Overview
Secondary infections refer to infections that occur during or after the treatment of a primary infection, often due to a weakened immune system or disruption of normal flora. Characterizing the severity of secondary cases can help understand the true burden of an emerging infectious disease and identify missed cases 2.
Diagnosis
Information on disease severity in secondary cases may be less susceptible to ascertainment bias compared to index cases 2.
Secondary cases may have a lower proportion of fever, symptomatic illness, hospitalization, and fatal outcomes compared to index cases 2.Management
No specific management strategies for secondary infections are discussed in the provided abstracts.Special Populations
HIV-infected COVID-19 patients did not show a statistically significant increased risk of mortality compared to COVID-19 patients without HIV infection 1.
The mortality rate due to COVID-19 was 7.97% among HIV-infected patients and 0.69% among non-HIV-infected patients 1.Key Recommendations
Consider using disease severity information from secondary cases to estimate the true severity of an emerging infection and the proportion of missed index cases 2. (Evidence: Moderate)
HIV infection was not associated with an increased risk of COVID-19 mortality in a meta-analysis of 16 studies 1. (Evidence: Moderate)References
1 Dzinamarira T, Murewanhema G, Chitungo I, Ngara B, Nkambule SJ, Madziva R et al.. Risk of mortality in HIV-infected COVID-19 patients: A systematic review and meta-analysis. Journal of infection and public health 2022. link
2 Tsang TK, Wang C, Yang B, Cauchemez S, Cowling BJ. Using secondary cases to characterize the severity of an emerging or re-emerging infection. Nature communications 2021. link