Burden of influenza A (H1N1)pdm09 infection among tuberculosis patients: a prospective cohort study

Gulshan Umbreen; Abdul Rehman; Muhammad Avais; Chanda Jabeen; Shakera Sadiq; Rubab Maqsood; Hamad Bin Rashid; Saira Afzal; Mamoona Chaudhry

doi:10.1186/s12879-023-08441-3

Burden of influenza A (H1N1)pdm09 infection among tuberculosis patients: a prospective cohort study

BMC Infect Dis. 2023 Aug 10;23(1):526. doi: 10.1186/s12879-023-08441-3.

Authors

Gulshan Umbreen¹, Abdul Rehman¹, Muhammad Avais², Chanda Jabeen¹, Shakera Sadiq¹, Rubab Maqsood¹, Hamad Bin Rashid³, Saira Afzal⁴, Mamoona Chaudhry⁵

Affiliations

¹ Department of Epidemiology & Public Health, University of veterinary and Animal Sciences, Lahore, Pakistan.
² Department of Veterinary Medicine, University of veterinary and Animal Sciences, Lahore, Pakistan.
³ Department of Veterinary Surgery, University of Veterinary and Animal Sciences, Lahore, Pakistan.
⁴ Department of Community Medicine, King Edward Medical University, Lahore, Pakistan.
⁵ Department of Epidemiology & Public Health, University of veterinary and Animal Sciences, Lahore, Pakistan. mamoona.chaudhry@uvas.edu.pk.

Abstract

Background: Influenza and tuberculosis both cause significant morbidity and mortality worldwide. Therefore, this study aimed to estimate the burden of influenza A (H1N1)pdm09 virus infection among human tuberculosis patients and the general population.

Methods: A prospective cohort study was conducted among a cohort group (TB positive patients) as exposed and a comparison group (general population) as non-exposed. A total of 304 participants were recruited in both groups and followed for a period of 12 weeks. Of the 304 concurrently enrolled individuals, 152 were TB-positive patients (cohort group) and 152 were from the general population (comparison group).To calculate the sample size, the power of study was kept at 80% for detecting a difference at 5% alpha level assuming the 25% prevalence of respiratory viruses in cohort group compared to 12.5% in general population. An oropharyngeal swab was taken from a participant with symptoms of influenza-like illness (ILI). Samples were tested by conventional reverse transcription polymerase chain reaction (RT-PCR) for the detection of influenza A (H1N1)pdm09. All statistical analyses were conducted using R software.

Results: A total of 95 participants developed influenza-like illness (ILI) symptoms. Among these, 64 tested positive for influenza A(H1N1)pdm09, of which 39 were from the exposed group and 25 were from the non-exposed group. During the 12-week period of follow-up, the influenza A (H1N1)pdm09 incidence rate was 20 per 1000 people. The risk of testing positive for influenza A (H1N1)pdm09 was 1.66 times higher in the exposed group compared to the non-exposed group. The cumulative incidence indicated that 25% of the TB cohort and 16% of the comparison group were at risk of getting influenza A (H1N1)pdm09 during the 12 weeks of follow-up.

Conclusion: Participants from the TB cohort had a higher incidence of influenza A (H1N1)pdm09 than the general population suggesting that they should be prioritized for influenza vaccination.

Keywords: Cohort studies; Humans; Incidence; Influenza; Prospective studies; Tuberculosis; Viruses.

MeSH terms

Humans
Influenza A Virus, H1N1 Subtype*
Influenza, Human* / complications
Influenza, Human* / epidemiology
Prospective Studies
Tuberculosis* / epidemiology
Virus Diseases*