798 observed new cases per day per country for the week of September 29. Infection rates varied by country.Both acceleration and jerk were negative or close to 0 during the week of 9/22 in all South Asian countries. Maldives, India, and Nepal had the most promising numbers at -1.0, -0.9, and -0.1 respectively. For the week of 9/29, acceleration increased to 0.8 and jerk increased to 0.9, indicating the rate of infections and the acceleration of infections were on the rise. Maldives and Nepal acceleration increased to -0.3 and 0.1 respectively while their jerk moved to -0.6 and 0 respectively. Surveillance data must be contextualized by country population. Among the top most populous countries in South Asia are India, with the largest population, followed by Bangladesh, Afghanistan, Nepal, and Sri Lanka. India is more than six times larger than the next largest country in the region, Pakistan, and almost three times larger than the total population of all other countries in the region combined.

Conclusions:

1) Standard surveillance metrics such as daily observed new COVID-19 cases or deaths are necessary but insufficient to mitigate and prevent COVID transmission. Public Health leaders also need to know where and how COVID-19 transmission rates are accelerating , whether those rates increase or decrease over short time frames because the pandemic can quickly escalate, and how many cases today are a function of new infections 7 days ago; and 2) Even though South Asia is home to some poor countries, development and population size are not necessarily predictive of COVID-19 transmission. Moreover, even though the United States leads the world in COVID-19 infections and deaths, India’s caseload will soon outnumber the U.S. because rapid speed, rising acceleration, and positive jerk. Unless the transmission rates reverse course, current trends combined with the large population of India assure it will become the global leader in COVID-19 caseloads in the very near future. Clinical Trial: NA