RSV
Definition
Respiratory syncytial virus (RSV) is a respiratory illness that affect children and the elderly. Can’t go to much into detail, but it’s part of my work.
Seasonality
So it’s an extremely seasonal disease with the northern hemisphere starting in fall while the southern hemisphere starts sometime in spring. Lot of our forecasting techniques (ARIMA, Holt-Winters, Prophet,and even compartmental modeling (SIR Model (General)) with a pretty fixed seasonal transmission curve) did really well.
However, post-COVID-19, and the seasonality has changed considerably. I did a compartmental model for post-COVID and it fit bad. Also it could be possible that the introduction of antibodies for RSV around 2024 have also affected it.
Is the seasonality reverting back to COVID-19 days is kind of an interesting open question at work.
Important biology to consider
- Immunity wanes, but we get reinfected even in our adulthood
Mathematical modeling
- Standard SIRS model works well with a seasonal transmission term.
- Age-structured SIRS model
- A complex age-structure that may be the most informative is:
- <2m,
- 2-3m,
- 4-5m,
- 6-7m,
- 8-9m,
- 10-11m,
- 12-24m,
- 2-4 yrs,
- 5-9 yrs,
- 10-19 yrs,
- 20-39 yrs,
- 40-59 yrs,
- 60-74 yrs,
- ≥75 yrs
- A complex age-structure that may be the most informative is: