Under-reported COVID-19 cases in South Asian countries [ version 2 ; peer review : 3 approved ]

Background: The purpose of the study was to compare  trends in the progression of COVID-19 among South Asian countries with more developed Western countries. Methods: COVID-19 data from South Asian countries were used for this observational study. Data were taken up to April 21, 2020 from the outbreak of the COVID-19. Four of the seven countries met the inclusion criteria and were included in the analysis. Results: An exponential increase in the average number of weekly cases was reported after the fifth week following the first case. The correlation between reported cases and tests was found to be strong and significant (r=0.90, p=0.037). However, on average, 315.25 tests per million population were performed, which was at least 12 times lower than the number of tests performed in countries with a large number of COVID-19 cases. Conclusions: At present, the number of confirmed cases from South Asia was found to be significantly lower than in Western countries. Hence, an increase in the strength of performing diagnostic tests is highly recommended. Strict measures are required to make the people of these countries follow the instructions of social distancing and comply with preventive measures.


Introduction
Any outbreak of an infectious disease or a natural disaster on a large scale, which spreads over a large geographical area leading to morbidity and mortality, is known as a pandemic. Evidence suggests that the likelihood of pandemics has increased over the past century because of an increase in global travel, urbanization, and greater exploitation of the natural environment 1 . Consequences of pandemics are multidimensional, have an impact on global health, socioeconomic conditions, and political implications 2 . The recent outbreak of coronavirus disease (COVID-19) was reported in the Huanan Seafood Market in Wuhan, China. China is therefore considered as the epicenter of the disease 3 . However, in the current scenario, some European countries and the United States of America (USA) have become new epicenters of the disease. Individually, these countries have more than twice the number of reported cases when compared to China. Meanwhile, their death toll is at least five times greater than in China 4 . During the second week of March, the COVID-19 outbreak was declared a pandemic by the World Health Organization (WHO) 5 .
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that causes COVID-19, belongs to the same family of corona viruses that includes the Middle East respiratory syndrome virus (MERS-CoV) 6 . Signs and symptoms of COVID-19 include respiratory symptoms, fever, cough, and shortness of breath. These breathing difficulties can worsen over time, and the disease can lead to complications such as: pneumonia, severe acute respiratory syndrome, kidney failure, and even death. People with low immunity and underlying systemic diseases are more prone to SARS-CoV-2 infection 7 . This is why the highest death rates are reported in the elderly population among those who were infected by COVID-19 8 .
Various precautionary methods have been adapted by countries to control and stop the spread of COVID-19. A few such measures include hygiene maintenance, public awareness, partial lockdown, complete lockdown, and even the imposition of curfews 9 . Currently, social distancing is the only recognized way to prevent the spread of the virus. Hence, countries are making decisions based on their circumstances and the experiences of other countries 10 . Based on data extracted from the WHO database, the progression of the disease and deaths in various regions and countries differ 11 . Statistics show a high number of reported COVID-19 cases and deaths in some European countries and in the USA as well. The first confirmed case of COVID-19 in some South Asian countries like India and Sri Lanka was reported on 15 th of February 2020 while in Pakistan and Bangladesh, the first confirmed case was reported on 26 th February and 8 th March respectively. The trend in average weekly increases in reported cases remained untested. Therefore, the objective of the current study was to find the trend in the progression of COVID-19 among South Asian countries compared to more developed Western countries.

Methods
This observational study was conducted between 20 th April and 22 nd April 2020. The study included COVID-19 data available from worldometer® 12 . Data was extracted from the date of the first COVID-19 case reported up until 21 st April 2020. Data was extracted for all South Asian countries that were affected by the current outbreak. Only countries with at least 100 reported cases by 21 st April 2020 were included in the study and reason to do so was to prevent the analysis process from outliers' effects as well as to keep pictorial presentation visualized. Hence, a total of four out of the seven countries were included in the study: India, Pakistan, Sri Lanka, and Bangladesh.
The variables taken from the data source were: (1) total reported cases, (2) total deaths, (3) total recovered, (4) number of cases with outcome, (5) number of serious/critical cases, (6) total cases per one million population, (7) total tests performed, and (8) total tests performed per one million population. Furthermore, a few more variables were calculated using the extracted data and variables. The total outcome was calculated by adding the total number of deaths and the total number of recoveries. Percentage of deaths was calculated by using the equation [total deaths / (total deaths reported + total recovered) x 100%], the percentage of recovered cases was calculated as [total recovered/ (total deaths reported + total recovered) x 100%], the percentage of critical cases as "number of critical cases/active cases × 100%", and the ratio of the number of cases tested by dividing the total number of cases by the total number of tests performed. The weekly number of cases reported after the first case reported until 21 st April 2020 was also extracted from the data source. For the descriptive comparison of the present study's findings of countries with a high number of COVID-19 cases, some of the statistics are summarized in Table 1 10 .
The statistical package for social sciences (SPSS v. 23) was used for the analysis. Descriptive statistics included the calculation of averages and standard deviations as well as line graphs to present the number of weekly reported cases in each country. In inferential statistics, a simple linear regression was used between total cases (dependent variable) and total tests performed (independent variable). The Wilcoxon signed-ranks test was used to analyze the weekly increase in COVID-19 cases.

Results
The total number of reported COVID-19 cases in South Asian countries by 21 st April 2020 were 31,565 of which 5,526 (17.5%) recovered. The number of reported deaths was 901. Among South Asian countries, India had the highest number of positive  Table 2). The percentage of reported deaths was highest in Bangladesh (55.84%), followed by India (15.32%), Sri Lanka (6.54%), and Pakistan (8.5%). Figure 1 shows the exponential growth in the number of reported cases among the South Asian countries after the fourth to fifth week since the start of the disease. A sharp increase was observed in reported cases in India from the sixth week onwards. In Pakistan, the number of reported cases was also found to increase at the start of the fourth week. However, the spread of the virus was not as rapid in Bangladesh and Sri Lanka, as was found in the Indian and Pakistani populations. A comparison of the average number of reported cases in each week with the previous week revealed that the average increase in cases was not statistically significant except between fifth and sixth week (z-value -2.02, p-value 0.043). Figure 2 presented descriptive comparison of the average number of confirmed cases between two consecutive weeks.
On average, 315.25 tests per million population were performed in the countries included in the current study. A correlation between the total reported cases and the total number of tests performed was found. The data revealed a very strong, direct, and statistically significant correlation (r=0.90, p=0.037). The Bangladeshi population had the highest percentage of tested positive cases in relation to the total number of tests performed (12.71%), followed by Pakistan (8.24%), Sri Lanka (4.78%), and India (4.65%). Based on the preparedness index formulated by Greenhill and Oppenheim, which defines the ability of a country to curtail any pandemic 13 , the spread risk of this pandemic is higher in South Asian developing countries than in developed countries 14 .
A few of the factors that contribute to a higher spread risk of the pandemic include population density, susceptibility to infection, patterns of movement driven by travel, trade, and migration, the speed and effectiveness of public health surveillance and response measures, and the socioeconomic status of the country 14 . Three out of four countries included in the current study fall under the top ten most populated countries in the world 15-17 . Furthermore, the per km 2 population in Bangladesh, India, and Pakistan is more than any country listed in Table 1.
In addition, a large number of people in these countries live in slums 15-17 , which makes it difficult to maintain social distancing and to adopt preventive measures. Furthermore, poor education and extreme poverty are other factors that make it more difficult to follow social distancing instructions, or early disease identification of symptoms of COVID-19. A report from Pakistan showed an increasing number of cases where people died due to COVID-19 before reaching a hospital 18 .
To date, there has been a total of 2,505,858 reported cases of COVID-19 worldwide, with a lower number of reported cases (31,608) and reported deaths (901) in South Asian countries compared to other regions of the world. There have been many hypotheses related to this lower reported COVID-19 cases and deaths. Some of the theories included stronger immunity, warmer weather, childhood BCG vaccinations, and exposure to antimalaria medications. From the data collected from the worl-dometer® website, the authors believe that the lower number of reported cases in the South Asian countries could be due to the lower number of diagnostic tests performed for COVID-19 virus compared to countries that have reported a higher number of COVID-19 cases. India (18,658) and Pakistan (9,216) have the most COVID-19 cases in South Asian countries, with 291 and 506 tests performed per million population, respectively. The number of tests (per million) performed in India and Pakistan is significantly lower than in the USA (12,167), Spain (19,896), Italy (23,122), France (7,103), and the UK (7,386). Even countries in Asia with the highest number of COVID-19 cases, Turkey (7,991) and Iran (4,203), have a higher number of tests performed per million population. In South Asia, on average, 315.25 tests per million population were performed; this is at least 12 times lower than the number of tests performed in the epicenters of COVID-19.
Even though the world is better prepared to face any health crisis than before, still the world is not fully prepared to handle a pandemic. Preparedness for any crisis does affect from financial status of any country hence financially strong countries would have better chances to have more health care facilities, resources, infrastructures to cope with any crisis. In present time, world is facing a pandemic and so far, its deep impact can be seen in various continents however it is not significantly hit south Asian countries yet.
Accountability for preparedness in these countries is diffuse, and many countries that are at the greatest risk have the most limited capacity to manage and mitigate pandemic risk. In addition, these countries need to perform the virus diagnostic tests in greater numbers to get an accurate picture of the pandemic. Based on the data, one could suggest that the low number of reported cases but with high percentage increases for South Asian countries could be a ticking time bomb waiting to explode, and this region could be the next highlighted region of this current pandemic.

Conclusions
Although the current number of reported cases and reported deaths from South Asia suggested that the spread of COVID-19 is not as high as it was in many other countries. However, a comparison of statistics and population characteristics does not portray a good picture for the future. Therefore, the following conclusions can be drawn: 1. One side of the picture is a lower number of reported cases and deaths, but the other side of the picture suggests a large number of cases that are prevailing in the society that are unidentified and undiagnosed. Hence, identifying the spread of the disease by increasing the number of diagnostic tests is highly recommended.

2.
Governments in these countries are required to take strict measures such as partial or complete lockdowns in order to maintain proper social distancing, since a high population density coupled with low education levels and low disease awareness could lead to a new disease epicenter.

Open Peer Review
Thank you for the opportunity to review this article. This article is related to the most pressing health crises faced by mankind i.e COVID-19. The article is well written and adheres to the formatting of the journal.
Few points need clarification, In the methodology, the authors state that only data from South Asian countries have been included. However, the data from other developed countries have also been included for comparison. 1.

Discussion:
a) Kindly avoid restating the results in the discussion section.
b) The authors should discuss the variations in the COVID-19 testing policies that the countries adopted initially , as it is variable from country to country and can alter the number of tests. Also, in the discussion the authors should elaborate on the timings and implementation of the country wide lockdown in the countries, that could have affected the rate of spread of COVID-19.

2.
Is the work clearly and accurately presented and does it cite the current literature? Yes

Is the study design appropriate and is the work technically sound?
However, the article highlights the importance of social distancing and preventive measures that needs to be implemented in these countries which are the most economic preventive measures.

Is the work clearly and accurately presented and does it cite the current literature? Yes
Is the study design appropriate and is the work technically sound? Partly

If applicable, is the statistical analysis and its interpretation appropriate? Partly
Are all the source data underlying the results available to ensure full reproducibility? Yes Are the conclusions drawn adequately supported by the results? Yes