Incidence and effects of Varicella Zoster Virus infection on academic activities of medical undergraduates - a five-year follow-up study from Sri Lanka

Abstract

BackgroundThe adult population in Sri Lanka is having high level of susceptibility for Varicella Zoster Virus (VZV) infection. Among medical undergraduates, 47% are VZV seronegative. The purpose of the present study was to determine the incidence of VZV infection in medical undergraduates in Sri Lanka, and to describe the effects of VZV infection on their academic activities.MethodsA retrospective cohort of medical undergraduates' susceptible for VZV infection was selected from the University of Peradeniya, Sri Lanka. Data on the incidence of VZV infection (Chickenpox) during their undergraduate period was collected using a self-administered structured questionnaire. A second questionnaire was administered to collect data on the details of VZV infection and the impact of it on their academic activities. VZV incidence rate was calculated as the number of infections per 1,000 person years of exposure. Descriptive statistics were used to describe the impact of VZV infection on academic activities.ResultsOut of the 172 susceptible cohort, 153 medical undergraduates were followed up. 47 students reported VZV infection during the follow up period and 43 of them participated in the study. The cumulative incidence of VZV infection during the period of five and half years of medical training was 30.7%. Incidence density of VZV infection among medical undergraduates in this cohort was 65.1 per 1,000 person years of follow-up. A total of 377 working days were lost by 43 students due to the VZV infection, averaging 8.8 days per undergraduate. Total academic losses for the study cohort were; 205 lectures, 17 practicals, 13 dissection sessions, 11 tutorials, 124 days of clinical training and 107 days of professorial clinical appointments. According to their perception they lost 1,927 study hours due to the illness (Median 50 hours per undergraduate).ConclusionsThe incidence of VZV infection among Sri Lankan medical undergraduates is very high and the impact of this infection on academic activities causes severe disruption of their undergraduate life. VZV immunization for susceptible new entrant medical undergraduates is recommended.

Prevalence of measles, mumps, rubella, and varicella susceptibility among health science students in a University in India

“…However, data from other countries such as Japan [Yoshida, et al 2007], Slovenia [Socan and Berginc 2008] and Greece [Pavlopoulou, et al 2009] indicate a lower susceptibility of HSS to these diseases (range, 0.7% to 14.3%). Our finding of about 50% of HSS susceptible to varicella is comparable to reports from Sri Lanka [Agampodi, et al 2010, Kurukulasooriya, et al 2010], but not with other countries such as Australia [Torda 2008], Greece [Pavlopoulou, et al 2009], Japan [Yoshida, et al 2007], Slovenia [Socan and Berginc 2008] and Thailand [Bhattarakosol, et al 1996], which report a much lower susceptibility (range, 2.4 % to 25.7%). The susceptibility of HSS to these diseases is dependent on the immunization policy practiced in each country.…”

Epidemic Varicella Zoster Virus among University Students, India

“…Although studies in India and Thailand show that community transmission and household crowding predispose to varicella epidemics ( 8 ), transmission in a tertiary education setting has not been described. A serologic study of undergraduate students in Sri Lanka further suggests high susceptibility in this cohort ( 9 ). …”

Epidemiology and factors influencing varicella infections in tropical countries including Sri Lanka

“…Although high susceptibility rates for VZV infection have been reported, the actual morbidity and mortality data for the infection remains incomplete in Sri Lanka. In 2003, 1749 patients with VZV infections were admitted to the Government Hospitals in Sri Lanka [2] and in 2009, an outbreak with 12,000 cases were reported among internally displaced individuals in Vavuniya (http://www.internaldisplacement.org/assets/library/Asia/Sri-Lanka/pdf/Sri-Lanka-November-2009.pdf). Hence, the total number of VZV infections in 2009 reached a peak of 14,407 with the outbreak reported in Vavuniya.…”