Journal of Preventive Medicine

Introduction

COVID-19 is pandemic respiratory infectious disease with unknown etiology, was first reported to the WHO office on Dec 31st 2019, from Wuhan, a metropolitan city in the province of Hubei China [1]. Case fatality rate of 2.3% has been reported from china that is lower than SARS (9.5%), MERS (34.4%) and H7N9 (39%) [2].

In Pakistan the virus entered on 26th February, 2020, when Government of Pakistan officially declared a student of university of Karachi diagnosed as COVID-19 positive, with a travel history of Iran [3]. In Pakistan the literature so for covering the prevalence and incidence is deficient and we found no published data, In Pakistan the so for reported data from government sources declares 30941 confirmed cases with 667 deaths. Punjab is the province with highest number of corona cases crossing 11568 cases followed by Sindh (11480), KP (4669) and Balochistan with 2017 confirmed cases [4]. In order to help the clinicians and to understand the burden of the disease, we analyzed the cases of District Nowshera where so for 385 cases PCR results.

Present pilot study was designed with the objectives as:

1. To determine the frequency of positivity of the cases in the asymptomatic patients attending the COVID-19 clinic of a tertiary care hospital and

2. Frequency of positivity of the cases in cases with strong history of contact/travel to an epidemic or patients in district Nowhsera.

Material and Methods

This cross sectional study was conducted from 10^th Feb 2020 to May 8^th, 2020 in district Nowshera and its only Medical Teaching Institution, Qazi Hussain Ahmed Medical Complex MTI Nowshera. A total of 243 patients whose PCR report was received were included in this pilot study.

Ethical approval was obtained from the institutional ethical review board of Nowshera Medical College hospital administration before the execution of the study.

Prior informed consent was obtained from all suspects and they were assured of confidentiality.

All samples were sent under strict observance of protocols to the Public health research laboratory of Khyber medical university Peshawar (a designated Lab for PCR of 2019nCoV by the Government of Khyber Pukhtunkhwa).

Data was entered in SPSS 25^th version and descriptive and correlation statistics were applied. The frequency and proportion of numerical and categorical and were presented in percentages. Descriptive statistics was used for age to determine the mean with standard deviation. Chi-square test was applied to show a relationship of viral infectivity in age.

Results and Discussion

The mean with SD of age was 36 years+16 years; the minimum age of the suspects was 2 years with a maximum 0f 85 years and range of 83 years.

We enrolled a total of 629 patients in district Nowshera in COVID-19 data system. Out of total, 337(53.6%) were enrolled from the COVID-9 clinic of Qazi Hussain Ahmed Medical Complex and 292(46.4%) were selected from the from the district surveillance system.

Out of the total suspects 114/629 (18.1%) were COVID-19 Positive (Table 1a).

Table 1a: Frequency of positive cases: Positive cases in suspects, attending the COVID-19 Clinic (n=629).

Tian S et al reported from the Beijing China a lower prevalence rate of COVID-19 among the asymptomatic individuals in the early days of epidemic was 5% [5,6]. While another study from Japan reported a higher proportion in asymptomatic of 17.9% (95% confidence interval (CI: 15.5-20.2%). They further stated that infection in majority of patient have occurred before they join quarantine6. Luo L et al reported that the frequency of COVID-19 in his study at 10% that coincides our findings [7]. In many countries they keep in mind certain risk factors in the form of age, gender, travel history, higher markers level like d-dimers and serum ferritin etc. are the clues that helps clinicians to identify patients for further trial, before advising the patient PCR under limited resources.

We further observed that out of 385 cases, PCR was advised, among those strong suspects who were shortlisted for testing on the basis of a scoring system due to limited viral transport media (VTM), The ratio of positivity was 114/385 (29.6%) (Table 1b). Anzari A et al also reported 30% infectivity rate in their tested population [8]. They studied patients with history of travel to epidemic areas and patients with history of positive contacts.

Table 1b: Frequency of positive cases in the strong suspects whose PCR was done (n=385).

We applied Chi-square test and a statistically significant difference was noted among the age groups (p=0.006) for positive cases (Table 2).

Table 2: Relation of viral infectivity with age.

A CDC report from China showed 80% of the causalities (deaths) due to COVID-19 were in the adults aged>60 years as compared to 0.1% in person aged <19 years [9]. Similarly Italy is the second mostly affected country in the world, with more thah40000 cases of SARS-CoV infection. They reported a higher mortality in aged people as compared to younger population that identifies an immunity gap [10] (Table 3).

Table 3: pcrct * age2 Crosstabulation.

That is the point where the message to “stay at home” comes true, as whenever an individual has more history of travel he exposes himself to a higher infectivity with 2019-nCoV, by coming across with contacts of COVID-19 patients. Therefore the best only option to contain the virus is to reduce mobility, to reduce contacts and to appraise the message of social distancing.

There were some un-avoidable limitations in the study like limited resources, limited VTM/UTM, short duration of study and low number of positive cases, though we had an acceptable population of suspects.

Conclusion

We concluded that infection with 2019-nCoV is more in aged population as compared to younger population that identifies its opportunistic nature and love for immunity gap. Similarly it has a strong correlation with travel history to an infected area and positive contact history.

There is need for integrated approach through advocacy and social mobilization for social distancing. Therefore it is further suggested that special care should be given to suspects with higher risks like in age <5years & age >60 years, patient with close contact, suspects with history of travel to an epidemic area and patients with weak immune status.

References

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3. Pakistan prepares to fight back as two coronavirus cases emerge in country (2020) Arab News PK.
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