Prevalence of SARS-CoV-2: An age-stratified, population-based, sero-epidemiological survey in Islamabad, Pakistan

Abstract

Introduction: Serological surveys are valuable tools to evaluate the extent of disease transmission, measuring preventive effectiveness and proportion of asymptomatic individuals. This age-stratified, serological survey was aimed to measure the COVID-19 distribution and determinants in district Islamabad of Pakistan. Methodology: Three-stage cluster sampling, using population proportionate to size technique, starting with a random number was used. A structured, pretested questionnaire was used after taking informed written consent, to gather demographic, risk factor information. Results: Seroprevalence was found 16.5% (AR: 16.5%/100,000). The mean age was 35 (sd:16 Years). The majority were male (64%), self-employed (29%), and had primary level education (33%). The highest seroprevalence was found in the 21-30 years age group (24.8%) while the 41-50 years age group showed the highest attack rate (112.9/100,000 population). The proportion of the population tested that were asymptomatic was 69% (n=711) while the most frequently reported sign/symptom was cough (99%) followed by fever (20%). No known co-morbidity was reported in 86% (n=884) of respondents while hypertension remained the most reported condition (8%). High seroprevalence was observed in urban areas (12.3%) compared to rural union councils (6.4%). Visiting a house where COVID-19 case was isolated (OR 2, CI 1.38-2.84, P< 0.001), history of contact with a known case of COVID-19 (OR 1.42, CI 1.11-1.82, P=0.005), and attending a mass gathering (OR 1.21, CI: 1.02-1.42, p=0.02) were significant risk factors associated with contracting an infection. A Chi-Square test of independence showed significant protection while using regular hand hygiene practices (6.5; p<0.05) and regular usage of face masks (8.6; p<0.05). Conclusion: Seroprevalence gives a direct estimation of population groups exposed to the virus. A remarkable difference in prevalence is found in urban and rural areas, extreme age groups, and socioeconomic statuses, suggesting targeted public health interventions. Sero-studies are affordable counterparts of molecular testing where quick estimation, prevention effectiveness, and data-driven public health policies are priorities.

Effectiveness of face masks for reducing transmission of SARS-CoV-2: a rapid systematic review

“…Table 2 summarizes the number of studies addressing each type of comparison studied and the direction of their conclusions. There were 35 studies set in the community (three RCTs (14-16), 32 observational studies [15][16][17][18][19]48] and 40 studies situated in healthcare settings including hospitals and long-term care facilities (LTCFs) (one RCT [72], 39 observational studies [73][74][75][76][77][78][79][80][81][82][83][84][85][86][87][88]).…”

“…[ 17 ] observational India masks for reducing transmission testing (method not specified) contact tracing Baig et al . [ 18 ] observational Pakistan masks for reducing transmission serology (CLIA or ELISA) questionnaire Boutzoukas et al . [ 19 ] observational USA mask mandates for reducing transmission testing (method not specified) mandate data Bundgaard et al .…”

“…Forty-seven studies reported on the effectiveness of masks for reducing transmission of SARS-CoV-2 as their primary outcome: 24 studies (two RCTs, 22 observational) in community settings [ 14 – 18 , 20 , 21 , 23 , 25 – 27 , 29 , 33 , 34 , 36 – 41 , 43 , 44 , 46 , 48 ] and 23 observational studies in healthcare settings [ 50 , 53 – 61 , 63 – 66 , 68 , 69 , 75 – 77 , 81 , 82 , 84 , 85 ].…”

“…Five studies concluded that masks had no significant effect on transmission, and one favoured the control group. Notably, the study favouring controls [ 18 ] is one of the three preprints included in this review; it had not been peer reviewed nor subsequently published, and the data presented are inconsistent with the authors' own conclusion that masks were protective.…”

“…Forty-seven studies reported on the effectiveness of masks for reducing transmission of SARS-CoV-2 as their primary outcome: 24 studies (two RCTs, 22 observational) in community settings [14][15][16][17][18]20,21,23,[25][26][27]29,33,34,[36][37][38][39][40][41]43,44,46,48] and 23 observational studies in healthcare settings [50,[53][54][55][56][57][58][59][60][61][63][64][65][66]68,69,[75][76][77]81,82,84,85].…”